Seminar 12 - Traumatic Head Injury

Question 1

List the clinical features of wound infection

Answer 1

Signs and symptoms of infection – pain, localized swelling, redness or heat
Purulent discharge
Unexplained persistent pyrexia
Malodor from the wound
Spreading – crepitus, malaise, loss of appetite

Question 2

How does the body normally deal with cells which have had their DNA damaged by UV

Answer 2

DNA damage is sensed by checkpoint kinases e.g. ATM and ATR
These send out signals that upregulate the expression and stability of p53
This arrests cells in the G1 phase of cell cycle and promotes either high-fidelity DNA repair or the elimination of cells that are damaged beyond repair

Question 3

In DIC where are the procoagulants released from

Answer 3

They can be released from a variety of locations such as the placenta in obstetric complications and damaged tissues in severe trauma and burns.

Question 4

Which microbiology style tests may be performed on wound infection

Answer 4

Organisms isolated from the aseptically obtained wound culture
Gram stain for infective organisms; staining for fungal elements
Test for antigens from the organism through ELISA
Detection of antibody response to organism in host sera
PCR to detect small amounts of microbial DNA

Question 5

List the ABCDE warning signs of melanoma

Answer 5

Asymmetry
Border – Ragged, notched, uneven, blurred
Color – Shades of black, brown and tan (variegated)
Diameter – Usually larger than 6mm (increasing diameter)
Evolving – Has been changing; texture of mole may become hard or lumpy

Question 6

List potential causes of high grade sarcoma

Answer 6

Genetic conditions

Radiation – emergence of radiation-induced genetic mutations that encourage neoplastic transformation

Chronic lymphedema

Environmental carcinogens – Infection-induced soft-tissue tumour is Kaposi sarcoma resulting from human herpesvirus type 8 in patients with HIV

Infection

Trauma

Question 7

What is a subarachnoid haemorrhage

Answer 7

Extravasation of blood into the subarachnoid space (SAS).

Question 8

List the microscopic features of subacute (evolving) focal ischaemic infarcts

Answer 8

At 48-72hrs phagocytic cells are evident. In the following 2-3weeks they will become the predominant cell

The macrophages can persist in these lesions for months to years and they become stuffed with blood or products of myelin breakdown

As early as one week after the insult reactive astrocytes and newly formed vessels can be seen at the infarcts periphery

Astrocytes at the edge of the lesion will progressively enlarge, divide and develop a network of cytoplasmic extensions as liquefaction and phagocytosis continues

Question 9

List the immediate compensatory mechanisms for rising ICP

Answer 9

Decrease in CSF volume by moving it out of foramen magnum

Decrease in blood volume by squeezing sinuses

Question 10

Non-infectious vasculitis can also cause focal ischaemic CVA - true or false

Answer 10

True

Polyarteritis Nodosa and other non infectious vasculitis can cause single or multiple infracts in the brain

Question 11

List some examples of high grade sarcoma

Answer 11

Clear cell sarcoma 
Dermatofibrosarcoma protuberans
Ewing sarcoma
Extraskeletal myxoid chondrosarcoma
Liposarcoma

Question 12

Describe a systemic wound infection

Answer 12

Systemic infection from a wound affects the body as a whole, with microorganisms spreading throughout the body via the vascular or lymphatic systems.
Systemic inflammatory response, sepsis and organ dysfunction are signs of systemic infection

Question 13

What consequences of SAH tend to occur in the first few days post-bleed

Answer 13

Increased risk of additional ischaemic injury from vasospasm affecting vessels bathed in extravasated blood

Question 14

Which mutations are often seen in melanoma

Answer 14

Mutations that disrupt cell cycle control genes e.g. CDKN2A
Mutations that activate pro-growth signaling pathways e.g. RAS and PI3K/AKT signaling
Mutations that activate telomerase e.g. TERT

Question 15

Why do people in ICU experience weakness and stiffness

Answer 15

Muscles weaken due to long periods of inactivity.

This happens quicker when they are on a ventilator.

Question 16

Why are ICU patient’s at high risk of complications

Answer 16

They will already be severely unwell with most having an issue with one or more organs.
This already makes them vulnerable to complications such as infection and AKI.

Question 17

List the pathological features of secondary haemorrhagic infarcts

Answer 17

The evolution and features of these infarcts are the same as ischemic infarcts
Blood extravasation and resorption will also be seen within them
Extensive intracerebral haematomas may be seen alongside the haemorrhagic infracts if the patient is on anticoagulants

Question 18

How do the ventricles appear in communicating and non-communicating hydrocephalus

Answer 18

Communicating - all 4 ventricles enlarged

Non-communicating - 4th ventricle normal whilst others enlarged
4th normal as CSF can’t flow into is as well due to obstruction

Question 19

What are the two main triggers of DIC

Answer 19

Release of procoagulants into the bloodstream and the injury of endothelial cells.

Question 20

Which cancers are most associated with DIC

Answer 20

Acute promyelocytic leukemia

Adenocarcinomas of the lung, pancreas, colon and stomach

Question 21

If a person is unable to complete a GCS test - e.g. eye opening w/ facial injuries, verbal if intubated- how do you record it

Answer 21

Should be recorded as NT (not testable)

Question 22

Infarcts in focal ischaemic CVA can be divided into which groups

Answer 22

Non haemorrhagic and secondary haemorrhagic infarcts

Question 23

The deficits that are caused by a focal ischemic CVA can improve over time - true or false

Answer 23

True

Due to resolution of local oedema and reversal of injury to the penumbra

Question 24

List common symptoms of cellulitis

Answer 24

Involved site(s): red, hot, swollen, tender
Borders are not elevated or sharply demarcated
Regional lymphadenopathy
Malaise, chills, fever, toxicity

Question 25

Which vessels are most commonly the cause of subarachnoid haemorrhage

Answer 25

Usually arise in arterial bifurcation in circle of Willis

Question 26

What is defined as a high speed RTA

Answer 26

Anything over 30 mph classified as ‘high speed’.

Question 27

List medical management options for raised ICP

Answer 27

Use diuretics (mannitol, hypertonic saline, furosemide, urea) Barbiturate coma Anti-epileptics

Question 28

What causes the contralateral hemiparesis in extradural haematoma

Answer 28

Compression of cerebral peduncle

Question 29

What causes the ipsilateral pupillary dilatation in extradural haematoma

Answer 29

The expanding haematoma causes herniation of uncus of temporal lobe which compresses the pupillary fibres of CN III

Question 30

Which patients are at higher risk of bleeding in reactive gastritis

Answer 30

Those with respiratory failure or coagulopathy

Question 31

List some infections that can cause ARDS

Answer 31

``` Sepsis Diffuse pulmonary infection Viral, mycoplasmic and pneumocystis pneumona Miliary TB Gastric aspiration ```

Question 32

When do watershed infarcts typically occur

Answer 32

Usually occur if the global ischemia is due to severe hypotensive episodes Most commonly seen in patients who have been resuscitated after cardiac arrest.

Question 33

List acute complications of an ICU stay

Answer 33

``` ICU delirium DVT and PE GI ulcers and bleeds Kidney failure Liver damage Pressure ulcers ```

Question 34

What interventions may be performed after a focal ischaemic CVA to reduce the risk of further events

Answer 34

If due to carotid atheromatous plaques then carotid endarterectomy will be done If there is narrowing or occlusion of vessels then angioplasty and stenting can be performed All patients, unless contra indicated, will be placed on either a DOAC or warfarin from 2 weeks following the event

Question 35

List the potential mechanisms of death in DIC

Answer 35

Thrombotic complications such as ischaemia and multi-organ dysfunction Life-threatening haemorrhage due to the consumption of clotting factors

Question 36

What is bazex syndrome

Answer 36

Condition which leads to follicular atrophoderma, multiple basal cell carcinomas, local anhidrosis

Question 37

How does a subdural haemorrhage present

Answer 37

Slowly evolving neurologic symptoms, often with a delay from the time of injury

Question 38

Why can haemoperitoneum go unnoticed

Answer 38

It is bleeding into a free, internal space | May not produce symptoms until they go into hypovolemic shock

Question 39

What causes kidney failure in ICU

Answer 39

Often caused by shock, infection or medication

Question 40

What is the main cause of haemorrhage in the epidural space (extradural)

Answer 40

Trauma | Usually associated with temporal skull fracture in adults - disrupts the middle meningeal artery

Question 41

What is the most common injury type seen in RTAs

Answer 41

``` Blunt force injuries Bruises (external) - e.g. seat belt Contusions (internal) Lacerations - includes flaying Abrasions - includes road rash ```

Question 42

What is the most common cause of wound infection following appendix/biliary surgery

Answer 42

Gram-negative bacilli and anaerobes

Question 43

List some of the late phase (healing) complications of SAH

Answer 43

Meningeal fibrosis and scarring - sometimes causes obstruction of CSF flow as well as interruption of the normal pathways of CSF resorption Survivors also at risk of hydrocephalus

Question 44

How do burns cause DIC

Answer 44

Major trigger is the release of procoagulants such as TF

Question 45

List causes of increased central venous pressure that can lead to raised ICP

Answer 45

Venous sinus thrombosis Heart failure Obstruction of jugular veins

Question 46

List possible symptoms seen in an anterior cerebral artery stroke

Answer 46

``` Disinhibition and speech perseveration Primitive reflexes Altered mental status Impaired judgement Contralateral weakness - greater in arms, Contralateral cortical sensory deficits Gait apraxia Urinary incontinence ```

Question 47

What is the most common cause of wound infection following gastroduodenal surgery

Answer 47

Gram-negative bacilli and streptococci

Question 48

How does a ruptured saccular aneurysms present clinically

Answer 48

Sudden, excruciating headache (“worst headache ever”) - due to blood at high arterial pressure entering SAS Rapid loss of consciousness Neck stiffness + photophobia – meningeal irritation Headache with N+V – raised ICP or meningeal irritation. Confusion, seizures. CN III palsy – posterior communicating artery aneurysm.

Question 49

Describe the effect of endothelial injury in the pathogenesis of DIC

Answer 49

The injury exposes the subendothelial matrix which can activate the platelets and coagulation pathway. This causes thrombi to form due to fibrin deposition.

Question 50

List risk factors for basal cell skin cancer

Answer 50

``` Radiation exposure Gene mutations – TP53 gene mutations in BCC Arsenic exposure through ingestion – Treat asthma and psoriasis Immunosuppression Xeroderma pigmentosum Nevoid basal cell carcinoma syndrome Bazex syndrome Previous nonmelanoma skin cancer Skin type – albinism Rombo syndrome Alcohol consumption Hydrochlorothiazide use – potent photosensitizer ```

Question 51

Which genes have been linked to an increases risk of focal ischaemic CVA

Answer 51

Mutations in F2, F5, NOS3, ALOX5AP and PRKCH

Question 52

Risk of additional ischaemic injury due to extravasated blood is of greatest significance in SAH in which locations

Answer 52

Basal SAH | Vasospasm can involve the major vessels of the Circle of Willis.

Question 53

What is the most frequent cause of spontaneous SAH

Answer 53

Rupture of a saccular (berry) aneurysm | They are found in ~2% of population

Question 54

List the most common causes of DIC

Answer 54

``` Malignancy Sepsis Major trauma Obstetric events Hypoxia, acidosis and shock can all cause endothelial injury and contribute to DIC. ```

Question 55

List the microscopic features of cellulitis

Answer 55

Clusters of neutrophils Invading adipose tissue extensively -> Fat necrosis Seen in deeper tissue

Question 56

List some of the potential complications of haemorrhagic CVA

Answer 56

A large proportion of survivors will be left with some form of neurological deficit which will depend on the site and size of the haemorrhage and therefore the location and extent of damaged tissue It is possible however to have a gradual improvement of the deficits that are left over weeks to months following the event as the haematoma is gradually removed

Question 57

What skin and hair changes may be experienced by ICU patient's

Answer 57

Lots of ICU survivors experience dry skin and hair loss. Usually improves with time

Question 58

What is rombo syndrome

Answer 58

Autosomal dominant condition distinguished by basal cell carcinoma and atrophoderma vermiculatum, trichoepitheliomas, hypotrichosis milia, and peripheral vasodilation with cyanosis

Question 59

List the morphological features of global cerebral ischaemia

Answer 59

The brain will become oedematous and swollen and so the gyri will widen and the sulci will narrow The will be poor demarcation between the white and gray matter on the cut surface. Over time the microscopic features of irreversible ischemic injury will evolve and they mimic the changes in infarcts

Question 60

Which types of basal cell carcinoma will get radiation therapy

Answer 60

Advanced and extended lesion that are not suitable for surgery Can be due to allergy to anesthetics, current anticoagulant therapy

Question 61

List potential differentials for normal pressure hydrocephalus

Answer 61

``` Other forms of dementia Cervical myelopathy All urinary problems Parkinson’s disease Depression Etc. ```

Question 62

List the macroscopic features of basal cell carcinoma

Answer 62

Present as pearly papules containing prominent dilated sub-epidermal blood vessels (telangiectasias) Advanced lesions may ulcerate and cause extensive local invasion of bone or facial sinuses

Question 63

List risk factors for presence of berry aneurysms

Answer 63

Increased incidence in 1st degree relatives. Increased incidence with certain Mendelian disorders - AD PCKD, Ehlers-Danlos type IV, NF1, Marfan’s, fibromuscular dysplasia of extracranial arteries, and coarctation of aorta. Other predisposing factors: cigarette smoking and HTN.

Question 64

Which medical therapies are used for the treatment of high-grade sarcoma

Answer 64

Ifosfamide and doxorubicin-based chemotherapy

Question 65

List causes of haemorrhagic CVA

Answer 65

``` Hypertension Cerebral amyloid angiopathy (CAA) Trauma Aneurysm rupture, Anticoagulation Vasculitis Thrombolysis Coagulopathy Arteriovenous malformations Venous and cavernous angiomas Intracranial neoplasms Cocaine use ```

Question 66

Why do symptoms develop rapidly in an extradural haemorrhage

Answer 66

Rapidly evolving since blood under high arterial pressure is extravasating from the vessel into the potential space between the periosteum and the dura

Question 67

List risk factors for developing HAP

Answer 67

The biggest risk factor is mechanical ventilation - very common in ICU. Also severe underlying disease, immunosuppression, prolonged antibiotics and invasive instrumentation like catheters. All may be seen in ICU

Question 68

What is an extradural haemorrhage

Answer 68

The accumulation of blood in the (potential) space between the periosteal dura and the bone

Question 69

How do you distinguish between focal and global ischaemic brain injury

Answer 69

The distinction between them is not due to pathological differences but rather the amount of brain that is involved.

Question 70

What are the 2 most serious subtypes of brain herniation

Answer 70

Uncal herniation - displacement of the medial part of the temporal lobe (uncus) below the tentorium cerebelli Tonsillar herniation - the cerebellar tonsils are forced downwards through the foramen magnum, causing compression on the brainstem (fatal if left untreated)

Question 71

What happens when the intracranial compensatory mechanisms become exhausted

Answer 71

This is when no further drainage of blood or CSF is possible. At this point, the equilibrium becomes disrupted and the patient enters a decompensated state where intracranial pressure will begin to rise

Question 72

What is the most serious form of skin cancer

Answer 72

Malignant melanoma

Question 73

What is the most common cause of wound infection following orthopedic surgery

Answer 73

S aureus and coagulase-negative staphylococci

Question 74

Describe the pathological features of the vessels in haemorrhagic CVA

Answer 74

Any vessel affected by cerebral amyloid angiopathy will be rigid and therefore will not collapse during processing and sectioning The hyaline material that is deposited in CAA is not made from collagen like it is in normal hyaline arteriosclerosis but rather b amyloid

Question 75

Describe the features of a class 4 - dirty/infected surgical wound

Answer 75

Purulent inflammation present Preoperative perforation of viscera Penetrating traumatic wounds >4 hours

Question 76

List the main complications of raised ICP

Answer 76

Seizures Stroke Neurological damage Death

Question 77

List the macroscopic features of wound infection

Answer 77

Purulent discharge from surgical site or wound or drain placed in the wound Discoloration of tissues both within and at the wound margins Friable, bleeding granulation tissue Lymphangitis - red line spreading from wound

Question 78

What is non-communicating hydrocephalus

Answer 78

Occurs when the flow of CSF is blocked along one or more of the narrow passages connecting the ventricles. Aqueductal stenosis results from a narrowing of the aqueduct of Sylvius, (between the third and fourth ventricles)

Question 79

Describe the natural progression of squamous cell skin carcinoma

Answer 79

If untreated they will destroy nearby healthy tissue | Then spread to the lymph nodes or other organs which can be fatal

Question 80

What is the most common cause of wound infection following head and neck surgery

Answer 80

S aureus, streptococci, anaerobes and streptococci present in an oropharyngeal approach

Question 81

What effect can DIC have on the kidney

Answer 81

The kidneys may have small thrombi in the glomerulus which can lead to reactive swelling, microinfarcts or even bilateral renal cortex necrosis.

Question 82

Steroids improve the outcome in diffuse axonal injury - true or false

Answer 82

False | The make it worse

Question 83

The kidney failure seen in ICU patients is always temporary - true or false

Answer 83

False It can be short-term/temporary in some cases BUT In others it can become a lifelong disease (may need dialysis).

Question 84

Describe the inflammatory phase of wound infection

Answer 84

Begins with coagulation cascade to limit bleeding Platelet reaction & reversible opening of endothelial cell junctions to allow passage of neutrophils and monocytes Inflammatory exudate fills the wound in hours

Question 85

What is brain herniation

Answer 85

A shifting of the brain parenchyma itself in response to high ICP

Question 86

The rate of CSF drainage by a shunt can be altered - true or false

Answer 86

True VP shunts have pressure valve (palpate behind auricle) that can be set with a specially designed magnet/kit. Can be set to drain more or less CSF by changing rate based on patient needs

Question 87

Describe a local wound infection

Answer 87

Local infection is contained in one location, system or structure. Occurs when bacteria or other microbes move deeper into the wound tissue and proliferate at a rate that invokes a response in the host

Question 88

List the potential GCS scores for verbal response

Answer 88

``` 5 – Orientated response 4 – Confused conversation 3 – Inappropriate words 2 – Incomprehensible sounds 1 – No response ```

Question 89

Why might ICU patients end up with longer term breathing issues after their stay

Answer 89

If the patient was on a ventilator their chest muscles will become weaker. May require chest exercises or physio to improve breathing.

Question 90

Describe the pathogenesis of haemorrhagic CVA caused by CAA

Answer 90

Ab peptides are deposited in the walls of medium and small cortical, meningeal and cerebellar vessels Once the vessels walls have amyloid deposited within them it weakens them which makes them more vulnerable to rupture = haemorrhage

Question 91

How does normal pressure hydrocephalus present

Answer 91

Hakim’s triad: abnormal gait, urinary incontinence, dementia

Question 92

Why do babies get massive heads with hydrocephalus

Answer 92

Because their fontanelles haven't fused so the skull can expand to cope with pressure Not seen in adults'

Question 93

Repeat bleeding is common in SAH - true or false

Answer 93

True | prognosis worsens with each bleed

Question 94

How common are CVAs

Answer 94

They are incredibly common Someone in the UK has a CVA every 3.5minutues 15million people suffer a CVA annually worldwide ¼ of individuals in the UK who suffer a CVA will die within a year and >1/2 that survive will be left with a permanent disability

Question 95

Which countries have the highest rates of melanoma

Answer 95

Australia and New Zealand 10-20% arise in the head and neck region Incidence is increasing worldwide though

Question 96

It is common for children to present with a skull # and extradural haemorrhage - true or false

Answer 96

False Children have a deformable skull which means that temporary displacement of skull bones can lacerate underlying vessels without fracture. In adults, a fracture is likely to be seen.

Question 97

What are the most common causative organisms of HAP

Answer 97

Most common organisms are gram +ve cocci (s.aureus) and gram -ve rods (enterobacteriaceae and pseudomonas)

Question 98

Which processes initiate ARDS

Answer 98

ALI/ARDS is initiated by the injury of pneumocytes and pulmonary endothelium It begins a cycle of inflammation and lung damage

Question 99

Squamous cell skin carcinoma is more common in which sex

Answer 99

2-3 times more common in men than women due to higher cumulative lifetime UV exposure

Question 100

What can cause reactive gastritis

Answer 100

The main cases are severe trauma, burns, intracranial disease, major surgery, severe illness and other forms of physiological stress

Question 101

List surgical management options for raised ICP

Answer 101

Surgical decompression Remove mass lesions CSF diversion

Question 102

What are lobar haemorrhages

Answer 102

Haemorrhages that effect the lobes of the cerebral hemispheres Type of haemorrhagic CVA

Question 103

What determines the prognosis of ARDS

Answer 103

Prognosis varies with age of the patient, cause and the number of organs involved. Cause - pneumonia 86% and trauma 38% mortality 3 organs or more is invariably fatal

Question 104

What is communicating hydrocephalus

Answer 104

This is when the flow of CSF is blocked after it exits the ventricles. Called communicating because the CSF can still flow between the ventricles, which remain open

Question 105

What causes a fat emboli

Answer 105

They occur in those that have suffered large fracture | Can also get bone marrow emboli

Question 106

What are the 3 subtypes of reactive gastritis ulcers

Answer 106

Stress ulcers Curling ulcers Cushing ulcers

Question 107

Describe the process of endothelial activation in ARDS

Answer 107

Occurs early on Pneumocyte injury is sensed by the alveolar macrophages which then start to secrete mediators like TNF which act on the nearby endothelium Another mechanism is via circulating inflammatory mediators which activate it directly - occurs in sepsis or systemic illness Some cells will get damaged by the mediators in the process, but others start to express adhesion molecules, procoagulant proteins and chemokines.

Question 108

A GCS score of 8 or below requires which interventions

Answer 108

GCS ≤8 indicates intubation | ICP monitoring where GCS ≤8 w/ abnormal CT head

Question 109

What can cause ARDS

Answer 109

Can be caused by direct lung injury or occur secondary to severe systemic illness Several genes have been linked to ARDS - mostly linked to coagulation or inflammation

Question 110

What effect does an extradural haemorrhage have on the surrounding structures

Answer 110

As it enlarges, it strips the dura from the bone but is restrained at the sutures Gives the convex/lemon shaped appearance

Question 111

Describe the maturation phase of wound infection

Answer 111

Dominant features – wound contraction, scar formation, remodeling

Question 112

Which type of CVA is more common - ischaemic or haemorrhagic

Answer 112

Ischaemic - they account for 82-92% of CVA’s

Question 113

What is the most common cause of ganglionic intracerebral haemorrhage

Answer 113

Hypertension | Associated with deep brain (ganglionic) parenchymal haemorrhages.

Question 114

Where do most berry aneurysms present

Answer 114

90% of saccular aneurysms are near major arterial branch points in the anterior circulation Multiple aneurysms exist in 20-30% of cases

Question 115

What increase the risk of developing ICU delirium

Answer 115

Increased risk from infection, kidney, heart or lung failure and certain drugs. Specific patients will also be at a higher risk: elderly and those with existing memory/cognitive issues.

Question 116

List possible symptoms seen in a vertebrobasilar artery stroke

Answer 116

``` Vertigo Nystagmus Diplopia Visual field defects Dysphagia Dysarthria Facial hypaesthesia Syncope Ataxia ```

Question 117

What can cause an increased production of CSF

Answer 117

Choroid plexus papilloma

Question 118

ICU survivors are two to five times more likely to die compared with age and sex-matched population controls - true or false

Answer 118

True

Question 119

Haemorrhagic CVAs are most common in which age group

Answer 119

They most often occur in mid to late adult life ( peak incidence approx 60yrs)

Question 120

Describe the features of a class 1 - clean surgical wound

Answer 120

``` Uninfected operative wound No acute inflammation Closed primarily Respiratory, gastrointestinal, biliary, and urinary tracts not entered No break in aseptic technique Closed drainage used if necessary ```

Question 121

What are the two main microscopic patterns of basal cell carcinoma

Answer 121

Multifocal superficial type – Multifocal growths originating from the epidermis and sometimes extending Nodular lesions growing downward deeply into the dermis as cords and islands of variably basophilic cells w/ hyperchromatic nuclei, embedded in a mucinous matrix and often surrounded by fibroblasts and lymphocytes

Question 122

List the macroscopic features of cellulitis

Answer 122

Swelling, erythema, warmth Petechiae or hemorrhage Necrotic Involves deeper dermis and subcutaneous fat

Question 123

Describe how the release of TNF can trigger DIC

Answer 123

It causes the endothelial cells to express tissue factor and decrease thrombomodulin expression which tips the balance towards coagulation It also promotes the adhesion of leukocytes (via adhesion molecule expression) which damage the cells. These processes can cause widespread deposition of fibrin within the microvasculature (forms clots)

Question 124

Describe the humoral theory of cerebral blood flow autoregulation

Answer 124

Theory is that it is the action of metabolic by-products that controls flow

Question 125

It is common to see microbleeds in the brains of those with CAA - true or false

Answer 125

True | They have weakened vessels that are prone to rupture

Question 126

ARDS can occur as a result of cardiopulmonary bypass - true or false

Answer 126

True

Question 127

List the most common symptoms of DIC

Answer 127

Microangiopathic anaemia Dyspnoea, cyanosis and respiratory failure Oliguria and acute renal failure Bleeding and bruising – can occur anywhere Convulsions and coma Circulatory collapse and shock

Question 128

What determines the survival of an ischaemic portion of the brain

Answer 128

It will depend on the duration of the ischemia, the magnitude and rapidity of the reduction of blood flow an the presence of collateral circulation These factors also determine the clinical presentation of cerebrovascular disease as they determine the site and size of the damaged area

Question 129

What is the biggest predictor of prognosis in reactive gastritis

Answer 129

How quickly/easily the underlying condition can be treated

Question 130

Describe the treatment of ARDS

Answer 130

No specific treatments for ALI/ARDS Overview - admit to ICU, give supportive therapy and treat the underlying cause. Supportive resp - CPAP or most need careful ventilation Supportive circulation - monitoring and careful fluid management Most need nutritional support Ventilation usually needed at high pressure due to stiffening of the lungs.

Question 131

Which type of CVA do bone marrow emboli typically cause

Answer 131

Focal ischemic CVA | Appears as widespread haemorrhagic lesions in the white matter

Question 132

Describe the typical appearance of a basal cell carcinoma

Answer 132

``` Waxy papules with central depression Pearly appearance Erosion or ulceration, often central Bleeding, especially when traumatized Crusting Rolled (raised) border Translucency Telangiectases over the surface Slow growing (0.5 cm in 1-2 y) ```

Question 133

What is DIC

Answer 133

It is an acute, subacute or chronic thrombohaemorrhagic disorder that is characterised by the excessive activation of the coagulation pathway and the formation of thrombi in the microvasculature

Question 134

What is the main mechanism of death in reactive gastritis

Answer 134

Fatal GI bleeds or the consequences of GI perforation. One study reported a mortality rate of 46% in critically ill patients with GI bleeding, compared with 21% inpatients without bleeding.

Question 135

Describe the pathogenesis of reactive gastritis

Answer 135

Biggest underlying cause is thought to be local ischaemia. This can be caused by systemic hypotension or reduced blood flow caused by stress-induced vasoconstriction of the vessels supplying the GI tract. Redistribution of blood flow occurs in conditions like sepsis In some cases, there is increased release of the vasoconstrictor endothelin-1 which also contributes

Question 136

List some of the complications associated with drains and catheters

Answer 136

Central venous catheters can result in bloodstream infections Urinary catheters have a high risk of causing UTI

Question 137

List the microscopic features of ARDS

Answer 137

Diffuse alveolar damage, interstitial and intra-alveolar damage, inflammation and fibrin deposition are all seen. Inflammation characterised by scattered neutrophils and macrophages Presence of the waxy hyaline membranes in the alveoli - consisting of fibrin-rich oedema and necrotic epithelial cells

Question 138

Describe the role of metabolic autoregulation in the autoregulation of cerebral blood flow

Answer 138

Arterioles dilate in response to chemicals, e.g. lactic acid and CO2

Question 139

What is pulmonary oedema

Answer 139

The presence of excess interstitial fluid within the alveoli It can result from haemodynamic disturbances (cardiogenic) or increased capillary permeability due to microvascular injury (non-cardiogenic).

Question 140

How is the GCS score used

Answer 140

Generally used to categorise traumatic brain injury into mild (13-15), moderate (9-12) and severe (3-8) Part of the APACHE II scoring system, which is used to predict ICU mortality

Question 141

How common are wound infections

Answer 141

A survey sponsored by WHO demonstrated a prevalence of nosocomial infections in the range of 3-21%, with wound infections accounting for 5-34% of the total

Question 142

It is possible to determine whether a CVA is ischemic or haemorrhagic from the clinical presentation alone -true or false

Answer 142

False | Not possible

Question 143

List potential complications of aneurysm clipping

Answer 143

``` Stroke Seizure Vasospasm Bleeding The clip being placed incorrectly so that it does not stop the bleeding or blocks another artery ```

Question 144

List some of the complications associated with tracheostomies

Answer 144

Patients will be unable to speak to begin with which can be distressing. Will leave a scar.

Question 145

What are ganglionic haemorrhages

Answer 145

Haemorrhages effecting the basal ganglia and thalamus | Type of haemorrhagic CVA

Question 146

What is the most common region of the brain to get a focal ischemic CVA due to an emboli

Answer 146

The territory supplied by the middle cerebral artery It is as common for each hemisphere in this territory to be effected

Question 147

How does sepsis cause DIC

Answer 147

Endotoxins released in sepsis can inhibit endothelial expression of thrombomodulin directly or indirectly by stimulating immune cells to make TNF Can also activate factor XII These trigger coagulation Antigen-antibody complexes are also sometimes produced in response to infection and can activate the classic compliment pathway and secondarily activate platelets = coagulation

Question 148

List the consequences of PPI treatment

Answer 148

PPI low incidence of adverse effects or drug interactions.

Question 149

Describe the pathogenesis of a haemorrhagic CVA

Answer 149

Brain tissue is damaged due to a raise in ICP Blood from the ruptured vessels compresses the surrounding tissue causing it to become infarcted. The presence of the blood in the parenchymal tissue and the associated oedema will raise the ICP pressure which will damage the brain tissue The brain also becomes infracted due to a loss of blood supply The blood that is leaking from the ruptured vessels was intended for somewhere so the site it was intended for will become ischemic

Question 150

What is the normal ICP in a newborn

Answer 150

1.5-6 mmHg (often < 0)

Question 151

What are the main causes of subarachnoid haemorrhage

Answer 151

Trauma - typically associated with underlying parenchymal injury. e.g. RTA Vascular abnormality (AV malformation or aneurysm)

Question 152

The onset of DIC is always sudden - true or false

Answer 152

False It can be sudden - e.g. in sepsis However in other cases it can be more insidious and chronic - e.g. in malignancy or dead foetus

Question 153

Describe the myogenic theory of cerebral blood flow autoregulation

Answer 153

Theory is that it is a direct reaction of smooth muscle to the stretch

Question 154

How are surgical wounds classified

Answer 154

Class 1 - clean Class 2 - clean-contaminated Class 3 - contaminated Class 4 - dirty infected

Question 155

Obstruction to CSF flow leads to what

Answer 155

Hydrocephalus | This causes increase ICP

Question 156

Head injury is a common cause of death and disability in RTAs - true or false

Answer 156

True

Question 157

Some cells in the CNS will be more sensitive to ischemia than others - true or false

Answer 157

True Neurones are the most sensitive Astrocytes and glial cells are also particularly sensitive

Question 158

List symptoms of severe cellulitis infections

Answer 158

``` Systemic – violaceous color and bullae Lymphangitic spread, crepitus, hemodynamic instability Cutaneous hemorrhage Skin sloughing Skin anesthesia Rapid progression Gas in the tissue ```

Question 159

Uraemia can cause ARDS - true or false

Answer 159

True

Question 160

Describe how PTCH mutations lead to basal cell carcinoma

Answer 160

PTCH protein is a receptor for sonic hedgehog (SHH), a component of the Hedgehog signaling pathway Typically have a germline loss-of-function mutation in one PTCH allele The second normal allele is inactivated in tumours by an acquired mutation, usually caused by exposure to mutagens (particularly UV light) In this 'off' state PTCH exists in a complex with another transmembrane protein called SMO Binding of SHH to PTCH releases SMO This activates the transcription factor GLI1 which turns on the expression of genes that support tumor cell growth and survival

Question 161

List the pathological features of lacunar infarcts

Answer 161

They are lake shaped, hence the name, <15mm wide and can be single or multiple Microscopically they show gliosis surrounding areas of tissue loss The vessels that are effected can also have a widening of their perivascular spaces which is termed etat crible

Question 162

What is the purpose of craniotomy in haemorrhagic CVA

Answer 162

To remove the collected blood and damaged brain tissue to relive the pressure on the surviving brain Done if bleeds are large

Question 163

Which features of haemorrhagic CVA suggest a poor prognosis

Answer 163

A low GCS suggests a high mortality and poor prognosis A large blood volume at presentation also suggests a poorer prognosis Very large bleeds or bleeds that extend into the ventricular system can be devastating

Question 164

Which age group is most prone to facial cellulitis

Answer 164

adults > 50 yo

Question 165

List complications of shunts for hydrocephalus

Answer 165

Mechanical failure Infections Obstructions

Question 166

Which type of CVA do fat emboli typically cause

Answer 166

Focal ischemic CVA | They tend to cause shower embolisation

Question 167

How can hydrocephalus be classified

Answer 167

As communicating vs non-communicating As congenital vs acquired Or by aetiology

Question 168

List local complications of wound infection

Answer 168

Delayed and non-healing of wound | Abscess formation

Question 169

How do CVAs caused by fat emboli typically present

Answer 169

Present with generalised cerebral dysfunction, a lack of localising signs and disturbances of higher cortical function

Question 170

Describe the neurogenic theory of cerebral blood flow autoregulation

Answer 170

Theory is that it is the action of perivascular nerves that controls flow

Question 171

List potential causes of pulmonary oedema due to undetermined origin

Answer 171

High altitude | Neurogenic - CNS trauma

Question 172

List the microscopic features of melanoma

Answer 172

Cells are usually larger than normal melanocytes They have enlarged nuclei with irregular contours and chromatin clumped at periphery of nuclear membranes Prominent red nucleoli (eosinophilic)

Question 173

ICP is determinant of cerebral perfusion pressure - true or false

Answer 173

True | CPP = MAP – ICP

Question 174

List the macroscopic features of melanoma

Answer 174

Striking variations in color, appearing in shades of black, brown, red, dark blue and gray Zones of white or flesh-colored hypopigmentation appear on occasion due to focal regression Irregular and notched border Radial growth – horizontal spread of melanoma within the epidermis and superficial dermis Vertical growth phase – is often heralded by the appearance of a nodule

Question 175

What is the GCS scored out of

Answer 175

15 eyes out of 4 verbal response out of 5 motor response out of 6

Question 176

Which parts of the brain may be involved in a intra-parenchymal brain haemorrhage

Answer 176

Selective involvement of the crests of gyri, where the brain is in contact with the inner surface of the skull (frontal & temporal tips, orbitofrontal surface) Petechial haemorrhages in an area of previously ischaemic brain, usually following the cortical ribbon. “Lobar” haemorrhage involving subcortical white matter and often with extension into the SAS. Centred in the deep white matter, thalamus, basal ganglia, or brainstem; may extend into the ventricular system.

Question 177

List common ICU interventions/devices that often lead to complications

Answer 177

``` Ventilators Tracheostomy IV lines and pumps Feeding tubes Drains and catheter Drugs ```

Question 178

What is ICP

Answer 178

The intracranial pressure It is the pressure within the cranium of the skull It is measured in millimeters of mercury mmHG

Question 179

What determines the extent of a focal ischaemic CVA

Answer 179

The duration of the ischemia and the extent of collateral blood supply This also determines the size, location and shape

Question 180

List the macroscopic features of reactive gastritis

Answer 180

Lesions range from shallow erosions to ulcers that penetrate the gastric mucosa. The ulcers are typically rounded, under 1cm in diameter and usually have a black/brown base due to staining by the acid digesting blood products. These lesions are found anywhere in the stomach and usually occur in multiples.

Question 181

What are the 3 main injury categories in RTA

Answer 181

Acceleration/ deceleration (may occur even w/out an impact) 1 impact w/ vehicle 2 impact w/ road or stationary object

Question 182

How do you treat wound infection

Answer 182

Antibiotic prophylaxis Each surgical specialty, body region and operation type needs to have its strategy to treat due to different microbial spectrum Early surgical debridement - however, re-opening of surgical site can cause significant morbidity Sepsis Treatment – antibiotics

Question 183

Where do most basal cell carcinomas occur

Answer 183

Occurs mostly on face, head and neck, and hands

Question 184

Which organisms commonly cause wound infection

Answer 184

Patient's own endogenous flora | e.g. staphylococci (S.aureus strain is most common), MRSA, streptococci, enterococci

Question 185

List the macroscopic features of non-haemorrhagic infarcts

Answer 185

There will not be much change in their appearance in the first 6 hrs of irreversible injury The tissue will be soft, swollen and pale and the gray-white matter junction will become indistinct by 48hrs Between 2-10 days - The brain will become friable and gelatinous As oedema resolves in the viable adjacent tissue the ill defined border between infracted and normal tissue will become defined The tissue will then liquefy which will eventually leave a cavity that is filled with fluid which c will keep expanding until all dead tissue has been cleared. This occurs from day 10 and lasts for 3 weeks

Question 186

List the clinical features of high-grade sarcoma

Answer 186

Gradually enlarging painless mass Can become quite large, esp. in thigh and retroperitoneum Pain or symptoms associated with compression by the mass – paresthesias or edema in an extremity Constitutional symptoms rarely – fever and/or weight loss

Question 187

Which systemic factors can increase the risk of wound infection

Answer 187

``` Age Malnutrition Hypovolemia Poor tissue perfusion Obesity Diabetes Steroids and other immunosuppressants ```

Question 188

What would happen if a brain tumour continued to grow without intervention

Answer 188

The intracranial pressure will rise to such a degree that the final cranial component, the brain parenchyma, will shift in position and become displaced, this is termed herniation

Question 189

Which operative characteristics can increase the risk of wound infection

Answer 189

``` Poor surgical technique Lengthy operation Intraoperative contamination Prolonged preoperative stay in the hospital Hypothermia ```

Question 190

List some acceleration/deceleration injuries than may be seen in RTA

Answer 190

Diffuse axonal injury - caused by shearing forces on brain Aortic dissection - shearing forces generated by arch of aorta continuing forward whilst descending aorta anchored to thoracic spine

Question 191

How does hydrocephalus affect the surrounding brain tissue

Answer 191

The excess fluid increases the size of the ventricles and puts pressure on the brain. This can damage brain tissues and cause a range of impairments in brain function.

Question 192

Describe the structure of the pia mater

Answer 192

Adherent to the brain parenchyma and spinal cord. | Thin and highly vascularised - helps nourish the underlying neural structures

Question 193

Describe the typical appearance of a squamous cell carcinoma of the skin

Answer 193

Preceded by actinic keratoses | A shallow ulcer with heaped-up edges, covered by a plaque

Question 194

Which organisms are the most common of cellulitis from bite wounds

Answer 194

``` Capnocytophaga canimorsus (dog) Eikenella corrodens (human) Pasteurella multocida (dog or cat) Streptobacillus moniliformis (rat) ```

Question 195

What causes berry aneurysms

Answer 195

Aetiology is unknown but absence of SM and intimal elastic lamina in affected vessel suggests that they are developmental abnormalities.

Question 196

When might you see burns in a RTA

Answer 196

May see if vehicle catches fire but unlikely in RTCs otherwise

Question 197

List the complications of TPA treatment used in focal ischaemic CVAs

Answer 197

``` Haemorrhagic CVA Hypotension Fluid accumulation on the brain Pericarditis Cardiac tamponade Arrhythmia Heart failure Fluid accumulation in the lungs Seizures Swelling of the vocal cords Internal bleeding ```

Question 198

List potential causes of haemodynamic pulmonary oedema

Answer 198

``` Left-sided heart failure Volume overload Pulmonary vein Hyperalbuminemia Kidney (nephrotic or protein-losing enteropathies) and liver disease Infections - e.g. bacterial pneumonia Lung trauma Liquid aspiration Inhales gases - ```

Question 199

Which masses can lead to an increase in ICP

Answer 199

``` Tumour Infarct Contusions Haematoma Abscess ``` They distort surrounding brain by increasing pressure

Question 200

Hypersensitivity reactions to what substances can cause ARDS

Answer 200

Drugs | Organic solvents

Question 201

How common is reactive gastritis in ICU patients

Answer 201

Most patients admitted to ICU will have some histological evidence of gastric mucosal damage. In 1-4% of these patients, the bleeding is so severe that transfusions are required.

Question 202

What exacerbates the cyanosis and hypoxaemia in ARDS

Answer 202

They are exacerbated by the V/Q mismatch - occurs because some areas affected and some not

Question 203

What causes a stress ulcer in reactive gastritis

Answer 203

Most common in sepsis, shock or severe trauma

Question 204

What are the two main types of CVA

Answer 204

Ischaemic and haemorrhagic

Question 205

What is the main cause of subdural haemorrhage

Answer 205

Trauma | May follow minor trauma - particularly in elderly

Question 206

What is the most common site of metastases in high-grade sarcoma

Answer 206

Lung

Question 207

DVT/PE prophylaxis is recommended for all ICU patients - true or false

Answer 207

true

Question 208

What is the only definitive treatment for DIC

Answer 208

Treat the underlying cause

Question 209

List some chemical injuries that can cause ARDS

Answer 209

Heroin or methadone overdose Acetylsalicylic acid - aspirin Barbiturate overdose Paraquat

Question 210

Describe the mechanism through which the CNS tissue is damaged in a CVA

Answer 210

As the blood flow becomes reduced the neurones will cease functioning Once the cells become ischaemic they will have a reduction of ATP as they can no longer complete oxidative phosphorylation due to a lack of O2. This reduction of ATP leads to cell and organelle swelling which causes cell death through necrosis The ischemia will also cause an inappropriate release of glutamate which will further damage neurones by causing an influx of Ca ions into them (excitotoxicity) It also though that some of the cells in a CVA die through apoptosis

Question 211

What is the Monroe-Kellie doctrine

Answer 211

It describes the relationship between the contents of the cranium and intracranial pressure The increased volume of any of the contents leads to a decrease volume of one or both of the others

Question 212

What is wound contamination

Answer 212

Wound contamination is the presence of non-proliferating microbes within a wound at a level that does not evoke a host response

Question 213

Describe the pathogenesis of high grade sarcoma

Answer 213

Start with genetic mutations - e.g. loss of function of tumour suppressor gene like p53 Soft-tissue tumours grow centripetally They will reach anatomic limits and then breach compartmental boundaries This allows them expand more quickly due to a lack of fascial boundaries Peripheral portion of the tumor compresses surrounding soft tissue which leads to formation a well-defined compression zone of fibrous tissue & inflammatory cells The reactive zone surrounding it together form a pseudocapsule that encloses the tumor Will eventually progress to metastatic disease

Question 214

Describe the role of CO2 in the autoregulation of cerebral blood flow

Answer 214

CO2 is a potent dilator! Increased CO2/increased BP → vasodilation Decreased CO2/decreased BP → vasoconstriction

Question 215

Which type of intracranial haemorrhage appears in a crescent moon shape on CT/MRI

Answer 215

Subdural

Question 216

Which cells in the brain are most sensitive to ischaemia

Answer 216

Neurones are the most sensitive Astrocytes and glial cells are also particularly sensitive The most sensitive neurones to ischemia, and therefore the neurones that are damaged first in these events, are; the pyramidal neurones in the hippocampus, cerebellar purkinje cells and pyramidal neurones in the cerebral cortex ( especially the ones in layers 3 and 5).

Question 217

What is the most common cause of lobar intracerebral haemorrhage

Answer 217

Cerebral amyloid angiopathy

Question 218

What are the main types of vascular disease that cause focal ischemic CVAs

Answer 218

Emboli from distant sites Thrombosis within cerebral vessels Other vasculidites

Question 219

How common is DVT in ICU patients

Answer 219

Prevalence of about 30%.

Question 220

List common injury patterns

Answer 220

``` Blunt force - bruises, lacerations, abrasions Sharp force - incisions and stabs Gunshot Burns - heat, electrical chemical Head injuries ```

Question 221

What is Terson syndrome

Answer 221

Vitreous haemorrhage associated with SAH

Question 222

Describe the path of CSF flow

Answer 222

Secreted from the choroid plexus in the lateral ventricles It flows through the ventricle system to the subarachnoid space (Magendie and Luschka) This then enters the venous system through the arachnoid granulations

Question 223

List risk factors for developing cellulitis

Answer 223

High risk: Elderly, diabetes Post-surgery Varicella infection - cellulitis can complicate varicella MRSA Bite wounds, lacerations and puncture wounds

Question 224

What is normal pressure hydrocephalus

Answer 224

A chronic idiopathic condition (accumulation of CSF) commonly seen in the elderly

Question 225

Which countries have the highest rates of basal cell carcinoma

Answer 225

Affect countries near equator | Highest rates occur in South Africa and Australia, areas that receive high amounts of UV radiation

Question 226

How can genetics impact the development of squamous cell skin cancer

Answer 226

Sporadic tumours will have acquired defects (also seen in their precursors) e.g. loss of p53 function These defects also have a relationship with the damage caused by sun exposure

Question 227

When is radiation used in the treatment of high grade sarcoma

Answer 227

If the patient refuses or cannot tolerate surgery

Question 228

Which gene is associated with Nevoid basal cell carcinoma syndrome (NBCCS)

Answer 228

PTCH – a tumour suppressor gene Typically have a germline loss-of-function mutation in one PTCH allele The second normal allele is inactivated in tumours by an acquired mutation, usually caused by exposure to mutagens (particularly UV light) This leads to the cancer

Question 229

What innervates the dura mater

Answer 229

Innervation from CN V Pain in meningitis is from stretching of dura detected by CV V

Question 230

What are the main causes of the cardiac mural thrombi

Answer 230

``` MI AF Valvular disease - mitral stenosis, prosthetic valves, endocarditis Severe heart failure Dilated cardiomyopathy ```

Question 231

Which parts of the body may strike the interior of the car in an RTA

Answer 231

Head = Windscreen/ window/ front pillar May cause injury such as skull fracture, cerebral haemorrhage or contusions etc. Chest +/- abdomen =- Dashboard/ door May cause injury such as rib fractures, pulmonary contusions, splenic and hepatic lacerations etc. Lower body = Car body or chassis May cause injury such as leg/femur fractures etc.

Question 232

Why is the incidence of wound infection likely underestimated

Answer 232

Most wound infections occur when the patient is discharged, and these infections may be treated in the community without hospital notification

Question 233

How do you manage reactive gastritis

Answer 233

Main management is treating the underlying condition. PPI or H2 receptor antagonist can be given prophylactically to lessen the impact of gastric ulceration in high-risk patients.

Question 234

Describe the pathogenesis of lacunar infarcts

Answer 234

Due to the Hx the effected vessels develop arteriosclerosis (which is also called small vessel disease because it effects vessels between 40-900um in diameter) The disease can then progress to cause thrombosis and complete vessel occlusion which will ultimately lead to cavitary infarcts known as lacunar infracts

Question 235

Describe the pathological features of ganglionic intracerebral haemorrhage caused by HTN

Answer 235

Vessel wall abnormalities including accelerated atherosclerosis in larger arteries, hyaline arteriosclerosis in smaller arteries, and (if severe) proliferative changes + frank necrosis of arterioles. The arterioles with hyaline change are thickened and more vulnerable to rupture

Question 236

When is chemotherapy used in the treatment of high grade sarcoma

Answer 236

Can be used as medical treatment | Also used to reduce the risk of metastatic disease following multimodality treatments without amputation

Question 237

Which age groups are more likely to get cellulitis

Answer 237

A higher incidence of cellulitis in individuals older than 45 years More common in geriatric patients Certain age groups are at higher risk in some unique scenarios (e.g. children)

Question 238

Describe the structure of the arachnoid mater

Answer 238

Directly under dura, contains connective tissue and is avascular. CSF contained in space under arachnoid mater, the subarachnoid space. Arachnoid granulations are small projections of arachnoid membrane into dura venous sinuses that allow CSF to re-enter venous circulation

Question 239

List the morphological features of diffuse axonal injury

Answer 239

Widespread, often asymmetric, axonal swellings that appear within hours of injury and can persist for much longer. Swelling best seen using silver impregnation techniques or with immune-peroxidase stains for axon transport proteins, e.g., amyloid precursor protein and alpha-synuclein May also see focal haemorrhagic lesions Later, increased number of microglia seen in damaged areas of cerebral cortex, and subsequently there is degeneration of the involved fibre tracts.

Question 240

What is an ischaemic CVA

Answer 240

Impairment of blood supply and oxygenation of the CNS tissue which results in ischemia and hypoxia of the brain tissue. They can either be global or focal

Question 241

What causes mesenteric bruising in RTA

Answer 241

Can occur when seatbelts are worn due to position of lap belts Causes compression of closed bowel loops and mesenteries between impacting surface and spine

Question 242

What is the incidence of ARDS in ICU units

Answer 242

A 2016 study found it to be 10.6%

Question 243

How does UVB radiation cause melanoma

Answer 243

Cause multiple genetic changes which leads to malignant transformation of melanocytes

Question 244

Describe the microscopic appearance of a saccular (berry) aneurysm

Answer 244

The arterial wall adjacent to aneurysm neck shows some intimal thickening + attenuation of the media. Smooth muscle and intimal elastic lamina do not extend into the neck and are absent from the aneurysm sac itself – made up of thickened hyalinised intima and an adventitia covering.

Question 245

Haemorrhagic CVA has a higher mortality than ischemic CVA - true or false

Answer 245

True | Although they are less common

Question 246

How can systemic acidosis lead to reactive gastritis

Answer 246

It alters the intracellular pH of the gastric mucosal cells and disrupts the pH gradient that usually promotes the wash-out of acid

Question 247

List the microscopic features of healed focal ischaemic infarcts

Answer 247

The astrocytic response will recede after several months which will leave a dense network of glial fibres admixed with new capillaries and perivascular connective tissue A gliotic layer of tissue separates the cavity from the meninges and subarachnoid space

Question 248

List causes of brain swelling that can lead to raised ICP

Answer 248

``` Ischaemia/anoxia Acute liver failure Encephalopathy, Idiopathic intracranial hypertension Hypercarbia ``` These all decrease CPP, but cause minimal tissue shift

Question 249

Which causes, other than atheromatous plaques, | should be considered in young patients with thrombosis causing focal ischemic CVA

Answer 249

``` Antiphospholipid syndrome Protein C and S deficiency Pregnancy Sickle cell disease Cocaine and amphetamines ```

Question 250

Where do most squamous cell skin carcinomas occur

Answer 250

70% occur on head and neck

Question 251

What are the most common patterns of intracerebral haemorrhages

Answer 251

Ganglionic May originate in putamen (50-60%), thalamus, pons, cerebellar hemispheres (rare), and other brain regions Lobar Occurs in small- and medium- calibre leptomeningeal, cortical and cerebellar vessels.

Question 252

List the clinical signs seen if a haemorrhagic CVA occurs in the cerebellum

Answer 252

``` Facial weakness Ipsilateral ataxia Gaze paresis Sensory loss Skew deviation Miosis Deceased conscious level ```

Question 253

List potential complications of craniotomy

Answer 253

``` Seizure Stroke Brain swelling CSF leak Nerve damage Loss of some mental function ```

Question 254

What is the main complication of DVT in ICU

Answer 254

Can lead to a PE

Question 255

What is a haemorrhagic CVA

Answer 255

These are when the tissue infarction is due to rupture of a parenchymal vessel meaning areas of tissue are no longer supplied with blood It also results in bleeding into the brain parenchyma

Question 256

Trauma to the pterion commonly cause which type of intra-cranial haemorrhage

Answer 256

Extradural

Question 257

List potential complications of mannitol treatment

Answer 257

``` Arrhythmia Hypotension Pulmonary congestion Acidosis Skin necrosis Convulsion Anaphylaxis ```

Question 258

How can you diagnose raised ICP

Answer 258

Medical history and physical exam including a neurological exam to test senses, balance and mental status LP - measures the pressure of CSF CT head - GOLD standard MRI - shows more detail

Question 259

Why might a stay in ICU lead to liver damage

Answer 259

May become damaged as a side effect of medications used to treat other important conditions. Also at risk due to shock, infection etc.

Question 260

Describe a Cushing ulcer in reactive gastritis

Answer 260

Can be gastric, duodenal or oesophageal and typically arise in those with intra-cranial disease Has an increased risk of perforation

Question 261

What is the most common cause of lobar haemorrhages

Answer 261

The main cause of these is cerebral amyloid angiopathy (CAA)

Question 262

List the microscopic features of acute focal ischaemic infarcts (first 48hrs)

Answer 262

Eosinophilic neuronal necrosis (“dead red neurones”) will be seen in the neurones in the effected area. ( 6-12hrs) Vasogenic and cytotoxic oedema will both be present (6-12hrs) The normal tinctorial characteristics of gray and white matter structures will be lost (6-12hrs) Myelinated fibres will disintegrate and glial cells, predominantly astrocytes, and endothelial cells will swell (6-12hrs) There will be progressive neutrophilic emigration which will eventually drop of (which is never as prominent as it s following an MI) ( up to 48hrs)

Question 263

What is reactive gastritis

Answer 263

This is a type of gastritis that occurs in the context of severe trauma, burns, intracranial disease, major surgery, severe illness and other forms of physiological stress

Question 264

In the absence of pathology, normal homeostatic mechanisms maintain a normal intracranial pressure - true or false

Answer 264

True | They respond to small fluctuations in intracranial volume

Question 265

Where in the saccular aneurysm does rupture usually occur

Answer 265

Rupture usually occurs at apex of sac | Blood goes into the SAS, the brain substance, or both.

Question 266

Describe the structure of the dura mater

Answer 266

Lies directly beneath skull or vertebral column. It is the thickest and toughest (fibrous) layer. In skull there are 2 layers - periosteal (outmost) and meningeal (innermost) The dural venous sinuses are enclosed between the layers The layers also form the dural septae when they separate - falx cerebri and tentorium cerebelli etc. In spine: meningeal part only.

Question 267

What is the most common site of melanoma

Answer 267

10-20% arise in the head and neck region

Question 268

What is the most common cause of ganglionic haemorrhages

Answer 268

The major cause is hypertension

Question 269

List the clinical signs seen if a haemorrhagic CVA occurs in the caudate nucleus

Answer 269

Confusion Contralateral hemiparesis Conjugate gaze paresis

Question 270

How does ICU delirium present

Answer 270

May present with hallucinations, confusion, may not recognise surroundings or people, difficulty remembering or understanding information As per normal delirium you get hyperactive and hypoactive forms Usually temporary and last days/weeks, some use meds to treat but not well supported

Question 271

When would extensive intracerebral haematomas be seen alongside secondary haemorrhagic infracts

Answer 271

If the patient is on anticoagulants

Question 272

List the clinical signs seen if a haemorrhagic CVA occurs in the thalamus

Answer 272

``` Contralateral sensory loss and hemiparesis Homonymous hemianopia Gaze paresis Miosis Confusion Aphasia ```

Question 273

What is the most common cause of wound infection following urology procedures

Answer 273

Gram-negative bacilli

Question 274

Describe the transformation of a non haemorrhagic to secondary haemorrhagic infarct

Answer 274

It is called secondary haemorrhagic transformation You only get this transformation of the initial causative event lasted long enough to damage the small blood vessels in the effected area as it is there damage that allows the haemorrhage into the infarct when reperfusion occurs The haemorrhages in these infarcts are usually petichiael but can be multiple or confluent

Question 275

List some of the complications associated with IV lines and pumps

Answer 275

Associated with bruising and sometimes even scars. Infection risk.

Question 276

What effect can DIC have on the lungs

Answer 276

Many fibrin thrombi can be seen in the alveolar capillaries. May be associated with pulmonary oedema and fibrin exudation which forms the hyaline membranes.

Question 277

Describe the macroscopic appearance of a saccular (berry) aneurysm

Answer 277

thin-walled outpouching usually on an arterial branch point along the circle of Willis, or a major vessel just beyond Few mm to 2-3cm in diameter Bright red, shiny surface and a thin, translucent wall. Atheromatous plaques, calcification or thrombi may be found in the wall or lumen of the aneurysm. Sometimes there is evidence of prior haemorrhage - brownish discolouration of adjacent brain and meninges Neck of aneurysm may be wide or narrow.

Question 278

Describe the clinical features of global cerebral ischaemia

Answer 278

The clinical outcome in these cases will vary depending on the insult's severity and length If it is only a mild case then the patient may only have a transient post-ischemic confusional state followed by a complete recovery Unfortunately it is also possible for the patient to be left with irreversible CNS damage

Question 279

What is the definition of cerebrovascular accident

Answer 279

This is when there is tissue infarction in the brain as a consequence of altered blood flow

Question 280

How do you calculate cerebral blood flow

Answer 280

Cerebral perfusion pressure divided by cerebral vasc resistance

Question 281

How does ARDS progress

Answer 281

Symptoms appear rapidly and then the patient will progress to respiratory failure.

Question 282

List the three main causes of CSF flow problems

Answer 282

Obstruction - obstructive hydrocephalus Increased production Decreased absorption - communicating hydrocephalus

Question 283

Describe the features of a class 2 - clean-contaminated surgical wound

Answer 283

Elective entry into respiratory, biliary, gastrointestinal, urinary tracts and with minimal spillage No evidence of infection or major break in aseptic technique Example: appendectomy

Question 284

What effect do the clots have in DIC

Answer 284

They can cause ischaemia of affected or vulnerable organs by occluding the vessels It also leads to a microangiopathic anaemia as the red cells fragment as they try to squeeze through the occluded vessels

Question 285

How do you differentiate reactive gastritis from chronic gastritis

Answer 285

In reactive gastritis the scarring and blood vessel thickening that is typically seen with chronic gastric ulcers is absent.

Question 286

Describe the pathological features of invasive squamous cell carcinoma

Answer 286

Nodular, variable keratin production (appreciated grossly as hyperkeratotic scale), may ulcerate Shows variable degrees of differentiation

Question 287

What are the 3 main types of intracranial haemorrhage

Answer 287

Subarachnoid, intracerebral, extradural

Question 288

What proportion of ICU patients will develop AKI

Answer 288

50%

Question 289

How common are long-term mental health effects after ICU stay

Answer 289

In one study of survivors of acute lung injury, 36% were found to have depression, about 40% anxiety, and 62% PTSD Unsurprising as it is a very traumatic experience for both patient and family

Question 290

Which part of the brain is most affected in diffuse axonal injury

Answer 290

Affect central areas: brainstem (95%; immediate death), corpus callosum, parasagittal areas, interventricular septum, hippocampal formation Brain has different areas of mass and densities, when pressure or shearing forces are applied these areas will move/strain with different force. Occurs where density difference is greatest (grey/white interface).

Question 291

How do you differentiate reactive gastritis from normal peptic ulcers

Answer 291

Reactive gastritis ulcers can be found anywhere in the stomach and usually occur in multiples Normal peptic ulcers are usually solitary and found in the antrum

Question 292

Which types of haemorrhagic CVA are usually due to underlying cerebrovascular disease

Answer 292

Haemorrhages in the brain parenchyma and the subarachnoid space

Question 293

How do you treat hydrocephalus

Answer 293

Usually surgical treatment to restore and maintain normal cerebrospinal fluid levels in the brain - shunts etc.

Question 294

What is the main management of focal ischaemic CVA

Answer 294

The gold standard is IV TPA within 4.5hrs of symptoms starting If the cause is a particularly large clot them embolectomy may be performed to remove it

Question 295

Hydrocephalus is most common in which age groups

Answer 295

Occurs more frequently among infants and adults 60 and over

Question 296

List the delayed compensatory mechanisms for rising ICP

Answer 296

Decrease in extracellular fluid

Question 297

What is the definition of stroke

Answer 297

This is the clinical term for a CVA and it is defined as the acute onset of neurological symptoms that last >24hrs and can be explained by a vascular mechanism

Question 298

Which types of haemorrhagic CVA are usually due to trauma

Answer 298

Epidural and subdural haemorrhages

Question 299

Which regions of the brain are most sensitive to ischaemia

Answer 299

The border/watershed regions where to ends of an arterial supplies territory meet. The border between the anterior and middle cerebra hemispheres is the most at risk of these areas in the cerebral hemispheres in these events These areas will be damaged first in global ischaemia

Question 300

What is the normal ICP for an adult

Answer 300

7–15mmHg

Question 301

Hypertension related intraparenchymal haemorrhages typically originate in which part of the brain

Answer 301

The putamen, thalmus, cerebellar hemispheres, pons or other regions of the brain

Question 302

What is xanthochromia

Answer 302

Yellow CSF Seen in SAH CSF would initially be blood-tinged from SAH but the delay allows the blood to be broken down into haem then bilirubin = yellow

Question 303

Mucus from some adenocarcinomas can act as a procoagulant - true or false

Answer 303

True | In some cases it can activate factor X and aid coagulation

Question 304

High-grade sarcomas tend to invade locally - true or false

Answer 304

True | They will have ill-defined margins as a result

Question 305

Which signs are more common in patients with haemorrhagic CVAs than patients with ischemic CVAs

Answer 305

Headache, altered mental status, seizures, marked Hx and nausea and vomiting With the exception of the Hx this is due to the fact that these signs are caused by raised ICP which is more of a feature in haemorrhagic CVA

Question 306

List some of the complications of high grade sarcoma

Answer 306

``` Skin ulceration Thrombocytopenia Hemorrhage Fracture (depending on histopathologic category and anatomic site) ```

Question 307

What determines the risk of saccular aneurysm rupture

Answer 307

Most frequent in 5th decade (slightly F>M) Risk of rupture depends on size and location of aneurysm :(<7mm is low risk and posterior circulation is higher risk) FH and co-morbidity (e.g. PCKD or HTN) 1/3 cases are associated with acute increases in intracranial pressure e.g., straining with stool

Question 308

How does haemorrhage in the epidural space present (extradural)

Answer 308

Often have a brief LOC followed by short lucid period (regain consciousness and awareness) Patient will then deteriorate and exhibit symptoms e.g., headache, vomiting, contralateral hemiparesis & ipsilateral pupillary dilatation Rapidly evolving neurologic symptoms that require intervention.

Question 309

Describe the process of neutrophil adhesion and in ARDS

Answer 309

Neutrophils will adhere to the molecules expressed by the endothelium and migrate into the interstitium and alveoli They degranulate and release many inflammatory mediators such as proteases, cytokines, ROS, neutrophil epithelial traps - directly injure lung This starts the lung inflammation associated with ARDS

Question 310

Where do most melanomas occur

Answer 310

Occurs mostly on the trunk in white males and lower legs and back in white females

Question 311

List risk factors for DVT in ICU

Answer 311

Associated with increased duration of ventilation and longer ICU stay. Longer they are in ICU the longer they are immobile = higher DVT risk Some patients are more at risk: cancer, infections, trauma or genetics.

Question 312

Cerebrovascular disease is the most prevalent cause of mortality and morbidity from neurologic disease in the US - true or false

Answer 312

True | It is also the fifth leading cause of death in the US

Question 313

What is the definition of Transient Ischemic Attack

Answer 313

This is when the clinical signs of a CVA last < 24Hrs

Question 314

What is the most common cause of wound infection following obs/gynae surgery

Answer 314

Gram-negative bacilli, enterococci, anaerobes, group B streptococci

Question 315

If the protective functions of p53 are lost, how does the body deal with DNA damaged by UV

Answer 315

Loss of protective functions of p53 DNA damage induced by UV light is repaired by error-prone mechanisms This leads to rapid accumulation of mutations & carcinogenesis This creates mutations that are passed down to daughter cells = cancer

Question 316

ARDS is associated with which lifestyle factors

Answer 316

More common and worse in chronic alcoholics and smokers

Question 317

What are some of the risk factors for long-term cognition issues after ICU stay

Answer 317

delirium, hypotension, hypoxemia, prolonged sedation, and hypoglycemia

Question 318

How do you treat cellulitis

Answer 318

Oral or IV penicillin (drug of choice for initial treatment) unless patient has known penicillin allergy Antifungal medications if necessary Warm soaks to the site to help relieve pain and decrease edema by increasing vasodilation Pain medication is needed Elevation of infected extremity Can be treated as outpatient with oral therapy but some do require admission and IV antibiotics

Question 319

Where in the cerebral vessels are emboli most likely to lodge

Answer 319

At sites where vessels branch or sites where there is already luminal narrowing

Question 320

List systemic complications of wound infection

Answer 320

Cellulitis Osteomyelitis Septicemia – Death (distant hematogenous spread of bacteria and sepsis)

Question 321

Which type of intracranial haemorrhage appears in a bi-convex, ‘lemon-shaped’ area on CT/MRI

Answer 321

Extradural | May also see mass effect & brain herniation

Question 322

How do you treat squamous cell skin carcinoma

Answer 322

Electrodessication and Curettage – treat localized, superficial lesion Surgical excision Radiation therapy Systemic treatment – chemotherapy, immunotherapy

Question 323

How can cellulitis progress to a more serious illness

Answer 323

Uncontrolled contiguous spread (lymphatic or circulatory systems)

Question 324

What effect can DIC have on the CNS

Answer 324

The thrombi can cause microinfarcts which result in carrying neurological symptoms

Question 325

How can intracerebral haemorrhage cause secondary infarction

Answer 325

The collection of blood compresses the adjacent parenchyma | The compression causes secondary infarction

Question 326

Why does the brain have high O2 requirements

Answer 326

The brain needs a constant supply of energy and it gets this energy through aerobic metabolism

Question 327

What are the goals of therapy in raised ICP

Answer 327

Maintain CPP | Prevent ischaemia and brain compression

Question 328

List causes of intra-parenchymal brain haemorrhage

Answer 328

Trauma -contusions Ischaemia -haemorrhagic conversion of an ischaemic infarct Cerebral amyloid angiopathy (CAA)  Hypertension Tumours -primary or metastatic Associated with high-grade gliomas or certain metastases (melanoma, choriocarcinoma, RCC).

Question 329

What is the most common cause of squamous cell skin carcinoma

Answer 329

DNA damage induced by exposure to UV light | Tumour incidence is proportional to the degree of lifetime sun exposure

Question 330

What is the main determinant of prognosis in DIC

Answer 330

The underlying condition | The prognosis varies greatly between patients

Question 331

How long does it take neurological symptoms of a focal ischaemic CVA to appear

Answer 331

The neurological deficits usually develop over minutes but can progress and develop over several hours

Question 332

Pancreatitis can cause ARDS - true or false

Answer 332

True

Question 333

List some of the complications associated with medications on ICU

Answer 333

All come with their own side effects One example would be certain antibiotics causing a C.diff infection Also have to consider drug interactions

Question 334

Describe the pathological features of in-situ squamous cell carcinoma

Answer 334

They appear as sharply defined, red, scaling plaques | Cells with atypical nuclei involve all levels of epidermis

Question 335

What are the clinical features of reactive gastritis

Answer 335

The most common sign is actually the GI bleeding | This may present as haematemesis, melena and/or coffee ground vomit.

Question 336

How common is ICU delirium

Answer 336

Also 60-80% ventilator patients will develop delirium.

Question 337

Describe the pathogenesis of cellulitis

Answer 337

Usually follows a breach in the skin e.g. fissure, cut, laceration, insect bite or puncture wound In some cases: no obvious portal of entry; may be due to microscopic changes in the skin or invasive qualities of certain bacteria Organisms on skin & its appendages gain entrance to the dermis and multiply leading to cellulitis Contamination -> Colonization -> Infection

Question 338

How can inflammation lead to focal ischaemic CVA

Answer 338

If there is an inflammatory process in a blood vessel it can cause luminal narrowing and occlusion and therefore cerebral infarcts e.g. infective vasculitis

Question 339

What is nevoid basal cell carcinoma syndrome

Answer 339

Autosomal dominant disorder which can result in the early formation of multiple odontogenic keratocysts, palmoplantar pitting, intracranial calcification, and rib anomalies Can lead to multiple basal cell skin carcinomas

Question 340

Why might ICU patients end up with incontinence after their stay

Answer 340

After using a catheter, the pelvic muscles can become weak, and patients may struggle to control their bladder Continence should return to normal with time.

Question 341

Most basal cell carcinomas have mutations affecting which signalling pathway

Answer 341

Hedgehog signaling - mutations cause uncontrolled signalling This pathway controls polarity and CNS development during embryogenesis and regulates follicle formation and hair growth

Question 342

What is the most common mechanism of death in ARDS and what is its mortality

Answer 342

Most common mechanism of death is from sepsis, multi-organ failure or severe lung injury. A 2016 study found mortality to be between 35-46%

Question 343

What is diffuse axonal injury

Answer 343

Shearing/tearing of brain axons at microscopic level Caused by mechanical forces - mainly rotational acceleration which causes unrestricted head movement. One of the most common and important pathologic features of traumatic brain injury (TBI)

Question 344

How does hypertension lead to haemorrhagic CVA

Answer 344

Hx causes accelerated atheroscelrosis in larger arteries, hyaline arterioscelrosis in smaller arteries and if sever can cause proliferative changes or frank necrosis in arterioles The arteriolar walls that have been altered by hyaline changes are thickened but are more vulnerable to rupture = haemorrhage

Question 345

Describe the morphological appearance of intracerebral haemorrhage

Answer 345

Characterised by a central core of clotted blood that compresses the adjacent parenchyma The compression causes secondary infarction Anoxic neuronal and glial changes + oedema Oedema eventually resolve, haemosiderin- and lipid-laden macrophages appear + proliferation of reactive astrocytes is seen (periphery of lesion). Cellular events then resemble those that occur after cerebral infarction

Question 346

Describe the clinical effects of intracerebral haemorrhage

Answer 346

These bleeds can be clinically devastating if a large part of brain is involved or there is extension into ventricular system Can be clinically silent if affecting smaller regions or evolves like an infarct

Question 347

List the 3 meningeal layers

Answer 347

Dura mater Arachnoid mater Pia mater

Question 348

How do you manage a haemorrhagic CVA

Answer 348

Any patient that is anticoagulated will get transfusion of blood products to reverse the effects of the anticoagulation Osmotic diuretics (Mannitol) - to reduce the ICP Antihypertensive medication If the bleed is large then a craniotomy can be performed AVM and aneurysms can occasionally be repaired surgically Bleeding aneurysms can be managed with clipping or endovascular embolisation

Question 349

How common are long-term cognition issues after ICU stay

Answer 349

40-80% of ICU patients will develop some form of cognitive issue such as forgetfulness or not being able to think clearly

Question 350

Describe the clinical outcomes of severe global cerebral ischemia

Answer 350

Patients will have widespread neuronal death irrespective of the regional vulnerabilities If the patient does survive this event they will likely remain in a persistent vegetative state or may meet the criteria for brain death. If the individual remains ventilated in a persistent vegetative state they will end up with respirator brain due to the brain gradually undergoing widespread liquefaction

Question 351

What is the most common cause of an infective vasculitis leading to focal ischemic CVA

Answer 351

Opportunistic infection like aspergillosis in someone immunosuppressed by syphilis TB can also cause an infective vasculitis leading to a focal Ischemic CVA

Question 352

How do obstetric events cause DIC

Answer 352

Procoagulants can enter the circulation from the amniotic fluid, placenta or dead retained foetus

Question 353

What is a a watershed area of the brain

Answer 353

These regions are the regions where to ends of an arterial supplies territory meet

Question 354

List the clinical features of haemorrhagic CVA

Answer 354

Acute onset neurological signs (stroke) -exact signs depend on the region of the brain affected It is possible for a haemorrhagic CVA to be clinically silent if a small enough region is affected Patients are also often hypertensive as Hx is the most common underlying cause of these bleeds Headache, altered mental status, seizures, marked Hx and nausea and vomiting

Question 355

What is the normal ICP in a young child

Answer 355

3-7 mmHg

Question 356

List the clinical signs seen in an lobar haemorrhagic CVA

Answer 356

Contralateral hemiparesis or sensory loss Homonymous hemianopia Contralateral conjugate Gaze paresis Abulia - absence of willpower or an inability to act decisively Apraxia - inability to perform learned (familiar) movements on command Neglect

Question 357

What is the most common type of non-melanoma skin cancer

Answer 357

Basal cell carcinoma - accounts for 80% of cases Squamous cell makes up the other 20%

Question 358

Why are tracheostomies performed on ICU patients

Answer 358

Often used if someone is in ICU for a long time as ventilation tubes can cause damage and are uncomfortable.

Question 359

What causes secondary haemorrhagic infarcts in focal ischaemic CVA

Answer 359

They occur because of reperfusion injury that follows either therapeutic or spontaneous restoration of blood flow

Question 360

How does geography affect the incidence of squamous cell skin carcinoma

Answer 360

Live close to equator tend to present SCC at a younger age | Highest incidence: Australia

Question 361

What is the other name for non-communicating hydrocephalus

Answer 361

Obstructive hydrocephalus

Question 362

What is the ideal placement for a venous line and why

Answer 362

Subclavian vein is ideal placement as lower infection rate

Question 363

Describe the proliferation phase of wound infection

Answer 363

Begins as cells that migrate to the site of injury start to proliferate - cellularity of wound increases Angiogenesis, epithelial cell & fibroblast proliferation Marginal basal cells migrate across the wound -> epithelialized Number of inflammatory cells decreases with the increase in stromal cells

Question 364

Describe the incidence of high grade sarcoma

Answer 364

Annual incidence of soft-tissue sarcomas ranges from 15 to 35 per 1 million population The incidence increases steadily with age; Slightly higher in men than in women

Question 365

How do the lungs recovery from ARDS

Answer 365

Recovery can take some time as epithelial necrosis and inflammation prevent the surviving cells from helping to resorb the oedema. If the inflammatory stimuli decreases, macrophages can start to remove the debris from the alveoli, and they release growth factors which stimulate fibroblasts and collagen deposition. This leads to fibrosis of the alveolar walls Type II cells proliferate to repair the alveolar lining - they also replace type I cells, so lining is altered. Uninjured capillary epithelial cells will also proliferate to repair the endothelium.

Question 366

List the potential GCS scores for eyes

Answer 366

4 – Eyes opening spontaneously 3 – Eyes opening to sound 2 – Eyes opening to pain 1 – No response

Question 367

How does DIC eventually increase bleeding risk

Answer 367

This widespread formation of clots causes consumption of the clotting factors and platelets which will eventually lead to an increases bleeding risk This also occurs due to a release of plasminogen which cleaves fibrin and digests clotting factors V and VIII, reducing their availability further The fibrin degradation products also inhibit platelet aggregation, fibrin polymerisation and thrombin = decreased clotting

Question 368

List possible symptoms seen in a posterior cerebral artery stroke

Answer 368

``` Contralateral homonymous hemianopsia Cortical blindness Visual agnosia Altered mental status Impaired memory ```

Question 369

What causes ICP

Answer 369

An increase in volume of any one of the intracranial components - brain, CSF, blood

Question 370

The majority of extradural haematomas follow a skull fracture - true or false

Answer 370

True | 85%

Question 371

How does pulmonary oedema occur in ARDS

Answer 371

Endothelial activation and injury makes the capillaries leaky which leads to interstitial and alveolar oedema

Question 372

The type II alveolar cells become damaged in ARDS - true or false

Answer 372

True | This reduces surfactant and impacts gas exchange

Question 373

How do lacunar infarcts present

Answer 373

The presentation will depend on their location. | They can be clinically silent or they can cause severe neurological impairment

Question 374

Which blood products may be used in DIC and why

Answer 374

Blood products such as FFP, platelets and cryoprecipitate can be used to replace the missing components

Question 375

What is wound colonisation

Answer 375

Colonisation refers to the presence of microbial organisms within the wound that undergo limited proliferation without evoking a host reaction

Question 376

List the microscopic features of high grade sarcomas

Answer 376

``` Spindle cell pattern Large pleomorphic neoplastic cells Hyperchromatic Abnormal mitotic figure Positive for vimentin by immunohistochemical staining ```

Question 377

What can cause obstruction to CSF flow

Answer 377

Masses | Chiari Syndrome

Question 378

Which genes are associated with lobar intracerebral haemorrhage

Answer 378

Apolipoprotein E (ApoE) – e2 or e4 allele increases risk of bleeding AD forms are assoc. with with APP gene mutations

Question 379

What is the purpose of the dural septae

Answer 379

They restrict displacement of the brain, like a seatbelt

Question 380

Describe the role of pressure autoregulation in the autoregulation of cerebral blood flow

Answer 380

Arterioles dilate or constrict in response to changes in BP or ICP

Question 381

List some of the complications of treatment for high grade sarcoma

Answer 381

Surgery - infection or wound dehiscence Infection (from immunosuppression) Postirradiation sarcoma ( usually >10 years after radiation therapy)

Question 382

How does a subarachnoid haemorrhage present

Answer 382

Thunderclap’ headache, often rapid neurologic deterioration | Secondary injury may emerge and is associated with vasospasm

Question 383

Describe the appearance of the infarct caused by ischaemia of the border between the anterior and middle cerebral arteries

Answer 383

Tends to form a cortical wedge shaped infarct a few cm from the interhemispheric fissure Infarct usually shows secondary haemorrhagic transformation Commonly bilateral.

Question 384

List the most common clinical signs of a focal ischaemic CVA

Answer 384

The main clinical symptoms are focal neurological deficits that depend on the site of the brain that is effected May have hemiparesis, monoparesis, quadriparesis, hemisensory deficits, monocular/binocular visual loss, visual field deficits, diplopia, dysarthria, facial droop, ataxia, vertigo, aphasia, sudden drop in conscious level These signs can be independent but patients tent to have multiple of them

Question 385

DIC has a huge range of clinical presentations which vary with cause - true or false

Answer 385

True

Question 386

Discuss the mortality rate for high-grade sarcoma

Answer 386

High-grade soft tissue sarcomas over 10 cm in diameter have an approximate 50% mortality rate Those over 15 cm in diameter have an approximate 75% mortality rate

Question 387

Give an overview of the pathogenesis of ARDS

Answer 387

``` Pneumocyte damage Endothelial activation Neutrophil adhesion and degranulation Capillary leakage leading to oedema Recovery via resolution of inflammation, fibrosis and proliferation of surviving cells ```

Question 388

What is the typical mechanism of death in focal ischaemic CVA

Answer 388

If enough brain tissue is destroyed then these events can be fatal themselves The oedema that they cause could also raise the ICP leading to brainstem herniation

Question 389

What is the most common causative organism for infections in ICU

Answer 389

Bacteria

Question 390

What causes pressure ulcers

Answer 390

Caused by prolonged immobilisation - as seen in ICU. | The pressure causes the skin to be deprived of blood flow, which can result in skin breakdown.

Question 391

Cerebral blood flow can remain constant over which BP range

Answer 391

50-150 mmHg Below or over this blood flow becomes disrupted Below = artery collapse, impaired dilatation and ischaemia Above - force causes dilatation, you get increased flow and oedema

Question 392

List some of the complications associated with feeding tubes

Answer 392

Risks associated with misplacement

Question 393

What is hydrocephalus

Answer 393

It is the buildup of fluid in the cavities (ventricles) deep within the brain

Question 394

How does diffuse axonal injury present

Answer 394

Reduced consciousness and coma | Can lead to vegetative state

Question 395

List the consequences of H2 receptor antagonist treatment

Answer 395

H2 antagonists have the potential for the development of tolerance, and can have adverse effects (e.g., confusion or agitation)

Question 396

Cerebral amyloid angiopathy commonly causes which pattern of haemorrhage

Answer 396

Lobar pattern of intra-cerebral/intra-parenchymal haemorrhage involving the subcortical white mater, often with extension into the SAS

Question 397

How do you diagnose ARDS

Answer 397

``` Requires 4 features to be present: Acute onset Bilateral infiltrates on CXR Pulmonary capillary wedge pressure <19mmHg or a lack of clinical congestive heart failure (measured via pulmonary artery catheter Refractory hypoxaemia ```

Question 398

What is another name for reactive gastritis

Answer 398

Stress-Related Mucosal Disease

Question 399

Why is the incidence of squamous cell skin carcinoma rising

Answer 399

Due to aging population, improved detection, increased use of tanning beds, environmental factors e.g. depletion of the ozone layer

Question 400

Which factors increase the risk of developing reactive gastritis

Answer 400

Increasing number of days of mechanical ventilation | Increasing length of ICU stay.

Question 401

What is the most common location for an extradural haematoma

Answer 401

Temporoparietal region Usually due to disruption of middle meningeal artery (anterior branch is vulnerable since it runs under pterion) Less commonly in the frontal, occipital or posterior fossa regions

Question 402

What can cause decreased absorption of CSF

Answer 402

SAH Meningitis Malignant meningeal disease

Question 403

How can you prevent additional ischaemic injury from vasospasm in SAH

Answer 403

High-fluid intake (.>3500ml/day) and CCBs to prevent vasospasm CCBs dilate the vessels

Question 404

What causes a focal ischaemic CVA

Answer 404

These occur because a localised area of the brain has a reduction or cessation of blood flow due to either partial or complete arterial obstruction

Question 405

Why is HAP often life-threatening in the ICU

Answer 405

It is superimposed on the already severe illness.

Question 406

What effect can thrombotic occlusion of the cerebral arteries have

Answer 406

The thrombi may cause antegrade extension or fragmentation and distal embolisation Cause focal CVA

Question 407

List the potential outcomes for someone with ARDS

Answer 407

Those that survive will often recover their pulmonary function, but some are left with interstitial fibrosis and chronic pulmonary disease

Question 408

Can wound infection be fatal

Answer 408

Yes | 77% of deaths of surgical patients were related to surgical wound infection

Question 409

List the microscopic features of basal cell carcinoma

Answer 409

Tumor cells resemble those in the normal basal cell layer of epidermis Arise from epidermis or follicular epithelium Appear as either a multifocal superficial or nodular pattern Palisading Basaloid cells within dermis In sections, stroma retracts away from the carcinoma -> create clefts or separation artifacts that assist in differentiating basal cell carcinomas

Question 410

What is the most common site for cellulitis

Answer 410

The leg

Question 411

What determines the prognosis of a haemorrhagic CVA

Answer 411

The severity of the CVA and the location and size of the bleed Very large bleeds or bleeds that extend into the ventricular system can be devastating

Question 412

Why do the lungs become stiff in ARDS

Answer 412

Type II alveolar cells are damaged which leads to a lack of surfactant

Question 413

Where are thrombi commonly found in DIC

Answer 413

In the brain, heart, lungs, kidneys, adrenals and liver.

Question 414

List possible symptoms seen in a middle cerebral artery stroke

Answer 414

Contralateral hemiparesis and hypaesthesia Ipsilateral hemianopsia Gaze preference towards side of lesion Agnosia Receptive or expressive aphasia -if lesion in dominant hemisphere Neglect and inattention

Question 415

What temporary sensation changes may be experienced by ICU patient's

Answer 415

Certain medications can alter hearing or leave a strange taste. IV feeding can alter taste when patients start eating again - may taste stronger or different Eyes can be dry and sore from long periods of sedation, or they can be swollen and puffy due to fluid administration.

Question 416

How do you manage a subarachnoid haemorrhage

Answer 416

Urgent non-contrast CT for head trauma If normal do LP = may show xanthochromia CT angio – identify location of abnormality & provide route for endovascular coiling. Craniotomy + microsurgical clipping of aneurysm Secure the aneurysm <48hrs for reduced rupture risk and lower disability rates.

Question 417

List the clinical signs seen if a haemorrhagic CVA occurs in the brainstem

Answer 417

``` Facial weakness Quadriparesis Gaze paresis Occular bobbing Decreased conscious level Autonomic instability ```

Question 418

Which type of anaemia is seen in DIC

Answer 418

Microangiopathic anaemia | Caused by red cells fragmenting as they try to squeeze through the occluded vessels

Question 419

Which types of basal cell carcinoma will get topical therapy

Answer 419

Nonrecurring and superficial | Typically low-risk patients with superficial BCC who cannot undergo surgery or radiation

Question 420

DIC is an acquired conditions - true or false

Answer 420

True It occurs as a result of another illness/event Does not occur on its own

Question 421

What is xeroderma pigmentosum

Answer 421

An autosomal recessive disease which results in the inability to repair UV-induced DNA damage Can lead to squamous and basal cell skin cancer

Question 422

How can causes of increased ICP be classified

Answer 422

``` By their mechanism Can be: Mass Brain swelling An increase in central venous pressure ```

Question 423

Where does melanoma typically metastasise to

Answer 423

May occur locally - within or around the primary site In the regional lymph node basins ``` Or distally: Remote skin (away from the melanoma scar) Remote lymph node(s) Viscera Skeletal CNS sites ```

Question 424

Which sharp force injuries are often seen in RTAs

Answer 424

Incisions – May see (‘dicing’ or otherwise) due to shattered glass/ ejection through window/ windscreen Stab wounds/ puncture wounds – May be the result of impact w/ loose objects e.g. pens (much rarer)

Question 425

What forms the hyaline membranes seen in ARDS

Answer 425

The protein rich oedema fluid and dead type II cells become organised into the hyaline membranes

Question 426

What is the most common cause of thrombotic occlusion of the cerebral arteries

Answer 426

Acute changes in atherosclerotic plaques The carotid bifurcation, origin of the middle cerebral artery and both ends of the basilar artery are the most common sites effected

Question 427

List risk factors for squamous cell skin cancer

Answer 427

UV exposure - fair skin and albinism make you vulnerable Immunosuppression -Iatrogenic and noniatrogenic e.g. in organ transplant recipients or HIV patients respectively carcinogens HPV infection Hydrochlorothiazide use Dermatoses e.g. Xeroderma pigmentosum, Dystrophic epidermolysis bullosa, Epidermodysplasia verruciformis, Erosive lichen planus

Question 428

Describe the morphological appearance of old intracerebral haemorrhages

Answer 428

Areas of parenchymal cavitary destruction with a rim of brownish discolouration.

Question 429

List the potential limitations of GCS scoring

Answer 429

Assessment impaired by intoxication Poor reproducibility between clinicians, especially motor responses Often reported as a total score rather than constituent parts – same score may predict vastly different outcomes depending on point distribution May miss unilateral pathology

Question 430

What are the 3 components within the skull

Answer 430

Brain -80% Blood - 10% Cerebrospinal fluid -10% 100-150ml of each

Question 431

Describe the mortality of focal ischaemic CVA

Answer 431

The Framingham and Rochester stroke studies suggested that the 30 day mortality was 19% and that the 1yr survival rate was 77% The prognosis will however depend upon the individual patients, their premorbid condition and age, post stroke complication and the severity of the event

Question 432

Describe the natural progression of basal cell skin carcinoma

Answer 432

They enlarge slowly Rarely metastasise Do need treated as they can be locally destructive They can become large, cause disfigurement, spread to other parts of body and cause death

Question 433

What is intracerebral haemorrhage

Answer 433

Rupture of small intraparenchymal vessel leading to primary haemorrhage within brain

Question 434

Describe the natural history of SAH

Answer 434

25-50% die with the first rupture Those that survive often improve and recover consciousness in mins Repeat bleeding is common and unpredictable; prognosis worsens with each bleed

Question 435

What is the most common cause of wound infection following vascular surgery

Answer 435

S aureus, Staphylococcusepidermidis, gram-negative bacilli

Question 436

What is the most common antibiotic used to treat wound infection

Answer 436

Cefazolin 1-2g Used for all except colorectal surgery wounds (they use Cefotetan or cefoxitin plus oral neomycin and oral erythromycin)

Question 437

List the mechanisms involved in the autoregulation of cerebral blood flow

Answer 437

Pressure autoregulation Metabolic autoregulation CO2 levels

Question 438

List some inhaled irritants that can cause ARDS

Answer 438

Oxygen toxicity Smoke Irritant gases or chemical

Question 439

List the 3 main phases of wound infection

Answer 439

Inflammatory phase Proliferative phase Maturation phsae

Question 440

What is the main cause of lacunar infarcts

Answer 440

Hypertension that effects the deep penetrating arteries that supply the basal ganglia, hemispheric white matter and brainstem

Question 441

List some of the serious illnesses that can result from cellulitis

Answer 441

Lymphangitis , abscess formation and gangrenous cellulitis or necrotizing fasciitis Spreads along deep fascia – high mortality if spread to trunk (cannot move) -> cyanotic or septic shock GABHS and S. aureus produce toxins that may mediate a more severe systemic infection -> septic shock -> death

Question 442

Which cancers are associated with intra-parenchymal brain haemorrhage

Answer 442

High-grade gliomas or certain metastases - melanoma, choriocarcinoma, RCC

Question 443

What causes Kaposi sarcoma

Answer 443

Seen in patients with HIV/AIDS | Caused by infection with the human herpesvirus type 8

Question 444

List early signs and symptoms of a raised ICP

Answer 444

``` Decreased level of consciousness Headache Pupillary dysfunction +/- papilloedema Changes in vision Nausea and vomiting ```

Question 445

List non-medical/surgical management options for raised ICP

Answer 445

Maintain head in midline to facilitate blood flow Loosen tube ties, collars etc. Put head of the bed at 30-45 degrees elevation Avoid gagging, coughing etc. Decrease environmental stimuli Treat hyperthermia Maintain fluid balance and normal electrolytes Maintain normocarbia

Question 446

Describe the role of inflammatory mediators in diffuse axonal injury

Answer 446

Pro- and anti-inflammatory mediators; cytokines and interleukins appear to have a role IL-6 levels are higher in non-survivors

Question 447

Which patients are most at risk of haemorrhagic CVA due to CAA

Answer 447

CAA is most common in the elderly so they are at most risk Polymorphisms in ApoE resulting in the presence of E2 or E4 increase the risk of haemorrhagic CVA in patients with CAA

Question 448

List some hematological conditions that can cause ARDS

Answer 448

Transfusion-associated lung injury | DIC

Question 449

All infarcts in focal ischaemic CVA will start out as non haemorrhagic infarcts/ischemic infarcts - true or false

Answer 449

True | This is because the brain has an end arterial supply and a lack of collaterals

Question 450

List the potential GCS scores for movement response

Answer 450

``` 6 – Obeys commands 5 – Localises to pain 4 – Normal flexion/ withdrawal from pain 3 – Abnormal flexion to pain 2 – Abnormal extension to pain 1 – No response ```

Question 451

List the clinical signs seen if a haemorrhagic CVA occurs in the putamen

Answer 451

Contralateral sensory loss and hemiparesis Contralateral conjugate gaze paresis Aphasia Neglect Apraxia - inability to perform learned (familiar) movements on command Homonymous hemianopia

Question 452

List potential causes of focal ischemic CVA

Answer 452

Embolism Fat or bone marrow emboli Thrombotic occlusion of the cerebral arteries Inflammatory conditions

Question 453

List risk factors for melanoma

Answer 453

Exposure to sunlight, particularly UV-B radiation Light-colored skin Presence of freckling and benign nevi Genetics – familial atypical multiple mole and melanoma (FAMMM) syndrome

Question 454

How do you treat basal cell carcinoma

Answer 454

Removal of the tumour with the best possible cosmetic result If fat is reached -surgical excision Topical Treatment - e.g. topical 5-fluorouracil 5% Radiation Photodynamic therapy Systemic Retinoids Hedgehog Pathway Inhibitors e.g. Vismodegib, Sonidegib Checkpoint Inhibitor

Question 455

Why might ICU patients end up with voice changes after their stay

Answer 455

Being on a ventilator can cause someone's voice to change due to a sore throat and extremely dry mouth

Question 456

Is reactive gastritis reversible

Answer 456

Yes If the underlying cause is treated the mucosa will heal via complete re-epithelialisation within days to weeks. In a healthy patient the lesions do not recur.

Question 457

Which areas of the brain are typically affected by lacunar infarcts

Answer 457

In descending order of frequency ; | Putamen, globus pallidus, thalmus, internal capsule, deep white matter, caudate nucleus and pons

Question 458

Describe the role of excitotoxicity in diffuse axonal injury

Answer 458

Excitatory amino acids (glutamate) activate NMDA receptors | Ca2+ mediated activation of proteases and lipases

Question 459

List some of the long term complications of ICU

Answer 459

``` Weakness and stiffness Fatigue Loss of appetite and weight loss Sleep problems Depression, anxiety and PTSD Issues with mental ability/cognition Skin and hair changes Temporary sensation changes Breathing issues Voice changes Incontinence ```

Question 460

Why do people in ICU experience weight loss

Answer 460

Associated with a loss of appetite | The weight loss can be due to muscle loss

Question 461

List potential causes of pulmonary oedema due to alveolar wall injury

Answer 461

``` Infections - e.g. bacterial pneumonia Lung trauma Liquid aspiration - gastric content or near drowning Inhales gases - high O2, smoke Radiation Systemic inflammatory response syndrome - sepsis, burns etc. Blood-transfusion related Drugs and chemicals - chemo agents etc. ```

Question 462

What is the most common cause of haemorrhagic CVA

Answer 462

Hypertension | It is responsible for >50% of clinically significant haemorrhages

Question 463

Which organisms are the most common of cellulitis in the elderly/diabetics (general cases)

Answer 463

GAS | S aureus

Question 464

What is more common malignant or benign soft tissue tumours

Answer 464

Benign soft-tissue tumors occur at least 10 times more frequently than malignant ones

Question 465

How does immunosuppression lead to squamous cell skin carcinoma

Answer 465

It reduces host surveillance and increasing the susceptibility of keratinocytes to infection and transformation by viruses, particularly HPV subtype 5 and 8 E.g. chronic immunosuppression as a result of chemotherapy/organ transplantation

Question 466

Which surgical therapies are used for the treatment of high-grade sarcoma

Answer 466

Complete local excision for benign soft-tissue tumors ``` Extremity sarcoma may get larger surgery such as: Intracapsular excision and amputation Marginal excision and amputation Wide excisions and amputation Radical excision and amputation ```

Question 467

What is ARDS

Answer 467

a clinical syndrome of progressive respiratory insufficiency caused by diffuse alveolar damage in the setting of sepsis, severe trauma or diffuse pulmonary infection

Question 468

At which ICP is intervention required

Answer 468

A value above 20mmHg usually signifies the point at which intervention may be required to avoid significant or life-threatening consequences.

Question 469

How do you treat melanoma

Answer 469

Biopsy – evaluate the thickness of lesion Excisional biopsy – for small lesions or large lesions in cosmetically favorable locations Punch biopsy Excision Mohs micrographic surgery Adjuvant systemic therapy for: (1) those with stage IIB or III with high risk of recurrence (2) distant metastases

Question 470

What causes a Curling ulcer in reactive gastritis

Answer 470

These occur in the proximal duodenum following severe burns or trauma

Question 471

How can intracranial disease lead to reactive gastritis

Answer 471

The GI lesions are thought to occur as a result of direct stimulation of the vagal nuclei which triggers gastric acid hypersecretion

Question 472

Which wound characteristics can increase the risk of wound infection

Answer 472

Nonviable tissue in wound Haematoma Foreign material Pre-existent sepsis

Question 473

List some of the complications of a focal ischaemic CVA

Answer 473

1/2 of patients will be left with some from of disability/ neurological deficit - will depend in the severity and location of the infarct There is however usually some improvement in the patients condition in the first few months following the stroke

Question 474

What causes endothelial injury in DIC

Answer 474

Can occur due to inflammation, antigen-antibody complexes, extreme temperatures and microorganisms. Leukocytes damage cells by releasing ROS and proteases

Question 475

What causes global cerebral ischaemia

Answer 475

This occurs when there is a generalised reduction of cerebral perfusion (i.e. due to shock, severe hypotension or cardiac arrest) or if the blood is not able to carry as much O2 ( i.e. CO poisoning)

Question 476

What is the most common cause of wound infection following colorectal surgery

Answer 476

Gram-negative bacilli and anaerobes

Question 477

How do you diagnose DIC

Answer 477

Based on clinical observation and blood tests. ``` Blood tests include: Fibrinogen levels Platelets PT and PTT D-dimers ```

Question 478

If the occlusion that is causing a focal ischemic CVA is in a large artery what is the most likely cause

Answer 478

An emboli

Question 479

List some physical injuries that can cause ARDS

Answer 479

``` Mechanical trauma - including head injury Pulmonary contusions Near-drowning Fractures with fat embolism Burns Ionising radiation ```

Question 480

Describe the features of a class 3 - contaminated surgical wound

Answer 480

Nonpurulent inflammation present Gross spillage from gastrointestinal tract Penetrating traumatic wounds < 4 hours Major break in aseptic technique

Question 481

List the microscopic features of ARDS in the organisation phase

Answer 481

In this stage, type II pneumocytes proliferate and granulation tissue forms in the alveoli (walls and spaces) In most cases this resolves but in some fibrotic thickening occurs which is scarring.

Question 482

Any disruption of O2 supply to the brain will cause damage to the brain - true or false

Answer 482

True This is because it can no longer meet its energy requirements Can be due to reduced perfusion or hypoxemia

Question 483

Describe a spreading wound infection

Answer 483

Spreading infection describes the invasion of the surrounding tissue by infective organisms that have spread from a wound

Question 484

Which organisms are the most common of cellulitis in hospital acquired cases

Answer 484

<24 hours postoperatively: GABHS or Clostridium perfringens | Acinetobacter baumannii – emerging multidrug-resistant pathogen

Question 485

List late signs and symptoms of a raised ICP

Answer 485

``` Coma Fixed, dilated pupils Hemiplegia Cushing’s triad - bradycardia, increase BP and altered respiration pattern Hyperthermia Increased urinary output ```

Question 486

Describe the pathological features of haemorrhagic CVA

Answer 486

A central core of clotted blood that will compress the adjacent parenchyma is found within acute primary parenchymal haemorrhages . The compression that this clotted blood causes will lead to secondary infarction of the effected tissue and so anoxic neuronal injury, glial changes and oedema will be seen Over time the oedema will resolve and there will be an appearance of heamosiderin and lipid laden macrophages. Additionally there will be proliferation of reactive astrocytes at the lesions edges The cellular events follow the same time course as cerebral infarction (Focal Ischemic CVA infarctions) Once the haemorrhage is old there will be areas of parenchymal cavitary destruction that have a rim of brownish discolouration

Question 487

What is the normal ICP in an older child

Answer 487

10-15 mmHg

Question 488

Basal cell carcinoma rarely metastasise - true or false

Answer 488

True

Question 489

Why does in increase any one of the intracranial components cause an increase in pressure

Answer 489

Because the cranium is fixed - cannot accommodate change

Question 490

Describe the pathological features of lobar intracerebral haemorrhage caused by CAA

Answer 490

Amyloidogenic peptides are deposited in vessel walls - makes them rigid The deposits also weakens vessel wall and can cause haemorrhage Looks similar to hyaline arteriosclerosis on H&E stain except the material in CCA consists of beta-amyloid rather than collagen and is in a different location

Question 491

What is the most common mechanism of death from haemorrhagic CVA

Answer 491

The build up of blood in the tissue and associated cerebral oedema raising the ICP and causing herniation of the brainstem

Question 492

How can you prevent pressure ulcers

Answer 492

Routine position changes done to reduce risk

Question 493

List potential complications of endovascular embolisation of an aneurysm

Answer 493

Thromboembolic events or perforation of the aneurysm

Question 494

Which type of cellulitis is seen in children under 3

Answer 494

Buccal cellulitis caused by H influenzae type B | Perianal cellulitis with GABHS

Question 495

Which molecule is being considered as a new biomarker for traumatic brain injury

Answer 495

Plasma levels of von Willebrand factor May also be able to indicate severity VWF is a glycoprotein released in endothelium in response to local trauma - indicator of traumatic microvascular injury. It can act as a biomarker of cerebrovascular pathology Increased expression of the factor is associated with vascular and neurodegenerative dementia

Question 496

When is surgical resection and adjuvant therapy used in the treatment of high grade sarcoma

Answer 496

For recurrent and metastatic disease

Question 497

What is photodynamic therapy

Answer 497

Process of using specific wavelengths of light to photoexcite porphyrins Used in the treatment of BCC

Question 498

List the macroscopic features of ARDS

Answer 498

Lungs are heavy, firm, red and boggy in the acute phases. Lesions are not evenly distributed so some areas are stiff and poorly ventilated whilst others remain normal.

Question 499

How long can it take to recover from an ICU stay

Answer 499

These issues can persist for several months and may require ongoing treatment. E.g., physical recovery can take up to 18 months and will require slowly building up strength.

Question 500

List some of the complications associated with ventilators

Answer 500

They are the biggest risk factor for hospital-acquired lung infection. Thought to be because its easier for bacteria to get in as bypassing the defenses of nose and mouth Can cause barotrauma (injury to body due to changes in barometric (air) or water pressure) or even GI bleeds. Some patients may experience weaning errors

Question 501

List common sources of emboli that occlude the cerebral vessels

Answer 501

Cardiac mural thrombi are most common Thromboemboli from atherosclerotic plaques, most commonly in the carotids, are the second most common Rarer sources of the emboli include; paradoxical emboli, fat, tumour and air emboli or thromboembolic emboli from cardiac surgery

Question 502

What are the 3 most common sites of hospital acquired infection

Answer 502

Lungs Blood Urine

Question 503

List the symptoms of ARDS

Answer 503

Severe dyspnoea and tachypnoea Tachycardia Progresses to: Respiratory failure Hypoxaemia - often refractory in response to O2 Cyanosis Peripheral vasodilation Bilateral fine inspiratory crackles Respiratory acidosis - lungs not functioning Lungs become stiff due to a lack of surfactant

Question 504

List the microscopic features of reactive gastritis

Answer 504

Acute stress ulcers are well demarcated, and the adjacent mucosa is typically normal. Serositis may be present.