Interview questions Flashcards
1
Q
What is an EVD?
A
External Ventricular Drain
a soft catheter/ flexible tube that is inserted into the anterior horn of the lateral ventricle
for drainage of CSF and to monitor intracranial pressure
the catheter is connected to a drainage system outside of the body and drains via gravity. It can be opened or clamped to control the rate of drainage
2
Q
What are the reasons for using an EVD?
A
- to reduce intracranial pressure caused by build up of CSF (possible due to a blockage)
- to divert infected CSF away from the brain & to give antibiotics directly into the CSF to treat the infection
- to drain excess fluid/blood post surgery or after a brain bleed
3
Q
What symptoms would you expect if not enough CSF is being drained through the EVD?
A
- bulging of fontanelle in infants
- headaches
- vomiting
- irritability
- lethargy
4
Q
What symptoms would you expect if too much CSF is being drained through the EVD?
A
- sinking of fontanelle in infants
- headaches
- pallor
- tachycardia
- irritability
5
Q
What are possible EVD complications?
A
- Ventriculitis
- suspect if CSF glucose <50mg/dl
- higher risk if catheter has been in for a long time
- treat with Vancomycin & an anti-pseudomonal beta-lactam - Catheter occlusion
- intracranial hypotension
- blood being drained is coagulated and too thick
- ventricular wall has collapsed around the catheter - Over-drainage
- can result in subdural haemorrhage or upwards herniation
6
Q
What is a subarachnoid haemorrhage?
A
bleeding into the subarachnoid space (between arachnoid and pia mater)
it is a life threatening condition which causes brain damage through hypoxia, raised ICP and direct cranial injury
7
Q
Causes of subarachnoid haemorrhages?
A
Traumatic injuries such as road traffic accidents
Or spontaneous, due to:
- intracranial aneurysms
- arteriovenous malformation
- unknown
8
Q
What are risk factors for spontaneous subarachnoid haemorrhages
A
- hypertension
- smoking
- family history
- age >50
- female sex
9
Q
What are the 3 typical symptoms of subarachnoid haemorrhage?
A
- thunderclap headache - sudden onset severe headache reaching max intensity within seconds
- nausea & vomiting
- photophobia
10
Q
What are typical clinical findings of subarachnoid haemorrhage?
A
- reduced consciousness - usually secondary to raised ICP
- neck stiffness - due to meningeal irritation
- +ve Kernig’s sign - inability to extend the knee when supine and hips are flexed due to pain - this is caused by irritation of the motor nerve roots which pass through the inflamed meninges
- but this is non-specific, can also be because of meningitis
11
Q
What investigations can be carried out to confirm subarachnoid haemorrhage?
A
- plain CT head - look for blood in subarachnoid space or hydrocephalus
- CT angio - identifies aneurysms
- lumbar puncture - CSF stained yellow due to infiltration of blood from haemorrhage
12
Q
Run through an ABCDE assessment of a patient with subarachnoid haemorrhage
A
A - ensure airway is patent because patients with reduced consciousness are at risk of occluding their airways.
May require oropharyngeal airway or intubation
B - check resp rate and SpO2 - patients may be hypoxic due to occluded airway
C - check BP and pulse - IV fluids may be needed to maintain BP
Patients may require electrolyte replacement because hyponatraemia is common in SAH
Calcium channel blockers to reduced cerebral ischaemia
D - disability - if GCS <8 anaesthetist may be required to manage airway
E - investigate whether there are any primary of secondary injuries
13
Q
Management of subarachnoid haemorrhage
A
- EVD - to manage ICP and bleed
- obliteration of the ruptured aneurysm - via clipping or inserting fine wire
- ventricular drainage in cases with secondary hydrocephalus
14
Q
Complications of subarachnoid haemorrhage
A
- obstructive hydrocephalus
- arterial vasospasm - cerebral arteries vasoconstrict leading to brain ischaemia
15
Q
What is obstructive hydrocephalus?
A
occurs due to blood pooling in the ventricular system
this obstructs CSF drainage
and leads to rise in ICP
and death if untreated
diagnosed on CT as ventricles appear enlarged
EVD required
16
Q
What is hydrocephalus?
A
active distension of the ventricular system of the brain
due to inadequate passage of CSF from its point of production within the cerebral ventricles
to its point of absorption into the systemic circulation
so the increase in CSF volume distends the ventricles and sometimes increases ICP
17
Q
What are the 2 types of hydrocephalus?
A
- Communicating = ventricular distension in the presence of a patent ventricular system - due to conditions that reduce CSF absorption or increase CSF production
- like SAH - Obstructive = ventricular distension due to a blockage within the cerebral ventricular system
18
Q
Why is it important to differentiate between communicating vs obstructive hydrocephalus before doing a lumbar puncture
A
Differentiating communicating and obstructive hydrocephalus is clinically useful because a lumbar puncture can be safely performed if the patient has communicating hydrocephalus.
In contrast, a lumbar puncture risks cerebral herniation if there is high intracranial pressure in a patient with obstructive hydrocephalus.
19
Q
What is a VP shunt?
A
A ventriculoperitoneal shunt
= a medical device that connects the ventricular system of the brain with the peritoneal cavity
so CSF can drain from the ventricles into the abdomen
it runs in the subcutaneous tissue
most common indication for this is hydrocephalus
20
Q
What is an extradural haematoma?
A
acute haemorrhage between the dura mater and inner surface of the skull
can compress local brain structures and raise ICP
if not treated can cause cerebellar herniation leading to brainstem death
most common in males between 20-30
21
Q
Causes of extradural haematoma?
A
- commonly caused by skull trauma/ fracture - after fall, assault, sports injury
- rupture of middle meningeal artery
- arteriovenous abnormalities or bleeding disorders
22
Q
How does extradural haematoma appear on CT and MRI imaging?
A
as a lemon shaped haematoma
23
Q
What is the classical clinical presentation of an extradural haematoma?
A
A lucid interval following head trauma
followed by progressively decreasing level of consciousness
24
Q
What is the Cushing’s reflex?
A
a physiological response to raise ICP in order to improve perfusion
presents with classic triad of:
- hypertension
- bradycardia
- irregular breathing pattern
25
How would you initially manage extradural haematoma?
1. if patient is on anticoagulation, give them reversal agents to prevent further bleeding
2. prophylactic antibiotics to reduce risk of intracranial infection
3. anticonvulsant medical - due to increased risk of seizures - e.g. phenytoin
4. IV Mannitol to decrease ICP
or Barbiturates
26
What is the definitive management of extradural haematoma?
Craniotomy - to evacuate the haematoma and treat the cause of bleeding (e.g. ligation of blood vessel) and to reduce ICP
27
What is idiopathic intracranial hypertension?
raised intracranial pressure in the absence of intracranial mass or hydrocephalus (an abnormal increase in CSF volume)
28
What is the ACVPU or AVPU score?
rapid method of assessing a patients level of consciousness
A = Alert (fully awake)
C = Confusion (awake but with new onset or worsening confusion)
V = Voice (patient demonstrates some form of response when you talk to them (e.g. words, grunting, moving a limb))
P = Pain (patient responds to a painful stimulus (e.g. supraorbital pressure))
U = Unresponsive (no response to any stimulus)
In patients who are not fully awake, calculate GCS score for more accurate assessment
29
What is NEWS score?
a tool used to assess a patients clinical status and identify early signs of deterioration based on 6 parameters
1. Respiratory rate
2. Oxygen saturation
3. Systolic BP
4. Pulse rate
5. Level of consciousness
6. Temperature
additional 2 points if patient is on 02 therapy
5+ = urgent
7+ = severe
30
What is the Glasgow Coma Scale?
used to evaluate level of consciousness in a patient
typically used in context of head trauma
Based on 3 aspects:
1.Eye-opening (4 points if they can open)
2. Verbal response (5 points if pt is orientated)
3. Motor response (6 points if pt obeys commands)
GCS 15 = fully conscious
GCS 3 = coma or dead
escalate if it drops to 8 or below
31
What is a tracheostomy tube?
a curved tube that is inserted into an opening made in the neck and trachea to aid breathing
Reasons you may need to have a tracheostomy include:
to help you breathe if your throat is blocked
to remove excess fluid and mucus from your lungs
to deliver oxygen from a machine called a ventilator to your lungs
32
What would you do if a patient has a blocked tracheostomy tube?
This is an emergency so escalate ASAP
1. Check for signs of blockage: Look for signs like noisy breathing, laboured breathing, or blood in the tube.
Apply high flow oxygen to the face and tracheostomy
2. Suction the tube: If possible, insert a suction catheter through the tube to remove any secretions. If the catheter doesn't pass easily, the tube is likely blocked.
3. If blocked then change the inner cannula
4. Ventilate the patient: If you can't quickly proceed, you can remove the tracheostomy tube and use a manual resuscitator to ventilate the patient through their mouth and nose.
5. Deflate the cuff: If the tube remains blocked, you can deflate the cuff so the patient can breathe around the tube.
6. If this is not working then remove the tracheostomy tube and ensure oxygen is being given
Attempt oral intubation
33
What could cause a blocked tracheostomy tube?
- dried secretions
- blood clots
- a displaced over-inflated cuff
- the tracheal wall (if the tracheostomy tube is malpositioned)
34
A day 2 post op total knee replacement patient is complaining of chest pain and you are asked to assess.
What would you do? What are differentials and management?
Standard ABCDE approach
- in E mention checking calves for DVT
ESCALATE!
- take bloods including FBC, U&Es and troponin
- ECG
-if safe to do so CXR, otherwise CTPA
Differentials:
- PE
- ACS
- post-op pneumonia
Why not D-Dimer levels?
- because D-Dimer, CRP and WCC will all be raised post-op so won't help
Anticoagulation?
- tricky because will be helpful if it is PE
- but not if there is post-op haemorrhage
- safer to give because bleeds can be resusciated
35
A 23M midshaft tib/fib fracture is complaining that their pain is increasing. What would you do?
Given the injury and increasing pain, very likely to be compartment syndrome
= painful condition that occurs when pressure within the muscles builds to dangerous levels. This decreases blood flow, which prevents oxygen from reaching nerve and muscle cells, causing cell damage.
Escalate immediately
Assess for compartment syndrome
- pain worse on passive stretching
- wooden firm compartments
- pallor
- pulselessness
- paraesthesia
- paralysis
- cold
Actions:
- split cast to skin
- elevate limb
- IV morphine
- reassess in 15 mins - if no improvement then emergency theatre
36
What is malignant spinal cord compression?
medical emergency caused by compression of the spinal cord or cauda equina
due to metastatic spread of tumours
the compression is caused by direct pressure, vertebral collapse or instability
and this leads to oedema, venous congestion and demyelination
which leads to loss of neurological function, depending on the level of the lesion
37
What are the most common cancer types that can metastasise to the spine?
- prostate
- lung
- breast
- renal
- multiple myeloma
38
What are red flag features of back pain that may suggest MSCC, particularly in a patient with cancer
- thoracic or cervical pain
- progressive lumbar pain
- spinal pain that is aggravated by straining
- localised spine tenderness
- nocturnal pain because pain is worse at night and when lying flat
- limb weakness - feel heavy and stiff
- gait disturbances and unsteadiness
- autonomic dysfunction of bowel and bladder
39
What examinations would you carry out in patients with suspected MSCC?
1. full neurological examination with PR
2. urgent MRI of spine (CT if MRI is contraindicated)
3. bladder scan to assess urinary retention
4. bloods - group & save for surgery
5. tumour markers
40
What is the initial management for suspected MSCC?
1. Dexamethasone 16mg OD or 8mg BD to reduce inflammation and oedema
2. PPI - Omeprazole - for stomach protection
3. LMWH for thromboprophylaxis
4. Analgesia
41
What is the definitive management for a patient with confirmed MSCC?
This depends on the patients status
- extent of their malignancy
- other co-morbidities
- level of compression & neurological deficit
- duration of symptoms (if >48hrs, treatment is unlikely to help)
1. surgical decompression
- in patients with life expectancy >6months
- limited level of compression & neurological deficit
- followed with radiotherapy
2. radiotherapy alone
- for pts with multiple co-morbidities or rapidly progressive neurological deficit
3. supportive/palliative care
- frail, unwell or short life expectancy pts
4. rehab is essential depending on level of neurological deficit and the treatment given
42
What is a craniotomy?
surgical removal of part of the bone from the skull to expose the brain - this is replaced after the surgery has been done
used to treat
- brain tumour
- blood clots in the brain
- brain aneurysm
- skull fraction
- relieving pressure after injury or stroke
after the procedure
- feel tired
- headaches and problems concentration
- numbness and shooting pains near the wound
- swelling and bruising around the eyes
43
Risks of craniotomy
- seizures
- haematoma
- stroke
- coma
- hydrocephalus
- difficulty walking, balancing, speech
44
Prophylaxis for post-craniotomy seizures
Prophylactic anti-epileptic drugs
Keppra (Levetiracetam)
45
Two main causes of stroke
1. ischaemic - lack of blood supply to brain
2. haemorrhagic - brain bleed
- subarachnoid
- intracerebral - similar symptoms to ischaemic stroke
46
BEFAST acronym for stroke
B - balance - loss of balance?
E - eyes - loss of vision or double vision
F - face - facial droop?
A - arms - can both arms be lifted above head
S - speech - slurred?
T - time to call an ambulance
47
Differentials for stroke?
- seizures
- bell's palsy
- delirium
- intoxication
- head injuries
- hypoglycaemia
48
What is the NIHSS (National Institutes of Health Stroke Scale)
a systematic, quantitative assessment tool for stroke-related neurological deficits.
The higher the number, the greater the deficit and the bigger the stroke.
A score between 0 – 4 is given for the severity of each of the following:
Level of consciousness
Speech
Ability to obey commands
Visual field loss
Facial palsy
Strength of arm movements and presence of drift
Strength of leg movements and presence of drift
etc
49
Main investigations for stroke
CT head ASAP
CT angiogram
50
Management of ischaemic stroke
1. thrombolytic agent if pt presents withing 4.5hrs of symptom onset
- Alteplase
but not in pts who has haemorrhagic stroke, or on anticoagulants
2. mechanical thrombectomy - endovascular removal of a clot
3. if thrombectomy not recommended - aspirin 300mg for 2 weeks followed by clopidogrel 75mg lifelong
51
Management of intracranial haemorrhage
1. anticoagulant reversal (refer to haem)
2. BP lowering
Labetalol 10mg IV
52
What is a TIA
Transient Ischaemic Attack
or mini stroke
brief interruption in blood flow to the brain that causes stroke-like symptoms
- numbness/weakness in face or one side of body
- trouble seeing in one or both eyes
- difficulty walking, dizziness
sudden onset of symptoms lasting a few minutes up to a few hours
RF:
- high BP
- type 2 diabetes
- smoking
- Afib
Management
- aspirin
- warfarin
53
Indications for intubation and ventilation
pO2 < 13kPa on supplemental oxygen
pCO2 > 6kPa
Spontaneous hyperventilation causing pCO2 < 3.5kPa
54
what would pupils look like in a pt with raise ICP or cerebral herniation
blown pupils
= oval shaped
sluggish reaction to light
55
how is hypoglycaemia managed
administration of glucose, oral or IV
saline + 5% dextrose
56
Risk factors for DVT or PE
- recent surgery, fractures, immobility
- family history
- obesity
- malignancy
- infection
- pregnancy
- oral contraceptive
57
Clinical signs of PE
- Shortness of breath
- pleuritic chest pain
- cough
- dizziness
- tachycardia and tachypnoea
- hypotension
- pleural rub
- cyanosis
- red, swollen calf
- low PaO2
58
Definitive diagnosis of PE is made with what investigation
CT pulmonary angiogram
or if contraindicated then V/Q scan (renal impairment, pregnancy)
59
What is Well's score
Calculates risk of developing DVT based on
- classical signs and symptoms
- tachycardia
- immobilisation
- previous history
>4 points = PE likely
If < 4 then do a D-dimer test
60
Management of PE
1. wait for CTPA scan before starting anticoagulants, but if it will take time then start and stop later if no PE
- Apixiban
If confirmed, continue for 3 months
2. heparin infusion and thrombolytic therapy
alteplase
61
Signs of massive PE secondary to right ventricular strain
Hypotension
Raised jugular venous pressure
Heart failure
Cardiac arrest
62
what does ECG look like in PE
sinus tachycardia
t wave inversion
63
what is a pneumothorax
collection of air between the pleura of the lungs
can be:
- primary = no underlying disease
- secondary = underlying lung disease like asthma or COPD
or can be:
- spontaneous
- traumatic
64
what is tension pneumothorax
all types of pneumothorax can develop into tension pneumothorax
medical emergency due to sudden rise in intrathoracic pressure
this reduces venous return to heart and can leadto cardiac arrest
65
typical pneumothorax symptoms
- sudden onset chest pain
- acute SOB
- feeling like you cant take a full breath
- tracheal deviation away from the affected lung
- tachypnoea/tachycardia
- hypoxia
- reduced air entry and chest expansion on one side
66
CXR findings for pneumothorax
- lung collapse
- air in pleural space
- decreased lung markings
for tension pneumo
- youd see tracheal deviation
67
managment of pneumothorax
- high flow oxygen
- needle aspiration
- chest drain
68
managment of tension pneumothorax
immediate needle decompression in 2nd intercostal space
69
What is ACS
It is the result of a thrombus from an atherosclerotic plaque blocking a coronary artery
LIFE THREATENING
It includes
- STEMI
- NSTEMI
- unstable angina
70
Two types of MI
type 1 = caused by plaque rupture
type 2 = decreased supply (hypoxaemia, hypotension) or increased demand (AFib)
71
typical symptoms assosciated with ACS
- chest pain - radiating to arm neck jaw
- SOB
- palpitations
- nausea and vomiting
- sweating
- tachycardia/tachpnoea
72
typical ACS findings on ECG
STEMI: ST elevation and/or new left bundle branch block (LBBB)
NSTEMI: T wave inversion and/or ST depression
Unstable angina: often there are no specific ECG abnormalities
73
medical managemnt for acs
morphine
GTN spray (unless pt is hypotensive)
aspirin 300mg + clopidogrel
diuretics (furosemide) if signs of pulmonary oedema
IV fluids
74
management of STEMI
urgent PCI
75
what is DKA
medical emergency and complication of diabetes
when your blood turns acidic because there are too many ketones in your blood due to a lack of insulin
DKA can be caused by either:
Absolute insulin deficiency (e.g. type 1 diabetes)
Complete insulin insensitivity (e.g. insulin-dependent type 2 diabetes)
76
DKA is characterised by
Hyperglycaemia: blood glucose > 11.0mmol/L or known diabetes mellitus
Ketonaemia: ketones > 3.0mmol/L or significant ketonuria (more than 2+ on standard urine sticks)
Acidosis: bicarbonate (HCO3-) < 15.0mmol/L and/or venous pH < 7.3
77
management of DKA
1. fixed rate IV insulin infusion
2. glucose infusion - normal saline and 5% dextrose
3. potassium infusion
78
What are 3 types of post-operative bleeding
1. primary - occurs during surgery
2. reactive = within 24hrs of op
3. secondary - 7-10 days after op, usually because of wound infection
79
aymptoms of hypoglyaemia
- sweating
- palpitations
- hunger
- tremor
- confusion
- drowsiness
- speech abnormalities
80
management of hypoglycaemia
if patient is conscious
- glucose gel by mouth (GlucoGel) repeat every 10/15mins until pt is not hypoglycaemia
- when pt is fully awake give long-lasting carb to eat like toast
If pt is unconscious
- IV glucose 150ml 10% glucose
- when pt become conscious switch to oral
81
what is atrial fib
chaotic and uncoordinated electrical activity
multiple wabs of electrical activity bombard AV node --> irregular ventricular contraction
82
symptoms of Afib
- palpitations
- SOB
- dizziness
- chest pain
- irregularly irregulay pulse
- tachycardia
-no p waves on ecg
83
management of Afib
electrical cardioversion in emergency
or pharmacological - amiodarone
rate control with beta blockers - metaprolol
anticoagulation
IV fluids
84
Treatment for seizures
1. IV Lorazepam (repeat after 20mins if seizure contrinues)
2. phenytoin infusion
3. IV glucose
