ACC Flashcards
1
Q
What 2 criteria are required to diagnose septic shock?
A
1) MAP <65 mmHg despite fluid resus
2) Lactate >2 mmol/L
2
Q
What BEDSIDE score can be used to identify patients with suspected infection who are at greater risk for a poor outcome outside of ICU?
A
qSOFA
3
Q
What makes up the qSOFA score? (3)
A
1) RR >22
2) Systolic BP <100 mmHg
3) altered mental state
4
Q
What qSOFA score indicates someone at a heightened risk of mortality (10% risk)?
A
≥2
5
Q
What is the mean arterial pressure? (MAP?
A
The average pressure in a patient’s arteries during one cardiac cycle.
It is considered a better indicator of perfusion to vital organs than systolic BP.
6
Q
How does sepsis cause hypoperfusion of organs?
A
Cytokines released due to inflammation increase the permeability of blood vessels.
This causes oedema and reduced intravascular volume.
Oedema creates a gap between the blood and the tissues, reducing the amount of oxygen that reaches the tissues.
7
Q
What is released in sepsis that results in vasodilation?
A
Nitrous oxide
8
Q
In order to generate a palpable femoral pulse, what arterial pressure is required?
A
> 65 mmHg
9
Q
Which general anaesthetic has a side effect of pain on injection?
A
Propofol
10
Q
2 key adverse effects of propofol?
A
1) Pain on injection site
2) Marked drop in BP
11
Q
Which general anaesthetic has a side effect of laryngospasm?
A
Thiopental sodium
12
Q
Which general anaesthetic has a side effect of 1ary adrenal suppression?
A
Etomidate
13
Q
2 main side effects of etomidate?
A
1) 1ary adrenal suppression
2) Myoclonus
14
Q
How does etomidate cause adrenal suppression?
A
As reversibly inhibits 11b-hydroxylase
15
Q
What 2 things is malignant hyperthermia triggered by?
A
1) Suxamethonium
2) Volatile anaesthetics
16
Q
Definitive diagnosis of malignant hyperthermia?
A
Genetic testing afterwards
17
Q
Which general anaesthetic is post-op vomiting common in?
A
Etomidate
18
Q
Mechanism of IV dantrolene in malignant hyperthermia?
A
Ryanodine receptor antagonist –> helps to decrease intracellular calcium concentration and muscle metabolism
19
Q
What is the most common cause of malignant hyperthermia?
A
Autosomal dominant mutation in ryanodine receptor.
This results in an abnormality in calcium regulation within muscle cells –> leads to increased calcium levels in the sarcoplasmic reticulum and a consequent increase in metabolic rate.
20
Q
Which general anaesthetic may cause marked myocardial depression?
A
Thiopental sodium
21
Q
Inheritance of mutation in malignant hyperthermia?
A
Autosomal dominant
22
Q
What does a simple general anaesthetic induction ‘recipe’ for tracheal intubation in a fit and well patient usually incorporate?
A
Quick acting opiate e.g. fentanyl + propofol
23
Q
How many test breaths are delivered whilst confirming tube placement within the trachea?
A
5
24
Q
How is tube placement confirmed within the trachea? (3)
A
1) 5 waves on capnography
2) Symmetrical chest expansion
3) Misting of tube
25
What intraoperative monitoring is required?
(3)
1) Obs: HR, BP, O2 & capnography
2) Depth of anaesthesia: BIS monitor or MAC
3) Neuromuscular blockade w/ peripheral nerve stimulator
26
What does a BIS monitor analyse?
EEG (brain activity)
27
What medication is used specifically to reverse the effects of certain non-depolarising muscle relaxants (rocuronium and vecuronium)?
Sugammadex
28
What is the NMDA receptor?
A receptor of glutamate (the primary excitatory neurotransmitter).
29
How can the degree of the neuromuscular blockade be assessed?
Peripheral nerve stimulator
30
Where are the leads typically over in a peripheral nerve stimulator?
Facial or ulnar nerve
31
Mechanism of ketamine?
NMDA receptor antagonist
32
What class of medication can reverse the effects of neuromuscular blocking medications?
cholinesterase inhibitors e.g. neostigmine
33
What 2 GA agents do NOT cause marked hypotension?
Ketamine & etomidate
34
Who cyclizine be used with caution in?
HF & elderly
35
What inhaled GA has the worst environmental effect?
Desflurane
36
What is the main contraindication for thiopentone?
Porphyria
37
Which inhaled GA is used in organ donation?
Isoflurane (due to least effect on organ blood flow)
38
Which inhalational agent is sweet smelling?
Sevoflurane
39
What is 'train of four' stimulation?
Four consecutive 2 Hz stimuli to a chosen muscle group and the respective number of twitches evoked.
This provides information on the patient's recovery from neuromuscular blockade.
40
What are 3 common antiemetics given for prophylaxis given at the end of the operation?
1) Ondansetron
2) Cyclizine
3) Dexamethasone
41
How do muscle relaxants work?
Block ACh action at NMJ
42
What is the most common short acting opioid used at time of anaesthesia induction?
Fentanyl
43
Mechanism of cyclizine?
Antihistamine (H1 receptor antagonist)
44
What result of train-of-four (TOF) stimulation indicates that muscle relaxants haven’t fully worn off?
Muscle responses get weaker with additional stimulation
45
What is minimum alveolar concentration (MAC)?
Minimum concentration of inhaled anaesthetic at which 50% of people don't move in response to a noxious stimuli.
46
When can MAC be used to measure the depth of anaesthesia?
If VOLATILE agents are used
47
What is suxamethonium apnoea also known as?
Pseudocholinesterase deficiency
48
Which inhaled GA is associated with hepatotoxicity?
Halothane
49
What is the muscle relaxant of choice for RSI for intubation?
Suxamethonium
50
What drug is often used in epidural anaesthesia?
Levobupivacaine +/- fentanyl
51
What is the caudal space?
Extension of epidural space (at bottom of spine)
52
What are anaesthetics used for spinal anaesthesia mixed with?
Why?
Dextrose
To make them hyperbaric (i.e. denser than CSF)
53
Purpose of local anaesthetics used for spinal anaesthesia being hyperbaric?
1) Greater spread in the direction of gravity
2) More predictable with minimal inter-patient variability
54
Which nerve block is mostly performed to provide analgesia following rib fractures and thoracic surgery?
Intercostal
55
What type of peripheral nerve block is used for hand operations?
Axillary
56
Who is caudal anaesthesia more useful in?
Paediatric patients
57
What type of peripheral nerve block is used for elbow operations?
Supraclavicular
58
What is a complication of an intercostal block?
Pneumothorax
59
What are the 2 key risk factors for lidocaine toxicity?
1) Hypoalbuminaemia (as lidocaine is protein bound)
2) Hepatic dysfunction
60
Which local anaesthetic has the fastest onset?
Lidocaine
61
What is the safe dose for Lignocaine with and without adrenaline?
Without --> 3mg/kg
With --> 7mg/kg
62
Presentation of ipsilateral phrenic nerve palsy?
SOB
63
Where does the subarachnoid space end?
S1
64
What is the safe dose for bupivacaine?
2mg/kg
65
A patient is administered local anaesthetic at the end of an operation.
The surgeon infiltrates 20ml of 2% lidocaine.
How many mg of lidocaine dose this amount to?
1% lidocaine = 1g per 100ml
2% = 2g per 100ml
2g = 2000mg
2000 / 5 (as 100 / 20 = 5) = 400mg
66
What is wound dehiscence?
A post-operative complication in which a wound ruptures along the surgical incision site.
Superficial --> non-urgent senior review
Deep --> emergency
67
How should OD insulin be adjusted on the day before and day of surgery?
Generally reduced by 20%
68
How can suxamethonium affect K+?
Can cause hyperkalaemia
69
Adrenaline dose in anaphylaxis:
a) IM
b) IV
a) 0.5ml 1:1000
b) 0.5ml 1:10000
Repeat doses every 5 mins
70
When should you suspect pulmonary oedema following general anaesthetics?
In hypoxic patients following laryngospasm
71
respiratory sound in bronchospasm vs laryngospasm?
Bronchospasm - wheeze
Laryngospasm - stridor
72
What 2 things should be ruled out following laryngospasm?
1) Pulmonary oedema
2) Aspiration
73
What is intraoperative hypothermia defined as?
<36 degrees
74
What electrolyte abnormality can contribute to post-op ileus?
Hyperkalaemia
75
How can laryngospasm result in pulmonary oedema?
Inspiratory effort against the closed glottis leads to excessive negative pressure within the alveoli, resulting in pulmonary oedema.
76
How can perioperative hypothermia cause prolonged recovery from anaesthesia?
Reduction in body temperature can lead to prolongation of anaesthetic drugs, neuromuscular blocking agents and inhalational agents.
77
What 2 methods are used to monitor temp in anaesthetics?
1) Tympanic thermometer
2) Oesophageal probe
78
What is laryngospasm?
Partial or complete reflex adduction of vocal cords due to the involuntary contraction of the intrinsic muscle of the larynx.
This may cause a variable degree of upper airway obstruction.
Closure of the glottic opening is a primitive protective airway reflex to prevent aspiration.
79
At what volume should IV fluids be warmed prior to administration?
>500 ml
80
Define the pre-operative phase
Starting 1 hour before induction of anaesthesia
81
What are the 3 most common sites of insertion for a central line?
1) Internal jugular vein (most common)
2) Subclavian vein
3) Femoral vein
82
Which LA can cause cardiotoxicity?
Bupivacaine
83
Why is bupivacaine contraindicated in regional anaesthesia?
Due to cardiotoxicity - in case tourniquet fails
84
Mx of the following drugs before surgery:
a) ACEi e.g. ramipril
b) sulfonylureas
c) warfarin
d) clopidogrel
a) stop day before
b) stop day of (unless BD and morning surgery - can have afternoon dose)
c) 5 days before (bridge with LMWH)
d) 7 days before
85
Which type of anaesthetic drug can cause fasciculations?
Depolarising muscle relxanats e.g. Suxamethonium
86
Which term refers to the volume of air pushed in per breath during mechanical ventilation?
Tidal volume
87
What abdominal findings may be seen in tricuspid regurgitation? (2)
1) Pulsatile liver
2) Ascites
88
What is the name for treatment with a triple chamber pacemaker in severe heart failure with an ejection fraction of less than 35%? (1)
CRT
89
What pH is sufficient to confirm the placement of an NG tube?
<5
90
What is the recommended volume of maintenance fluids in adults?
25-30 ml/kg/day
91
How does diarrhoea affect the anion gap?
Does not affect anion gap
Causes normal anion gap metabolic acidosis
92
Mx of ischaemic stroke?
300mg aspirin daily for 2 weeks
75mg clopidogrel lifelong (or aspirin + dipyridamole if clopidogrel contraindicated)
93
What is a useful stategy for lowering ICP in cases of conservative management?
Hyperventilation
This results in decreased pCO2 --> vasoconstriction
94
What medication may be beneficial in the prophylactic treatment of cluster headaches?
Verapamil
95
Patients with which condition are particularly sensitive to non-depolarising agents (e.g. rocuronium)?
Myasthenia gravis
96
Which two factors contribute to the mean arterial pressure? (2)
1) Systemic vascular resistance
2) Cardiac output
97
Why should you avoid using hypotonic (0.45%) saline in paed patients?
Risk of hyponatraemic encephalopathy
98
Which are the main spinal tracts that carry pain signals through the spinal cord? (2)
1) Spinothalamic
2) Spinoreticular
99
At what dose of prednisolone do patients require hydrocortisone supplementation during surgery?
10mg or more
100
What enzyme is deficient in suxamethonium apnoea?
Acetylcholinesterase
101
What score can be used to predict mortality at time of admission to ICU?
APACHE score
102
What does inspiratory vs expiratory stridor indicate?
Inspiratory - laryngeal obstruction
Expiratory - tracheobronchial obstruction
103
Dose of nebulised ipratropium bromide given in acute severe asthma in adults?
0.5mg every 4-6 hours
104
Dose of prednisolone given in acute severe asthma in adults?
40-50mg
105
What AMTS score indicates confusion?
≤8, or new disorientation in person, place or time.
106
Mechanism of LA?
Block sodium channels
107
What amount of lidocaine dose 1% lidocaine contain?
1% lidocaine = 1g per 100ml
= 1000mg per 100ml
108
How many mg in a gram?
1000
109
Why should TPN be administered via a central line?
As it is strongly phlebitic
110
How much should OD insulin dose be reduced on day before and day or surgery?
Reduce by 20%
111
What should be used for pharmacological VTE prophylaxis in patients with CKD?
UH
112
How should DPP-4 inhibtiors (-gliptins) and GLP-1 analogues (-tides) be altered prior to surgery?
Keep taking as normal
113
Describe ASA grade VI
Declared brain dead - organ removal for donor purposes.
114
Calculation for serum osmolality?
2xNa + glucose + urea
115
What 2 diuretics can cause hyponatraemia?
1) thiazide
2) potassium sparing
116
What is ADH released in response to?
Increased serum osmolality
117
Who is primary polydipsia seen in?
(4)
1) Psychiatric disturbances
2) MDMA
3) Severe hypothyroidism
4) Glucocorticoid deficiency
118
The clinical features of hyponatraemia are primarily neurological.
Why?
Due to the effects of cerebral oedema
119
If the sodium is corrected too quickly in hyponatraemia, what is the patient at risk of?
Osmotic demyelination syndrome
120
How does osmotic demyelination syndrome typically present?
(2)
1) Quadriplegia
2) Pseudobulbar palsy
121
Management of hypervolaemic hyponatraemia?
Fluid restriction
122
Management of hypovolaemic hyponatraemia?
Rehydration with 0.9% saline
123
Management of SIADH?
Fluid restriction
124
How can serum glucose affect sodium?
Significant hyperglycaemia can cause hyponatraemia, often with raised serum osmolality.
125
How can hypothyroidism affect sodium?
Can cause hyponatraemia due to SIADH
126
How can NMS affect WCC?
Can cause raised WCC (leukocytosis)
127
What happens in COPD patients that receive too much O2?
Lose their hypoxic drive --> retain CO2 --> hypoventilate --> respiratory distress
128
Why does hypomagnesaemia need to be corrected before hypokalaemia?
As hypomagnesaemia prevents potassium absorption
129
What 3 electrolyte abnormalities can thiazide like diuretics cause?
1) hyponatraemia
2) hypokalaemia
3) hypercalcaemia
130
How can temp affect pancreas?
Hypothermia is a cause of acute pancreatitis
131
Correcting sodium levels rapidly is dangerous.
What is the risk of:
a) hyponatraemia correction
b) hypernatraemia correction
a) osmotic demyelination syndrome
b) cerebral oedema
132
Which diabetic drug can cause fluid retention?
Pioglitazone
133
1st line investigation in typical/atypical angina?
CT coronary angiography
134
How can acute pancreatitis affect calcium?
Can cause hypocalcaemia
135
What is the most common organism causng necrotising fasciitis (NF)?
GAS i.e. Strep. pyogenes
136
Which type of NF causes gas gangrene?
Type III
137
What classification system is used to guide management of cellulitis?
Eron classification
138
What is cellulitis an infection of?
Dermis + subcutaneous tissue
139
What Eron classification indicates admission for IV Abx in cellulitis?
III and IV
140
2 main organisms causing cellulitis?
GAS & S. aureus
141
1st line anticoagulation in DVT if patient has antiphospholipid syndrome?
LMWH
142
What pupillary defect may be seen in orbital cellulitis?
RAPD (indicates optic nerve involvement)
143
Abx of choice in cellulitis in penicillin allergic patients?
Erythromycin
144
Next step in DVT if proximal US scan is negative but d-dimer is positive?
Stop anticoagulation, repeat US scan in 1 week
145
Mx of a cyanide OD?
Hydroxocobalamin
146
Dose of morphine given in ACS?
1-10mg
Titrate according to patient's pain level.
147
What structure connects the 3rd & 4th ventricle?
Cerebral aqueduct
148
What is the most common cancer to spread to the brain?
Lung
149
Most malignant tyoe of a glioma?
Glioblastoma multiforme
150
What are glial cells?
These cells surround and support the neurones
151
Give 3 examples of glial cells?
1) Astrocytomas
2) Ependymal cells
3) Oligodendrocytes
152
Which cells regulate the circulation of CSF?
Ependymal cells
153
Where do ependymomas typically form?
4th ventricle
154
What layer do meningiomas arise from?
Arachnoid mater
155
What is the most common 1ary brain tumour in children?
Pilocytic astrocytoma
156
Most common location of brain tumours in adults vs paeds?
Adults: supratentorial
Paeds: infratentorial
157
Key histological feature of pilocytic astrocytoma?
Rosenthal fibres (corkscrew eosinophilic bundle)
158
What is the most common type of brain tumours?
Brain mets
159
Prognosis of a glioblastoma?
Around 1 year
160
What type of tumour is a glioblastoma?
Astrocytoma
161
Role of acetazolamide in idiopathic intracranial HTN?
Carbonic anhydrase inhibitor --> reduces CSF production --> reduces ICP
162
What may an ependymoma cause?
Hydrocephalus
163
Where are oligodendromas typically found?
Frontal lobes
164
What is the most aggressive paediatric tumour?
Medulloblastoma
165
How does a medulloblastoma spread?
Via CSF
166
What 2 medications can be used in pituitary tumours causing hormonal excess?
1) Bromocriptine (dopamine agonist)
2) Somatostatin analogue e.g. ocreotide
167
Give an example of a carbonic anhydrase inhibitor
Acetazolamide
168
What condition are haemangioblastomas associated with?
Von Hippel-Lindau syndrome
169
1st line pharmacological therapy for IIH?
Acetazolamide (carbonic anhydrase inhibitor)
170
What Abx are associated with idiopathic intracranial HTN?
Tetracyclines
171
What blood test can be done to confirm an anaphylactic reaction afterwards?
Serum tryptase within 6 hours
172
What antihistamines can be given in anaphylaxis?
Non-sedating antihistamines e.g. cetirizine (i.e. NOT chlorphenamine)
173
name a non-sedating antihistamine
cetirizine
174
name a sedating antihistamine
chlorphenamine
175
When can discharge be considered in anaphylaxis in those:
1) needing 1 dose of IM adrenaline
2) needing 2 doses of IM adrenaline
3) have previously had a biphasic reaction
4) also have severe asthma
5) present late at night
1) 2 hours after symptom resolution
2) 6 hours after symptom resolution
3) 6 hours after symptom resolution
4) 12 hours after symptom resolution
5) 12 hours after symptom resolution
176
Define refractory anaphylaxis
Not responded to 2x IM doses of adrenaline 5 mins apart.
177
Injection site for IM adrenaline in anaphylaxis?
Anterolateral aspect of middle third of thigh
178
IM adrenaline in paeds (6m to 6y)?
IM adrenaline 150mcg (0.15ml 1:1000)
179
IM adrenaline dose in anaphylaxis:
a) 6m to 6y
b) 6y to 11y
c) adults
a) 0.15ml 1:1000
b) 0.30ml 1:1000
c) 0.5ml 1:1000
180
What is the underlying cause of vision loss in temporal arteritis?
How does this look on fundoscopy?
Anterior ischaemic optic neuropathy --> caused by inflammation in the posterior ciliary artery (a branch of the ophthalmic artery) which leads to occlusion and subsequent ischaemia to the head of the optic nerve.
This leads to a swollen and pale optic disc with blurred margins.
181
What is Takayasu's arteritis?
A large vessel arteritis affecting younger females (10-40y).
It typically causes occlusion of the aorta and questions commonly refer to an absent limb pulse.
182
Why may a biopsy be normal in temporal arteritis?
due to skip lesions
continue steroids even if biopsy is negative
183
Features of optic neuritis?
- unilateral decrease in visual acuity over hours or days
- poor discrimination of colours, 'red desaturation'
- pain worse on eye movement
- relative afferent pupillary defect
- central scotoma
184
What investigation is diagnostic in most cases of optic neuritis?
MRI of the brain and orbits with gadolinium contrast
185
Mx of optic neuritis?
High dose steroids
186
mx of temporal arteritis:
a) vision affected
b) vision not affected
a) oral pred
b) IV methylprednisolone
187
'Double sickening' is associated with bacterial sinusitis.
What is this?
An initial period of recovery followed by a sudden worsening of symptoms.
It is thought to be caused by a 2ary bacterial infection following a viral rhinosinusitis.
188
What is the most common extra-renal manifestation of ADPKD?
Liver cysts (can cause hepatomegaly)
189
What cancer can PBC predispose to?
Cholangiocarcinoma
190
1 unit of blood should increase a patient's Hb by how much?
10 g/L
191
What is anaphylaxis caused by a blood transfusion thought to be the result of?
Can be caused by patients with IgA deficiency as they have anti-IgA antibodies.
IgA is found in most blood products.
192
What are the 2 main electrolyte abnormalities that can occur in blood transfusions?
1) Hypocalcaemia
2) Hyperkalaemia
193
What is irradiated blood depleted of?
T lymphocytes
194
What blood products should patients with IgA deficiency receive?
Washed blood products (IgA immunoglobulins have been removed)
195
What does the ABO blood system refer to?
Type of glycoproteins found on surface of RBCs
196
How may urine appear in acute haemolytic transfusion reaction?
Red (due to haemoglobinuria)
196
How can febrile nonhaemolytic transfusion reaction be avoided?
Leukoreduction (WBCs are removed from blood prior to transfusion)
197
What is the number 1 cause of death among all transfusion reactions?
TRALI
198
What can be given intraoperatively to reduce risk of PONV?
Dexamethasone
199
Mechanism of haloperidol?
D2 receptor antagonist
200
How soon before surgery can a baby breastfeed?
4 hours before
201
1st line for manipulation in adults & children?
Adults --> benzos
Children --> ketamine
202
What is next step in getting in an ET if 1st attempt unsuccessful?
Bougie
203
NG tube aspirate pH to be in the right place?
≤5
204
How to increase CO2 clearance on BIPAP?
1) Increase RR
2) Increase tidal volume (total volume of each breath) i.e. T insp
205
How to increase O2 delivery on BiPAP?
Increase PEEP and FiO2
206
Mx of HAP vs severe HAP?
Co-amoxiclav
Severe - tazocin
207
What investigations may be indicated in a PE?
1) ECG - sinus tachy, S1Q3T3
2) ABG - hypoxia, respiratory alkalosis (also required as most likely been put on O2)
3) Bloods - FBC, U&Es, coag, d-dimer, consider troponin/BNP
4) CXR - exclude alternative diagnosis
5) CTPA - imaging of choice
6) V/Q scan - in certain circumstances (e.g. pregnancy, renal impairment)
7) Echo - right heart strain
208
What is the Wells score?
Clinical probability of DVT
209
What is the PERC score?
A 'rule out' score for PE/DVT in low-risk patients
210
What is the PESI score?
Risk stratification to determine severity in patients with suspected/confirmed PE
211
What investigation is key before CTPA?
U&Es - look for any renal impairment
212
Why is coag blood test necessary in PE?
As likely to be put on anticoagulation
213
What score can be used to determine the severity of a PE?
PESI score (low = possible outpatient mx)
214
What anticoag should be used in PE in patients with CKD stage 5?
Warfarin
215
Is UH or LMWH indicated in renal failure?
UH
216
3 options for hyperacute mx of ischaemic stroke?
1) Thrombectomy - if presenting <6h, then aspirin 300mg 24h later
2) Thrombolysis - if presenting <4.5h, then aspirin 300mg 24h later
3) Aspirin 300mg alone (i.e. if not suitable for thrombectomy or thrombolysis)
217
Where must the clot be in an ischaemic stroke to qualify for thrombectomy?
There has been a LARGE vessel occlusion i.e. middle cerebral artery (most commonly)
218
When do patients with ischaemic stroke who have received thrombectomy or thrombolysis receive aspirin 300mg?
24h after (then continue for 2 weeks)
219
VTE prophylaxis following ischaemic stroke?
Intermittent pneumatic compression (IPCs) for the first 2 weeks.
LMWH VTE prophylaxis thereafter.
220
Why should LMWH VTE prophylaxis not be used for the first 2 weeks following ischaemic/haemorrhagic stroke?
As they are at increased risk of bleeding into that area in the brain.
221
A pneumothorax with a lung margin that is >2cm from the chest wall on CXR represents what % lung volume?
This represents a pneumothorax of 50% lung volume
222
Mx of CAP in patients with CURB-65 0-1?
Treat at home
Oral amoxicillin
223
What is an alterantive to oral amoxicillin in the mx of CAP?
Doxycycline or clarithromycin
224
Mx of CAP in patients with CURB-65 2?
Hospital
Oral amoxicillin
225
Mx of CAP in patients with CURB-65 3-4?
Hospital (consider HDU/ICU)
IV co-amoxiclav
226
