CRQ Paper 1 Flashcards
Question 1. Anton is a 32-year-old man who was found unconscious and brought to the Emergency Department. His past medical history includes craniopharyngioma (resected as a child) and a ventriculoperitoneal (VP) shunt. The neurosurgeon suspects the patient has hydrocephalus secondary to a blocked VP shunt. a) List two other possible neurological diagnoses based on the information above.
• Meningitis
• Seizure
• Intracranial haemorrhage
List two symptoms and four signs of an acute rise in intracranial pressure (ICP). (6 marks)
Symptoms:
• Early-morning headache/
headache which is exacerbated by
lying flat, coughing, sneezing,
bending over, straining
• Vomiting
• Blurred vision
• Diplopia
Signs:
• Papilloedema
• Seizures
• Decreased conscious level
• Bradycardia and hypertension
• Decerebrate posturing
• Fixed dilated pupils
• Hemiparesis
• Irregular respiration
• Death
I.e. the headache is
exacerbated by things that cause an acute rise in ICP
Usually in the absence ofnausea
As a result of papilloedema
As a result of ocular palsies
Papilloedema is a chronic and unpredictable sign.
This is the Cushing’s reflex.
Complete the following table regarding cerebrospinal fluid (CSF) flow. (5 marks)
- Ependymal cells of the choroid
plexus (accept either) - Third ventricle through foramina
of Monro (need both for 1 mark) - Fourth ventricle through aqueduct
of Sylvius (accept canal of Sylvius
or cerebral aqueduct) (need both
for 1 mark) - Through foramina of Luschka and
Magendie (need both for 1 mark) - Arachnoid granulations
Namethree roles of CSF. (3 marks)
Buoyancy
** The low specific gravity of CSF reduces the effective weight of the brain from
1.4 kg to just 47 g.
• Protection Fluid buffer acts as a shock
absorber from some forms of
mechanical injury.
• CSF displacement to compensate
for raised intracranial pressure
Displacement of CSF into the spinal canal is an important compensatory mechanism when ICP is raised.
• Provides a constant chemical and ionic environment for neurons
• Acid–base regulation for control of respiration
• Clearing waste
The neurosurgeon suspects that the VP shunt is infected and removes it. She inserts an external ventricular drain (EVD) to relieve the raised ICP and prescribes a setting of +15 cmH2O. How would you set up the collecting burette? (2 marks)
Set the zero level to the same
horizontal level as the foramen of
Monro (accept external auditory
meatus).
1 This is equivalent to the
external auditory meatus
when supine.
• Set the drainage level: move the
drip chamber to align with the
+15 cmH2O marking.
List two complications associated with EVDs. (2 marks)
• Haemorrhage Any 2
• Infection
**This is the most feared complication: incidence of 5%–20% and high mortality.
• Seizure
• Sub-optimal placement/
displacement/blockage of catheter
David, a 56-year-old man, is listed for elective repair of a large incisional hernia. He has a background history of dilated cardiomyopathy. a) Complete the following table (with low, normal or high) describing the pathological features of the three World Health Organization–recognised types of cardiomyopathy. (3 marks)
Need both elements correct for 1
mark
Dilated:
Stroke volume: low
Contractility: low
Hypertrophic:
Cardiac output: low
Contractility: high
Restrictive:
Cardiac output: normal or low
Stroke volume: low
Although most commonly idiopathic, list three other causes of dilated cardiomyopathy. (3 marks
• Ischaemic
• Valvular disease
• Post-viral
• Peri- and post-partum
• Post-chemotherapy
• Sickle cell disease
• Alcoholism
• Hypothyroidism
• Muscular dystrophy
At the pre-operative clinic, David’s symptoms of heart failure appear to be well controlled, and his chest is clear on auscultation.
ipril daily and last attended cardiology clinic more than 12 months ago. c) List three investigations you would request prior to listing David for his elective procedure. (3 marks)
• Urea and electrolytes (due to ACE
inhibitor therapy)
• ECG
• Transthoracic echocardiography
• Full blood count
Following relevant investigations, David proceeds to surgery. d) Aside from AAGBI-recommended standard monitoring, what further monitoring and access would you instigate prior to anaesthetising David for his incisional hernia repair? (Dilated cardiomyopathy)(3 marks)
Five-lead ECG
• Invasive arterial blood pressure
monitoring
• Central venous access
• Cardiac output monitoring
State the principles by which you would manage his cardiovascular physiology intra-operatively (Dilated cardiomyopathy). (5 marks)
Avoid tachycardia
• Maintain preload/
normovolaemia
• Avoid negative inotropy/provide
inotropic support
• Avoid increases in systemic
vascular resistance (SVR)
• Maintain afterload/mean arterial
pressure (accept avoid reduction
in SVR)
• Maintain sinus rhythm/rapid
treatment of arrhythmias
• Intra-operative correction of
deranged electrolyte levels
Yourconsultant suggests performing an epidural block for David’s surgery dueto thesize of the hernia. f) List two advantages and one disadvantage of neuraxial blockade specific to cardiovascular physiology in dilated cardiomyopathy. (3 marks)
Advantages:
• Reduced risk of tachycardia
• Avoidance of increased SVR
• Reduction in SVR may increase
cardiac output
(accept ‘reduces sympathetic
response to pain’ for 1 mark)
Disadvantage:
• Reduced coronary perfusion with
reduction in diastolic BP
• Treatment of any hypotension
with intravenous fluids increases
risk of pulmonary/peripheral
oedema
Any 2
Any 1
Reducing afterload may
improve cardiac output;
however, hypotension must
be avoided due to the risk of
myocardial hypoperfusion.
Remember that SVR and
afterload are not the same –
afterload relates to
ventricular internal fibre
load during systole and is a
combined effect of SVR
alongside the left ventricle
chamber pressure,
dimensions and wall
thickness. Dilated ventricles
have an increased afterload.
Question 3.
Rachel is a 53-year-old woman who has spent 10 days ventilated on the Intensive Care Unit (ICU) for a community-acquired pneumonia. She is weaning from mechanical ventilation, having had a tracheostomy sited. However, you notice she appears weak and struggles to lift her arms.
a) Define ICU-acquired weakness (ICUAW). (1 mark)
Clinically detectable weakness in a
critically ill patient in whom there is no plausible aetiology other than critical illness
b) List the three classes of ICUAW. (3 marks
Critical illness polyneuropathy (CIP)
Critical illness myopathy (CIM)
Critical illness neuromyopathy
(CINM)
List six risk factors for the development of ICUAW. (6 marks)
Female sex
• Increasing age
• Sepsis and septic shock
• Multi-organ failure
• Drug-induced encephalopathy
• Increasing duration of acute illness and immobility
• Increasing duration of mechanical ventilation
• Requirement for parenteral nutrition
• Hypoalbuminaemia
• Hyperglycaemia
• Use of high-dose steroids
• Neuromuscular blocking agents
• Vasopressors
**The risk of CIM increases with the duration of neuromuscular blockade and corticosteroid use.
List four clinical features of ICUAW. (4 marks)
• Onset after the acute ICU admission
• Generalised, symmetrical weakness
• Sparing of the facial muscles/cranial nerves
• Difficulties weaning from ventilatory support
• Reduced reflexes
• Normal conscious level
• Medical Research Council power score less than 48
• Autonomic function is not affected
**Extra-ocular muscle involvement is rare and
suggests an alternative diagnosis.
.
List four clinical investigations that aid the diagnosis and differentiation of ICUAW. (4 marks)
○ Creatine kinase
○ Nerve conduction studies
○ Electromyography
○ Muscle biopsy
**Lumbar puncture, erythrocyte sedimentation rate and autoantibodies are
often requested to exclude
other diagnoses.
What proportion of patients diagnosed with ICUAW will die during their hospital admission? (1 mark)
45%
What proportion of patients who survive their hospital admission will achieve a complete recovery? (1 mark)
68%
Question 4. You review Frank, a 3-year-old boy on your day-case list who will be undergoing a circumcision. He weighs 15 kg. His parents want to discuss analgesia and have read an information leaflet about caudal analgesia. a) List four other analgesic options that could be considered in this case. (4 marks)
Paracetamol
• Non-steroidal anti-inflammatory
drugs
• Opioids (e.g. morphine)
• Topical local anaesthetic
• Local anaesthetic infiltration
• Specific penile block
b) Complete the labels (i–vi) on the following figure. (3 marks)
i = sacrococcygeal membrane (accept
sacral hiatus)
ii = epidural/caudal space
iii = subarachnoid space
iv = spinal cord
v = dura mater
vi = filum terminale
Where does the dural sac normally end in a child of this age? (1 mark)
Dural sac ends at S2 (accept S1) 1 The spinal cord ends at L1/2
in adults and children, and
at L3 in an infant
List four complications of caudal blockade. (4 marks)
• Intravascular injection/local
anaesthetic toxicity
• Intrathecal injection/accidental
spinal anaesthesia
• Hypotension
• Block failure (accept
subcutaneous injection
State the name, concentration and volume of local anaesthetic agent you would use for the caudal in this case, according to the Armitage ‘rules’.
Name = bupivacaine
Concentration = 0.25%
Volume = 0.5 mL/kg = 7.5 mL
For circumcision surgery, a sacro-lumbar block is sufficient, i.e. 0.5 mL/kg.
**Amid-abdominal block is achieved using 1 mL/kg and a mid-thoracic block by using 1.2 mL/kg of 0.25% bupivacaine.
List two drugs (with doses) that could be added to your local anaesthetic mixture to prolong the duration or quality of the block. (2 marks)
• Fentanyl 1–2 μg/kg = 15–30 μg
• Clonidine 1–2 μg/kg = 15–30 μg
• Preservative-free ketamine
0.5 mg/kg = 7.5 mg
Following surgery, the recovery nurse is concerned that Frank is in pain. List three methods of assessing pain in a child of this age group, 3yrs. (3 marks)
• Physiological (HR, BP, RR)
• Behavioural
• Self-reporting scales (Piece of
Hurt scale/Faces pain scale)
• Parent/carer reporting
Question 5. Lorna is a 30-year-old nulliparous woman on the maternity unit. She has been classified as ‘high risk’ and is on continuous cardiotocography (CTG) monitoring. a) List three features of the foetal heart rate (FHR) that are interpret CTGtraces. (3 marks)
• Baseline (beats/minute)
• Baseline variability (beats/minute)
• Decelerations
**Each feature is described as reassuring, non-reassuring or abnormal.
Following review of the CTG, theobstetric team decides to take a foetal blood sample (FBS). c) Complete the following table regarding the classification for FBS results. (6 marks)
pH:
Normal: 7.25 or above
Borderline: 7.2–7.25
Abnormal: 7.2 or below
Lactate:
Normal: 4.1 mmol/L or below
Borderline: 4.2 to 4.8 mmol/L
Abnormal: 4.9 mmol/L or above
**Be aware that for women with sepsis or significant meconium, foetal blood samples may be falsely
reassuring
Despite all pharmacological attempts to make Ian comfortable, he remains in pain. d) List three regional anaesthetic techniques that could provide analgesia in this case rib #, and for each technique, give one advantage and one disadvantage. (9 marks)
Regional anaesthetic technique
1. Thoracic epidural
○Advantage: excellent analgesia
○Disadvantage: technically difficult to
insert; risk of dural puncture/spinal cord injury; hypotension
2. Paravertebral block
○Advantage: fewer side effects, e.g. hypotension; can cover up to five levels with one paravertebral catheter
Disadvantage: risk of epidural spread, pneumothorax
3. Serratus plane block
Advantage: superficial block; performed with patient supine; can be inserted in anticoagulated patients
Disadvantage: pneumothorax;
vascular puncture regional techniques have fewer side effects and offer near-equivalent analgesia
**Not acceptable: interpleural block or intercostal block higher risk of local anaesthetic toxicity
Epidural analgesia has traditionally been used to manage more complex rib fractures.
However, many trauma patients are
multiply injured, and adequate positioning, hypotension and coagulopathy remain prime concerns.
Question 7. Bronagh is an 86-year-old woman admitted for an elective total hip replacement due to osteoarthritis, which you opt to perform under spinal anaesthesia. She has a background history of hypertension. During the procedure, there is a sudden change in her observations associated with cementing of the hip joint. a) Complete the following table defining grades one and two of bone cement implantation syndrome (BCIS). (6 marks)
Grade 1:
<94% O2 saturations
>20% reduction in systolic BP
No change in conscious level
Grade 2:
<88% O2 saturations
>40% reduction in systolic BP
Loss of consciousness
3
3
BCIS occurs around the
time of cementation,
prosthesis insertion,
reduction of the joint or
(rarely) deflation of the
tourniquet in patients
undergoing cemented bone
surgery.
List the defining feature of grade 3 BCIS. (1 mark)
Cardiovascular collapse/
cardiopulmonary resuscitation
List six symptoms of hyperthyroidism. (6 marks
• Agitation/restlessness
• Anxiety
• Fine tremor
• Weight loss despite increased appetite
• Tachycardia/palpitations/atrial fibrillation
• Intolerance to heat
• Sweating
• Diarrhoea
• Palmar erythema
• Proximal myopathy
• Hair loss (especially outer third of eyebrow)
• Oligomenorrhoea
• High output cardiac failure
Not acceptable: Graves’
ophthalmopathy symptoms/
signs or pretibial myxoedema, as these are specific to Graves’ disease and not hyperthyroidism.
Many of the clinical features of hyperthyroidism can be accounted for by a TSH-induced upregulation of β1-receptors and an increase in basal metabolic
rate. β-blockers may be helpful to control
tachycardia, palpitations and tremor.
Question 10. Laura is a 75-year-old woman who is due to undergo electroconvulsive therapy (ECT) for severe depression.
a) For each psychoactive drug that the patient is taking, as listed in the table below, state the
drug class (in full) and a drug interaction of relevance to anaesthetists. (6 marks)
Fluoxetine:
Class: selective serotonin reuptake
inhibitor
Interaction: tramadol or pethidine may precipitate serotonin syndrome
Amitriptyline:
Class: tricyclic antidepressant
Interaction: potentiation of the effect of indirectly acting sympathomimetics
Phenelzine:
Class: monoamine oxidase inhibitor
Interaction: profound pressor response following administration of directly and indirectly acting sympathomimetics
Patients presenting for ECT
have, by definition, severe
depression. Many patients
take a combination of many
psychoactive drugs, some of
which have a significant
bearing on anaesthetic
management.
