This page intentionally left blank SBAs for the Final FRCA SBAs for the Final FRCA Dr James Nickells FRCA Dr Tobias Everett FRCA Dr Benjamin Walton FRCA North Bristol NHS Trust Bristol CAMBRIDGE UNIVERSITY PRESS Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, São Paulo, Delhi, Dubai, Tokyo Cambridge University Press The Edinburgh Building, Cambridge CB2 8RU, UK Published in the United States of America by Cambridge University Press, New York www.cambridge.org Information on this title: www.cambridge.org/9780521139489 © J Nickells, T Everett and B Walton 2010 This publication is in copyright Subject to statutory exception and to the provision of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of Cambridge University Press First published in print format 2010 ISBN-13 978-0-511-71271-5 eBook (NetLibrary) ISBN-13 978-0-521-13948-9 Paperback Cambridge University Press has no responsibility for the persistence or accuracy of urls for external or third-party internet websites referred to in this publication, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate From James To my lovely girls, Jasna, Kasia and Roxy From Toby To my magnificent wife, Claire, for her consistent love and support and our wonderful daughters, Iris and Coralie From Ben To my children, Joseph and Isabella, and my grandfathers, Samuel Basil Turner and George Walton Contents Preface page ix SBA FAQs QUESTION PAPERS Paper A 11 Paper B 29 Paper C 47 Paper D 66 ANSWERS 85 Paper A 87 Paper B 88 Paper C 89 Paper D 90 EXPLANATIONS 91 Paper A 93 Paper B 141 Paper C 190 Paper D 240 Index 292 vii Paper D ventilation A left- or right-facing double lumen tube may ventilate either the right or left lung A left-facing double lumen tube is preferred to avoid the challenge of aligning the right upper lobe bronchus with the side hole of the right-facing tube In fact there are very few absolute indications for using a right-facing tube The size and depth of double lumen tubes is best judged from the patient’s height, not weight For an adult male of 170 cm height a 39 French tube at 29 cm would be a sensible starting point For every 10 cm (of patient height) below this, a sequentially smaller sized tube should be selected and depth reduced by cm For a patient of 180 cm height, a 41 French tube might be inserted to 30 cm Alternative tube sizes must be available and the depth fine tuned for optimal positioning The bronchial cuff should be inflated with the minimal volume of air that will prevent the ventilation of one lung interfering with that of the other This may be as little as mL Pendelluft describes the situation where lung units have different compliance or resistance (and hence time constants), such that emptying of one region of lung may result in the distension of another region rather than egress of gas through the trachea Thus gas passes ‘to and fro’ rather than ‘in and out’ Question 287: Collapsing pulse A 73-year-old patient requires emergency laparotomy During their preoperative assessment they are noticed to have a collapsing pulse Which of the following conditions is LEAST likely to be the cause of this finding? a) b) c) d) e) An undiagnosed patent ductus arteriosus Hyperthyroidism Mixed aortic valve disease Haemoglobin 8.2 g/dL Temperature 38.5 °C Answer: c Explanation A collapsing or ‘water hammer’ pulse is classically seen in patients with aortic regurgitation (AR) although it is sometimes seen in patients with a hyperdynamic circulation (e.g thyrotoxicosis, Paget’s disease, anaemia or pyrexia) Mixed aortic valve disease will not give a collapsing pulse because the stenotic valve prevents the rapid retrograde flow that would otherwise be responsible for the nature of the pulse A patent ductus arteriosus may be entirely asymptomatic or may present with shortness of breath, tachyarrhythmias, cardiomegaly and a continuous machine-like murmur as well as a collapsing pulse The most common cause of AR in developing countries is rheumatic heart disease with clinical presentation in the second or third decade In the developed world, severe AR is most frequently due to diseases that are either congenital (e.g bicuspid aortic valve) or degenerative (e.g anuloaortic ectasia) and presentation is usually between the fourth and sixth decades Severe AR is clinically more often observed in men than in women In addition to the collapsing pulse, the regurgitant diastolic flow combined with an increase in systolic stroke volume causes a widened pulse pressure Aortic regurgitation is unique among valvular heart disease as it causes both left ventricular volume overload and pressure overload Due to a late increase in left atrial pressure symptoms, features such as dyspnoea and angina usually develop slowly General aims in the anaesthetic management of a patient with AR should include prevention of bradycardia, adequate volume loading, low systemic vascular resistance and maintenance of myocardial contractility Reference 282 Enriquez-Sarano M, Tajik AJ Clinical practice Aortic regurgitation New Engl J Med 2004; 351(15): 1539–46 An intravenous drug abuser has been brought into the emergency department (ED) in cardiac arrest secondary to ventricular fibrillation resistant to DC cardioversion Assistance from the intensive care team is sought The patient has had his trachea intubated, without drugs, by the paramedics; however, they and the ED physicians have been unable to secure intravenous access The following drugs may be given via the intratracheal route EXCEPT which one? a) b) c) d) e) Paper D Question 288: Intratracheal drugs Adrenaline Lidocaine Amiodarone Naloxone Atropine Answer: c Explanation Intratracheal drug administration is suboptimal by virtue of its unpredictability Theoretically absorption is intra-alveolar so the drug must be diluted up to around 10 mL with 0.9% saline and vigorously injected into the endotracheal tube Alternatively, an infusion line may be introduced into the endotracheal tube as far as the carina and the preparation injected through this Hyperventilation should follow to encourage intra-alveolar dispersion There is no consensus on necessary dose due to the variable absorption, but encountered dose ranges are: adrenaline to mg, lidocaine 50 to 100 mg, naloxone 0.4 to 5.0 mg, atropine to mg Although amiodarone might be useful here, in a case of persistent ventricular fibrillation resistant to DC cardioversion, intrapulmonary amiodarone (in rats) causes rapid inflammation and prompt fibrosis so cannot be administered via the intratracheal route Reference Maddocks J, Yurdakök M, Erdem G Intratracheal drugs Lancet 1988; 331: 1276–7 Question 289: Harmful drugs in the intensive care unit A sick septic patient is admitted to the intensive care unit (ICU) and at day two, the following drugs can be found on his drug chart Which of them is statistically MOST LIKELY to cause him harm during his stay on the ICU? a) b) c) d) e) Noradrenaline Morphine Gentamicin Propofol Insulin Answer: a Explanation In 2008, a review of 12 084 incidents reported to the National Patient Safety Agency in a previous six-month period were reviewed Drug-related incidents producing harm were identified In this study, the drug most commonly reported in a critical care environment was morphine However, relatively fewer of these reports were thought to have actually caused patient harm There were 55 incidents of harm with noradrenaline followed by 48 with insulin 283 Paper D Reference Thomas A, Panchagnula U Medication-related patient safety incidents in critical care: a review of reports to the UK National Patient Safety Agency Anaesthesia 2008; 63(7): 726–33 Question 290: Carotid endarterectomy Regarding awake carotid endarterectomy, which one of the following statements is TRUE? a) Superficial and deep cervical plexus blocks are necessary for regional anaesthesia in the awake patient undergoing carotid endarterectomy b) It is common to use an intermittent bolus sedation technique during clamping of the carotid c) One advantage of the awake technique is that it obviates the need for a shunt d) Agitation is common and should prompt reassurance of the patient e) Chronic obstructive pulmonary disease may be a relative contraindication to the awake technique Answer: e Explanation Of paramount importance during carotid endarterectomy is maintaining cerebral perfusion pressure and adequate oxygen delivery to all regions of the cerebrum throughout the procedure Despite various technologies that allow us to infer this in the anaesthetised patient it is arguable that there is not one as reliable as being able to monitor the awake patient’s cerebration during the operation The advantages and disadvantages of awake carotid endarterectomy makes a good short answer question Many vascular anaesthetists use just a superficial cervical plexus block along with surgeon infiltration of local anaesthetic intra-operatively An intermittent bolus technique is ill advised, especially while the carotid is clamped, because a reduction of conscious level might be falsely attributed to this where cerebral hypoperfusion is the culprit (or vice versa) The awake technique alerts us to the need for a shunt but does not obviate it Agitation is a common manifestation of cerebral hypoperfusion and should prompt further assessment Management of agitation including reassurance should occur only once ischemia has been eliminated The anaesthetist would usually consider regional anaesthesia in a patient with COPD in whom a general anaesthetic might pose a higher risk The converse is sometimes true with carotid endarterectomy The patient must be able to lie still and fairly flat without moving or coughing unpredictably Many patients with COPD may not satisfy this requirement A continuous infusion technique for sedation may lead to carbon dioxide retention with a sudden large gasp disrupting surgery Also the phrenic nerve block associated with cervical plexus block may cause an unacceptable degree of respiratory embarrassment Question 291: Autonomic dysreflexia Eight months following a road traffic accident in which a 30-year-old man sustained a spinal cord injury, the same patient presents for surgery to treat a urethral stricture Regarding potential autonomic dysreflexia (AD), the following statements are true EXCEPT which one? 284 a) A blood pressure of 120/80 mmHg would be inconsistent with a diagnosis of AD b) Injuries below the sixth thoracic vertebra (T6) and incomplete spinal cord lesions are less likely to lead to AD than lesions above T6 and complete spinal cord lesions Paper D c) Signs include flushed, sweaty skin above the level of the lesion and cool, pale skin below this level d) Both tachycardia and bradycardia are commonly seen during an episode of AD e) The most common triggers for episodes of AD are stimulation of the lower urinary tract or bowel distension secondary to faecal impaction Answer: a Explanation Autonomic dysreflexia usually occurs following complete or incomplete spinal cord injury above the level of T6 It may also occur following lower spinal cord lesions but symptoms are much milder Presenting symptoms include headache, sweating above the level of the injury, nasal congestion, malaise, nausea and blurred vision Signs include flushed, sweaty skin above the level of the lesion and cool, pale skin below this level Blood pressure is elevated but it is important to note that resting blood pressure is usually lower following spinal cord injury, hence a blood pressure of 120/80 mmHg would still be consistent with a diagnosis of AD During episodes of AD systolic blood pressures and diastolic blood pressures as high as 300 and 220 mmHg respectively have been reported Reflex bradycardia secondary to vagal stimulation is often seen but tachycardia is also common Autonomic dysreflexia is caused by spinal reflex mechanisms that remain intact despite the patient’s injury, and is precipitated by a noxious stimulus that produces an afferent impulse generating a generalised sympathetic response Stimulation of the lower urinary tract and bowel distension secondary to faecal impaction account for the majority of precipitants With lesions at or above the T6 level, the splanchnic vascular bed becomes involved, which provides the critical mass of blood vessels required to cause the elevation in blood pressure In a person without spinal cord injury, descending inhibitory pathways would respond to the rise in blood pressure and modulate the sympathetic response However, the injury to the spinal cord prevents such signals from descending to the sympathetic chain The end result of this unopposed sympathetic activity is peripheral and splanchnic vasoconstriction During labour and delivery, the risk of autonomic dysreflexia in patients with lesions at or above T6 may be up to 90% The early use of neuraxial blocking techniques reduces this risk considerably Reference Blackmer J Rehabilitation medicine: Autonomic dysreflexia Can Med Assoc J 2003; 169(9): 931–5 Question 292: Neonatal neurological physiology Regarding neonatal physiology, which one of the following statements is TRUE? a) b) c) d) e) A neonate has low levels of endorphins compared to adults A neonate has mature neuromuscular junctions by two weeks of age A neonate has reversed direction of flow of CSF compared to adults A neonate has blunted parasympathetic reflexes A neonate has poor sympathetic response to bleeding Answer: e Explanation The physiology of groups such as the elderly, the pregnant or neonates is a rich source of questions for the examiner There is therefore no getting away from learning all the important differences of the major body systems Neonates have high levels of endorphins and encephalins They have immature neuromuscular junctions, poor sympathetic response to bleeding and brisk vagal reflexes 285 Paper D Question 293: Osmolality Regarding osmolality, the following statements are true EXCEPT which one? a) Raoult’s law applies to one of the colligative properties of solutions b) Plasma osmotic pressure is approximately atmospheres c) One mole of a substance dissolved in one kilogram of solvent will produce a freezing point depression of 1.86°C d) Plasma osmolality may be estimated from a patient’s urea and electrolytes, and their blood glucose e) An osmolality gap may be observed following transurethral resection of the prostate Answer: c Explanation When a solute is added to a solvent, it predictably alters the solvent’s physical characteristics It will cause a depression of vapour pressure and freezing point and an elevation of its boiling point and osmotic pressure These are called the colligative properties of solutions Raoult’s law simply states that the depression in solvent vapour pressure is proportional to the molar concentration of added solute An osmole refers to the number of osmotically active particles liberated in solution not the molar concentration of the solute For example the molar concentration of a bag of 0.9% saline is 154 mmol/L, but as the ionic compound NaCl dissociates into two moieties (Na+ and Cl−), the osmolality of the solution is 308 mOsm/kg Note that osmolality is per kilogram of solvent Osmolarity (osmoles per litre of solution) is less useful clinically given the huge range of molecular sizes in plasma Osmolality may be estimated (2 × [Na−] + [Urea] + [Glucose]) or measured using any of the colligative properties of solutions, although most practically it is done via measurement of depression of the freezing point One osmole of a substance dissolved in one kilogram of water will produce a freezing point depression of 1.86 °C, a boiling point elevation of 0.52 °C, a vapour pressure decrease of 0.04 kPa and an osmotic pressure of 2300 kPa (or 23 atmospheres!) It can be seen now that plasma osmolality of around 300 mOsm/ kg is indeed around atmospheres (0.3 × 2300 = 690 kPa) Avoid confusion with plasma oncotic pressure which is about 3.3 kPa (25 mmHg) and used with Starling forces calculations Absorbed glycine during transurethral resection of the prostate causes an osmolality gap Question 294: Acid–base management during cardiopulmonary bypass Regarding acid–base management during cardiopulmonary bypass, which one of the following statements is TRUE? a) The solubility of carbon dioxide decreases as the temperature decreases b) The ‘alpha’ of alpha-stat pH management refers to the alpha-globin subunit of haemoglobin c) On cardiopulmonary bypass without correction, as the temperature falls, the pH of the blood falls d) In alpha-stat management, carbon dioxide must be added to the bypass circuit e) In pH-stat management, the arterial blood gas values are corrected for the temperature the patient was when they were taken 286 Answer: e During cardiopulmonary bypass (CPB) a degree of therapeutic hypothermia is employed Henry’s law states that at a given temperature the quantity of gas dissolved in a liquid is directly proportional to the partial pressure of the gas in equilibrium with that liquid solvent As temperature falls the solubility of a gas in a liquid increases If the solvent is in contact with the gas to be dissolved then as the temperature drops a greater quantity of gas dissolves – the content increases and the partial pressure remains the same If the solvent is in a closed container without contact with the gas in question, then as the temperature falls the content remains the same However, a proportion of the gas previously exerting a gas tension now dissolves and its partial pressure falls This is the case in vivo, which can be considered akin to this closed container as basal metabolic rate contributes an unchanging and finite quantity of carbon dioxide to the blood Recalling the determinants of blood pH it follows that as temperature falls and PaCO2 falls, pH rises PaCO2 is an important determinant of cerebral blood flow, while pH is important for satisfactory enzymatic function In essence, which of these we prioritise determines our choice of alpha-stat or pH-stat management during the hypothermia of CPB The gas electrodes in the arterial blood gas analyser are held at 37 °C In pH-stat measurement a correction factor is used to compensate for the temperature of the patient (and therefore sample), then carbon dioxide is added to the CPB blood to render the pH 7.4 at that body temperature – total body carbon dioxide increases Cerebral autoregulation is lost and cerebral blood flow becomes directly proportional to the cerebral perfusion pressure Cerebral blood flow is greater than with alpha-stat and microemboli risk is higher In alpha-stat management there is no correction for patient temperature It is assumed that if the pH:PaCO2 ratio is acceptable at 37 °C then that ratio is acceptable at whatever the temperature it was taken This retained ratio means enzyme activity is maintained Cerebral autoregulation is preserved (although the graph is down- and left-shifted) In most cases, alpha-stat management is used Alpha refers to the alpha imidazole group on the intracellular protein histidine Its degree of ionisation remains constant despite a change of temperature Paper D Explanation Question 295: Poisoning A 35-year-old woman is admitted confused and vomiting to the emergency department following ingestion of a quantity of unknown tablets The critical care team is called because of the following blood gas result: pH 7.55; pO2 19.02 kPa; pCO2 2.53 kPa; HCO3− 18 mmol/L Of the following drugs, which has MOST LIKELY been ingested? a) b) c) d) e) Paracetamol Dothiepin Aspirin 3,4-methylenedioxymethamphetamine (MDMA) Cocaine Answer: c Explanation The blood gas shows a mixed picture of a respiratory alkalosis and a metabolic acidosis This is classically seen in salicylate overdose The metabolic acidosis is due to a number of mechanisms including ketoacidosis via the stimulation of lipolysis, the uncoupling of oxidative phosphorylation and hence increased hydrolysis of ATP producing more H+ and interference with the tri-carboxylic acid cycle The respiratory 287 Paper D alkalosis is due to the direct stimulation of the respiratory centre The clinical features of salicylate poisoning depend on the dose ingested Severe overdose may lead to respiratory depression and even apnoea when the blood gas result will obviously be different Neurological features include agitation, confusion, tinnitus, lethargy and coma Pulmonary oedema may occur, which is non-cardiogenic in origin Cardiovascular instability may be due to dysrhythmias especially those related to hypokalaemia Nausea, vomiting and abdominal pain are common Salicylate levels may be misleading as absorption of aspirin can be slow, so plasma salicylate concentration may continue to rise for several hours Also, plasma salicylate level tends not to correlate well with clinical severity, particularly at extremes of age Despite this, the clinical severity of poisoning is low below a plasma salicylate level of 500 mg/L (3.6 mmol/L) Activated charcoal can be given within one hour of ingesting more than 125 mg/kg of aspirin Treatment with intravenous sodium bicarbonate may be given to enhance urinary salicylate excretion (forced alkaline diuresis) Haemodiafiltration may be useful in severe salicylate poisoning, for example in the presence of a severe metabolic acidosis Question 296: Prophylaxis following splenectomy A 50-year-old lady has undergone emergency splenectomy following a road traffic accident Regarding her follow-up care the following statements are correct EXCEPT which one? a) She should receive pneumococcal vaccination against Streptococcus pneumoniae approximately two weeks after her splenectomy b) If not previously immunised she should be vaccinated against Haemophilus influenzae type B c) Influenza vaccination is recommended for her on a yearly basis d) She should be immunised against Neisseria meningitidis e) She should receive ongoing prophylactic antibiotics to reduce the chance of serious infection with Staphylococcus Answer: e Explanation 288 Reduced post-splenectomy levels of opsonins, splenic tuftsin and immunoglobulin (IgM) (which promote phagocytosis of particulate matter and bacteria), as well as the loss of the spleen’s ability to mechanically filter blood, hamper the body’s ability to clear some infecting organisms Post-splenectomy patients are at particularly increased susceptibility to infection from encapsulated organisms, some Gram-negative rods, protozoa and possibly some yeasts The predominant infecting organisms are pneumococcus (50 to 90% of all infections), Neisseria meningitidis and Haemophilus influenzae hence vaccination against all three of these is recommended The risk of infection is highest in young children, particularly in those with sickle cell disease In addition to vaccinations, antibiotic prophylaxis against Streptococcus (group B streptococcus is another example of an encapsulated organism) is currently recommended for life Immunisation should ideally take place two weeks before planned splenectomy but in the emergency setting should happen approximately two weeks after Timing of vaccine administration following splenectomy is, however, open to debate Of concern is the patient’s immunogenicity in the peri-operative period and their impaired immune function while critically ill The patient’s present state of health should be considered prior to the administration of post-splenectomy vaccines In patients with moderate to severe acute illness, vaccination should be delayed until the illness has resolved This minimises adverse effects of the vaccine, which could be more severe in the presence of illness or could confuse the patient’s clinical picture (such as a postvaccine fever) Davies J, Barnes R, Milligan D Update of guidelines for the prevention and treatment of infection in patients with an absent or dysfunctional spleen J Royal Coll Phys Lon 2002; 2(5): 440–3 Paper D Reference Question 297: Pulmonary aspiration A patient aspirates their stomach contents on emergence from anaesthesia while lying supine They receive mechanical ventilation on ICU and are successfully weaned and extubated but still need supplementary oxygen At day 12, they develop raised inflammatory markers, a temperature of 39.5°C and evidence of pulmonary abscesses on their plain chest radiograph Which one of the following is the MOST LIKELY site of their abscess? a) b) c) d) e) Superior segment of the right lower lobe Superior segment of the lingular Superior segment of the left lower lobe Posterior basal segment of the right lower lobe Lateral segment of the right middle lobe Answer: a Explanation This question tests knowledge of the anatomy and orientation of the tracheobronchial tree Aspirate tends to pool in the dependent segment therefore the likely site of abscess depends on the patient’s position at time of aspiration and consideration of into which of the segmental bronchi gravity might direct the aspirate This is only a probability of course, but the question asks for the most likely site In the supine position aspiration tends to favour the superior segment of the right lower lobe If in the right decubitus position, aspiration will most likely affect the posterior segment of the right upper lobe (or sometimes quoted as the lateral segment of the right middle lobe) In the left decubitus position the lingular is the most likely destination and if the patient is erect, one would expect pooling in the posterior basal segment of the right lower lobe Question 298: Postoperative urinary retention The following features would place a patient at risk of postoperative urinary retention EXCEPT which one? a) b) c) d) e) Male gender 500 mL intravenous infusion of Hartmann’s solution during knee arthroscopy Previous history of severe bradycardia under anaesthesia Open reduction and mesh repair of inguinal hernia Intravenous midazolam sedation in recovery Answer: b Explanation Postoperative urinary retention (POUR) is the inability to void in the presence of a full bladder The incidence has been reported as anything from to 70% As fewer patients are now catheterised in the peri-operative period it has become increasingly important to be able to recognise and treat POUR It is therefore useful to understand who might be at higher risk of POUR Patients over 50 years old have a 2.4 times greater risk of POUR than under 50s, and males have a 1.6 times greater risk than females Patients having hernia repair or anorectal surgery or who have previously had pelvic surgery 289 Paper D are at risk Pre-existing obstructive urinary symptoms or the presence of neurological diseases such as alcoholic neuropathy, a cerebral or spinal lesion or diabetes also put the patient at risk, as does preoperative treatment with α- or β-blockers Intraoperative risk factors include intravenous anticholinergic agents, intravenous infusion of more than 750 mL of fluid to patients having high-risk operations, long duration of surgery and spinal or epidural blockade Features of a spinal making it particularly high risk include using high-dose, long-acting local anaesthetic or using opioids that are hydrophilic (such as morphine), have high mu-receptor selectivity or are at a high dose Features of an epidural that make it high risk for POUR include site of insertion (lumbar higher risk than thoracic), using long-acting local anaesthetic, hydrophilic or mu-receptor selective opioids, or using epidural adrenaline Post-operatively, risk of POUR is increased by having a bladder volume of >270 mL on arrival in the recovery room, receiving sedative medication (e.g midazolam) or receiving analgesia via continuous epidural infusion or a patient-controlled epidural device The previous history of bradycardia would increase the patient’s likelihood of POUR by increasing the likelihood of administration of prophylactic or therapeutic anti-muscarinic drugs Reference Baldini G, Bagry H, Aprikian A, Carli F Postoperative urinary retention: anesthetic and perioperative considerations Anesthesiology 2009; 110(5): 1139–57 Question 299: Non-heart beating organ donation A patient has been accepted for non-heart beating organ donation (NHBD) Which of the following organs cannot be successfully transplanted if the patient dies 90 minutes after withdrawal of active treatment? a) b) c) d) e) Heart valves Corneas Liver Skin Kidneys Answer: c Explanation Non-heart beating organ donation (NHBD) is not new, as the first cadaveric organs to be transplanted were retrieved as NHBDs Initially considered as marginal donors, improved techniques of organ preservation and assessment of function before transplantation have resulted in outcomes (certainly in the case of kidney transplants) to rival those achieved after transplantation of organs from heart beating donors Recently the number of organs that can be used following NHBD increased with reports of successful liver, pancreas and lung transplantations Currently, for liver transplantation to occur, the donor must die within an hour of withdrawal of treatment (two hours for renal transplantation) The decision to abandon organ donation is determined by the need to limit the warm ischaemic time and by the availability of an operating theatre and retrieval team Tissues that can be donated include corneas and sclera, heart valves, bone, tendons, menisci and skin Tissue can be retrieved up to 24 hours after circulatory arrest except for heart valves, which can be retrieved up to 48 hours after circulatory arrest Reference 290 Intensive Care Society Guidelines for adult organ and tissue donation Online at www ics.ac.uk/icmprof/downloads/Organ%20&%20Tissue%20Donation.pdf (Accessed December 2009) A 67-year-old, 75 kg woman requires anaesthesia for a total knee replacement Her admission blood results are reviewed Some of them are as follows: urea 15.1 mmol/L; creatinine 77 micromol/L; haemoglobin g/dL Which of the following represents the LEAST likely cause? Paper D Question 300: Urea: creatinine ratio a) Regular non-steroidal use over the past six months b) Chronic renal failure secondary to hypertension and non-insulin dependent diabetes mellitus c) That she is on medication for treatment of cardiac failure d) That she has been taking prednisolone, 20 mg daily, for the last six months e) A history of alcohol excess, known hepatic cirrhosis and oesophageal varices on endoscopy Answer: b Explanation A number of clinical situations may cause an elevated urea:creatinine ratio (UCR) These include dehydration, cardiac failure, diuretic therapy (hence Option (c) is true), gastrointestinal haemorrhage and high protein intake Steroid therapy and other causes of increased protein catabolism (e.g SIRS and sepsis) may also increase the UCR Conversely a low UCR is caused by a low protein diet, pregnancy, liver failure or overzealous hydration In chronic renal impairment and established acute renal failure the urea and creatinine should rise in parallel The other part to this question is the low haemoglobin (Hb) Insidious gastrointestinal bleeding can elevate the UCR and direct questioning should elicit evidence of change in stool colour A history of alcohol excess, known hepatic cirrhosis and oesophageal varices could result in either a high or a low UCR depending on the cause of the low Hb as it could be nutritionally related or due to gastrointestinal haemorrhage 291 Index 292 abbreviated mental test, 80, 281 abdominal emergency, 51, 201–2 ABO incompatibility, 17, 109–10 abscess, following gastric contents aspiration, 83, 289 acid–base management, cardiopulmonary bypass, 82, 286–7 acid–base physiology hyperchloraemic acidoses, 18, 113 lactic acidosis, 17, 48, 111–12, 192–3 acromegaly, 30–1, 145–6 acute coronary syndrome, 80, 279–80 acute liver failure, 25–6, 42, 134, 177 acute normovolaemic haemodilution (ANH), 57, 218–19 acute phase proteins, 14, 102 acute renal failure, 60, 226 contrast nephropathy, 25, 131–2 renal replacement therapy, 49, 195 acute tubular necrosis, 60, 226 adrenal cortex, 33, 154 AIDS-defining conditions, 58, 220 air embolism, 56, 215–16, 256–7 airway assessment, 24, 129–30, 185, 212 airway obstruction, 57, 217 albumin, 11, 93 alcohol withdrawal, 52, 203–4 allodynia, 70, 253–4 altitude anaesthesia, 41, 175–6 amethocaine gel (Ametop), 59, 223–4 amiodarone, 60, 225 amniotic fluid embolism (AFE), 33, 153 amputation, phantom limb pain (PLP), 51, 200–1 amylase, 33, 153–4 anabolic steroid abuse, 36, 161 anaemia macrocytic, 65, 238–9 preoperative, 30, 144–5 sickle cell, 202 anaesthetic breathing systems, 54, 208 anaesthetic cost, 53, 207 anaphylaxis, under anaesthesia, 25, 132 cause, 42, 178 signs, 25, 54, 132, 208–9 anion gap, 17, 111–12 ankle block, 43, 181 ankylosing spondylitis, 69–70, 251 anorexia nervosa, 22, 124–5 anticoagulants, 77, 271–2 epidural removal and, 50–1, 200 antiemetics, 20, 119–20 antihypertensives, side effects, 20, 119 antimicrobials, 18–19, 115 aortic regurgitation (AR), 80–1, 282 APACHE II, 22, 125 Apgar score, 63, 233–4 aprotinin, 37, 164–5 ASA score, 55, 211–12 aspiration, 69, 249–50 abscess following, 83, 289 aspirin overdose, 82, 287–8 asthma acute severe, 60–1, 67, 227, 244–5 brittle, 67, 244–5 in pregnancy, 17, 40, 111, 173 atlantoaxial instability, 60, 224 autologous blood transfusion, 57, 218–19 autonomic dysreflexia (AD), 81–2, 284–5 autonomic neuropathy, 24, 129 autosomal dominant polycystic kidney disease (ADPKD), 47, 190–1 awake tracheal intubation, 48, 193–4 awareness under anaesthesia, 68, 247–8 back pain, chronic, 63, 234 Bell’s phenomenon, 75, 266 beta blockers, 41, 174 beta-thalassaemia, 30, 144–5 biopotential measurement, 43–4, 181–2 calcium channel blockers, 46, 188 capacity for consent, 44–5, 184–5 capnography, 56, 216–17 carbohydrate-rich beverages, 38, 168 carbon dioxide detection, 38, 167 transport, 64, 236 carbon monoxide poisoning, 56, 215 carcinoid, 17, 110–11 cardiac arrest prognosis, 36, 162–3 cardiac output distribution, 34, 155 cardiac pacing, 59, 222 cardiac risk index, 55–6, 72, 213–14, 257–8 cardiac silhouette, 78, 274–5 cardiac tamponade, 22–3, 126 cardiopulmonary bypass, acid–base management, 82, 286–7 cardiotocograph foetal distress, 16–17, 109 cardiovascular reflexes, 21, 122–3 carotid endarterectomy, 81, 284 causalgia, 70, 253–4 central neuraxial blocks (CNB), 11–12, 95 central venous catheter (CVC), 74, 263–4 cerebrospinal fluid (CSF), 54, 70, 210, 251–2 Guillain–Barré syndrome and, 62, 230–1 values, 70, 251–2 chest drainage intercostal, 60, 225 negative pressure, 14, 101–2 Child–Pugh score, 42, 177–8 children See paediatrics chronic kidney disease, 50, 198 chronic renal failure, 76, 270 coagulopathy, 76, 270 cisapride, 37, 164–5 clonidine, 66, 241 Clostridium difficile, 27, 138 coagulopathy of chronic renal failure, 76, 270 cocaine, 11, 94–5 Moffett’s solution, 245–6 cognitive dysfunction, older patients, 80, 281 collapsing pulse, 80–1, 282 colloid preparations, 16, 107, 143 community-acquired pneumonia, 71, 254–5 complex regional pain syndrome, 72, 258–9 Conn’s syndrome, 37, 165–6 consent capacity, 44–5, 184–5 continuous venovenous haemodiafiltration (CVVHDF), 49, 195 contrast-induced nephropathy (CIN), 25, 131–2 co-proxamol, 37, 164–5 coronary artery blood flow, 26, 134–5 coroner, referral to, 50, 199 cost per hour, 53, 207 Crack cocaine, 11, 94–5 cranial nerve examination for brainstem death, 27–8, 139–40 C-reactive protein (CRP), 14, 102 Creutzfeldt–Jacob disease (CJD), 68, 248–9 critical care, harmful drugs, 81, 283–4 croup, 23, 126–7 CURB65 score, 71, 254–5 cyanosis, 64, 236–7 cyclophosphamide, 32, 150 Index blood gas analysis hydrogen ion measurement, 21, 121 oxygenation indices, 26, 135–6 spectrophotometric oximetry, 35, 159–60 toxicology, 31, 146 blood pressure invasive arterial monitoring, 44, 183–4 measurement, 16, 107–8 blood sample collection, 13, 99–0, 99 blood transfusion autologous, 57, 218–19 hazards, 36, 162 immunology, 17, 109–10 bodybuilding, 36, 161 Boerhaave syndrome, 54–5, 210–11 botulinum toxin, 57, 217–18 Bowman effect, 21, 122–3 brachial plexus, 26, 135 blocking, 41, 174–5 brainstem death, 27–8, 139–40 breastfeeding, 75, 266–7 breathing systems, 54, 208 brittle asthma, 67, 244–5 burns, fluid replacement, 23, 128 dabigatran, 37, 165 day surgery spinal, 223 discharge, 187 death, 27–8, 139–40 referral to coroner, 50, 199 delirium, 66, 241–2 dental procedures in children, 77, 273 diabetes mellitus, 37, 163–4 diarrhoea Clostridium difficile infection, 27, 138 digital clubbing, 58, 219–20 disseminated intravascular coagulation (DIC), 29, 142 dose–response curves, 63–4, 235–6 Down’s syndrome, 76, 268 droperidol, 37, 164–5 drowning, 36, 160–1 drug adverse effects, 37, 164–5 anaphylaxis under anaesthesia, 42, 178 antihypertensives, 20, 119 local anaesthetic toxicity, 45, 186–7 suxamethonium, 71, 256, 269–70 drug avoidance, 27, 137 drug infusion rate, 16, 108 drug overdose, 82, 287–8 drugs, morning before surgery, 70–1, 254 duodenal ulcer, 26, 136 ear, nose and throat (ENT) surgery, 53, 206, 245–6 ectopic pregnancy blood transfusion, 17, 109–10 elective neurosurgery, 33, 151–2 electrical equipment safety, 15, 105–6 electrocardiography (ECG) intraoperative monitoring, 78–9, 275–6 limb lead displacement, 19, 115 prolonged QT interval, 58–9, 62, 221, 232 U wave causes, 38, 168–9 EMLA, 59, 223–4 epicardial pacing wires, 59, 222 epidural removal, anticoagulant and, 50–1, 200 erythrocyte sedimentation rate (ESR), 14, 102 293 Index estimated glomerular filtration rate (eGFR), 31–2, 148 etomidate, 33, 154 extended matching questions (EMQs), 3–4 femoral neck fractures, 35, 159 fentanyl, 23, 128 FLACC scale, 18, 113–14 fluid management following burns, 23, 128 intravenous fluid administration, 68, 247 intravenous fluid content, 78, 275 paediatric, 72–3, 259 peri-operative, 29–30, 143 foetal distress, 16–17, 109 fondaparinux, 77, 271–2 food allergies drug avoidance, 27, 137 foot, regional anaesthesia, 43, 181 fracture, femoral neck, 35, 159 gadolinium, 23, 127 gas analysis, 38, 167 See also blood gas analysis paramagnetism, 41, 175 gas embolism, 71–2, 215–16, 256–7 gastric contents aspiration, 69, 249–50 abscess following, 83, 289 Glasgow Coma Score (GCS), 22, 125 glomerular filtration rate calculation, 31–2, 148 Gram stain, 69, 249 Guillain–Barré syndrome (GBS), 62, 230–1 294 haemodynamic monitoring, 53, 206–7, 219 haemophilia, 46, 188–9 Haldane effect, 64, 236 handwashing, 52, 204 hangover, 77, 272–3 haptoglobin, 14, 102 HbH disease, 30, 144–5 head injury postoperative complications, 14, 103–4 heart disease See also cardiac risk index enlarged cardiac silhouette, 78, 274–5 recurrent myocardial ischaemia risk, 80, 279–80 valvular, 25, 106–7, 133–4, 282 heart murmur, 15, 106–7 heat loss, 18, 114–15 heat moisture exchange filter, 20, 120 heparin, 77, 271–2 heparin-induced thrombocytopenia (HIT), 38, 167–8 hepatitis B, 44, 182–3 herbal remedies warfarin therapy and, 40–1, 173–4 Hetastarch solution, 29–30, 143 high-frequency oscillatory ventilation (HFOV), 31, 147–8 hydrogen electrode, 61, 229 hydrogen ion measurement, 21, 121 hyperalgesia, 70, 253–4 hyperchloraemic acidosis, 18, 113 0.9% saline solution and, 68, 247 hyperpathia, 70, 253–4 hypertrophic pyloric stenosis (HPS), 72, 257 hypoalbuminaemia, 11, 93 hyponatraemia, 55, 74, 213, 262–3 hypothermia, 73–4, 261–2 implantable cardiac defibrillators, 28, 140 infective endocarditis prophylaxis, 12, 96–7 inotropic drugs, 33, 152–3 infusion rate, 16, 108 levosimendan, 79, 277–8 intensive care unit (ICU) acquired weaknesses, 34, 156–7 intercostal chest drainage, 60, 225 intraocular pressure, 19, 115 intraoperative cell salvage (ICS), 79, 218–19, 276–7 intratracheal drug administration, 81, 283 intravenous fluid administration, 68, 247 children, 72–3, 259 intubation awake tracheal intubation, 48, 193–4 failure, 37–8, 166 morbidly obese patients, 55, 212 paediatric advanced life support, 39–40, 171–2 ischaemic colitis, 51, 201–2 ischaemic optic neuropathy, 51–2, 202 isoflurane administration, 25, 132–3 Jehovah’s Witness, 42–3, 179, 218 ketamine, 24, 130–1 kidney disease, 50, 198, See also renal failure Korotkoff sounds, 16, 107–8 kurtosis, 76, 268–9 lactate metabolism, 48, 192–3 lactic acidosis, 48, 192–3 normal anion gap, 17, 111–12 Lambert–Eaton myasthenic syndrome, 39, 170 laryngeal muscles, 21–2, 123–4 latex allergy, 74, 263 laws of physics, 47, 190 left ventricular preload, 53, 206–7 levobupivacaine, 63, 234–5 levosimendan, 79, 277–8 liver disease, 42, 177–8 acute liver failure, 25–6, 42, 134, 177 Child–Pugh score, 42, 177–8 local anaesthetics, 63, 234–5 eutectic mixture, 59, 223–4 systemic absorption, 59, 221–2 toxicity, 45, 186–7 low molecular weight heparins (LMWH), 77, 271–2 lumbar plexus, 42, 178 lung non-respiratory functions, 20, 118–19 one-lung ventilation, 80, 281, 282 residual volume, 16, 108–9 macrocytic anaemia, 65, 238–9 malaria, severe infection with, 79, 278 malignant carcinoid syndrome, 17, 110–11 malignant hyperthermia, 68, 246–7 Marfan’s syndrome, 62–3, 232–3 maternal death, 27, 138–9 MELD score (Model for End-stage Liver Disease), 42, 177–8 mental capacity for consent, 44–5, 184–5 meta-analysis, 0–101 metabolic stress response, 64, 237–8 methylene blue, 40, 172 nabilone, 20, 119–20 narrow-complex tachycardia, 20–1, 120–1 nasal surgery, 67–8, 245–6 nasogastric tube positioning, 12, 95–6 natural rubber latex (NRL), allergy, 74, 263 nausea and vomiting, postoperative, 52–3, 204–5 necrotising fasciitis, 48–9, 194–5 needle stick injury, 44, 182–3 neonatal physiology, 82, 285 neuralgia, 70, 253–4 trigeminal, 70, 252 neuraxial blocks, 11–12, 95 neuromuscular blockade monitoring, 66, 240–1 neurophysiological monitoring, 19, 117–18 neurophysiology, 54, 210 non-depolarising muscle relaxants (NDMR), 49–50, 197–8 non-heart beating organ donation (NHBD), 83, 290 non-invasive ventilation, 39, 169–70 noradrenaline, 81, 283–4 number needed to treat (NNT), 17–18, 112–13 obesity, intubation and, 55, 212 obstetric anaesthesia, 61–2, 229–30 obstetric emergencies, 33, 153 obstetric mortality, 27, 138–9 obstructive sleep apnoea, 48, 193 oesophageal Doppler probe, 73, 261 oesophageal rupture, 54–5, 210–11 opioids, 23, 128 pharmacokinetics, 54, 209–10 organ donation, 83, 290 organophosphate poisoning, 31, 146 osmolality, 82, 286 oximetry, 35, 159–60 oxycodone, 75, 266–7 oxygen requirements, 75, 267–8 oxygenation indices, 26, 135–6 paediatrics acute stridor, 23, 126–7 advanced life support, 39–40, 171–2 dental procedures, 77, 273 eutectic mixture of local anaesthetics, 59, 223–4 intravenous infusion administration, 72–3, 259 postoperative pain, 18, 113–14 surgical conditions, 73, 259–60 pain chronic back pain, 63, 234 complex regional pain syndrome, 72, 258–9 definitions, 70, 253–4 paediatric postoperative pain, 18, 113–14 phantom limb pain (PLP), 51, 200–1 pancreatitis, 73, 260–1 paramagnetic gases, 41, 175 Parkland formula, 23, 128 patient positioning, 67, 243 patient-reported outcome measures (PROMs), 56, 214 patient transfer oxygen requirements, 75, 267–8 Pentastarch solution, 29–30, 143 peptic ulcer disease, 26, 136 peri-arrest arrhythmia, 78, 274 peri-operative care fluid management, 29–30, 143 porphyria and, 43, 179–80 risk management, 24, 130 peri-operative loss of vision, 51–2, 202 phantom limb pain (PLP), 51, 200–1 pharmacodynamics, 63–4, 235–6 phenylephrine, 29, 141 placenta removal, 56, 215 pneumonia community-acquired, 71, 254–5 right pneumonic consolidation, 0, 13 ventilator-associated, 53, 205–6 poisoning antidepressants, 12, 98 blood gas analysis, 31, 146 carbon monoxide, 56, 215 drug overdose, 82, 287–8 organophosphates, 31, 146 polycystic kidney disease, 47, 190–1 porphyria, 32, 43, 150–1, 179–80 postoperative cognitive deficit (POCD), 80, 281 postoperative complications, 56, 215 nausea and vomiting (PONV), 52–3, 204–5 paediatric postoperative pain, 18, 113–14 prevention, 24, 130 retained placenta removal, 56 trauma surgery, 14, 103–4 urinary retention, 83, 289–90 postural cardiovascular homeostasis, 77, 270–1 P-POSSUM score, 80, 280 pre-eclampsia risk factors, 52, 203 pregnancy See also ectopic pregnancy asthma in, 17, 40, 111, 173 non-obstetric surgery, 34–5, 157–8 physiological changes, 18, 114 Index microlaryngoscopy, 24, 129–30 minimum alveolar concentration (MAC), 71, 255 mitral stenosis, 25, 133–4 mixed venous oxygen saturations, 21, 123 moclobemide, 14–15, 104–5 Moffett’s solution, 67–8, 245–6 monitoring haemodynamic, 53, 206–7, 219 intraoperative ECG monitoring, 78–9, 275–6 invasive arterial blood pressure monitoring, 44, 183–4 neuromuscular blockade, 66, 240–1 neurophysiological, 19, 117–18 recommendations, 58, 220–1 spinal cord, 30, 144 monoamine oxidase inhibitors, 14–15, 104–5 Monro–Kellie doctrine, 54, 210 morning drugs, 70–1, 254 morphine, 23, 54, 128, 209–10 MTF questions, 2–2, multiple sclerosis relapse, 34, 157 muscle relaxants, 49–50, 197–8 strabismus surgery, 75, 266 myasthenia gravis, 75, 265–6 crisis management, 12, 97–8 distinction from Lambert–Eaton myasthenic syndrome, 39, 170 myocardial ischaemia, recurrence risk, 80, 279–80 295 Index preoperative autologous donation (PAD), 57, 218–19 pre-renal uraemia, 60, 226, 291 primary hyperaldosteronism, 37, 165–6 procalcitonin (PCT), 70, 252–3 prone positioning, 67, 243 prostaglandins in pregnancy, 40, 173 pseudocholinesterase deficiency, 76, 269–70 pulmonary artery flotation catheters, 61, 228–9 pulmonary embolism, 15, 105 pulmonary oedema, 32, 149 pulmonary vasoconstriction, 11, 94–5 pulse, collapsing, 80–1, 282 pyloric stenosis, 18, 72, 73, 113, 257, 259–60 QT interval, prolonged, 58–9, 62, 221, 232 refeeding syndrome, 29, 141–2 renal failure acute, 49, 60, 195, 226, 291 chronic, 76, 270 renal replacement therapy, 49, 195 residual volume measurement, 16, 108–9 respiratory failure, 0, 13 retained placenta removal, 56, 215–16 retroperitoneal haemorrhage, 14, 102–3 revised cardiac risk index, 55–6, 72, 213–14, 257–8 revision, 7–8 rhabdomyolysis, 74, 264–5 rhesus D incompatibility, 17, 109–10 rheumatoid factor, 14, 102 rivaroxaban, 37, 165 rofecoxib, 37, 164–5 salicylate overdose, 82, 287–8 saline solution administration, 68, 247 sedation, 48, 193–4 sepsis, 45, 185–6 Gram stain, 69, 249 Serious Hazards of Transfusion (SHOT) reports , 36, 162 SI units, 46, 187 skewness, 76, 268–9 sleep apnoea, 48, 193 smoking, 47–8, 191–2 smoking cessation, 24, 30, 130, 143–4 soda lime, 39, 171 sodium nitroprusside, 44, 183 somatosensory evoked potentials, 30, 144 spectrophotometric oximetry, 35, 159–60 spinal anaesthesia, day case unit, 59, 223 spinal cord arterial supply, 40, 172–3 monitoring, 30, 144 spinal trauma management, 64–5, 238 splenectomy, follow-up care, 83, 288–9 standard error of the mean (SEM), 79, 278–9 statistical analysis, 34, 155–6 strabismus surgery, 75, 266 stress response, 64, 237–8 stridor, 23, 126–7 subarachnoid anaesthesia, day case unit, 59, 223 subarachnoid haemorrhage, 49, 196 sugammadex, 11, 94 296 supine hypotensive syndrome, 230 suxamethonium, unwanted effects, 71, 256, 269–70 syncope, 61–2, 229–30 syndrome of inappropriate antidiuretic hormone secretion, 55, 213 systemic lupus erythematosus (SLE), 31, 146–7 systemic vascular resistance (SVR), 58, 219 tachycardia, narrow-complex, 20–1, 120–1 teeth, 45, 185 temperature measurement, 43, 180–1 tetanus, 51, 201 thiocyanate, 44, 183 thiopentone, 62, 231–2 throat pack safety, 39, 169 thrombocytopaenia, 19, 117 heparin-induced (HIT), 38, 167–8 thromboelastography, 19, 117 tissue donation contraindications, 21, 121–2 torniquets, 13, 98–9 total body plethysmography, 16, 108–9 total intravenous anaesthesia, 61, 227–8 toxicology, blood gases, 31, 146 tracheal anatomy, 49, 196–7 tracheostomy, 49, 196–7 problem management, 69, 250–1 transfusion See blood transfusion trauma management, 64–5, 238 tricyclic antidepressant drugs overdose, 12, 98 trigeminal neuralgia, 70, 252 troponin, 67, 242–3 U wave causes, 38, 168–9 ultrasound, 35, 158–9 urea/creatinine ratio, 83–4, 291 urinalysis, 26–7, 136–7, 263–4 urinary retention, postoperative, 83, 289–90 uterine tone, 61, 228 Valsalva manoeuvre, 50, 198–9 valvular heart disease, 25, 133–4 vaporiser setting, 25, 132–3 ventilation high-frequency oscillatory ventilation, 31, 147–8 non-invasive, 39, 169–70 one-lung ventilation, 80, 281, 282 oxygen requirements, 75, 267–8 ventilator-associated pneumonia, 53, 205–6 ventilators in the operating theatre, 42, 176–7 vision loss, peri-operative, 51–2, 202 volatile anaesthesia, 71, 255 warfarin therapy, 14, 102 drug interactions, 14, 102–3 herbal remedy effects, 40–1, 173–4 water hammer pulse, 80–1, 282 Wegener’s granulomatosis, 32, 150 WHO Surgical Safety Checklist, 67, 245 withdrawn drugs, 37, 164–5 xenon, 32, 149–50 ...This page intentionally left blank SBAs for the Final FRCA SBAs for the Final FRCA Dr James Nickells FRCA Dr Tobias Everett FRCA Dr Benjamin Walton FRCA North Bristol NHS Trust Bristol CAMBRIDGE... the SBA questions in the Final FRCA MCQ exam ix SBA FAQs The Final FRCA: what is the point? What are SBAs? What does the MCQ paper consist of? How many marks will I get for a correct SBA question?... elsewhere For a number of years we have been teaching and lecturing on MCQs for the Final FRCA Up to 2008, this included an hour-long lecture on our Crammer Course on good tactics for answering