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Multiple Choice Answers
Multiple Choice Answers 43. A patient reports gentle stroking with cotton wool to be extremely painful.This reliably indicates:
48. The following drugs are oral treatments which can be used as single agents to treat Parkinson’s disease:
(a) False; (b) False; (c) False; (d) True; (e) False (d) Dynamic allodynia is evoked by a moving touch stimulus. In this case, the brushing with cotton wool is perceived by the patient as being painful. (a) Paraesthesia is never painful. (b) There is no strong evidence to link symptoms such as dynamic allodynia to specific treatments.
(a) True; (b) True; (c) True; (d) False; (e) False (a–c) Levodopa, bromocriptine and selegiline are all recognised monotherapy agents for PD and are administered orally. (d) Apomorphine can be used as monotherapy in the perioperative period but is given by the subcutaneous route. (e) Entacapone is a catechol-O-methyl inhibitor which is only used in conjunction with a levodopa-DDI combination.
44. In selecting a treatment for neuropathic pain: (a) False; (b) False; (c) False; (d) True; (e) False There is little evidence to guide which treatment will work most effectively for a particular patient. Hence the history and examination (a,c) do not reliably indicate which treatment should be chosen and hence the selection is often empirical. 45. Which of the following are associated with neuropathic pains: (a) False; (b) True; (c) True; (d) False; (e) True (a,d) Neither migraine or temporal arteritis result from CNS lesions hence they are not neuropathic pains. 46. In complex regional pain syndrome type I, typically the affected limb may be: (a) True; (b) True; (c) True; (d) True; (e) True CRPS type I may present with any of the above signs. Indeed, a limb may progress from hot, swollen and sweaty to cold, scaly, calloused, dry and atrophied over a period months.
47. The following are recognised features of Parkinson’s disease: (a) True; (b) True; (c) False; (d) True; (e) False (a) Tremor is a cardinal feature of Parkinson’s disease (PD). (b) Orthostatic hypotension may caused by PD or by dopaminergic or anticholinergic agents. (c) PD leads to salivary pooling and sialorrhoea in up to 70% of patients. Anticholinergic agents may cause a dry mouth. (d) A restrictive ventilatory defect reflects rigidity in the respiratory muscles. (e) PD can cause voiding difficulties as a consequence of dysautonomia but intrinsic renal disease is not a feature.
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49. Movement disorders may be precipitated by: (a) True; (b) True; (c) True; (d) True; (e) True All of these agents have been implicated in movement disorders. Alfentanil can cause muscle rigidity and has been implicated in unmasking PD in a case report. Prochlorperazine has dopamine antagonizing effects. Levodopa in excessive doses causes peak-dose dyskinesias. 50. With respect to long-term complications after cardiac transplantation: (a) True; (b) True; (c) True; (d) True; (e) True (a) Endomyocardial biopsy remains the definitive investigation. (b) Particularly squamous cell carcinoma of the skin and lymphoma. (c) A proportion resolve with high dose acyclovir therapy. (d) Cyclosporin causes chronic renal failure. (e) Hypertension is common and is, in part, related to cyclosporin therapy. 51. With respect to immunosuppressive therapy and infection after cardiac transplantation: (a) False; (b) False; (c) False; (d) True; (e) True (a) Cyclosporin is not myelotoxic. (b) Azathioprine is available i.v., but is highly irritant and rarely used. (c) The bioavailability of oral cyclosporin is ~30%. (d,e) Primary CMV infection can result in a pronounced symptomatic illness in transplant recipients. Patients who are seronegative for CMV should not be given blood from CMV-positive donors. 52. After cardiac transplantation: (a) False; (b) False; (c) False; (d) False; (e) True (a) In practice, rarely seen on the surface ECG. (b) RBBB occurs in 10% of patients after transplantation. (c) Resting heart rate is 90–100 bpm due to the loss of normal vagal
British Journal of Anaesthesia | CEPD Reviews | Volume 2 Number 3 2002
Multiple choice answers
tone. (d) Digoxin’s anti-arrhythmic effect is dependent upon an intact vagus. (e) The heart is denervated; however, angina can occur following sympathetic re-innervation. 53. When considering anaesthesia in a patient with a heart transplant: (a) True; (b) False; (c) False; (d) False; (e) True (a) Oral tracheal intubation is preferred to prevent dissemination of nasal flora. (b) Cardiac vagolytic effects of atropine is lost. (c) No contra-indication, but strict aseptic technique is essential. (d) Cardiac biopsies are performed via the right internal jugular vein and this site is best avoided. (e) Lack of rapid homeostatic adjustments in heart rate can produce wide swings in blood pressure.
for continuous infusions. (c) Use of protocols and supervision by an APS increases safety by allowing all staff to be familiar with regimens being used. (d,e) Poor patient selection is a more common cause of problems than equipment failure. 58. Patient factors more likely to be associated with the successful use of PCA include: (a) True; (b) True; (c) False; (d) False; (e) False (a,b) Patients using PCA need to understand the principles involved and be able to trigger the device. (c,d) With careful patient selection and supervision by an APS, PCA can be used safely at the extremes of age. (e) Adequate analgesia can be difficult to achieve with PCA in certain clinical situations, e.g. elderly patients having upper abdominal surgery due to a narrow therapeutic index.
54. The aim of PCA is to: (a) False; (b) True; (c) False; (d) False; (e) True (a,e) The aim of PCA is to allow the patient to keep their plasma opioid concentrations above MEAC but below MTC, despite MEAC varying with time. (b,c) Increased independence is an advantage of the technique but should not result in reduced levels of nursing contact. (d) There is no evidence that use of PCA improves postoperative outcome. 55. An electronic PCA device should: (a) False; (b) True; (c) True; (d) True; (e) True (a) An easily identifiable PCA pump improves safety. (b–d,) All electronic PCA devices should have an occlusion and air-inthe-line alarm, flexible programming and a lock to prevent tampering. (e) Both anti-syphon and anti-reflux valves are necessary. 56. A PCA regimen should always include: (a) True; (b) False; (c) False; (d) False; (e) True (a) Sub-analgesic bolus doses may lead to abandonment of the technique. (b) Use of a background infusion more than doubles the incidence of respiratory depression without improving analgesia. (c) With morphine, a lockout interval of 5–10 min is used, despite a peak effect occurring at 15 min. (d,e) Risk reduction can be achieved by standardisation of the drug used and postoperative care. 57. With regards to the safety of PCA: (a) False; (b) True; (c) True; (d) False; (e) True (a,b) Incidence of respiratory depression with PCA is 0.1–0.8% compared with 0.2–0.9% for intramuscular regimens and 1.7%
59. Absolute indications for a double lumen tube are: (a) True; (b) False; (c) True; (d) True; (e) False (a,c,d) All are absolute indications for a double lumen tube. Ventilation using a conventional endotracheal tube results in substantial loss of tidal volume through the bronchopleural fistula. Avoiding the ventilation of a unilateral cyst prevents overdistension and barotrauma. Isolation of the infected lung prevents contamination of normal lung. (b,e) Surgical access is a desirable, but not essential, indication. 60. With regard to hypoxic pulmonary vasoconstriction (HPV): (a) True; (b) False; (c) False; (d) False; (e) True (a) Alveolar hypoxia is the biggest stimulus for HPV. (b,c) Isoflurane 1 MAC and nitrous oxide inhibit HPV by 20% and 10%, respectively. (d) Propofol has little effect on HPV. (e) High pulmonary artery pressure results in increased blood flow to both lungs so HPV is reduced in the non-ventilated lung. 61. During one-lung anaesthesia: (a) False; (b) True; (c) False; (d) False; (e) True (a) A left thoracotomy does not necessitate a right-sided double-lumen tube unless for isolation or for control of distribution of ventilation. (b) The diameter of a bronchial blocker lends itself to paediatric use. (c,e) End-tidal CO2 is relatively well-maintained with a tidal volume of 8–15 ml kg–1 and oxygenation is improved with CPAP to the non-ventilated lung. (d) Hypotension increases the V/Q mismatch and is not recommended.
British Journal of Anaesthesia | CEPD Reviews | Volume 2 Number 3 2002
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Multiple choice answers
62. Myasthenia gravis: (a) False; (b) True; (c) True; (d) True; (e) False (a,b) Myasthenia gravis affects 1 in 10,000 of the population and is often a disease of young women and older men. (c,d) It affects the eyes in more than 90% of patients and respiratory muscle weakness can result in respiratory failure. (e) It only affects the motor system. 63. Myasthenia gravis can be diagnosed with certainty by: (a) False; (b) False; (c) False; (d) False; (e) True The only definite method of diagnosing myasthenia gravis is by detection of anti-AchR antibodies.All other tests may be highly suggestive of a neuromuscular defect but are not specific. 64. The following are used in the long-term therapy of myasthenia gravis: (a) False; (b) True; (c) False; (d) False; (e) True (b,e) Anticholinesterases with a long half-life such as pyridostigmine and corticosteroids such as prednisolone are the mainstay of treatment for myasthenia gravis. (a) Edrophonium is a short-acting anticholinesterase used in the diagnosis of myasthenia. (c,d) Both plasma exchange and intravenous
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immunoglobulin are used in producing a short-term improvement of myasthenic weakness. 65. Concerning the effects of drugs in myasthenia gravis: (a) False; (b) True; (c) False; (d) True; (e) True (a) There is an exaggerated response to the neuromuscular blocking effects of volatile anaesthetic agents. (b) Although resistance to succinylcholine is common, there may be a normal response. (c) Patients require 30–40% of the normal dose of atracurium. (d,e) Aminoglycosides worsen neuromuscular blockade and there may be deterioration in muscle power on starting corticosteroids. 66. The following variables are predictors of the need for prolonged postoperative ventilation: (a) False; (b) False; (c) True; (d) False; (e) True Positive predictors of need for prolonged postoperative ventilation include a forced vital capacity < 2.9 litres, a long history of myasthenia gravis, co-existing pulmonary disease and severe (grades III and IV) myasthenia.Trans-sternal thymectomy rather than transcervical thymectomy often requires postoperative ventilation.
British Journal of Anaesthesia | CEPD Reviews | Volume 2 Number 3 2002
48. The following drugs are oral treatments which can be used as single agents to treat Parkinson’s disease:
(a) False; (b) False; (c) False; (d) True; (e) False (d) Dynamic allodynia is evoked by a moving touch stimulus. In this case, the brushing with cotton wool is perceived by the patient as being painful. (a) Paraesthesia is never painful. (b) There is no strong evidence to link symptoms such as dynamic allodynia to specific treatments.
(a) True; (b) True; (c) True; (d) False; (e) False (a–c) Levodopa, bromocriptine and selegiline are all recognised monotherapy agents for PD and are administered orally. (d) Apomorphine can be used as monotherapy in the perioperative period but is given by the subcutaneous route. (e) Entacapone is a catechol-O-methyl inhibitor which is only used in conjunction with a levodopa-DDI combination.
44. In selecting a treatment for neuropathic pain: (a) False; (b) False; (c) False; (d) True; (e) False There is little evidence to guide which treatment will work most effectively for a particular patient. Hence the history and examination (a,c) do not reliably indicate which treatment should be chosen and hence the selection is often empirical. 45. Which of the following are associated with neuropathic pains: (a) False; (b) True; (c) True; (d) False; (e) True (a,d) Neither migraine or temporal arteritis result from CNS lesions hence they are not neuropathic pains. 46. In complex regional pain syndrome type I, typically the affected limb may be: (a) True; (b) True; (c) True; (d) True; (e) True CRPS type I may present with any of the above signs. Indeed, a limb may progress from hot, swollen and sweaty to cold, scaly, calloused, dry and atrophied over a period months.
47. The following are recognised features of Parkinson’s disease: (a) True; (b) True; (c) False; (d) True; (e) False (a) Tremor is a cardinal feature of Parkinson’s disease (PD). (b) Orthostatic hypotension may caused by PD or by dopaminergic or anticholinergic agents. (c) PD leads to salivary pooling and sialorrhoea in up to 70% of patients. Anticholinergic agents may cause a dry mouth. (d) A restrictive ventilatory defect reflects rigidity in the respiratory muscles. (e) PD can cause voiding difficulties as a consequence of dysautonomia but intrinsic renal disease is not a feature.
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49. Movement disorders may be precipitated by: (a) True; (b) True; (c) True; (d) True; (e) True All of these agents have been implicated in movement disorders. Alfentanil can cause muscle rigidity and has been implicated in unmasking PD in a case report. Prochlorperazine has dopamine antagonizing effects. Levodopa in excessive doses causes peak-dose dyskinesias. 50. With respect to long-term complications after cardiac transplantation: (a) True; (b) True; (c) True; (d) True; (e) True (a) Endomyocardial biopsy remains the definitive investigation. (b) Particularly squamous cell carcinoma of the skin and lymphoma. (c) A proportion resolve with high dose acyclovir therapy. (d) Cyclosporin causes chronic renal failure. (e) Hypertension is common and is, in part, related to cyclosporin therapy. 51. With respect to immunosuppressive therapy and infection after cardiac transplantation: (a) False; (b) False; (c) False; (d) True; (e) True (a) Cyclosporin is not myelotoxic. (b) Azathioprine is available i.v., but is highly irritant and rarely used. (c) The bioavailability of oral cyclosporin is ~30%. (d,e) Primary CMV infection can result in a pronounced symptomatic illness in transplant recipients. Patients who are seronegative for CMV should not be given blood from CMV-positive donors. 52. After cardiac transplantation: (a) False; (b) False; (c) False; (d) False; (e) True (a) In practice, rarely seen on the surface ECG. (b) RBBB occurs in 10% of patients after transplantation. (c) Resting heart rate is 90–100 bpm due to the loss of normal vagal
British Journal of Anaesthesia | CEPD Reviews | Volume 2 Number 3 2002
Multiple choice answers
tone. (d) Digoxin’s anti-arrhythmic effect is dependent upon an intact vagus. (e) The heart is denervated; however, angina can occur following sympathetic re-innervation. 53. When considering anaesthesia in a patient with a heart transplant: (a) True; (b) False; (c) False; (d) False; (e) True (a) Oral tracheal intubation is preferred to prevent dissemination of nasal flora. (b) Cardiac vagolytic effects of atropine is lost. (c) No contra-indication, but strict aseptic technique is essential. (d) Cardiac biopsies are performed via the right internal jugular vein and this site is best avoided. (e) Lack of rapid homeostatic adjustments in heart rate can produce wide swings in blood pressure.
for continuous infusions. (c) Use of protocols and supervision by an APS increases safety by allowing all staff to be familiar with regimens being used. (d,e) Poor patient selection is a more common cause of problems than equipment failure. 58. Patient factors more likely to be associated with the successful use of PCA include: (a) True; (b) True; (c) False; (d) False; (e) False (a,b) Patients using PCA need to understand the principles involved and be able to trigger the device. (c,d) With careful patient selection and supervision by an APS, PCA can be used safely at the extremes of age. (e) Adequate analgesia can be difficult to achieve with PCA in certain clinical situations, e.g. elderly patients having upper abdominal surgery due to a narrow therapeutic index.
54. The aim of PCA is to: (a) False; (b) True; (c) False; (d) False; (e) True (a,e) The aim of PCA is to allow the patient to keep their plasma opioid concentrations above MEAC but below MTC, despite MEAC varying with time. (b,c) Increased independence is an advantage of the technique but should not result in reduced levels of nursing contact. (d) There is no evidence that use of PCA improves postoperative outcome. 55. An electronic PCA device should: (a) False; (b) True; (c) True; (d) True; (e) True (a) An easily identifiable PCA pump improves safety. (b–d,) All electronic PCA devices should have an occlusion and air-inthe-line alarm, flexible programming and a lock to prevent tampering. (e) Both anti-syphon and anti-reflux valves are necessary. 56. A PCA regimen should always include: (a) True; (b) False; (c) False; (d) False; (e) True (a) Sub-analgesic bolus doses may lead to abandonment of the technique. (b) Use of a background infusion more than doubles the incidence of respiratory depression without improving analgesia. (c) With morphine, a lockout interval of 5–10 min is used, despite a peak effect occurring at 15 min. (d,e) Risk reduction can be achieved by standardisation of the drug used and postoperative care. 57. With regards to the safety of PCA: (a) False; (b) True; (c) True; (d) False; (e) True (a,b) Incidence of respiratory depression with PCA is 0.1–0.8% compared with 0.2–0.9% for intramuscular regimens and 1.7%
59. Absolute indications for a double lumen tube are: (a) True; (b) False; (c) True; (d) True; (e) False (a,c,d) All are absolute indications for a double lumen tube. Ventilation using a conventional endotracheal tube results in substantial loss of tidal volume through the bronchopleural fistula. Avoiding the ventilation of a unilateral cyst prevents overdistension and barotrauma. Isolation of the infected lung prevents contamination of normal lung. (b,e) Surgical access is a desirable, but not essential, indication. 60. With regard to hypoxic pulmonary vasoconstriction (HPV): (a) True; (b) False; (c) False; (d) False; (e) True (a) Alveolar hypoxia is the biggest stimulus for HPV. (b,c) Isoflurane 1 MAC and nitrous oxide inhibit HPV by 20% and 10%, respectively. (d) Propofol has little effect on HPV. (e) High pulmonary artery pressure results in increased blood flow to both lungs so HPV is reduced in the non-ventilated lung. 61. During one-lung anaesthesia: (a) False; (b) True; (c) False; (d) False; (e) True (a) A left thoracotomy does not necessitate a right-sided double-lumen tube unless for isolation or for control of distribution of ventilation. (b) The diameter of a bronchial blocker lends itself to paediatric use. (c,e) End-tidal CO2 is relatively well-maintained with a tidal volume of 8–15 ml kg–1 and oxygenation is improved with CPAP to the non-ventilated lung. (d) Hypotension increases the V/Q mismatch and is not recommended.
British Journal of Anaesthesia | CEPD Reviews | Volume 2 Number 3 2002
95
Multiple choice answers
62. Myasthenia gravis: (a) False; (b) True; (c) True; (d) True; (e) False (a,b) Myasthenia gravis affects 1 in 10,000 of the population and is often a disease of young women and older men. (c,d) It affects the eyes in more than 90% of patients and respiratory muscle weakness can result in respiratory failure. (e) It only affects the motor system. 63. Myasthenia gravis can be diagnosed with certainty by: (a) False; (b) False; (c) False; (d) False; (e) True The only definite method of diagnosing myasthenia gravis is by detection of anti-AchR antibodies.All other tests may be highly suggestive of a neuromuscular defect but are not specific. 64. The following are used in the long-term therapy of myasthenia gravis: (a) False; (b) True; (c) False; (d) False; (e) True (b,e) Anticholinesterases with a long half-life such as pyridostigmine and corticosteroids such as prednisolone are the mainstay of treatment for myasthenia gravis. (a) Edrophonium is a short-acting anticholinesterase used in the diagnosis of myasthenia. (c,d) Both plasma exchange and intravenous
96
immunoglobulin are used in producing a short-term improvement of myasthenic weakness. 65. Concerning the effects of drugs in myasthenia gravis: (a) False; (b) True; (c) False; (d) True; (e) True (a) There is an exaggerated response to the neuromuscular blocking effects of volatile anaesthetic agents. (b) Although resistance to succinylcholine is common, there may be a normal response. (c) Patients require 30–40% of the normal dose of atracurium. (d,e) Aminoglycosides worsen neuromuscular blockade and there may be deterioration in muscle power on starting corticosteroids. 66. The following variables are predictors of the need for prolonged postoperative ventilation: (a) False; (b) False; (c) True; (d) False; (e) True Positive predictors of need for prolonged postoperative ventilation include a forced vital capacity < 2.9 litres, a long history of myasthenia gravis, co-existing pulmonary disease and severe (grades III and IV) myasthenia.Trans-sternal thymectomy rather than transcervical thymectomy often requires postoperative ventilation.
British Journal of Anaesthesia | CEPD Reviews | Volume 2 Number 3 2002