A 67-year-old man undergoes a perineal procedure under epidural anesthesia in the lithotomy position with extreme flexion of the thigh at the hip. No sedatives are used, and the surgery is uneventful. Forty-eight hours later, the patient cannot flex his left knee. Which of the following is the most likely cause?
Pseudocholinesterase
A patient with hypokalemic familial periodic paralysis develops weakness of skeletal muscles at the end of an emergency appendectomy under spinal anesthesia. If the weakness is a result of the familial periodic paralysis, which of the following statements is true?
A 36-year-old woman develops acute airway obstruction 24 hours after total thyroidectomy. The most likely cause is
A 55-year-old woman who is scheduled to undergo carotid endarterectomy has a history of essential hypertension and chronic obstructive pulmonary disease. Over a 30-minute period beginning one hour after induction of general anesthesia, Sp02 decreases from 99% to 95%. During that time, she has received fentanyl 100 mcg, isoflurane 1%, nitrous oxide 49.5%, oxygen 49.5%, and a nitroglycerin infusion to maintain blood pressure at approximately 160/95 mmHg. Which of the following is the most likely cause for the decline in oxygen saturation?
Which of the following findings is most likely in patients with acute transection of the spinal cord at the level of C6?
Five hours after intramuscular administration of morphine 15 mg to a healthy 80-kg man, residual effects are best demonstrated by measuring the
A 3-day-old infant is comatose 18 hours after surgical correction of transposition of the great vessels. Tracheal suctioning produces only a tachycardic response. Anesthesia included midazolam 0.5 mg/kg, fentanyl 60 mcg/kg, and pancuronium 0.3 mg/kg. Which of the following is the most appropriate first step in evaluation of this infant?
A patient receiving monoamine oxidase inhibitor therapy for depression undergoes an emergency cholecystectomy. Which of the following is the best means of providing postoperative analgesia in this patient?
In which of the following clinical circumstances does down-regulation of beta-adrenergic receptors occur?