A 16-year-old girl is receiving isoflurane, nitrous oxide, oxygen, and pancuronium for insertion of a Harrington rod. In order to perform a "wake-up test" the muscle relaxant was antagonized with neostigmine 2.5 mg and atropine 1 mg. The patient abruptly moved all extremities and was given thiopental 100 mg and succinylcholine 100 mg rapidly. Forty-five minutes later no twitch could be elicited with a nerve stimulator. The most likely explanation is
(A) a dibucaine number of 20
(B) incomplete antagonism of pancuronium
(C) prolongation of the action of succinylcholine by neostigmine
(D) spinal cord damage caused by the abrupt arousal
(E) synergism between succinylcholine and pancuronium
A 35-year-old woman who takes a diuretic daily for chronic hypertension has a serum potassium concentration of 3.1 mEq/L on the morning of an elective hysterectomy. An EKG shows left ventricular hypertrophy. The most appropriate management is to
(A) consult with a cardiologist before proceeding
(B) initiate oral potassium replacement and proceed with the operation when potassium concentration is normal
(C) initiate intravenous potassium replacement and proceed with the operation
(D) initiate intravenous potassium replacement and proceed with the operation when potassium concentration is 4 mEq/L
(E) proceed with the operation without intervention
E
A 32-year-old man is scheduled for hernia repair. He underwent heart transplantation for cardiomyopathy five years ago. Which of the following findings is most likely?
(A) Absence of coronary atherosclerosis
(B) Biventricular hypokinesis on echocardiography
(C) Down-regulation of cardiac beta-adrenergic receptors
A 77-year-old woman is still intubated and breathing spontaneously following a total hip replacement. The muscle relaxant has been reversed. Tidal volume is 400 ml, end-tidal carbon dioxide tension is 45 mmHg, and SpO2 is 98% at an FiO2 of 1.0. On transfer from the operating table to the gurney, heart rate increases from 65 to 100 bpm and blood pressure decreases from 130/80 to 80/50 mmHg. End-tidal carbon dioxide tension is 30 mmHg and SpO2 is 94%. The most likely diagnosis is
An adult patient with atrial fibrillation develops pulseless ventricular tachycardia wfiile undergoing synchronized electirical cardioversion. Which of the following is the most appropriate management?
(A) Intravenous administration of adenosine
(B) Intravenous administration of a bolus of lidocaine followed by electrical cardioversion
(C) Immediate repeat synchronized cardioversion at the same energy level
(D) Immediate repeat synchronized cardioversion at twice the previous energy level
A 68-year-old patient is undergoing total hip replacement during general anesthesia using positive pressure ventilation and neuromuscular blockade. Intraoperative monitoring shows a gradual decrease in end-tidal CO2, an increase in exhaled tidal volume, and an increase in measured FiO2. Which of the following is the most likely cause of these changes?
(A) Air entrainment around a deflated endotracheal tube cuff
(B) Channeling of the exhaled air through the carbon dioxide canister
(C) Fat embolism
(D) Inadequate muscle relaxation with spontaneous patient ventilation