During laser excision of vocal cord polyps in a 5-year-old boy, dark smoke suddenly appears in the surgical field. The trachea is intubated and anesthesia is being maintained with halothane, nitrous oxide, and oxygen. The most appropriate initial step is to
A 30-year-old woman has difficulty talking 15 minutes after initiation of interscalene block for closed reduction of a dislocated shoulder. The most likely cause is
Which of the following findings necessitates the preoperative insertion of a ventricular pacemaker in a 48-year-old man scheduled to undergo cholecystectomy?
(A) Atrial flutter with 3:1 atrioventricular block
(B) Bifascicular (right bundle branch block and left anterior hemiblock) block
(C) Left bundle branch block with first-degree atrioventricular block
An infant with congenital lobar emphysema is scheduled for thoracotomy. Which of the following should be included in the anesthetic management of this infant?
(A) Helium-oxygen inspired gas mixture
(B) Nitrous oxide administration
(C) Positive pressure ventilation
(D) Prophylactic placement of a chest tube
(E) Spontaneous ventilation until the chest is opened
A 157 cm (5 ft 2 in), 180-kg, 40-year-old woman has a PaO2 of 65 mmHg, a PaCO2 of 38 mmHg, and a pH of 7.43 while breathing room air preoperatively. The most likely cause of these values is
(A) decreased hypoxic ventilatory drive
(B) higher than normal oxygen extraction from blood
(C) lower than normal cardiac output
(D) lower than normal functional residual capacity
Which of the following statements concerning nalbuphine is true?
(A) It causes partial reversal of morphine-induced ventilatory depression
(B) Analgesia is partially mediated by delta receptor agonism
(C) Its antagonist effects are mediated at kappa receptors
(D) Duration of action is significantly shorter than that of morphine
(E) Ventilatory drive is not depressed
A
A 66-year-old man with chronic obstructive pulmonary disease who underwent colectomy 12 hours ago has been receiving an epidural infusion of fentanyl at a rate of 100 mcg/hr. Which of the following is LEAST likely to develop?