A 67-year-old man undergoes spinal anesthesia with hyperbaric tetracaine 10 mg for transurethral resection of the prostate. At the end of the 50-minute procedure, the level of anesthesia is T6 and blood pressure is 120/70 mmHg. Within two minutes after transfer to a stretcher, the patient has nausea and blood pressure decreases to 76/42 mmHg. Which of the following is the most likely cause of the acute hypotension?
A patient who is receiving ventilatory support after coronary artery bypass grafting has a PaO2 of 132 mmHg, a PaCO2 of 19 mmHg, and a pH of 7.57. Which of the following is most likely to result from this level of hypocarbia?
During frontal craniotomy for removal of an astrocytoma, the surgeon notes that the brain is "tight." The patient is receiving nitrous oxide 50% in oxygen, isoflurane 0.5%, fentanyl, and pancuronium. Heart rate is 92 bpm, blood pressure is 110/60 mmHg, end-tidal carbon dioxide tension is 31 mmHg, and oxygen saturation is 98%. The most appropriate initial treatment is to
(A) administer a beta-adrenergic blocker
(B) administer thiopental
(C) decrease isoflurane concentration
(D) decrease mean arterial pressure to 60 mmHg
(E) increase alveolar ventilation
E
Compared with fentanyl, alfentanil is characterized by
(A) greater volume of distribution
(B) greater lipid solubility
(C) less protein binding
(D) faster redistribution
(E) longer terminal elimination phase
D
A patient suddenly makes a respiratory effort during craniotomy for clipping of a cerebral aneurysm in a 15-degree head-up position with controlled ventilation. The most likely cause is
A 30-year-old man has had burning pain, allodynia, and edema of the hand for six weeks after sustaining a forearm fracture. Appropriate treatment includes each of the following EXCEPT
(A) physical therapy, employing stress loading
(B) oral prazosin
(C) intravenous regional sympathetic block with guanethidine