An otherwise healthy 16-year-old girl is undergoing posterior spinal fusion for thoracolumbar scoliosis. During the procedure, the most likely cause of a marked decrease in the amplitude of the somatosensory evoked potentials after stimulation of the posterior tibial nerve is
(A) administration of fentanyl 30 jag /kg for induction
(B) administration of isoflurane 1.3 MAC for maintenance
(C) administration of vecuronium 0.15 mg/kg
(D) a decrease in body temperature from 37 to 35°C
You see a flash of fire from the endotracheal tube of a patient undergoing carbon dioxide laser excision of laryngeal polyps. The immediate response should be to
(A) discontinue the fresh gas flow
(B) increase the nitrous oxide concentration
(C) spray water down the endoscope
(D) insert wet pads into the pharynx
(E) remove the endotracheal tube
E
Microatelectasis 48 hours after abdominal surgery is most consistently manifested by
(A) decreased PaO2
(B) ground glass infiltrate on a roentgenogram of the chest
(C) scattered fine inspiratory rales
(D) increased PaCO2
(E) scattered areas of dullness to chest percussion
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?
If administered epidurally in equipotent doses, which of the following opioids will produce analgesia over the greatest number of dermatomes?
(A) Fentanyl
(B) Hydromorphone
(C) Meperidine
(D) Morphine
(E) Sufentanil
D
In the absence of coronary artery disease, isoflurane-induced vasodilation and tachycardia are beneficial hemodynamic goals for which of the following cardiac diseases?