A patient whose trachea is intubated develops partial airway obstruction two hours after induction of fentanyl, nitrous oxide, oxygen anesthesia. The anesthesiologist discontinues the nitrous oxide and controls ventilation, and there is gradual improvement during the next hour. No evidence of a respiratory disorder is found at the conclusion of the anesthetic. Which of the following is most likely?
Each of the following is an effect of electroconvulsive therapy EXCEPT
A 40-year-old woman is undergoing a posterior fossa craniotomy in the sitting position for clipping of a basilar artery aneurysm. Nitroprusside is being used to maintain mean arterial pressure at 50 mmHg, measured at head level. During dissection, over the course of one minute, the mean blood pressure decreases to 30 mmHg. Simultaneously, end-tidal carbon dioxide and pulmonary artery pressures decrease and heart rate increases. The most likely cause of these changes is
During carotid endarterectomy, blood pressure suddenly decreases from 140/90 to 80/50 mmHg. The EKG shows a heart rate of 42 bpm, with normal sinus rhythm and occasional premature ventricular contractions. The most appropriate therapy is intravenous administration of
A 72-year-old woman is somnolent one day after left carotid endarterectomy. She has smoked 2 packs of cigarettes daily for 50 years. Six weeks ago, she underwent right carotid endarterectomy. At this time, arterial blood gases while breathing room air are PO2, 45 mmHg, PCO2, 60 mmHg, and pH 7.30. Which of the following is the most likely cause of the increased PCO2?
A 19-year-old woman has severe nausea and vomiting following laparoscopy. After intramuscular administration of prochlorperazine 10 mg, she has muscle spasms in the face, neck, and tongue. Which of the following is the most appropriate management?
Each of the following statements about the blood supply of the spinal cord is true EXCEPT:
A multiparous 24-year-old woman sustains an amniotic fluid embolism during general anesthesia. The LEAST likely clinical finding is
An 18-year-old woman has knee pain during arthroscopy performed with femoral and sciatic nerve blocks for repair of a torn medial meniscus. The most appropriate management is addition of which of the following nerve blocks?
A 72-year-old man has had residual hemiparesis since having a cerebrovascular accident three years ago. Compared with the response of the unaffected limbs to nondepolarizing muscle relaxants, the hemiparetic limbs will show