After the bronchial and tracheal cuffs of a right endobronchial tube are inflated, ventilation through the tracheal lumen is not possible. This finding is most consistent with
(A) cuff occlusion of the right upper lobe bronchus
A 72-year-old patient who takes levodopa and carbidopa is undergoing colon resection. Metoclopramide is administered preoperatively and anesthesia is maintained with proposal, fentanyl, and nitrous oxide, with vecuronium for muscle relaxation. Fifteen minutes after reversal of muscle relaxation with neostigmine and atropine and tracheal extubation, the patient has dyspnea and muscular rigidity. Which of the following is the most likely cause?
(A) Central anticholinergic syndrome
(B) Fentanyl-induced rigidity
(C) Inhibition of methionine synthetase by nitrous oxide
The ECG strip shown is recorded as a patient with a permanent transvenous DDD pacemaker enters the operating room. These changes indicate that the pacemaker is
A 62-year-old woman with polycythemia vera is scheduled to undergo total knee arthroplasty using a tourniquet. Preoperative hematocrit is 60%. Which of the following is the most appropriate action?
(A) Perform total knee arthroplasty without use of a tourniquet
(B) Preoperative reduction of the hematocrit to 45% to 50%
(C) Prophylactic administration of aprotonin during surgery
(D) Prophylactic administration of epsilon-aminocaproic acid during surgery
(E) Prophylactic administration of low-dose heparin during surgery
B
As part of a preoperative evaluation, a patient had a thallium scan showing a "cold spot" over the left ventricle that occurs with moderate exercise and disappears at rest. This most likely indicates
A 70-year-old patient is shivering and has chest pain in the PACU following a cholecystectomy. Heart rate is 120 bpm, and blood pressure is 220/120 mmHg. SpO2 is 97% at an FiO2 of 0.4. An ECG shows ST-T wave changes, which are not affected by intravenous administration of nitroglycerin. Which of the following is the most appropriate next step?
The development of tachycardia is most hazardous in patients with which of the following conditions?
(A) Aortic insufficiency
(B) Cardiac tamponade
(C) Mitral insufficiency
(D) Mitral stenosis
(E) Ventricular septal defect
C
A healthy 57-year-old man with a ureteral calculus is scheduled for immersion extracorporeal shock wave lithotripsy. Which of the following statements is true?
(A) Delivery of the shock wave is timed by the R wave of the ECG
(B) Continuous epidural anesthesia is contraindicated because of the risk for infection
(C) If a regional technique is used, a T10 sensory level is required for adequate anesthesia
(D) If general anesthesia is used, high tidal volumes and low respiratory rate are preferred
(E) Removal of the patient from the bath is accompanied by an increase in blood pressure
A healthy 30-year-old woman is undergoing laparoscopy with carbon dioxide insufflation under nitrous oxide 50% in oxygen, isoflurane 0.5%, fentanyl 150 u.g, and controlled ventilation. During the first 15 minutes of the procedure, blood pressure decreases 30%. The most likely cause is