Twelve hours after an uneventful hysterectomy with lidocaine epidural anesthesia, a 70-year-old woman has partial paralysis of the lower extremities. She is receiving morphine 0.5 mg/hr through an epidural catheter and is pain free. On examination, definite motor loss is noted in the lower extremities, but no other deficits are apparent. The most appropriate action at this time is to
(A) administer naloxone
(B) substitute fentanyl for morphine infusion
(C) remove the epidural catheter
(D) obtain an MRI of the lumbar spine
(E) reassure the patient
D
A 35-year-old woman undergoes a one-hour abdominal liposuction procedure under general anesthesia. During the procedure, 2000 ml of crystalloid is administered and 800 ml of fatty tissue is extracted. Thirty minutes postoperatively, blood pressure is 75/40 mmHg and heart rate is 100 bpm; SpO2 is 94% on room air. Which of the following is the most likely cause of these findings?
A 32-year-old man with acute aortic regurgitation is scheduled to undergo emergency aortic valve replacement. Heart rate is 110 bpm, blood pressure is 90/35 mmHg, and pulmonary artery occlusion pressure is 14 mmHg. Cardiac index is 2.2 L/min/m2. Which of the following is the most appropriate management?
(A) Administration of esmolol
(B) Administration of a fluid bolus before induction
(C) Infusion of dobutamine
(D) Infusion of phenylephrine
(E) Induction of anesthesia
E
Which of the following is the most likely cause of dyspnea during spinal anesthesia to a T3 sensory level?
(A) Decreased abdominal muscle tone
(B) Decreased afferent input from the thoracic wall
After weaning from cardiopulmonary bypass following mitral valve replacement, a patient's cardiac output is reported to be 3.7 L/min measured by thermodilution technique using 5% dextrose in water 10 ml at room temperature as injec-tate. This value could be falsely high if
Which of the following is characteristic of the pharmacokinetics of alfentanil?
(A) Clearance is greater than that of fentanyl
(B) Elimination half-life is normal in patients with hepatic insufficiency
(C) Protein binding is minimal
(D) The majority of alfentanil in plasma is ionized
(E) Volume of distribution is smaller than that of fentanyl
E
Prior to occlusion of any major pulmonary blood vessels during a thoracotomy, applying positive end-expiratory pressure to ventilation through the dependent lumen of a double-lumen tube and occluding the upper lumen of the tube will
(A) increase blood flow to the dependent lung
(B) increase the alveolar-arterial oxygen tension difference
Following transfusion of packed red blood cells during general anesthesia, the patient's blood pressure decreases, heart rate and temperature increase, and hemoglobinuria and diffuse oozing are observed. Which of the following is the most appropriate first step in management?