A 35-year-old woman receiving isoflurane anesthesia suddenly develops tachycardia, hypertension, and multifocal ventricular ectopy during dissection of a pheochromocytoma. Each of the following would be appropriate treatment EXCEPT
(A) administration of an alpha-adrenergic blocker
(B) administration of a beta-adrenergic blocker
(C) administration of lidocaine
(D) administration of nitroprusside
(E) switching from isoflurane to enflurane
E
To eliminate involuntary expulsive effort with contraction in the second stage of labor, a nerve block must include at least
A 70-year-old man with stable angina is scheduled for cataract removal with a retrobulbar block. After injection of 5 ml of 0.75% bupivacaine, heart rate decreases from 90 to 55 bpm, and frequent premature ventricular contractions are noted on the EKG. These changes are most likely caused by
Eight hours after abdominal surgery, a 51-year-old patient becomes increasingly somnolent. Epidural morphine 5 mg was administered immediately following the procedure. Postoperatively, respiratory rate has not decreased below 12/min and Sp02 has remained greater than 92%. Arterial blood gas analysis shows Pa02 80 mmHg, PaC02 82 mmHg, and pH 7.1. Which of the following is the most appropriate conclusion?
(A) Analysis of the blood sample was delayed
(B) The blood sample was venous rather than arterial
(C) The patient is receiving supplemental oxygen
(D) The pulse oximeter readings are falsely high
(E) No treatment is required at this time
C
Which of the following statements concerning carbon monoxide poisoning is true?
(A) Diagnosis is excluded if the PaO2 is greater than 300 mmHg while breathing 100% oxygen
(B) Increased inspired oxygen concentration accelerates displacement of carbon monoxide from hemoglobin
(C) Methylene blue decreases binding of carbon monoxide to hemoglobin