Brain death following prolonged barbiturate coma is best confirmed by
(A) electroencephalography
(B) cerebral angiography
(C) neurologic examination
(D) physostigmine trial
(E) measurement of cortical evoked potentials
B
A 50-year-old patient is undergoing craniotomy for clipping of a cerebral aneurysm with isoflurane, nitrous oxide, and fentanyl anesthesia. At the time of aneurysm exposure, the EEG shows burst suppression. Which of the following is the most likely cause?
In a patient with ventricular fibrillation refractory to repeated attempts at defibrillation and epinephrine administration, the most appropriate management is administration of
A 30-year-old, 70-kg woman with mitral stenosis is scheduled for elective laparoscopic sterilization. Preoperatively she is taking digoxin and an unknown medication for chronic mental depression. The EKG demonstrates atrial fibrillation. Heart rate is 68 bpm. Anesthesia is induced with thiopental followed by nitrous oxide 50%, halothane 0.75%, and a continuous succinylcholine infusion. The ventilator is set to deliver a minute volume of 5 liters through an endotracheal tube. As the carbon dioxide is being insufflated into the abdomen, the blood pressure is noted to be elevated (150/100 mmHg) and ventricular bigeminy is present. The most appropriate therapy is to
(A) increase the halothane concentration to 1.25%
(B) discontinue the succinylcholine infusion
(C) increase minute ventilation to 7.5 L/min
(D) administer potassium 5 mEq intravenously over one minute followed by propranolol 0.25 mg
(E) measure arterial blood gas and serum electrolyte values
A 30-kg patient with asthma is receiving general anesthesia and being mechanically ventilated with a measured tidal volume of 300 mL. Increasing the fresh gas flow from 3 L/min to 9 L/min without changing the ventilatory rate or I:E ratio will result in