In a patient who is breathing spontaneously, the work of breathing increases with each of the following EXCEPT
(A) decreased compliance
(B) decreased vital capacity
(C) increased carbon dioxide production
(D) increased respiratory rate
(E) increased dead space
B
An apneic adult is receiving an oxygen flow of 4 L/min through a rigid bronchoscope. After five minutes of apnea, which of the following findings is most likely?
Four days after mitral valve replacement, a 49-year-old, 70-kg woman who has had oliguric renal failure since the operation requires insertion of a Schribner shunt for hemodialysis. Her BUN concentration is 104 mg/dl, serum creatinine is 9.3 mg/dl, serum sodium is 130 mEq/L, and serum potassium is 6.7 mEq/L. During the operation under local anesthesia, diazepam 7.5 mg and morphine 10 mg are administered intravenously to control agitation. Five minutes later while she is sleeping quietly, unifocal premature ventricular contractions appear at a rate of 10 per minute on the ECG monitor. The most appropriate therapy is to
(A) administer calcium gluconate 250 mg intravenously
A 67-year-old man is undergoing total hip replacement under general anesthesia. He had a permanent endocardial VVI pacemaker placed two years ago for complete heart block, and since arrival in the operating room has been paced continuously. Use of the electrocautery causes the pacemaker to malfunction intermittently. The most appropriate management is to
(A) tape a magnet over the pacemaker generator and convert to asynchronous mode
(B) do nothing since the pacemaker is programmed to deal with this circumstance
(C) stop the surgeon from using the electrocautery
(D) limit the surgeon to 10 sec/min electrocautery bursts
(E) place the electrocautery indifferent lead as close as possible to the pacemaker
A patient has a seizure within seconds after receiving a retrobulbar injection of 0.5% bupivacaine with epinephrine 1:200,000. Which of the following is the most likely cause?
A patient with hypokalemic familial periodic paralysis develops weakness of skeletal muscles at the end of an emergency appendectomy under spinal anesthesia. If the weakness is a result of the familial periodic paralysis, which of the following statements is true?
(A) Bicarbonate therapy is indicated
(B) Cardiac dysrhythmias are unlikely
(C) Initial treatment is intravenous edrophonium
(D) Potassium infusion is contraindicated
(E) The paralysis spares the diaphragm
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