An infant with congenital lobar emphysema is scheduled for thoracotomy. Which of the following should be included in the anesthetic management of this infant?
(A) Helium-oxygen inspired gas mixture
(B) Nitrous oxide administration
(C) Positive pressure ventilation
(D) Prophylactic placement of a chest tube
(E) Spontaneous ventilation until the chest is opened
A 55-year-old man who is scheduled to undergo carotid endarterectomy (CEA) has a persistent myocardial filling defect at three hours on a dipyridamole-thallium scan. Which of the following statements is correct?
(A) Coronary autoregulation is effective in this segment
A previously healthy, 60-kg, 17-year-old boy is undergoing emergency surgery for a gunshot wound involving the iliac vein. Ventilation is controlled with a tidal volume of 700 ml/breath, rate of 10/min, and peak inspiratory pressure of 30 cmH2O. Body temperature is normal. The most likely cause of an end-tidal carbon dioxide partial pressure of 16 mmHg is
A 25-year-old man with known rheumatic heart disease is being evaluated in the critical care unit. Despite decreasing cardiac output, mixed venous blood from a pulmonary artery catheter shows an increase in Sv02. Which of the following is the most likely cause?
(A) Decreasing hematocrit
(B) Hypothermia to 35°C
(C) Metabolic alkalosis
(D) Mitral regurgitation
(E) Wedging of the catheter
E
Carbon dioxide retention first occurs when the ratio of forced expiratory volume in 1 second to vital capacity (FEV1/VC) decreases below