Preoperative administration of alpha-adrenergic inhibitors will usually reverse ECG changes due to
(A) catecholamine myocarditis
(B) Preoperative administration of alpha-adrenergic inhibitors decreases operative mortality
(C) Beta-adrenergic inhibitors should be administered preoperatively only in conjunction with alpha-adrenergic
inhibitors
(D) Vasopressor therapy may be necessary postoperatively for treatment of hypotension
E
A 54-year-old man is scheduled for open reduction of a fracture sustained when he jumped from a burning building. The carboxyhemoglobin concentration is 25%. Which of the following is the most reliable indicator of adequate oxygenation during general anesthesia?
(A) PaO2 of 300 mmHg
(B) pH of 7.38 with a PaCO2 of 41 mmHg
(C) Mixed venous PO2 of 45 mmHg
(D) Oxyhemoglobin saturation of 100% measured by co-oximeter
A 4-year-old child with myelomeningocele and a ventriculoperitoneal shunt is scheduled for bladder augmentation. One year ago, hypotension and bronchospasm occurred during laparotomy for placement of a feeding gastrostomy and responded to fluids and epinephrine. At that time, anesthesia was induced with thiopental, the trachea was intubated with a polyvinyl tracheal tube following administration of succinylcholine, and anesthesia was maintained with halothane and nitrous oxide. No diagnostic tests were performed after that incident. Which of the following should be avoided during the bladder augmentation?
A 76-year-old man has a leaking abdominal aortic aneurysm. His blood pressure and pulse have remained stable for 15 minutes at 90/60 mmHg and 130 bpm, respectively. His hemoglobin concentration is 11 g/dl, and the EKG shows a left bundle branch block. Induction of anesthesia should proceed
(A) after a pulmonary artery catheter has been inserted and the pulmonary artery occlusion pressure is greater than 7 mmHg
(B) when the pulse has decreased below 130 bpm from the rapid transfusion of blood
(C) when systolic blood pressure has increased to more than 120 mmHg from the rapid infusion of lactated Ringer's solution
(D) immediately on arrival in the operating room
(E) when circulatory signs deteriorate or cease to improve with rapid volume expansion
The development of tachycardia is most hazardous in patients with which of the following conditions?
(A) Aortic insufficiency
(B) Cardiac tamponade
(C) Mitral insufficiency
(D) Mitral stenosis
(E) Ventricular septal defect
C
A 50-year-old patient is undergoing middle ear exploration with isoflurane, nitrous oxide, and oxygen anesthesia. Ventilation is controlled; PetC02 is 35 mmHg, heart rate is 90 bpm, and blood pressure is 120/70 mmHg. Assistance is needed to minimize bleeding in the surgical field. Which of the following is the most appropriate next step in management?
(A) Addition of 5 cmH20 positive end-expiratory pressure
(B) Changing the anesthetic agent to halothane
(C) Hyperventilation to a PetC02 of 20 mmHg
(D) Placing the patient in reverse Trendelenburg position
(E) Titration of nitroprusside to a mean arterial pressure of 55 mmHg
D
During direct intra-arterial measurement of blood pressure
(A) the mean arterial pressure will be unaffected by small air bubbles in the system
(B) an underdamped system will overestimate the mean arterial pressure
(C) an underdamped system will overestimate the diastolic pressure
(D) long tubing from the catheter to the transducer will tend to decrease resonance in the system
(E) calibration of the transducer by opening a stopcock to air at the sternal angle will overestimate the mean