10 Random Questions
Left ventricular subendocardial perfusion pressure is best estimated by the difference between
- (A) mean arterial and central venous pressures
- (B) diastolic arterial and pulmonary artery occlusion pressures
- (C) mean arterial and pulmonary artery occlusion pressures
- (D) systolic arterial and pulmonary artery occlusion pressures
- (E) diastolic arterial and central venous pressures
A 45-year-old woman with mitral stenosis is scheduled for elective mitral valve replacement. Two minutes after tracheal intubation, she develops atrial fibrillation with a ventricular response rate of 150 bpm and a decrease in blood pressure to 75/45 mmHg. Which of the following is the most appropriate first step in management?
- (A) Increasing the concentration of enflurane
- (B) Increasing the infusion rate of lactated Ringer's solution
- (C) Intravenous administration of digoxin
- (D) Intravenous administration of propranolol
- (E) Electrical cardioversion
The ECG rhythm shown developed during cholecystectomy in a 62-year-old man who had a myocardial infarction and is taking atenolol. The drug of choice for treating this dysrhythmia is
- (A) atropine
- (B) bretylium
- (C) isoproterenol
- (D) lidocaine
- (E) procainamide
Intraoperative heat loss in an unclothed, undraped patient is caused primarily by
- (A) conduction to colder objects
- (B) convective heat loss
- (C) insensible perspiration
- (D) radiant heat loss to the environment
- (E) respiratory tract water loss
Which of the following statements regarding fetal heart rate patterns is true?
- (A) Early decelerations suggest umbilical cord compression
- (B) Fetal heart rates between 160 and 180 bpm are normal
- (C) Fetal heart rate unaffected by uterine contraction suggests fetal well-being
- (D) Late decelerations indicate inadequate uteroplacental perfusion
- (E) Variable decelerations indicate need for urgent delivery
During an operation with cardiopulmonary bypass using a bubble oxygenator, the risk for systemic gas embolization increases when
- (A) a filter greater than 20 microns is used in the arterial infusion tubing
- (B) gas flow to the oxygenator is decreased below 3 L/min
- (C) the operation is a mitral valve replacement
- (D) the blood level in the oxygenator reservoir exceeds 1 liter
- (E) ventricular fibrillation occurs
Compared with halothane, desflurane has which of the following characteristics?
- (A) Greater potency
- (B) A higher boiling point
- (C) Increased blood solubility
- (D) Less airway irritability
- (E) Less biodegradation
Which of the following is the most likely cause of postural headache following spinal anesthesia?
- (A) Meningeal traction
- (B) Parasympathetic (vagal) block
- (C) Sympathetic block-induced hypotension
- (D) Transtentorial cerebral herniation
- (E) Vasopressin-induced vasoconstriction
Which of the following is an effect of hypothermia in neonates?
- (A) Decreased duration of neuromuscular blockade
- (B) Increased narcotic requirements
- (C) Increased pulmonary vascular resistance
- (D) Metabolic alkalosis
- (E) Shivering
Which of the following factors is the major cause of hypotension following release of the infrarenal aortic cross-clamp during aortic reconstruction?
- (A) Abnormal myocardial function
- (B) Decreased systemic vascular resistance
- (C) Down-regulation of adrenergic receptors
- (D) Increased PaCO2
- (E) Suppression of the renin-angiotensin system