10 Random Questions
Which of the following statements best describes the decrease in cerebral metabolic rate that occurs with administration of volatile anesthetics?
- (A) It is independent of anesthetic dose
- (B) It is maximal when the EEG is isoelectric
- (C) It is more profound with halothane than isoflurane at equipotent doses
- (D) It is not affected by enflurane-induced EEG hyperactivity
- (E) It parallels changes in cerebral blood flow at mean arterial pressures of 50 to 150 mmHg
The ECG tracing shows
- (A) aberrant intraventricular conduction
- (B) acceleration of phase 4 depolarization of the sinus node
- (C) a compensatory pause
- (D) initiation of re-entrant supraventricular tachycardia
- (E) paroxysmal atrial fibrillation
Which of the following is the most likely effect of infrarenal cross clamping of the aorta without pharmacologic manipulation?
- (A) Decreased cardiac output
- (B) Decreased pulmonary artery occlusion pressure
- (C) Increased left ventricular stroke volume
- (D) Increased renal blood flow
- (E) Improved myocardial oxygen supply-demand ratio
Depression of cerebral oxygen requirements below the level required to create an isoelectric EEG can be achieved by
- (A) administration of isoflurane
- (B) administration of nimodipine
- (C) barbiturate coma
- (D) hyperventilation
- (E) hypothermia
Which of the following is LEAST likely to decrease myocardial oxygen supply?
- (A) Administration of enflurane
- (B) Epidural anesthesia to a sensory level of T6
- (C) Increased pulmonary artery occlusion pressure
- (D) Hypocarbia (PaCO, 25 mmHg)
- (E) Metabolic acidosis (pH 7.20)
Five minutes after a stellate ganglion block is performed, a patient becomes restless, then apneic. The most likely cause is
- (A) paratracheal hematoma
- (B) phrenic nerve block
- (C) recurrent laryngeal nerve block
- (D) subarachnoid injection
- (E) vertebral artery injection
Compared with epidural morphine, intrathecal morphine produces
- (A) better relief of visceral pain
- (B) greater loss of analgesia after administration of naloxone
- (C) less pruritus
- (D) less urinary retention
- (E) more respiratory depression
A 30-year-old woman has an abrupt change from sinus to nodal rhythm with unchanged heart rate on ECG during induction of halothane anesthesia. Which of the following is the most likely result of this change?
- (A) Decreased jugular venous pulsation
- (B) Decreased mean arterial pressure
- (C) Decreased systemic vascular resistance
- (D) Increased cardiac output
- (E) Increased pulse pressure
A 35-year-old patient, who is ASA physical status 1, is scheduled for open cholecystectomy under general anesthesia. Which of the following end-tidal concentrations would most likely block the adrenergic response to skin incision?
- (A) Enflurane 1.7%, oxygen
- (B) Isoflurane 1.2%, oxygen
- (C) Enflurane 0.6%, nitrous oxide 70%, oxygen
- (D) Halothane 0.4%, nitrous oxide 70%, oxygen
- (E) Isoflurane 1.0%, nitrous oxide 70%, oxygen
Arterial pressure in the radial artery is 155/70 mmHg measured by a correctly calibrated catheter-transducer system. At the same time aortic pressure is 140/75 mmHg using a high-fidelity catheter tip transducer. The most likely cause of this discrepancy is
- (A) a large amount of air in the dome of the radial artery transducer
- (B) coarctation of the aorta
- (C) peripheral vascular constriction produced by sympathetic stimulation
- (D) physiologic amplification of the wave form from the aorta to the radial artery
- (E) too high a frequency response in the catheter-transducer system