10 Random Questions
During ligation of a patent ductus arteriosus, a newborn infant receives a total gas flow of 5 L/min through a nonheated Jackson-Rees system. Operating room temperature is maintained at 30°C. The primary cause of a rapid decrease in rectal temperature from 36.8°C to 35°C is
- (A) absence of the central temperature control mechanism
- (B) conductive heat loss
- (C) convective heat loss
- (D) evaporative heat loss
- (E) radiant heat loss
Which of the following is most likely to decrease uterine tone?
- (A) Administration of isoflurane 1%
- (B) Administration of nitrous oxide 50%
- (C) Intravascular injection of 5 ml of 0.5% bupivacaine
- (D) Intravenous administration of ketamine 2 mg/kg
- (E) Paracervical block with 20 ml of 1% lidocaine
Succinylcholine can be administered safely to a patient with
- (A) amyotrophic lateral sclerosis
- (B) cerebral palsy
- (C) a pelvic crush injury sustained two weeks ago
- (D) a 20% body surface area burn sustained 10 days ago
- (E) hemiparesis one month after a cerebrovascular accident
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
Measurement of blood pressure with a Doppler device involves
- (A) reflection of ultrasound waves off blood elements
- (B) detection of oscillations in cuff pressure
- (C) amplification of Korotkoff sounds with a miniature microphone
- (D) transillumination with a near infrared light
- (E) detection of variations in blood vessel diameter
A 70-kg man with ischemic heart disease is undergoing abdominal aortic aneurysm resection. At the time of infrarenal cross-clamping, 0.2-mV ST-segment depression appears on lead V5 of the ECG. Hemodynamic changes occurring at the same time are shown below. Systemic blood pressure 90/50 --> 150/90; Heart rate 80 --> 95; PAp 20/10 --> 45/24; Mean pulmonary artery occlusion pressure (mmHg) 10 --> 23; Cardiac output (L/min) 4.5 --> 3.2. Ischemia would be decreased by restoring the pre-clamp level of each of the following EXCEPT
- (A) blood pressure
- (B) heart rate
- (C) pulmonary artery pressure
- (D) pulmonary artery occlusion pressure
- (E) cardiac output
During isoflurane anesthesia, a 45-year-old patient with chronic asthma has wheezing, prolonged expiration, sinus tachycardia of 120 bpm, and premature ventricular contractions. Preoperative medication included cromolyn and theophylline (serum level 20 jag/ml). The most appropriate treatment is to administer
- (A) albuterol aerosol
- (B) aminophylline by intravenous infusion
- (C) cromolyn aerosol
- (D) halothane
- (E) hydrocortisone by intravenous bolus
Compared with intermittent positive pressure ventilation (IPPV), intermittent mandatory ventilation (IMV)
- (A) better maintains cardiac output
- (B) provides less than full mechanical ventilatory support
- (C) requires a greater level of sedation
- (D) requires a higher FlO2
- (E) requires a lower inspiratory flow rate
Electrocautery units operate at frequencies between 300 kHz and 2 mHz to
- (A) avoid pacemaker interference
- (B) minimize ECG tracing interference
- (C) minimize the likelihood of ventricular fibrillation
- (D) optimize hemostasis
- (E) provide the best "cutting" current
A 45-year-old man is scheduled for appendectomy under general anesthesia. He reports that for many years he has occasionally felt his heart "skip a beat." The ECG tracing shown was obtained one hour ago. Which of the following is the most appropriate next step?
- (A) Proceeding with induction of anesthesia
- (B) Administration of a loading dose of digoxin
- (C) Carotid sinus massage
- (D) Intravenous administration of atropine
- (E) Placement of a temporary pacemaker