10 Random Questions
Prilocaine is NOT recommended for obstetric regional anesthesia because it
- (A) causes fetal methemoglobinemia
- (B) has a very short duration of action
- (C) is not metabolized by the newborn
- (D) is the most toxic of the amide local anesthetics
- (E) produces a longer motor block than sensory block
A child undergoing general anesthesia is breathing spontaneously using the Jackson-Rees modification of the Ayres T-piece. Respiratory rate is 20/min and tidal volume is 75 ml. What is the minimum fresh gas flow required to prevent rebreathing?
- (A) 750 ml/min
- (B) 1500 ml/min
- (C) 2250 ml/min
- (D) 4500 ml/min
- (E) 6000 ml/min
A 40-year-old woman is undergoing a posterior fossa craniotomy in the sitting position for clipping of a basilar artery aneurysm. Nitroprusside is being used to maintain mean arterial pressure at 50 mmHg, measured at head level. During dissection, over the course of one minute, the mean blood pressure decreases to 30 mmHg. Simultaneously, end-tidal carbon dioxide and pulmonary artery pressures decrease and heart rate increases. The most likely cause of these changes is
- (A) progressive hypoxemia
- (B) nitroprusside bolus
- (C) junctional rhythm
- (D) brain stem manipulation
- (E) venous air embolism
The supine hypotensive syndrome of pregnancy
- (A) begins at 32 weeks' gestation
- (B) causes fetal distress by aortocaval compression
- (C) is corrected by Trendelenburg's position
- (D) is less likely following subarachnoid block than epidural block
- (E) occurs in 90% of supine women at 38 to 40 weeks' gestation
A 46-year-old patient is undergoing resection of a posterior fossa tumor with the head elevated 10 cm above the level of the heart. During the procedure, the following changes in vital signs are observed. Which of the following is the most likely cause of the change in heart rate?
- (A) Brain stem compression
- (B) Increased intracranial pressure
- (C) Myocardial ischemia
- (D) Trigeminal nerve retraction
- (E) Venous air embolism
In which of the following clinical circumstances does down-regulation of beta-adrenergic receptors occur?
- (A) Chronic congestive heart failure
- (B) Hypothyroidism
- (C) Long-term clonidine administration
- (D) Long-term metoprolol administration
- (E) Stable angina
A patient receives 1.5% bupivacaine 40 ml and epinephrine 1:200,000 for axillary brachial plexus block for reduction of a forearm fracture. The tourniquet is inflated to 300 mmHg; 45 minutes later, the patient has pain that radiates to the posteromedial elbow. Which of the following nerves is NOT adequately blocked?
- (A) Intercostobrachial
- (B) Median
- (C) Musculocutaneous
- (D) Ulnar
- (E) Radial
Which of the following is most likely to decrease in the affected area following a paravertebral lumbar sympathetic block?
- (A) Cutaneous blood flow
- (B) Pinprick sensation
- (C) Sweating
- (D) Temperature sensation
- (E) Venous capacitance
Gravid uterine blood flow is
- (A) autoregulated
- (B) decreased by normotensive epidural analgesia
- (C) decreased by uterine contractions
- (D) increased with an increase in maternal Pa02
- (E) unaffected by alpha-adrenergic agonists
Compared with adults, caudal anesthesia in children is associated with
- (A) higher risk for subarachnoid puncture
- (B) more severe hypotension
- (C) more rapid onset of sensory block
- (D) smaller volume of anesthetic per kilogram of body weight
- (E) toxic effects at lower serum levels of bupivacaine