A patient receives remifentanil 25 mcg just before retrobulbar block with 0.25% bupivacaine 4 mL. Over the next 10 minutes, he develops apnea and loses consciousness. Which of the following is the most likely explanation?
(A) Effects of remifentanil
(B) Injection of local anesthetic into cerebrospinal fluid
A 48-year-old woman underwent a posterior fossa craniotomy in the sitting position. Monitoring included precordial Doppler, arterial blood pressure, central venous pressure (CVP), and urine output. Furosemide was used intraopera-tively for cerebral decompression, and the operation was uneventful. In the recovery room, she was awake with stable vital signs when the CVP suddenly increased from 6 to 25 mmHg without any change in blood pressure. Shortly thereafter, premature ventricular contractions are noted. After administering lidocaine 1 mg/kg intravenously, the most appropriate action is to
(A) position the patient head down, right side up and aspirate the CVP catheter
(B) withdraw the CVP catheter 5 cm
(C) infuse potassium chloride rapidly
(D) administer furosemide
(E) ask the neurosurgeon to reevaluate the patient immediately
After termination of cardiopulmonary bypass, a patient who is chronically digitalized receives digoxin 0.5 mg in error. An ECG shows sinus bradycardia with intermittent sinus arrest; blood pressure is 90/60 mmHg. Which of the following drugs is contraiindicated in this patient?
Which of the following increases the cephalad spread of hyperbaric intrathecal local anesthetics?
(A) Cephalad-directed needle bevel
(B) Coughing
(C) Lithotomy position
(D) Obesity
(E) Rapid injection
D
Volume-cycled flow generators are preferred over pressure-cycled ventilators in critical care units because they
(A) have a lower compression volume
(B) limit peak airway pressure
(C) maintain constant ventilatory volume with changes in lung compliance
(D) more readily compensate for gas leaks
(E) permit more accurate measurement of the patient's minute volume
C
Which of the following findings on the left is most likely to be associated with an increased risk of complications with cannulation of the left internal jugular vein compared with cannulation of the right internal jugular vein?
(A) Longer recurrent laryngeal nerve
(B) Lower location of the cupola of the pleura
(C) More acute angle between the internal jugular and innominate veins
A 33-year-old primigravid woman with myasthenia gravis, well-controlled with pyridostigmine, is in labor with the cervix dilated 7 cm. She has a headache and feels very nervous. Blood pressure is 160/115 mmHg, she has 3+ pitting edema, and urinalysis shows 4+ protein. Appropriate management of her labor should include
(A) lumbar epidural block with bupivacaine 8 ml of 0.5% solution