A 30-kg patient with asthma is receiving general anesthesia and being mechanically ventilated with a measured tidal volume of 300 mL. Increasing the fresh gas flow from 3 L/min to 9 L/min without changing the ventilatory rate or I:E ratio will result in
Compared with the use of epidural bupivacaine 0.25% alone, the addition of fentanyl will result in
(A) increased vagal activity
(B) increased motor block
(C) increased sympathetic block
(D) more rapid onset of analgesia
(E) no change in duration of analgesia
D
A 73-year-old woman with a preoperative serum creatinine concentration of 2.1 mg/dl develops oliguria during enflurane anesthesia. Urine sodium concentration is 10 mEq/L and urine osmolality is 450 mOsm/L. The most likely cause of these findings is
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
Which of the following statements concerning variable decelerations of fetal heart rate is true?
(A) It indicates compression of the umbilical cord
(B) It indicates compression of the fetal head
(C) It indicates prematurity
(D) It is obliterated by atropine
(E) It occurs normally following epidural anesthesia
A
Three hours after undergoing coronary artery bypass grafting, an elderly man develops severe hypotension after intravenous administration of morphine 4 mg. Pulmonary artery occlusion pressure is 27 mmHg and central venous pressure is 30 mmHg. Transesophageal echocardiography shows decreased end-diastolic ventricular volumes. Which of the following is the most likely diagnosis?
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?