A Fluotec vaporizer is set to administer halothane 4% using a fresh gas flow of 4 L/min. If the diluent gas flow is increased to 8 L/min, and at the same time the room temperature increases from 20 to 25°C, the approximate concentration of halothane delivered to the patient would be
Which of the following is the strongest indication for one-lung ventilation?
A 64-year-old, 87-kg woman in good general health is undergoing a right knee arthroplasty while in the supine position with general anesthesia consisting of enflurane 2% and nitrous oxide 50% in oxygen. She is breathing spontaneously through a 7-mm endotracheal tube. During the first 30 minutes of the procedure, the arterial oxygen saturation measured by pulse oximetry decreases from 98% to 92%. The most likely cause of the desaturation is
A man with alcoholic cirrhosis and a hemoglobin concentration of 10 g/dl has an intraoperative PaO2 of 75 mmHg at an FiO2 of 0.5. Which of the following is the most likely cause of the low PaO2?
A woman at 39 weeks' gestation has been in labor for 12 hours. She has had nausea and vomiting for the past eight hours. Maternal arterial blood gas values are PaO1 85 mmHg, PaCO2 31 mmHg, and pH 7.50. Which of the following is the most likely cause of fetal distress occurring at this time?
Which of the following is an effect of hypothermia in neonates?
A patient has sudden cardiopulmonary arrest five minutes after retrobulbar block with 0.75% bupivacaine 2 ml with hyaluronidase for ophthalmologic surgery. No premonitory changes were noted on the pulse oximeter. The most likely cause is
A 57-year-old man has back pain, a heart rate of 90 bpm, decreased pulse in the left arm, and blood pressure of 200/110 mmHg. During infusion of nitroprusside, heart rate increases to 115 bpm and blood pressure decreases to 140/80 mmHg. The most appropriate management at this time is administration of
A 2.8-kg 8-hour-old infant undergoes laparotomy for a ruptured omphalocele. Following primary closure of the abdominal wall, arterial blood gases are PaO2 40 mmHg (FiO2 0.6), PaCO2 55 mmHg, and pH 7.1. Blood pressure is 30/20 mmHg. After increasing the FiO2, the most appropriate action would be to
A previously healthy, 60-kg, 17-year-old boy is undergoing emergency surgery for a gunshot wound involving the iliac vein. Ventilation is controlled with a tidal volume of 700 ml/breath, rate of 10/min, and peak inspiratory pressure of 30 cmH2O. Body temperature is normal. The most likely cause of an end-tidal carbon dioxide partial pressure of 16 mmHg is