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?
While checking an anesthesia machine, opening the oxygen flow-control valve yields no oxygen flow, although the wall-mounted oxygen pipeline supply gauge reads 50 psig. Opening the backup oxygen cylinder results in normal oxygen flow. The most likely cause is
(A) failure of the oxygen pipeline supply
(B) failure of the second-stage oxygen pressure regulator
(C) a malfunctioning check valve in the oxygen pipeline supply inlet
After two hours of anesthesia with halothane 1.2% and oxygen, nitrous oxide 75% is added to the inspired gas mixture. This addition would
(A) increase the alveolar halothane and oxygen concentrations above inspired
(B) increase the alveolar halothane concentration only
(C) cause no change in alveolar gas concentrations compared with inspired
(D) decrease alveolar oxygen concentration compared with inspired
(E) decrease alveolar oxygen and halothane concentrations below inspired
A
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 healthy patient is receiving general endotracheal anesthesia with nitrous oxide 4 L/min, oxygen 2 L/min, and isoflurane 1% with spontaneous ventilation. The inspiratory breathing hose becomes disconnected from the inspiratory valve. The earliest alarm will be produced by
(A) a pulse oximeter with finger probe set to alarm at 60% saturation
(B) a mass spectrometer set to alarm when no breath is detected for 30 seconds
(C) an oxygen analyzer mounted on the inspiratory valve outlet and set to alarm at 25% oxygen concentration
(D) a capnograph sensor at the Y-piece that alarms when end-tidal carbon dioxide tension is greater than 60
After receiving excessive intraoperative blood replacement, a patient anesthetized with fentanyl, diazepam, and nitrous oxide develops acute pulmonary edema. The drug most likely to help him acutely is