A 62-year-old man with severe emphysema was treated for the sixth time with assisted mechanical ventilation (Fi02 0.6, peak inspiratory pressure 25 mmHg, rate 22/min, insp/exp 0.3). Arterial blood gas values with this therapy are Pa02 73 mmHg, PaC02 48 mmHg, and pH 7.32. During the second day of treatment he suddenly becomes dusky, with increased respiratory rate. Arterial blood gas values are Pa02 42 mmHg, PaC02 67 mmHg, and pH 7.25. Tracheal lavage and suction fail to improve his condition. The therapeutic measure most likely to correct this acute episode is to
(A) administer heparin
(B) increase Fi02
(C) paralyze him with pancuronium
(D) add positive end-expiratory pressure 5 to 10 cmH20
(E) insert a chest tube
E
Compared with thiopental, methohexital is characterized by
Preoperative administration of alpha-adrenergic inhibitors will usually reverse ECG changes due to
(A) catecholamine myocarditis
(B) Preoperative administration of alpha-adrenergic inhibitors decreases operative mortality
(C) Beta-adrenergic inhibitors should be administered preoperatively only in conjunction with alpha-adrenergic
inhibitors
(D) Vasopressor therapy may be necessary postoperatively for treatment of hypotension
E
Immediately following radical prostatectomy, ketorolac administered for analgesia
(A) aggravates ileus and bladder spasm
(B) increases platelet adhesion
(C) is ideally suited for patient-controlled analgesia
(D) mediates its effects via kappa opioid receptors
(E) produces cyclooxygenase inhibition
E
A patient develops urticaria and pruritus while receiving a blood transfusion in the PACU. Blood pressure and heart rate are unchanged from pretransfusion values. The most appropriate action is administration of
A patient whose trachea is intubated develops partial airway obstruction two hours after induction of fentanyl, nitrous oxide, oxygen anesthesia. The anesthesiologist discontinues the nitrous oxide and controls ventilation, and there is gradual improvement during the next hour. No evidence of a respiratory disorder is found at the conclusion of the anesthetic. Which of the following is most likely?
(A) The endotracheal tube was in the right mainstem bronchus
(B) The patient had an unrecognized air embolism
(C) The patient had a nitrous oxide pneumothorax
(D) The endotracheal tube cuff narrowed the airway
A patient who is receiving ventilatory support after coronary artery bypass grafting has a PaO2 of 132 mmHg, a PaCO2 of 19 mmHg, and a pH of 7.57. Which of the following is most likely to result from this level of hypocarbia?