A 69-year-old man is confused and agitated one hour after preoperative intramuscular administration of scopolamine for awake fiberoptic laryngoscopy. SpO2 measured by pulse oximetry is 97%. Which of the following drugs is most appropriate for treatment of the change in mental status?
A woman with chronic obstructive pulmonary disease is extubated and minimally responsive after isoflurane anesthesia. She is receiving oxygen 6 L/min through a face mask. Respirations are 10/min, PaO2 is 68 mmHg, PaCO2 is 54 mmHg, and pH is 7.28. The most likely cause of the respiratory acidemia is
(A) blunted sensitivity to low pH in the medullary respiratory center
(B) chronic carbon dioxide retention
(C) decreased lung volume from supine positioning
(D) depression of carotid body chemoreceptors by halothane
(E) suppression of hypoxic ventilatory drive by supplemental oxygen
Each of the following increases cardiac output EXCEPT
(A) an arteriovenous fistula
(B) fever
(C) normovolemic anemia
(D) shivering
(E) carotid sinus stimulation
E
A 40-year-old woman has continuous nondermatomal burning pain of the distal foot four weeks after sustaining a metatarsal fracture. On examination, the foot is mildly swollen, tender, and cool. Which of the following statements concerning this condition is true?
(A) A radiograph of the distal bones of the painful foot will show severe osteoporosis
(B) A technetium scan of the distal joints of the painful foot will show decreased uptake
(C) Early use of opioid analgesia will prevent progression of the symptoms
(D) Intravenous phentolamine will relieve the pain
(E) The chance of spontaneous recovery within eight weeks is greater than 80%
A 62-year-old man, who had a myocardial infarction three years ago, complicated by congestive heart failure and renal failure, is undergoing a colectomy. A pulmonary artery catheter demonstrates a cardiac output higher than measurements recorded during a cardiac catheterization two months after the infarction. Which of the following most likely contributes to the increased cardiac output?
(A) Creation of an arteriovenous fistula
(B) Increased hemoglobin concentration from 10 to 12 g/dl
(C) Stimulation of carotid body receptors
(D) Transcutaneous nitroglycerin
(E) Use of a beta-adrenergic blocker to prevent myocardial reinfarction