One hour after an open cholecystectomy, a 42-year-old patient is hemodynamically stable and breathing spontaneously (rate 10/min and regular) at an FiO2 of 0.4. Fentanyl, isoflurane, nitrous oxide, and pancuronium were used during the procedure. Analysis of arterial blood gases (pH, pCO2, pO2) is most likely to show:
Following extubation after nasotracheal intubation for seven days, a 35-year-old man has fever, facial pain, nasal stuffiness, and purulent nasal secretions. The most likely cause is
A patient is placed in the prone jackknife position for lumbar subarachnoid injection of tetracaine 10 mg in 10 ml of preservative-free sterile water. Which of the following results is most likely?
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
A
A healthy, spontaneously breathing, supine, anesthetized patient has a PaCO2 to PetCO2 difference of 3 mmHg. Following institution of mechanical ventilation the value increases to 12 mmHg. The most likely cause of this change is
(A) cephalad displacement of the diaphragm
(B) decreased production of carbon dioxide
(C) increased cardiac output
(D) increased shunting of blood through dependent lung zones
(E) increased ventilation of nondependent lung zones
Preoperative evaluation shows a serum sodium concentration of 140 mEq/L, serum chloride concentration of 90 mEq/L, PaCO2 of 46 mmHg, and arterial pH of 7.50. These findings are most indicative of prior treatment with