A 24-year-old man who sustained multiple rib fractures in a motor vehicle accident has air leaks through bilateral chest tubes. Which of the following is most likely following initiation of high-frequency jet ventilation?
(A) Airway pressure will be measured most reliably at the proximal (external) end of the endotracheal tube
(B) Atelectatic areas of the lungs will re-expand
(C) Changes in end-tidal carbon dioxide tension measured at the tip of the endotracheal tube will match changes in PaCOz
(D) Hypercarbia will develop
(E) The air leaks will be proportional to peak airway pressure
E
Each of the following conditions is a cause of agitation in a patient following transurethral resection of the prostate EXCEPT
(A) bladder distention
(B) glycine absorption
(C) inadequate analgesia
(D) serum sodium concentration of 127 mEq/L
(E) systolic pressure of 60 mmHg
D
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 62-year-old patient who is undergoing femoral-popliteal arterial bypass grafting during general anesthesia develops supraventricular tachycardia. Heart rate is 165 bpm and blood pressure is 90/50 mmHg. Which of the following is the LEAST appropriate treatment of the tachycardia?
(A) Adenosine
(B) Esmolol
(C) Phenylephrine
(D) Procainamide
(E) Verapamil
D
Following antagonism of a nondepolarizing muscle relaxant with neostigmine, twitch height is normal. To achieve this effect, the percentage of the acetylcholine receptor pool that must be free of muscle relaxant is
A 29-year-old man who has been nasotracheally intubated for two weeks following a motor vehicle accident has a fever (39C) and a constant headache. Leukocyte count is 18,000/mm3. The most likely cause is