10 Random Questions
The increased resistance of severely burned patients to pancuronium is primarily due to
- (A) enhanced urinary excretion of pancuronium
- (B) decreased number of presynaptic cholinergic receptors
- (C) increased number of postsynaptic cholinergic receptors
- (D) increased rate of metabolism of pancuronium
- (E) increased volume of distribution of pancuronium
A 60-kg, 70-year-old man requires open reduction and internal fixation of an intertrochanteric fracture sustained 24 hours ago. Serum creatinine concentration is 1 mg/dl and blood urea nitrogen concentration is 40 mg/dl. The most likely cause of these findings is
- (A) acute tubular necrosis
- (B) chronic renal insufficiency
- (C) dehydration
- (D) obstruction of the bladder outlet
- (E) recent gastrointestinal hemorrhage
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
During anesthesia with nitrous oxide 65% in oxygen, fentanyl, and pancuronium, nitroprusside is administered to decrease arterial pressure to 85/50 mmHg. A decrease in PaO2 from 120 to 65 mmHg is most likely caused by
- (A) cyanide toxicity
- (B) depressed cardiac output
- (C) mild hypercarbia
- (D) metabolic acidosis
- (E) pulmonary vasodilation
The MAC of a volatile anesthetic agent is greatest when administered to which of the following groups of healthy patients?
- (A) Neonates
- (B) Infants
- (C) Adolescents
- (D) Men 30 years of age
- (E) Parturients
Which of the lines shown in the graph illustrates the relationship of hematocrit and oxygen transport?
- (A) Line A
- (B) Line B
- (C) Line C
- (D) Line D
- (E) Line E
A 65-kg man is scheduled for wrist surgery with intravenous regional anesthesia with 0.5% lidocaine 50 ml. Which of the following statements is true?
- (A) This anesthetic is contraindicated if the patient has sickle cell disease
- (B) Mottling of the skin after injection dictates abandonment of the technique
- (C) Tourniquet discomfort is an indication to inject more local anesthetic
- (D) Bupivacaine 0.5% could be substituted to prolong anesthesia
- (E) Epinephrine (1:400,000) should be added to prolong anesthesia
An 18-year-old patient with hemophilia A is scheduled for inguinal hernia repair. Preoperatively, factor VIII concentration is 60% of normal. The most appropriate management is administration of
- (A) fresh frozen plasma
- (B) cryoprecipitate
- (C) factor VIII concentrate
- (D) vitamin K
- (E) none of the above
A 62-year-old woman with polycythemia vera is scheduled to undergo total knee arthroplasty using a tourniquet. Preoperative hematocrit is 60%. Which of the following is the most appropriate action?
- (A) Perform total knee arthroplasty without use of a tourniquet
- (B) Preoperative reduction of the hematocrit to 45% to 50%
- (C) Prophylactic administration of aprotonin during surgery
- (D) Prophylactic administration of epsilon-aminocaproic acid during surgery
- (E) Prophylactic administration of low-dose heparin during surgery
A 50-year-old patient is undergoing middle ear exploration with isoflurane, nitrous oxide, and oxygen anesthesia. Ventilation is controlled; PetC02 is 35 mmHg, heart rate is 90 bpm, and blood pressure is 120/70 mmHg. Assistance is needed to minimize bleeding in the surgical field. Which of the following is the most appropriate next step in management?
- (A) Addition of 5 cmH20 positive end-expiratory pressure
- (B) Changing the anesthetic agent to halothane
- (C) Hyperventilation to a PetC02 of 20 mmHg
- (D) Placing the patient in reverse Trendelenburg position
- (E) Titration of nitroprusside to a mean arterial pressure of 55 mmHg