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%
The primary mechanism for pharmacologic reduction of intraoperative blood loss is
(A) decreased blood viscosity
(B) decreased cardiac output
(C) decreased venous return
(D) direct myocardial depression
(E) hypotension
E
A patient with lumbar disk disease requires lumbar epidural injection of a corticosteroid for control of low back pain. Which of the following statements concerning this treatment is true?
(A) Maximum effect occurs one hour after injection
(B) Maximum effect occurs when drug concentration peaks in cerebrospinal fluid
(C) Maximum effect occurs during the acute phase of the disease
(D) The beneficial effect results primarily from sympathetic neurolysis
(E) It is contraindicated if the patient has had prior surgical procedures on the lumbar disks
C
With respect to mechanical ventilation, which of the following statements concerning the portion of tidal volume known as compression volume is true?
(A) It is calculated by dividing the volume of gas delivered to the patient by the peak pressure
(B) It does not contribute to the volume of gas entering the patient
(C) It is not included in the volume measured by a spirometer on the inspiratory limb
(D) It decreases with the addition of a humidifier to the breathing circuit
(E) It decreases with the addition of one-way valves at the Y connector of the breathing circuit
Following a right lower lobectomy, a patient develops a bronchopleural fistula and becomes hypoxic. He is orally intubated and mechanically ventilated with pure oxygen. PaO2 is 65 mmHg, PaCO2 is 70 mmHg, and pH is 7.25. Which of the following will produce the most favorable change in the blood gases?