A 36-year-old construction worker is brought to the emergency room after a house frame collapsed on him. His upper thighs were trapped under a heavy wooden beam for almost two hours while his co-workers worked to free him.

Vital Signs:
- Temperature: 37.2°C (99.0°F)
- Pulse: 90
- Blood Pressure: 136/82
- Respirations: 16/min

The patient is alert and oriented but obviously in pain. There are occasional superficial abrasions on the face and arms, but no large lacerations are noted. Breath sounds are present and equal bilaterally. The heart has a normal S1 and S2. The abdomen is nontender, nondistended, and atraumatic. The patient's legs show bilateral ecchymoses and tenderness at the upper thigh. Dorsalis pedis and posterior tibial pulses are 2+, and distal leg sensation to light touch and pinprick is intact.

Laboratory Analysis:
- Na+: 145
- K+: 5.3
- Cl-: 101
- Bicarbonate: 22
- BUN: 17
- Creatinine: 1.1
- Glucose: 106

Dipstick urinalysis is unremarkable except for 4+ blood. Microscopic urinalysis shows 2 WBCs/hpf, 0 RBCs/hpf, 3 epithelial cells/hpf, and no casts.

What is the most appropriate next step in the management of this patient?

A. Intubation and mechanical ventilation
B. Bolus with 2 L i.v. 0.9% NaCl solution
C. Cystoscopy
D. Intravenous pyelogram
E. Abdominal and pelvic CT

The most appropriate next step in the management of this patient is Abdominal and pelvic CT. This will help evaluate for any potential injuries and guide further management.

Explanation:

The most appropriate next step in the management of this patient is E. Abdominal and pelvic CT. Given the mechanism of injury and the presence of bilateral ecchymoses and tenderness at the upper thigh, there is concern for possible damage to the internal organs, such as the abdomen and pelvis. An abdominal and pelvic CT scan will help to evaluate for any potential injuries, such as fractures, internal bleeding, or organ damage, and guide further management.