A 45-year-old man is brought to the emergency department after a high-speed motorcycle col… — USMLE Step 2 CK

A $45$ -year-old man is brought to the emergency department after a high-speed motorcycle collision. On arrival, he is confused and diaphoretic.

Temperature is $35.8^\circ\text{C}$ ( $96.4^\circ\text{F}$ ), blood pressure is $78/40\text{ mmHg}$ , heart rate is $135/\text{min}$ , and respiratory rate is $28/\text{min}$ . Primary survey reveals a patent airway and equal breath sounds bilaterally. The abdomen is distended with diffuse tenderness to palpation. Pelvic compression produces gross mechanical instability. Bilateral lower extremities are cool with weak dorsalis pedis pulses.

A pelvic binder is immediately applied, and massive transfusion protocol is initiated. Following the rapid administration of $2\text{ units}$ of uncrossmatched packed red blood cells and $2\text{ units}$ of fresh frozen plasma, his blood pressure is $82/45\text{ mmHg}$ .

A focused assessment with sonography for trauma (FAST) exam demonstrates a moderate amount of anechoic fluid in the hepatorenal recess (Morison pouch). An anteroposterior pelvic radiograph shows a $4\text{ cm}$ diastasis of the pubic symphysis and widening of the right sacroiliac joint.

Arterial blood gas analysis reveals a $\text{pH}$ of $7.22$ , $\text{pCO}_2$ of $29\text{ mmHg}$ , and $\text{HCO}_3^-$ of $12\text{ mEq/L}$ .

The patient's estranged brother arrives and demands that all life-saving procedures be halted, stating the patient 'would never want to be kept alive like this.' There is no formal advance directive on file, and the patient's wife is currently unreachable.

Which of the following is the most appropriate next step in management?

Exploratory laparotomyAnswer
B
Computed tomography scan of the abdomen and pelvis
C
Pelvic angiography with embolization
D
Intravenous administration of sodium bicarbonate
E
Discontinue resuscitation efforts based on the brother's request

Answer

Exploratory laparotomy

The correct next step for this hemodynamically unstable patient with a positive FAST exam is an exploratory laparotomy. This patient is in severe hemorrhagic shock due to two major potential sources: an intra-abdominal injury and an open-book pelvic fracture. According to established trauma algorithms, while a mechanically unstable pelvic fracture requires immediate stabilization with a binder (which was performed), the presence of a positive FAST exam indicates concurrent intra-abdominal hemorrhage. Because bleeding from solid intra-abdominal organs (such as the liver or spleen) can lead to rapid exsanguination and is definitively controllable via surgery, it takes precedence. Therefore, the patient must be taken immediately to the operating room for an exploratory laparotomy. If the patient remains hemodynamically unstable after the intra-abdominal bleeding is controlled, pre-peritoneal pelvic packing or pelvic angiography can then be pursued.

Step-by-Step Solution

Identify the patient's hemodynamic status.

The patient remains in hemorrhagic shock (blood pressure

82/45\text{ mmHg}

) despite initial blood product resuscitation and application of a pelvic binder.

Determines the urgency of intervention and precludes any transport out of the resuscitation bay for advanced imaging.

Analyze the competing sources of hemorrhage.

The patient has evidence of both intra-abdominal bleeding (positive FAST) and retroperitoneal bleeding (open-book pelvic fracture).

Both are potentially fatal, but their management pathways diverge significantly and must be prioritized correctly.

Apply the Advanced Trauma Life Support (ATLS) algorithm for combined injuries.

A positive FAST in a hemodynamically unstable patient dictates that the abdomen is the most immediate threat to life.

Intra-abdominal solid organ injury causes rapid exsanguination that can be surgically controlled, whereas pelvic venous bleeding is often temporarily tamponaded by a binder.

Address the secondary clinical challenges (acid-base and ethics).

The metabolic acidosis requires definitive perfusion restoration, and the brother's request is legally insufficient to halt emergent care.

Ensures no inappropriate delays or contraindicated medical interventions occur before proceeding directly to the operating room.

Key Concept

In a hemodynamically unstable patient with a severe pelvic fracture, a positive FAST exam mandates immediate exploratory laparotomy before addressing the pelvic bleeding with angiography or pre-peritoneal packing.

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

Topics

More questions from this topic