What is the next step in the emergency room (ER) for a patient with a thigh hematoma and weak pulses distal to the injury until a vascular surgeon arrives?

Management of Trauma with Thigh Hematoma and Weak Pulses

In a trauma patient with thigh hematoma and weak pulses distal to the injury, CT angiography (CTA) should be performed immediately as the next step in the emergency room while awaiting vascular surgery consultation.

Rationale for CTA as First-Line Approach

The presence of weak pulses distal to a thigh hematoma represents a "weak sign" of potential vascular injury that requires immediate evaluation. According to the 2021 guidelines for acute care of severe limb trauma patients, weak pulses reveal an arterial injury in 3-25% of cases 1. This clinical presentation requires either immediate surgical exploration or, if the patient is hemodynamically stable, rapid radiological examination such as CT angiography 1.

Key Decision Points:

1. Assessment of hemodynamic stability:

   • If the patient is hemodynamically stable (systolic BP ≥90 mmHg), proceed with CTA
   • If unstable (systolic BP <90 mmHg despite fluid resuscitation), immediate surgical exploration is warranted

2. Clinical indicators supporting CTA:

   • Presence of weak pulses (rather than absent pulses)
   • Hematoma near a major vascular axis
   • Non-expanding hematoma

Diagnostic Approach

The 2023 European guidelines on management of major bleeding following trauma recommend early imaging using contrast-enhanced CT for detection and identification of the source of bleeding 1. This is particularly important when:

• The bleeding source is unidentified but not requiring immediate control
• The patient is hemodynamically stable or can be stabilized during initial resuscitation

Additional Assessment:

• Calculate ankle-brachial index (ABI) - an ABI <0.9 has 87% sensitivity and 97% specificity for diagnosing vascular injury 1
• Assess for other signs of vascular compromise (pallor, neurological deficits)
• Monitor for expansion of the hematoma

When to Skip CTA and Proceed Directly to Surgery

Immediate surgical exploration without CTA is indicated when:

1. Hemodynamic instability persists despite resuscitation efforts
2. Exsanguinating hemorrhage is present from the wound
3. Absent (not just weak) pulses are detected
4. Expanding hematoma is observed
5. Obvious signs of arterial injury such as pulsatile bleeding

Management Algorithm

1. Initial assessment:

   • Evaluate hemodynamic status
   • Assess pulses, capillary refill, and neurovascular status
   • Determine if hematoma is expanding

2. For stable patients with weak pulses:

   • Proceed with CTA to evaluate vascular injury 1
   • This allows precise localization of injury and planning of surgical approach

3. While awaiting CTA or vascular surgery:

   • Avoid direct compression on suspected vascular injury
   • Monitor vital signs and distal pulses continuously
   • Prepare for possible surgical intervention
   • Position the limb in neutral alignment without constricting bandages

Pitfalls to Avoid

1. Delaying imaging in stable patients - weak pulses require prompt evaluation even if the patient appears stable
2. Excessive manipulation of the injured area - may dislodge clots and worsen bleeding
3. Missing associated injuries - fractures, nerve damage, or compartment syndrome may coexist
4. Underestimating the significance of weak pulses - this is a concerning sign that should not be dismissed

Conclusion

For a trauma patient with thigh hematoma and weak pulses distal to the injury, CTA is the appropriate next step in the emergency room while awaiting vascular surgery consultation. This approach allows for precise diagnosis and optimal surgical planning while minimizing unnecessary exploratory procedures in stable patients.