Doppler Arterial Pressure Measurements Reliably Exclude Occult Arterial Injury in Blunt Extremity Trauma

Doppler Arterial Pressure Measurements Reliably Exclude Occult Arterial Injury in Blunt Extremity Trauma

Peter A. Cole, MD; Robert Campbell, MD; Marc F. Swiontkowski, MD; Kaj H. Johansen, MD, Harborview Medical Center University of Washington, Seattle, WA

Purpose: To determine whether a noninvasive vascular test, the Arterial Pressure Index (API), can reliably exclude occult arterial injury in patients presenting with blunt arterial trauma.

Methods: Using a Doppler probe and a standard blood pressure cuff, an API is determined by a Doppler arterial pressure measurement in the injured extremity distal to the wound, divided by a pressure measurement in an uninvolved limb.

Seventy consecutive patients with 75 injured limbs underwent doppler arterial measurement to determine API. Patients with frank arterial bleeding, a pulseless extremity, a bruit or an expanding hematoma were not included in this series. In patients with API < 0.90, the protocol included arteriographic evaluation of the injured extremity. In patients with API > 0.90, noninvasive monitoring by clinical examination and/or duplex sonography of the extremity was conducted.

Results: Among the 70 patients with 75 injured limbs, twenty (27%) presented with an initial API < 0.90. Fourteen of sixteen (88%) patients who had arteriograms performed according to protocol had evidence of arterial injury. Nine of these patients underwent operations for vascular repair. Of the other five, one died due to unrelated injuries, and four were closely monitored with serial duplex and Doppler exams until resolution.

Among the 55 limbs with an API > 0.90, clinical follow-up revealed no (0%) major or minor arterial injuries. Therefore, the negative predictive value of a Doppler API > 0.90 was 100% in this series.

Discussion: Arterial injury may complicate fractures and dislocations of the extremities. Contrast radiography is an accurate but invasive, expensive, and time-consuming means to rule out occult arterial injuries in traumatized extremities. While studies have revealed that Doppler arterial pressure measurements provide a valid screening method to exclude occult extremity arterial trauma, such studies have been based primarily on penetrating injuries. Trauma specialists thus have been slow to substitute such noninvasive studies for contrast arteriography in victims of blunt extremity trauma.

Conclusion: This data suggests that, just as for penetrating extremity trauma, noninvasive vascular tests can reliably exclude occult arterial injury in patients presenting with blunt extremity trauma. A clinical algorithm restricting contrast arteriography to blunt trauma patients with a Doppler API < 0.90 would likely be safe, accurate and cost effective.