Background: The abdomen is routinely considered as a possible source of bleeding in hypotensive and unevaluable blunt multitrauma patients. These patients are often unstable to be transported for abdominal computed tomography (CT). Emerging data on Focused Assessment with Sonography for Trauma (FAST) exam questions its initially reported high accuracy. We hypothesized that Diagnostic Peritoneal Aspiration (DPA), without a full lavage, accurately detects intraperitoneal blood if present in sufficient volume to cause hypotension and warrant emergent operation.
Methods: Over 24 months (July 2002-June 2004), 62 severe blunt trauma patients (Injury Severity Score: 32+/-17) with admission systolic blood pressure equal to or less than 90 mmHg were enrolled prospectively. Percutaneous DPA was performed after FAST. Aspiration of any quantity of blood was considered a positive test. Sensitivity and specificity of DPA and FAST were calculated against findings from abdominal CT, laparotomy, or autopsy.
Results: Twenty-two patients (35%) required emergent laparotomy and 39 (63%) died. DPA was performed in less than 1 min with no complications. Sensitivity and specificity of DPA was 89% and 100%, respectively, whereas for FAST it was 50% and 95%. Two (3%) false negative DPA were recorded; one patient had a minor liver laceration with 250 ml of free blood and the other a leaking retroperitoneal pelvic hematoma in the presence of cirrhosis with 600 ml of bloody ascitic fluid. There were no false positive DPA. Nine (14.5%) false negative and two (3%) false positive FAST were recorded in patients who were found to have at laparotomy 1575+/-1070 ml of hemoperitoneum on average.
Conclusions: Percutaneous DPA is accurate, rapid, safe, and superior to FAST for the diagnosis of abdominal blood as the source of hemodynamic instability, requiring emergent surgery, in blunt multitrauma patients.