Assessment of urinary dipstick in patients admitted to an ED for blunt abdominal trauma

Clinicians still face significant challenge in predicting intra-abdominal injuries in patients admitted to an emergency department for blunt abdominal trauma. This study was thus designed to investigate the value of dipstick urinalysis in patients with blunt abdominal trauma.

We performed a retrospective, multicenter, cohort study involving patients admitted to the emergency department for abdominal traumas, examined by means of urinary dipstick and abdominal CT scan. The primary endpoint was the correlation between microscopic hematuria detected via dipstick urinalysis (defined by the presence of blood on the dipstick urinalysis but without gross hematuria) and abdominal injury, as evidenced on CT scan.

Of the 100 included patients, 56 experienced microscopic hematuria, 17 gross hematuria, and 44 no hematuria. Patients with abdominal injury were more likely to present with hypovolemic shock (odds ratio [OR]: 8.4; 95% confidence interval [CI]: 2.7-26), abdominal wall hematoma (OR: 3.1; 95% CI: 1.2-7.9), abdominal defense (OR: 5.2; 95% CI: 1.8-14.5), or anemia (OR: 3.6; 95% CI: 1.2-10.3). Moreover, dipstick urinalysis was less likely to predict injury, with just 72.2% sensitivity (95% CI: 54.8-85.8), 53.1% specificity (95% CI: 40.2-65.7), and positive and negative predictive values of 46.4% (95% CI: 33.0-60.3) and 77.3% (95% CI: 62.2-88.5), respectively.

Dipstick urinalysis was neither adequately specific nor sensitive for predicting abdominal injury and should thus not be used as a key assessment component in patients suffering from blunt abdominal trauma, with physical exam and vital sign assessment the preferred choice.