Clinical Predictors of Gastrointestinal Bleeding Source before Computed Tomography Angiography

Acute gastrointestinal bleeding (GIB) is a commonly encountered medical emergency. In cases of negative endoscopic evaluations, computed tomography angiography (CTA) is usually the next diagnostic step. To date, data regarding positive CTA examinations are lacking. We aimed to assess the clinical and laboratory parameters that predict a positive CTA examination, as demonstrated by the extravasation of contrast material into the bowel lumen.

We performed a single-center retrospective study, including all patients who were admitted with GIB and who underwent CTA. Analysis was performed to compare patients' characteristics, and logistic regression was used to explore parameters associated with a positive CTA.

We included 154 patients. Of them, 25 patients (16.2%) had active GIB on CTA vs. 129 patients (83.8%) who did not. On univariate analysis, several parameters were positively associated with active GIB, including congestive heart failure (OR 2.47, 95% CI 1.04-5.86, p = 0.04), warfarin use (OR 4.76, 95% CI 1.49-15.21, p = 0.008), higher INR (OR 1.33, 1.04-1.69, p = 0.02), and low albumin level (OR 0.37, 95% CI 0.17-0.79, p = 0.01). On multivariate logistic regression analysis, only high INR (OR 1.34, 95% CI 1.02-1.76, p = 0.03) and low albumin (OR 0.3, 95% CI 0.12-0.7, p = 0.005) kept their positive association with active bleeding, while a high ASA score was negatively associated with an active GIB.

We could identify high INR and low albumin as strong predictors of active GIB, as demonstrated by positive CTA. On the other hand, comorbid patients classified by a high ASA score did not experience a higher rate of active GIB.