# Prognostic relevance of contrast extravasation in patients undergoing endovascular embolization of acute bleeding

## TL;DR

This study shows that a CT-measured bleeding rate is a strong predictor of blood transfusion needs and 30-day survival in patients with acute bleeding undergoing embolization.

## Contribution

The study identifies CT-defined bleeding rate 'k' as a novel independent prognostic factor for outcomes in acute bleeding patients.

## Key findings

- Bleeding rate k was independently associated with massive transfusion (OR 25.77) and 30-day mortality (OR 25.04).
- Contrast extravasation volume alone did not correlate with transfusion requirements.

## Abstract

Contrast extravasation on imaging studies is a clinical surrogate for bleeding severity. However, the prognostic relevance of this imaging sign needs to be evaluated. The aim of this study was to analyze the impact of contrast extravasation defined by computed tomography (CT) and angiography on massive transfusion and 30-day mortality in patients with acute bleeding undergoing transarterial embolization (TAE).

A mixed cohort of patients with acute bleeding requiring treatment with TAE between 2018 and 2022 was retrospectively evaluated. All patients underwent triphasic CT to localize the source of bleeding and to calculate extravasation volumes in the arterial and portal venous phases. The bleeding rate k was calculated from the CT images.

A total of 128 patients (79 male, 61.7%) with a mean age of 67.4 years (range 21–95 years) and an all-cause 30-day mortality rate of 34.4% were included in the present analysis. A moderate positive correlation was identified between transfused packed red blood cell units and bleeding rate k (r = 0.33, p < 0.001). However, no correlation was found between transfused packed red blood cell units and arterial and portal venous extravasation volume. In multivariable logistic regression analysis, bleeding rate k was identified as an independent prognostic factor for massive transfusion (OR 25.77, 95% CI 1.35–493.61, p = 0.031, area under the receiver operating characteristic curve (AUROC) of the model: 0.847) and 30-day mortality (OR 25.04, 95% CI 2.29–273.42, p = 0.008, AUROC of the model: 0.781).

CT-defined bleeding rate, k, is a prognostic factor for massive transfusion and 30-day mortality in patients with acute bleeding undergoing TAE and may be superior to the volume of contrast extravasation volume alone. Further studies are needed to confirm this finding.

Question
Does contrast media extravasation on CT have a prognostic role in patients with acute bleeding?

Findings
Bleeding rate, k, was identified as an independent prognostic factor for massive transfusion (OR 25.77) and 30-day mortality (OR 25.04).

Clinical relevance
Diagnostic triphasic CT can be used to provide prognostic information of patients with acute bleeding.