Clinical Image: Visual Estimation of Blood Loss

Abstract

Military prehospital providers frequently have to make important clinical decisions with only limited objective information and vital signs. Because of this, accurate estimation of blood loss, at the point of injury, can augment any available objective information. Prior studies have shown that individuals significantly overestimate the amount of blood loss when the amount of hemorrhage is small, and they tend to underestimate the amount of blood loss with larger amounts of hemorrhage. Furthermore, the type of surface on which the blood is deposited can impact the visual estimation of the amount of hemorrhage. To aid providers with the ability to accurately estimate blood loss, we took several units of expired packed red blood cells and deposited them in different ways on varying surfaces to mimic the visual impression of combat casualties.