1. A method for managing blood loss of a patient, comprising: receiving an image of a physical sample; extracting a feature from an area of the image corresponding to the physical sample; estimating a blood volume indicator of the physical sample according to the extracted feature; estimating a patient blood loss based on the blood volume indicator; estimating a euvolemic patient hematocrit based on an estimated patient blood volume and the estimated patient blood loss; receiving a measured patient hematocrit; and generating a volemic status indicator based on a comparison between the measured patient hematocrit and the estimated euvolemic patient hematocrit.