A method for estimating the volume of blood lost during surgical procedures or trauma is a valuable tool in clinical settings. These techniques often involve visual estimation, gravimetric analysis (measuring the weight of blood-soaked materials), and calculation based on vital signs and hematocrit levels. For example, the estimated blood loss can be determined by weighing surgical sponges before and after use, with the difference converted to volume using a conversion factor (typically 1 gram equals 1 milliliter).
Quantifying shed blood is critical for guiding transfusion decisions, monitoring patient stability, and improving outcomes. Accurate assessment helps prevent both under-transfusion, which can lead to inadequate oxygen delivery, and over-transfusion, which carries risks such as transfusion-related acute lung injury (TRALI) and circulatory overload. Historically, relying solely on visual estimation has proven inaccurate; therefore, incorporating objective measurements into the assessment process offers considerable advantages. This has led to the development and refinement of various methods to improve accuracy and clinical utility.
