How does blood loss relate to the extent of surgical wound excision?

Quantification of intraoperative blood loss based on visual estimates, gravimetric methods (weighing sponges) or measurement of hemoglobin concentrations is known to be inaccurate [1 –3]. While hemoglobin values can help quantify blood loss in normovolemic patients, these values can be confounded by changes in blood volume during and after surgical procedures. Anesthetic agents, fluid administration, insensible losses, temperature and other factors affect the blood volume and consequently the ability of the hemoglobin concentration to reflect the extent of surgical blood loss [4,5].
Source: Burns : Journal of the International Society for Burn Injuries - Category: Cosmetic Surgery Authors: Source Type: research