The estimation of blood loss during burns surgery.

The estimations of blood loss and transfusion requirements during burns surgery are notoriously difficult. This clinical study investigated the effectiveness of estimates made by junior and senior burns surgeons and senior anaesthetists by comparing them with calculated blood losses. Regression analysis shows good correlation between these methods (r-value range 0.75-0.97), although 'eye-balling' the losses tends to underestimate the transfusion requirements (regression slope coefficients ranged between 0.56 and 0.87). In only five out of 46 procedures was there a need for late transfusion for an unacceptably low haemoglobin level (< 10 g/dl). This provides further empirical evidence for the clinical value of each member of the team voicing an estimate of the loss at the end of the procedure. The mean blood loss for 1 per cent of burn excised or split skin donor site harvested was 117 ml in adult cases. Blood loss can also be expressed as a mean percentage of the patient's calculated total blood volume for each 1 per cent burn excised or autograft harvested, giving figures of 2.6 per cent for adults and 3.4 per cent for children. Gravimetric analysis of soiled swabs underestimates the blood loss by approximately 50 per cent.