Comparison of subjective estimates by surgeons and anaesthetists of operative blood loss.

Altogether 100 cases were studied to compare the subjective estimates of operative blood loss by anaesthetists (six in number) and by surgeons (22 in number). Their estimates were compared with the blood loss measured by a colorimetric method, which was assumed to be the operative blood loss. The results showed that surgeons are less reliable judges of operative blood loss then anaesthetists. When objective measurement of operative blood loss is impracticable the anaesthetist and the surgeon should jointly make a subjective estimation.