One-compartmental biometric blood loss calculation after cesarean section.

Blood loss during cesarean section was calculated based on post-operative decrement of hemoglobin (Hb) and hematocrit (Hct) level. The model used for pregnant women was previously validated for non-pregnant women who underwent gynecological surgery. 1,068 pregnant women who underwent cesarean section and 517 women who underwent gynecological surgery were included in the study. Regression lines between collected (x) and calculated (y) blood loss in pregnant women (y = 0.164 + 0.602x) and non-pregnant (y = 0.255 + 0.750x) women were statistically parallel. This study confirmed the applicability of one-compartmental model based on the drop in Hb levels for blood loss calculations for both gynecological surgery and cesarean section. Improved methods for calculating blood loss, V after cesarean section as V = [0.0115 × body weight (kg) × ln (preoperative Hb/postoperative Hb)] + [0.1905 × height³ (m) × ln (preoperative Hb/postoperative Hb)] + 0.3158 and after gynecological surgery V = [0.004 × body weight (kg) × ln (preoperative Hb/postoperative Hb)] + [0.4624 × height ³(m) × ln (preoperative Hb/postoperative Hb)] + 0.0472 were suggested.