Optimization of the time and dose of intravenous syntocinon in cases of elective caesarean section under general anesthesia

ABSTRACT

Oxytocics are routinely used in an attempt to prevent excessive blood loss during cesarean section [cs]. Several investigators have evaluated the use of different doses of oxytocin during cesarean section under regional anesthesia. Since oxytocin has dose-dependent side effects, it appears prudent to use the minimal effective dose. The objective of the study is to optimize the dose and time of syntocinon infusion to prevent postpartum hemorrhage in patients undergoing elective cesarean section under general anesthesia. 504 full term pregnant women undergoing elective cesarean section under general anesthesia were randomized either to receive 5IUsyntocinon [R] [Synthetic oxytocin, Novartis-pharma] [before cs, at the start of cs,or after closure of the uterus], 10 IU syntocinon [before cs, at the start of cs, or after closure of the uterus], 20 IU syntocinon [before cs, at the start of cs, or after closure of the uterus], or infusion containing no syntocinon [control group]. The primary outcome measures were estimated blood loss [EBL], changes in hemoglobin [Hb] and in hematocrit [Hct]. Baseline characteristics in terms of age, gravidity, parity, weight, height, preoperative blood pressure, preoperative Hb and preoperative Hct were similar in all groups. The EBL was high in the control group but it was similar in all study groups and subgroups. Giving 5 IU syntocinon before or during cesarean section is preferred on giving it after in terms of significant reductions in both Hb and Hct. The results of this randomized, controlled, double blind study have demonstrated that there is no benefit on uterine tone and blood loss of administering more than 5 IU oxytocin during elective cesarean section under general anesthesia