Oxytocin IV bolus vs infusion; haemodynamic effects in women undergoing caesarean section

ABSTRACT

Obstetric texts advocate the use of oxytocin, either intramuscularly or as a dilute infusion, but warn against the use of intravenous bolus oxytocin, fearing significant maternal hemodynamic consequences. To compare the hemodynamic effects of oxytocin given intravenous bolus versus infusion form. Randomized clinical trial. Study was conducted in main operation theatre and OPD of Combined Military Hospital, Rawalpindi. Study was carried out over a period of six months from 24-03-2009 to 23-09-2009. Total 138 patients were included in this study. Patients were divided into two groups [Group-A received oxytocin as bolus of 5 iu given as quickly as possible [approximately over 1 s] and in group-B 5 iu diluted to 20ml normal saline given over 5 minute using an infusion pump]. Each group comprised of 69 patients. Mean age of the patients in group-A was 27.3 +/- 1.8 and in group-B, 26.9 +/- 1.7. Heart rate [beast/min] effect of oxytocin given intravenous bolus vs infusion showed statistically significant difference from 1 minute to 15 minute [P<0.001]. Similarly mean arterial pressure [MAP] rate [beast/min] effect of oxytocin given intravenous bolus vs infusion also showed statistically significant difference from 1 minute to 15 minute [P<0.001]. In conclusion, we found that at elective Caesarean section, 5 iu of i.v. oxytocin results in less haemodynamic change than 5 iu diluted to 20ml normal saline given over 5 min using as an infusion pump results in less haemodynamic change than 5 iu of oxytocin given as i.v. bolus