Use of Supplementary Oxtocics Following Cesarean Section
Abstract Number: 184
Abstract Type: Original Research
Introduction - Oxytocin has been used routinely after cesarean section (LSCS) but an optimal dose is yet to be decided upon. It has been hypothesised that oxytocin receptors may become desensitized following oxytocin infusion, in cases of failure of progression of labor. Repeated doses of oxytocin are often used in an attempt to optimise uterine tone after delivery, which is often futile and may be best tackled by alternative oxytocics.
Method - In 2009, data was collected on the use of supplementary oxytocics for all 1445 LSCSs in our obstetric unit. After a standard bolus dose of 5u oxytocin and initiation of 40u over 4 hours, uterine tone was clinically assessed intraoperatively by the obstetrician. If unsatisfactory, then rather than repeat doses of oxytocin, patients received either ergometrine or carboprost at the discretion of the clinicians.
Results - As seen in the table, 7.8% of elective LSCS received either ergometrine, carboprost or both. In the emergency LSCS group, where the patient was not in labor, 12.9% received supplementary oxytocics, compared with 19.3% where the indication was fetal distress and 29.1% where LSCS was performed for failure to progress in labor.
Discussion - It is surprising just how frequently supplementary oxytocics were required, even in the non-laboring LSCS, and we haven't seen data of this nature previously published. It is likely that most of those who had LSCS for delay were augmented with oxytocin infusions in labor. The fact that nearly one third of this population required supplementary oxytocics, almost four times as many as in elective cases, lends support to the theory that oxytocin receptors become desensitized. Supplementary oxytocics appear to be used with relative frequency, particularly after failure to progress in labor, and further investigation is warranted to determine optimal first and second line uterotonics, as well as dosing regimens.
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