Prophylactic use of uterotonic drug combos does not reduce need for more

Prophylactic administration of oxytocin plus ergonovine or oxytocin plus carboprost is not necessarily effective for decreasing the need for additional uterotonics at caesarean delivery for arrested labour as compared with oxytocin alone, a study has found.

A total of 100 women were randomized to receive an infusion of oxytocin 5 units alone (n=35) or with ergonovine 0.25 mg administered intravenously (n=33) or carboprost 0.25 mg given as an intramuscular injection (n=32) immediately after delivery, followed with maintenance infusion of oxytocin 40 milliunits/minute in all groups.

Uterine tone was evaluated at 3, 5, and 10 minutes after delivery, and additional uterotonics were administered if deemed necessary.

The primary outcome of intraoperative need for additional uterotonics was similar across the treatment groups: 37 percent among women who received oxytocin alone, 33 percent among those given oxytocin plus ergonovine, and 34 percent among those who were administered oxytocin plus carboprost (p=0.932).

Results for the secondary outcomes followed a similar pattern. There were no between-group differences seen in uterine tone and calculated blood loss.

Meanwhile, nausea or vomiting occurred with greater frequency in the oxytocin plus ergonovine or oxytocin plus carboprost combination groups than in the monotherapy group (85 percent and 72 percent vs 51 percent). The corresponding odds ratios were 5.3 (95 percent confidence interval [CI] 1.7–16.9; p=0.003) and 2.4 (95 percent CI, 0.9–6.7; p=0.086).