///2017 Abstract Details
2017 Abstract Details2019-08-02T15:54:53-06:00

Comparison of carbetocin administration by bolus or infusion on maternal vascular resistance during cesarean delivery: a randomized controlled trial using ccNexfin®

Abstract Number: O-06
Abstract Type: Original Research

Abby Medniuk MB BS BSc FRCA1 ; Simon Massey MB BS FRCA FRCPC2; Alison Dube BSc3; Arianne Albert PhD4; Vit Gunka MD FRCPC5


The Society of Obstetricians & Gynecologists of Canada recommends carbetocin to prevent post-partum hemorrhage at elective cesarean delivery (CD).1 Its side effects include hypotension, tachycardia, flushing, nausea & vomiting,2 likely due to reduced vascular resistance.3 The purpose of our study was to ascertain if the cardiovascular and clinical effects of carbetocin are influenced by its rate of administration; we hypothesized that administering carbetocin slower than currently recommended would reduce its cardiovascular and adverse effects.


Healthy parturients electing for CD under spinal anesthesia were randomized to receive 50mcg carbetocin after cord clamping either by 30 second bolus (Group B) or 5 minute infusion (Group I).

Parturients received similar spinal & fluid regimens. Variable rate phenylephrine infusion (PEI) kept each parturient’s blood pressure within 10% of baseline following her spinal; after peritoneal incision the PEI was fixed so it was constant during the study period. Maternal hemodynamic data were recorded using a ccNexfin® monitor (Edwards Lifesciences LLC, Canada). The primary outcome was change in maternal systemic vascular resistance index (ΔSVRI) over ten minutes following carbetocin, analyzed using linear mixed-model regression; secondary outcomes were incidence of side effects, adequacy of uterine tone and need for further uterotonics, analyzed using Fisher’s Exact test.


Forty eight parturients were analyzed (group B = 23, group I = 25). There was no difference in overall ΔSVRI over ten minutes (Fig 1a). ΔSVRI was greater (p<0.0001) in group B than group I at 1 minute, this difference was attenuated by 2 minutes (Fig 1b). Side effects occurred in 74% in group B & 52% in group I (p>0.05); adequacy of uterine tone and additional uterotonic requirements were similar between groups.


Healthy parturients having elective CD under spinal experience no difference in overall ΔSVRI whether carbetocin is given by bolus or infusion over five minutes; however, there is a significant difference in the first two minutes. Whilst not associated with an observed difference in side effects, less healthy parturients might not tolerate this change; giving carbetocin by infusion may be safer and is as effective in this population. Further studies are needed to evaluate its effect in emergency CD.


1. J Obst Gyn Can 2009;31(10):980–993

2. CJA 2014;61:242-48

3. IJOA 2010;19:313–319

SOAP 2017