Objectives: the aims of the present study were to compare the haemodynamic effects of oxytocin and carbetocin and to assess the efficacy of these two drugs in terms of blood loss and the additional uterotonic needed in caesarean section at high risk of primary post-partum haemorrhage.
Methods: women in the carbetocin group (group A) received a bolus of 100 μg IV; women in the control group (group B) received 20 IU of oxytocin in 1000 ml of 0,9% Na-Cl solution IV (150 mL/hour). The main parameter evaluated was the haemodynamic effects of drugs and the need for additional uterotonic agents. In addition we compared the drop in haemoglobin level, the uterine tone, the uterine fundal state and the diuresis.
Results: regarding the haemodynamic effects, both drugs have a hypotensive effect, but we found a greater reduction in blood pressure within the oxytocin group. Significantly more women needed additional uterotonic agents in the oxytocin group (23,5% vs 0%, p<0.01), though there was no significant difference in estimated blood loss and in the drop haemoglobin level (p>0.05). There was a significant difference in the diuresis, higher in carbetocin group (1300 ml ± 450 ml vs 1100 ml ± 250 ml, p=0.01).
Conclusions: a single injection of carbetocin appears to be more effective than a continuous infusion of oxytocin to prevent the PPH, with a similar haemodynamic profile and minor antidiuretic effect.
Keywords: carbetocin; oxytocin; post-partum haemorrhage; uterotonic drugs.