Intravenous dexmedetomidine and blood loss during cesarean delivery under neuraxial anesthesia: a single-center...

Intravenous dexmedetomidine may be given to reduce shivering and discomfort during cesarean delivery under neuraxial anesthesia. Dexmedetomidine lowers heart rate and blood pressure, reduces catecholamine release, may have a uterotonic effect, which could reduce intraoperative bleeding during cesarean delivery.

We conducted a single-center retrospective cohort study of cesarean delivery cases under neuraxial anesthesia conducted at a tertiary hospital in Japan between January 2012 and December 2016. Dexmedetomidine infusion was started after umbilical cord clamping at 6 μg/kg/h to reduce visceral pain over 10 min, followed by a dose reduction to 0.4 μg/kg/h until peritoneal closure. The primary outcome was quantitative intraoperative blood loss. Secondary outcomes were calculated blood loss (Gross and hemoglobin-balance methods), and intraoperative transfusion. Stabilized inverse-probability weighting based on a propensity score constructed from prespecified pretreatment covariates and estimated adjusted mean differences was conducted.

Among 790 cases (dexmedetomidine n=374; no dexmedetomidine n=416), covariate balance after weighting was good. Dexmedetomidine was not associated with blood loss (weighted mean difference + 57 mL; 95% confidence intervals - 39 to 153). Results were directionally consistent for calculated blood-loss measures; transfusion of blood products did not differ.

In this propensity-weighted cohort, intraoperative dexmedetomidine after cord clamping did not reduce blood loss during cesarean delivery.