Dexmedetomidine as a part of general anaesthesia for caesarean delivery in patients with pre-eclampsia: A randomised double-blinded trial

BACKGROUNDDuring general anaesthesia, endotracheal intubation of patients with pre-eclampsia causes stimulation of the sympathetic nervous system and catecholamine release, which may lead to maternal and neonatal complications.OBJECTIVETo attenuate both the stress response and the haemodynamic response to tracheal intubation in patients with pre-eclampsia.DESIGNA randomised, double-blind, controlled study.SETTINGSingle University Hospital.PATIENTSSixty patients aged 18 to 45 years with pre-eclampsia receiving general anaesthesia for caesarean section.INTERVENTIONSThe patients were randomly allocated to three groups. Groups D1and D2 received an infusion of dexmedetomidine 1gkg(-1) over the 10min before induction of general anaesthesia, then 0.4 and 0.6gkg(-1)h(-1) dexmedetomidine, respectively. Group C received equivalent volumes of 0.9% saline.MAIN OUTCOME MEASURESThe primary outcome was the effect of dexmedetomidine on mean arterial blood pressure measured before induction of general anaesthesia at 1 and 5min after intubation, and then every 5min until 10min after extubation. The secondary outcomes were blood glucose and serum cortisol (measured before induction of general anaesthesia, and at 1 and 5min after intubation), postoperative visual analogue pain scores, time to first request for analgesia, the total consumption of analgesia, Ramsay sedation score, maternal and placental vein blood serum levels of dexmedetomidine and neonatal Apgar score at 1 and 5min.RESULTSAt all assessment times, the mean arterial pressures were significantly lower in the dexmedetomidine groups than in the control group. Compared with group C, the heart rate was significantly lower in both groups D1 and D2. In group D2, the heart rate was lower than in group D1. Serum glucose and cortisol were significantly higher in the controls than in either group D1 or D2. Group D2 patients were significantly more sedated on arrival in the recovery room followed by D1. Time to first analgesia was significantly longer in groups D2 and D1 than in group C, and the visual analogue pain scores were significantly lower in groups D1 and D2 than in group C at 1, 2, 3 and 5h. Total morphine consumption was significantly lower in groups D1 and D2 than in the control group. There was no difference in Apgar scores across the three groups despite significantly higher dexmedetomidine concentrations in group D2 (both maternal and placental vein) than in group D1.CONCLUSIONAdministration of dexmedetomidine in doses 0.4 and 0.6gkg(-1)h(-1) was associated with haemodynamic and hormonal stability, without causing significant adverse neonatal outcome.TRIAL REGISTRATIONPan African Clinical Trial Registry (PACTR201706002303170), (www.pactr.org).