Magnesium sulphate versus lytic cocktail for eclampsia

Eclampsia, the occurrence of a seizure in association with pre-eclampsia, is a rare but serious complication of pregnancy. A number of different anticonvulsants have been used to control eclamptic fits and to prevent further seizures.

The objective of this review was to assess the effects of magnesium sulphate compared with lytic cocktail (usually chlorpromazine, promethazine and pethidine) when used for the care of women with eclampsia. Magnesium sulphate is compared with diazepam and with phenytoin in other Cochrane reviews.

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (July 2010) and the Cochrane Central Register of Trials (The Cochrane Library 2010, Issue 2).

Randomised trials comparing magnesium sulphate (intravenous or intramuscular administration) with lytic cocktail for women with a clinical diagnosis of eclampsia.

Two review authors (L Duley and D Chou) assessed trial quality and extracted data.

We included three small trials (total 397 women) of average quality in the review. Magnesium sulphate was associated with fewer maternal deaths (risk ratio (RR) 0.14, 95% confidence interval (CI) 0.03 to 0.59; 3 trials, 397 women) and was better at preventing further seizures (RR 0.06, 95% CI 0.03 to 0.12; 3 trials, 397 women) than lytic cocktail. Magnesium sulphate was also associated with less respiratory depression (RR 0.12, 95% CI 0.02 to 0.91; 2 trials, 198 women), less coma (RR 0.04, 95% CI 0.00 to 0.74; 1 trial, 108 women), and less pneumonia (RR 0.20, 95% CI 0.06 to 0.67; 2 trials, 307 women). There was no clear difference in the RR for any death of the baby (RR 0.35, 95% CI 0.05 to 2.38, random effects; 2 trials, 177 babies).

Magnesium sulphate, rather than lytic cocktail, for women with eclampsia reduces the RR of maternal death, of further seizures and of serious maternal morbidity (respiratory depression, coma, pneumonia). Magnesium sulphate is the anticonvulsant of choice for women with eclampsia; the use of lytic cocktail should be abandoned.