Epidural therapy for severe pregnancy induced hypertension to reduce morbidity and mortality in the mother and infants
What is the issue?
Pre-eclampsia is a serious pregnancy-related, multiorgan disorder which effects both mother and baby generally in the third trimester. High blood pressure and protein in the urine are early indications of pre-eclampsia. If severe, women can develop headache, visual disturbance, pain in the stomach or upper abdomen regions, nausea and vomiting. They are at high risk of seizures, haemolysis (breakdown of red blood cells) elevated liver enzymes and low platelets (HELLP) syndrome, oedema in the lungs, widespread activation of blood clotting, loss of vision, renal or liver failure and placental abruption where the placenta separates from the uterus. The leakage of fluid out of the blood vessels and into the surrounding tissues causes swelling, reduced volume of circulating blood and blood flow to vital organs. The baby is at risk of restricted growth, stillbirth, preterm birth or death around the time of birth or soon after. The common cause appears to be a decrease in the blood flow to the uterus and placenta.
Why is this important?
Women with severe pre-eclampsia are treated with drugs to lower their blood pressure, magnesium sulphate or other anticonvulsants to prevent seizures (eclampsia), and drugs to control blood clotting.
Extended epidural anaesthesia may have a role in reducing the risk of stroke or cerebral bleeding, kidney and liver failure with severe pre-eclampsia. This could give time for optimal planning of delivery so that outcomes are improved for the mother and her baby. Blood flow to the uterus and placenta may be increased so that birth outcomes are improved. Extended epidural analgesia has also been reported to be well-tolerated for up to one week. The purpose of this review was to evaluate the use of epidural therapy as a treatment modality for severe pre-eclampsia and to compare this therapy with other established treatments.
What evidence did we find?
We searched for evidence in July 2017 and identified one small randomised controlled study (involving 24 women) for inclusion in this review. The women were at 30 weeks of gestation or more, diagnosed with severe pre-eclampsia, and being cared for in an intensive care unit. They were randomly assigned to an epidural block plus their other medications or a drug to treat their high blood pressure plus their other medications. After six hours of treatment they all underwent a caesarean section.
The included study did not report on any of the important outcomes of interest in this review such as death of the mother, death of her baby (before or after being born), serious illness for the mother or her baby, the mother developing eclampsia or seizures, or side effects of the intervention.
The study authors did report difference in the infant Apgar scores between the two groups The study authors also reported a clear drop in the diastolic blood pressure in the epidural group compared to the other group. Systolic and mean blood pressures were similar in the two groups of women. However, the study did not report on any other mother or baby outcomes of interest in this review.
What does this mean?
There is not enough evidence from randomised controlled trials to evaluate the use of epidural therapy in severe pre-eclampsia to improve outcomes for the mother or her baby. High-quality trials are needed to evaluate the efficacy, safety and cost of epidural therapy in severe pre-eclampsia. Future studies could report on important outcomes such as those listed in this review.