The Collaborative Randomised Amnioinfusion for Meconium Project (CRAMP): 2. Zimbabwe

Abstract

Objective: To evaluate transcervical amnioinfusion for meconium stained amniotic fluid during labour.

Design: Multicentre randomised controlled trial.

Setting: A large urban academic hospital. Electronic fetal heart rate monitoring was not used.

Participants: Women in labour at term with moderate or thick meconium staining of the amniotic fluid.

Interventions: Transcervical amnioinfusion of 500 mL saline over 30 minutes, then 500 mL at 30 drops per minute. The control group received routine care. Blinding of the intervention was not possible.

Main outcome measures: Caesarean section, meconium aspiration syndrome and perinatal mortality.

Results: There was no difference in risk for caesarean section in the two groups (amnioinfusion 9.5% vs control 12.3%; RR 0.84, 95% CI 0.53-1.32). Meconium aspiration syndrome was significantly less frequent in the amnioinfusion group (3.1% vs 12.8%; RR 0.24, 95% CI 0.12-0.48), and there was a trend towards fewer perinatal deaths (1.2% vs 3.6%; RR 0.34, 95% CI 0.11-1.06).

Conclusions: Amnioinfusion is technically feasible in a developing country situation with limited intrapartum facilities. In this study amnioinfusion for meconium stained amniotic fluid was associated with striking improvements in perinatal outcome.

PIP: The presence of meconium in the amniotic fluid is associated with increased perinatal morbidity and mortality. Saline amnioinfusion during labor has been shown, in several clinical trials, to reduce the incidence of cesarean section and meconium aspiration syndrome. A randomized controlled trial conducted at Harare Maternity Hospital in Zimbabwe sought to confirm the benefits of amnioinfusion for meconium-stained amniotic fluid during labor for perinatal outcome. In the intervention group (n = 325), 500 ml of saline was transcervically amnioinfused over a 30-minute period, followed by 500 ml at 30 drops per minute for the duration of labor. The control group (n = 336) received routine obstetric care. The cesarean section rate was 9.5% in the intervention group and 12.3% in the control group (relative risk (RR), 0.84; 95% confidence interval (CI), 0.53-1.32). Meconium aspiration syndrome was significantly less frequent in the amnioinfusion group (3.1%) than the control group (12.8%) (RR, 0.24; 95% CI, 0.12-0.48). The perinatal death rate was 1.2% in the amnioinfusion group and 3.6% among controls (RR, 0.34; 95% CI, 0.11-1.06). Also recorded in the amnioinfusion group were significant reductions in the following perinatal morbidity measures: 5-minute Apgar score below 7, neonatal intensive care admissions, neonatal ventilation, and hypoxic ischemic encephalopathy. The striking improvements in perinatal outcome recorded among women in the amnioinfusion group suggest the feasibility of more widespread use of this simple procedure in developing country settings without routine electronic fetal monitoring facilities.