Amnioinfusions: Is it time to call it quits?

Amnioinfusion (AI) doesn't lower the risk of meconium aspiration syndrome (MAS), cesarean delivery, or other key complications in women in labor with thickly meconium-stained amniotic fluid, according to a international randomized trial involving nearly 2,000 patients presented at this year's SMFM meeting in Reno.

Investigators were primarily interested in finding out if AI for thickly meconium-stained amniotic fluid lowers perinatal death or moderate-to-severe MAS-or both. But they also wanted to know if it reduces cesarean section and other serious problems. They studied women with this complication who went into labor at 36 weeks' gestation or later and stratified them depending on whether variable fetal heart rate decelerations were present or not. They randomized the patients either to standard care or to AI. (AI consisted of a transcervical bolus of 800 mL of saline over a 40-minute period, after which the women were infused with 2 mL/minute to a maximum of 1,500 mL). Severity of MAS was based on clinical respiratory distress.

The researchers found that perinatal death, moderate or severe MAS, or both, occurred in 44 babies (4.5%) in the AI group and in 34 controls (3.4%) (RR = 1.3; 95% CI = 0.8–2.0). In addition, the AI group tended to have more cesarean deliveries.