Amnioinfusion doesn’t prevent meconium aspiration
|
|
Infusion of fluid into the amniotic cavity (amnioinfusion) during labor in women with thick meconium staining of the amniotic fluid does not reduce the risk of meconium aspiration syndrome or death of the fetus or infant, new research shows. This finding held true whether or not slowing of the fetal heart rate was detected.
Meconium aspiration syndrome occurs in when the meconium, the first feces of the newborn, is inhaled either in the uterus or just after delivery. The possibility of inhaling meconium occurs in about 5 to10 percent of births. It typically occurs when the fetus is stressed during labor and is a leading cause of serious illness or death in the newborn.
The process of amnioinfusion involves infusing a neutral water-based solution into the amniotic cavity and was first introduced to treat low amniotic fluid (oligohydramnios) in the early 1980s, lead author Dr. William D. Fraser told, (University of Montreal). Over time, however, the procedure also became used to prevent meconium aspiration syndrome.
“A number of small, single-center studies have been conducted and most of them did not show a benefit for amnioinfusion in preventing meconium aspiration syndrome,” Fraser noted. “However, when the studies were grouped together…there was evidence of a reduction in risk.”
“Our study is the first large, adequately powered, multicenter trial to investigate this topic, and we found no evidence that amnioinfusion was useful for this (condition),” Fraser said.
The study, which is reported in The New England Journal of Medicine, involved almost 2,000 pregnant women who had thick meconium staining of the amniotic fluid. The women were randomly assigned to receive amnioinfusion or standard care. All of the women were in labor and had been pregnant at least 36 weeks.
The rate of death or moderate-to-severe meconium aspiration syndrome in amnioinfusion group was 4.5 percent, not significantly different than the 3.5 percent rate seen in the standard-care group. The rates of c-section in the amnioinfusion and standard-care groups were also similar, at 31.8 percent and 29.0 percent, respectively.
As noted, no benefit for amnioinfusion was seen when the women were classed according to the presence or absence of irregular fetal heart rate.
While not effective, amnioinfusion did not appear to be harmful either, Fraser noted. No adverse effects were specifically linked to the procedure.
Fraser said he believes the current findings largely settle the issue of whether amnioinfusion is useful in preventing meconium aspiration syndrome. However, he said there is still a question of whether it might be useful in resource-poor areas that lack fetal heart monitoring. “Also, there is a need for studies that address the effect of amnioinfusion on clinically significant fetal heart rate abnormalities,” he added.
SOURCE: The New England Journal of Medicine, September 1, 2005.
Print Version
Tell-a-Friend comments powered by Disqus
