Meconium is dark greenish-black material present in the intestines of all newborns. A fetus, in response to stress during the birthing process, might expel the material into the surrounding amniotic fluid and breathe meconium into the lungs. The result is referred to as meconium aspiration syndrome. The presence of meconium in the intestines of newborns is normal but it is usually expelled once feeding begins. Nutritional choices are based on the severity of the consequences of meconium aspiration, and they include standard breast or formula bottle feedings or intravenous fluids.
Diagnosis and Symptoms
A diagnosis of suspected meconium aspiration is derived from evidence of meconium in the amniotic fluid at birth, severe respiratory problems and an abnormal chest x-ray. Amniotic fluid fills the sac that surrounds the fetus during development and ruptures or breaks during the birthing process. Newborns with bluish skin, or cyanosis, breathing rapidly with grunting sounds when exhaling and retractions of chest muscles when breathing are also suspected of meconium aspiration. Prevention of aspiration begins before delivery, and most newborns who aspirate survive without complications.
Risk Factors
Higher risks for meconium aspiration include prolonged labor, post-term birth, difficult delivery, breech presentation, maternal hypertension, maternal diabetes and decreased fetal oxygen while in the uterus. Additional potential predictors of aspiration such as uterine infections, heavy cigarette smokers, mothers with chronic respiratory or heart disorders, problems with the umbilical cord and poor fetal growth within the uterus are also considered factors. Meconium aspiration syndrome is rare in newborns at less than 34 weeks gestation.
Nutritional Delivery
A primary concern with meconium aspiration in newborns is the quantity of meconium and the effect on the respiratory system. The level of respiratory distress determines the method of nutritional delivery. Newborns with little or no distress, despite aspiration, are started on breast or infant formula bottle feedings with supplemental water and are monitored. Newborns with respiratory distress and an inability to nurse receive intravenous fluids for hydration and sufficient dextrose to avoid low blood sugar. Gradually, electrolytes such as sodium, chloride and potassium, protein, fats and vitamins are added to maintain adequate nutrition.
Treatment
Treatment for meconium aspiration includes establishing, clearing and maintaining a patent airway and transport to a special care nursery or neonatal intesive care unit. Meconium in the airways creates an inflammatory process with redness and swelling and increasing difficulty breathing. Meconium can block the smaller airways in the lungs, causing infections and areas to collapse. Additional treatments include antibiotics, radiant warmers, supplemental oxygen, ventilator management, nitric oxide, lung-bypass equipment and surfactant administration, based on the severity of symptoms.
