Meconium aspiration syndrome

Meconium aspiration syndrome (MAS) is defined as respiratory distress in the newborn due to the presence of meconium in the trachea.

Infants born through meconium-stained amniotic fluid are at risk of developing meconium aspiration syndrome, particularly in the presence of maternal and fetal risk factors. Post-maturity is a strong fetal risk factor; signs include green/yellow-coloured skin; long, stained nails; and dry, scaling skin.

Soon after birth, infants present with respiratory distress (tachypnoea, chest retractions, and hypoxia). Some may be asymptomatic and apparently vigorous at birth, and develop severe respiratory distress hours later.

Diagnosis is confirmed by chest x-ray.

Management is largely supportive. Infants should be monitored closely to ensure adequate oxygenation and ventilation.

In the presence of persistent pulmonary hypertension, inhaled nitric oxide and extracorporeal membrane oxygenation therapy may be required.

Meconium aspiration syndrome (MAS) is defined as respiratory distress in the newborn due to the presence of meconium in the trachea. It occurs exclusively in the immediate neonatal period.[1]Rossi EM, Philipson EH, Williams TG, et al. Meconium aspiration syndrome: intrapartum and neonatal attributes. Am J Obstet Gynecol. 1989 Nov;161(5):1106-10. http://www.ncbi.nlm.nih.gov/pubmed/2589429?tool=bestpractice.com It also covers respiratory distress in an infant, born through meconium-stained amniotic fluid, that cannot be explained otherwise.[2]Fanaroff AA. Meconium aspiration syndrome: historical aspects. J Perinatol. 2008 Dec;28(suppl 3):S3-7. https://www.nature.com/articles/jp2008162 http://www.ncbi.nlm.nih.gov/pubmed/19057607?tool=bestpractice.com