Meconium Aspiration Syndrome (MAS)
Definition
Epidemiology
Clinical Features
Investigations
Complications
Treatment
Prevention
Source
Toronto Notes 2012
- 10-15% of all infants are meconium stained at birth
- Usually associated with fetal distress in utero or post-term infants
- Meconium is sterile but causes airway obstruction, chemical inflammation, and surfactant inactivation
Epidemiology
- -5% of meconium stained infants get MAS
Clinical Features
- Respiratory distress
- Small airway obstruction, chemical pneumonitis --> tachypnoea, barrel chest with audible crackles
Investigations
- CXR: hyperinflation, streaky atelectasis, patchy and coarse infiltrates (10-20% have pneumothorax)
Complications
- Hypoxemia, hypercapnea, acidosis, PPHN, pneumothorax, pneumomediastinum, pneumonia, sepsis, respiratory failure, death
Treatment
- Supportive (maintain adequate oxygenation)
- Surfactant replacement
Prevention
- Careful monitoring
- At birth: intubate and suction below cords if infant is depressed (Note: presence of meconium staining alone is NOT an indication for tracheal suctioning. If the infant is vigorous, intubation, and suctioning of lower airway is unnecessary)
Source
Toronto Notes 2012