Download RT 256 MAS

Meconium Aspiration
Syndrome
RT 256
Meconium
 Material that collects in the intestine of the fetus
 Intestinal tract secretions
 Amniotic fluid
 Pulmonary fetal fluid
 Intrauterine debris
 Forms the first stools of the newborn
 Thick and sticky, highly viscous
 Green to black in color
Aspiration of Meconium
1. Physical presence in the
airways
2. Chemical pneumonitis
3. Hypoxia induced pulmonary
arterial vasoconstriction and
vasospasm
Physical
presence in
the airways
leads to:
•
•
•
•
Upper airway
obstruction
Migration
past glottis
Penetration
into smaller
airways
Ball-valve
effect –
alveolar
rupture
 Acute inflammatory reaction
Chemical
Pneumonitis
 Edema
 Excessive bronchial secretions
 Alveolar consolidation
 Promotes the growth of bacteria
 Decreases pulmonary surfactant
production
 Hypoxia induced pulmonary
Hypoxemia
arterial vasoconstriction and
vasospasm
 Shunts blood right to left through
the ductous arterious and
foramen ovale
 Intrapulmonary shunting
 Pulmonary hypoperfusion
Etiology
 10% of births
 High risk for MAS include
 Post-term
 Small for gestational age
 Breech presentation
 Mother with toxemia, hypertension, or obesity
 Cause of meconium passage, consistency, and timing
Meconium passage
1. A PHYSIOLOGIC MATURATION
EVENT
2. RESPONSE TO ACUTE
HYPOXIC EVENTS OCCURRING
LATE IN PREGNANCY
3. RESPONSE TO CHRONIC
INTRAUTERINE HYPOXIA
Presentation
 Amniotic fluid examined
 Meconium staining of skin, nails, umbilical cord
 Manifestations of Respiratory Distress:
 Barrel chest
 Breath sounds – rhonchi, crackles, wheezing
 Retractions
 Cyanosis
 Increased respiratory rate
 Increased heart rate
Management
 PREVENTION!
 Suctioning during delivery (not current NRP guideline)
 Current NRP guidelines for meconium:

Vigorous vs Not Vigorous
Strong respiratory efforts
 Good muscle tone
 Heart rate >100beats/min



Intubate and suction with ETT
Do NOT ventilate until all meconium is cleared
 Oxygen Therapy
 Support ventilation as required
 Medications