MAS Flashcards
What triggers meconium release in Meconium Aspiration Syndrome?
Hypoxia stimulates the vagal reflex, relaxing the rectal sphincter and releasing meconium.
When can meconium be aspirated?
In utero or with the first breath.
What are the three main ways meconium causes respiratory distress?
1) Causes inflammation of bronchioles as a foreign substance, 2) Blocks small bronchioles by mechanical plugging, 3) Decreases surfactant production through lung trauma.
What complications can arise from Meconium Aspiration Syndrome?
Hypoxemia, carbon dioxide retention, intrapulmonary and extrapulmonary shunting, secondary infection leading to pneumonia.
What are key assessment findings for Meconium Aspiration Syndrome?
Low Apgar score, tachypnea, retractions, cyanosis, and meconium-stained amniotic fluid.
How is suctioning performed to avoid meconium aspiration at birth?
Suction with a bulb syringe or catheter while at the perineum before the birth of the shoulders.
What should be done if there is severe meconium staining?
Intubate and suction the trachea and bronchi.
Why should oxygen not be administered under pressure before suctioning?
Because it could push meconium deeper into the lungs.
What symptoms appear after initiation of respirations in Meconium Aspiration Syndrome?
Tachypnea, coarse bronchial sounds, and retractions due to air trapping.
What physical sign may be present due to air trapping in Meconium Aspiration Syndrome?
Enlargement of the anteroposterior diameter of the chest (barrel chest).
What do blood gases show in Meconium Aspiration Syndrome?
Poor gas exchange: decreased PO2 and increased PCO2.
What does a chest x-ray show in Meconium Aspiration Syndrome?
Bilateral coarse infiltrates in the lungs with areas of hyperaeration, creating a honeycomb effect.
What happens to the diaphragm in Meconium Aspiration Syndrome?
It is pushed downward by overexpanded lungs.
What is the role of amnioinfusion in Meconium Aspiration Syndrome management?
It dilutes the amount of meconium in the amniotic fluid.
What is the delivery method often used to reduce risks in Meconium Aspiration Syndrome?
Cesarean birth.
What therapeutic interventions are used after birth in Meconium Aspiration Syndrome?
Tracheal suction, oxygen administration, assisted ventilation, antibiotics, and surfactant therapy.
Why is high inspiratory pressure needed in Meconium Aspiration Syndrome?
Due to poor lung compliance.
What complications can high inspiratory pressures cause?
Pneumothorax or pneumomediastinum.
What signs should be watched for in Meconium Aspiration Syndrome?
Air trapping, pneumothorax, signs of heart failure (increased heart rate or respiratory distress).
How does increased pulmonary resistance affect circulation in Meconium Aspiration Syndrome?
The ductus arteriosus may remain open, causing blood to shunt from the pulmonary artery to the aorta, compromising cardiac efficiency and increasing hypoxia.
What environmental control is important in managing Meconium Aspiration Syndrome?
Maintaining a temperature-neutral environment.
What respiratory therapies help clear meconium remnants from the lungs?
Clapping and vibration techniques.
When is ECMO used in Meconium Aspiration Syndrome?
To ensure adequate oxygenation when conventional methods are insufficient.
What is the general prognosis for Meconium Aspiration Syndrome?
Symptoms usually fade within a week with no long-term effects.
