4. OBJECTIVES
GENERAL OBJECTIVES
At the end of this inservice education programme the participants will be able to explain about
Meconium Aspiration Syndrome.
SPECIFIC OBJECTIVES
At the end of this inservice education programme the participants will be able to :
- Introduce meconium
- Define meconium aspiration syndrome
- State its incidence
- Enlist its causes and risk factors
- Explain its pathophyisiology
- Enlist its clinical features
- State the diagnostic evaluations
- Explain the treatment measures and the nursing management
- Explain the preventive measures
- State the prognosis and complications
6. CONTENTS
Introduction of meconium
Defination of MAS
Incidence
Etiology
Risk Factors
Pathophysioloy
Clinical Features
Diagnostic Evaluation
Treatment And Management
Nursing management
Prevention
Prognosis
Complication
7. Introduction of Meconium
Meconium is thick , pasty, greenish- black
substance that is present in the fetal bowel,
which is first stool passed by new born.
Meconium is typically passed for 2-3 days after
birth.
Sometimes, the fetus passes the meconium
while it is still in the womb.
Meconium consists of bile, intestinal secretions,
amniotic fluid, lanugo, mucus.
8.
9. Defination
Meconium Aspiration Syndrome is a serious medical
condition where neonates born to mother with thick or
thin meconium stained liqor aspirate the meconium into
the lungs and develop respiratory distress.
10. Incidence
It occurs approximately in 8-15% of live births.
Approximately 5% of neonates born through meconium
stained amniotic fluid develop MAS
OF MEC stained infants:
30 % depressed at birth
10 % meconium aspiration syndrome (range 2-36 %)
OF infants with MEC aspiration syndrome
17 % deliver through thin meconium (range 7-35 %)
35 % need mechanical ventilation (range 25-60 %)
12 % die (range 5-37 %)
Frequency of Mec stained amniotic fluid = 10-25%
11. Etiology Or Causes
Hypoxia in distressed baby
Meconium Stained Liqor
Uterine Infections
Difficulty during labour process
14. Risk Factors
Post maturity
Prolonged and obstructed delivery
Maternal hypertension or diabetes mellitus
Placental dysfunction and infection like chorioamnitis
Intra uterine growth retardation
Umbilical cord complications
Ageing of placenta
Intrauterine fetal hypoxia
Maternal heavy smoking
Oligohydraminous
Pre eclampsia and eclampsia
15. PATHOPHYSIOLOGY
A.PASSAGE Of MECONIUM IN UTERO:MSAFeconium stained aminiotic fluid)may result from of
post – term fetus with rising motilin levels and normal gastrointestinal function ,vagal
stimulation produced by cord or head compression ,or in utero fetal stress.
B.ASPIRATION OF MECONIUM:In the presence of fetal stress ,gasping by the fetus can result
in aspiration of meconium before,during or immediately following delivery.Severe MAS
appears to be caused by pathologic intrauterine processes ,primarily chronic hypoxia
,acidosis ,and infection .
C.EFFECTS OF MECONIUM ASPIRATION: When aspirated into the lungs ,meconium may
stimulate the release of cytokines and vasoactive substances that result in cardiovascular
and inflammatory responses in the fetus and newborn .Meconium its self ,or the resultant
chemical pneumonitis,mechanically obstructs the small airways,causes atelectasis and a
“ball-valve” effect with resultant air trapping and possible air leak.Aspirated meconium
leads to vasospasm,hypertrophy of the pulmonary arterial musculature,and pulmonary
hypertension that lead to extra pulmonary right- to –left shunting through the ductus
arteriosus or the foramen ovale and results in worsened ventilation –
perfusion(v/Q)mismatch ,leading to severe arterial hypoxemia .Aspirated meconium also
inhibits surfactant function.
18. CLINICAL FEATURES
Difficulty in breathing
Cyanosis
End expiratory grunting
Greenish appearance of amniotic fluid
Intercoastal retraction
Tachypnea, flaring
Barrel chest(increased anteroposterior diameter due to presence of air
trapping
Auscultated rales and rhonchi (in some cases)
Yellow green staining of finger nail,umbilical cord and skin may be observed
Grunting
Arterial PO2 may be low
If hypoxia metabolic acidosis is present
Pulmonary edema
19. DIAGNOSTIC EVALUATION
Before birth the fetal monitor may show bradycardia
During delivery or at birth ,meconium can be seen in the amniotic fluid
and on the infant.
Low APGAR score after birth
Physical examination:lungs sound (coarse, crackly sound)
Blood gas analysis :low blood acidity ,decreased oxygen and increased
carbon dioxide.
Chest x-ray may show patchy or streaky areas in lungs .
Urine colour may appear dark brown.
20.
21. MANAGEMENT OF INFANT DELIVERED THROUGH
MECONIUM-STAINED FLUID
A.INITIAL ASSESSMENT-At a delivery complicated by MSAF
determine whether the infant is vigorous,demonstrated by:
heart rate more than 100 beats/min
spontaneous respiration
good tone(spontaneous movement or some degree of flexion).
If the infant appears vigorous,routine care should be
provided,regardless of the consistency of the meconium.
Initiate suctioning as soon as the baby is delivered.
If the baby has continuous breathing problem, continue suctioning
using laryngoscope
22. Continuation…
-The infant should be placed on a radiant warmer and given free flow
oxygen.
-Delay drying and stimulation and postpone emptying of any gastric contents
until the infant has stabilized.
-Intubation should be done under direct laryngoscopy before inspiratory efforts
have been initiated .
-Avoid positive pressure ventilation if possible until tracheal suctioning is
accomplished.
Do NOT perform the following harmful techniques in an attempt to
prevent aspiration of meconium-stained amniotic fluid:
Squeezing the chest of the baby
Inserting a finger into the mouth of the baby
25. MANAGEMENT OF MAS
A.Observation:Baby born with meconium stained liqor requires close
observation for the assessment of respiratory distress.
A chest radiograph may be helpful to determine signs of respiratory
distress.
Monitoring of oxygen during this period helps to assess severity of
infant’s condition and avoids hypoxemia.
B.Routine care: neutral thermal environment should be maintained with
minimum of tactile stimulation.
Blood glucose and calcium level should be monitored and corrected if
necessary.
Fluid should be restricted as far as possible to prevent cerebral and
pulmonary edema.
26. Contd….
Special therapy for hypotension and poor cardiac output is
required including cardiotonic medicines such as dopamine.
Circulatory support with normal saline or packed redblood
cells should be provided in patients with marginal
oxygenation.(Hb above 15g and haematocrit above 40% should
be maintained)
Renal function should be continuously monitored.
C.Oxygen therapy:Hypoxia should be managed by increasing
inspired oxygen concerntration and monitoring of blood gases
and PH.
D.Asissted Ventilation:
1. Continuous Positive Airway Pressure(CPAP)
28. Guidelines for management of MAS
The American Academy of Pediatrics Neonatal Resuscitation Program
Steering Committee and the American Heart Association’s current
guidelines are as follows:
If the baby is not vigorous
Use direct laryngoscopy, intubate and suction the trachea
immediately after delivery.
Suction for no longer than 5 seconds.
If no meconium is retrieved, do not repeat intubation and suction.
If meconium is retrieved and no bradycardia is present, reintubate
and suction.
If the heart rate is low, administer positive pressure ventilation and
consider suctioning again later.
29. If the baby is vigorous
Do not electively intubate.
Clear secretions and meconium from the mouth and nose with a bulb
syringe or a large-bore suction catheter.
30. CONTD……….
• In both cases, the remainder of the initial
resuscitation steps should ensure,
including drying, stimulating, repositioning
and administering oxygen as necessary.
31. NURSING INTERVENTIONS
• During labor, continuously monitor the fetus for signs and symptoms of distress.
• Immediately inspect any fluid passed with rupture of the membrane.
• Assist with immediate endotracheal suctioning before the first breaths, as
indicated.
• Monitor lung status closely, including breath sounds and respiratory rate and
character.
• Frequently assess the neonate’s vital signs.
• Administer oxygen and respiratory support as ordered.
Warm and humidify oxygen
Institute measures to maintain a neutral thermal environment
• Provide the family with emotional support and guidance.
32. Interventions for thermo regulation
Place warm blankets on scales, x-ray plates, or other surfaces in contact
with the baby
Warm blankets and clothing before use
Preheat incubators, radiant warmers, heat shield
Maintain room temperature at levels adequate to provide a safe thermal
environment for neonate
33. Prevention Of MAS
ANTEPARTUM PERIOD
Women should be carefully monitored during pregnancy and should be
encouraged for hospital delivery.
INTRAPARTUM PERIOD
Fetal heart rate should be monitored every half an hourly to determined
the sign of fetal distress
Babies born to mother with meconium stained liqor should have
oropharyngeal suction before the delivery of shoulder.
AMNIOINFUSION
TIMING AND MODE OF DELIVERY
Pregnancy that crosses the date should be induced as early as 41weeks
which helps to prevent MAS by avoiding passage of meconium .Delivery
mode does not appear to significantly impact the risk of aspiration .
34. PROGNOSIS
-Recovery usually occurs within 3-5days but tachypnea may persist for a
longer period
-Prognosis depends on frequent accompanying of asphyxia insult rather
than severity of pulmonary disease
-Mortality rate is as high as 50%if PPHN(Persistant Pulmonary Hypertension
of neonates) is present.
-Residual problem is rare but cough, wheezing and persistent hyperinflation
may extend upto 5-10years.
-50%of MAS cases require mechanical ventilation out of which 60-
70%neonate survive.
-Its mortality rate is 3-5%.
35. complication
Pneumothorax(15-33%)
Massive atelectasis
Obstructive emphysema leading to pneumothorax
Pneumopericardium
Pneumomediastinum(15-33%)
Persistent pulmonary hypertension in neonates ( one third of cases)
If prolonged assisted ventilation , bronchopulmonary dysplasia
Meconium aspiration pneumonia 5%.
36. Other Things to Watch For
Hypoxia
Acidosis
Hypoglycemia
Hypocalcemia
End-organ damage due to perinatal
asphyxia