Sindroma Aspirasi Mekonium

Meconium Aspiration Syndrome( MAS )

Bambang MulyawanFK-UMM

Pendahuluan

• MAS merupakan masalah kegawatan yg sering dijumpai di ruang bersalin ( hipoksiahipoksia intrauterine aspirasi pneumoni BBL )

• Biasanya pd bayi cukup bulan dan lebih bulan ( : Kecil untuk Masa Kehamilan / KMK )

• Waspada : jika BBL lahir dg cairan ketuban campur mekonium dg gejala RDS

Patogenesis dan patofisiologi

• Stress intrauterin mekonium in-utero ke dlm cairan ketuban, terhisap janin ketika inspirasi o.k hipoksi dan stimulasi vagal fetal distres / sebelum persa-linan

• Mekanisme keluarnya mekonium in-utero masih belum jelas

Patogenesis dan patofisiologi ( lanj.)

• BBL dg cairan ketuban mekonial asfiksia antepartum atau intrapartum obstruksi jalan nafas, turunnya kapasitas paru, pe> expiratory large airway resistancxe

• Obstruksi total : atelektasis. Partial : trapping udara dan hiperekspansi alveolar

• Mekonium pd alveolar me< fungsi surfaktan kolaps RDS

Patogen . . . . . ( lanj. )

• Hipoksia intrauterin aspirasi mekonium obstruksi mekanik / keradangan kimiawi air trapping / atelektasis ventilasi tidak seimbang / intrapulmonal shunting kebocoran udara hipoksemia asidosis sirkulasi fetal persistent

SINDROM ASPIRASI MEKONIUM (SAM)

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Hipoksia janin

Mekonium keluar & janin gasping

Cairan amnion yang terkontaminasi mekonium terhirup ke larings dan trakhea

Mekonium masuk saluran napas lebih kecil dan alveolus

Kerusakan paru

Pembersihan sal. napas tidak adekuat

Kerusakan paru

• Mekonium mengandung enzim merusak epitel bronkus, bronkiolus dan alveolus

• Mekonium menyumbat sal. napas secara total/parsial beberapa bagian paru kolaps, bagian paru lain hiperinflasi

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What Is Meconium?• Odorless, thick, blackish green material• First seen during the third month of gestation• Accumulation of desquamated cells from GI

tract, skin, lanugo, fatty material from the vernix, amniotic fluid

Manifestasi klinis

• Bervariasi : tergantung keparahan serangan hipoksik dan jumlah viskositas mekonium teraspirasi

• Sering pada gestasi post matur : warna meko. pd kuku, rambut, tali pusat

• Gejala RDS ( takipnea, NCH, retraksi interkostal, diameter AP dada >, sianosis

• Pada gejala MAS lambat : distres nafas awal ringan. Semakin parah bbrp jam : atelektasis dan pneumonitis kimia

• Auskultasi : vesikular lemag, ronki/rales, wheezing/mengi

Pemeriksaan radiologis

• Foto polos dada : infiltrat kasar menyebar pd kedua lap.paru, dapat disertai pneumotoraks, atelektasis, emfisema

Chest X-Ray

• Hyperinflation• Coarse, patchy densities

representing scattered areas of atelectasis and consolidation mixed with air trapping

Faktor predisposisi

• Insufisiensi plasenta, hipertensi, oligohidramnion, ibu kecanduan ( rokok, kokain), infeksi (chorio-amnionitis) hipoksia, manajemen jalan nafas tidak adekuat, defisiensi surfaktan, hipertensi pulmonal

Risk Factors for Meconium Passage

• Postterm pregnancy• Preeclampsia-eclampsia• Maternal hypertension• Maternal diabetes mellitus• Abnormal fetal heart rate• IUGR• Abnormal biophysical

profile• Oligohydramnios• Maternal heavy smoking

Infant ActiveInfant ActiveInfant DepressedInfant Depressed

Intrapartum suctioning of mouth, Intrapartum suctioning of mouth, nose, pharynxnose, pharynx

Intubate and suction Intubate and suction tracheatrachea

Other resuscitation as indicatedOther resuscitation as indicated

ObserveObserve

Meconium in Amniotic FluidMeconium in Amniotic Fluid

Langkah diagnostik

• Riwayat : PJT ( pertumbuhan janin terhambat ), kesulitan persalinan / gawat janin, persalinan dg air ketuban mekonial, asfiksia berat

• Pemerksaan fisik : cair ketuban mekonial/ bayi diliputi mekonium, tl pusat/kulit bayi warna hijau, asfiksia berat bbrp jam gangguan nafas/RDS, td bayi lebih bulan

• Foto toraks : AP dan Lateral• Laboratorium: Hb, Ht, darah tepi, kultur• Analisa Gas Darah : hipoksemia, asidemia : asidosis metabolik,

respiratorik,/kombinasi

Diagnosis

• Cukup/lebih bulan, jarang sekali kurang bulan• Cairan amnion terkontaminasi mekonium• Mekonium tampak/dapat dihisap dari saluran napas atas

(bantuan laringoskop)• Kulit bayi diwarnai mekonium• Sesak napas• Foto toraks : hiperinflasi paru disertai banyak daerah

paru yang kolaps

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Pencegahan

Pembersihan saluran napas atas sebelum bayi bernapas saat lahir

–Penghisapan saluran napas sebelum bahu dilahirkan

–Penghisapan saluran napas (larings dan trakea) secara langsung dengan bantuan laringoskop

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penatalaksanaan

• Prevensi slm periode prenatal, antenatal, tindaka tepat slm intrapartum

• Diagram Alur Resusitasi Neonatus

Pengobatan / terapi

• Suportif : oksigen, suhu lingkungan, perawatan pernafasan, kadar gas darah arteri, terapi surfaktan, ventilasi mekanik, cairan infus glukosa 10%

• Antibiotik spektrum luas• Tindakan bedah :pd pneumotoraks, pneumomediastinum,

empisema subkutan : pungsi toraks, drainase

Perjalanan PenyakitPerjalanan Penyakit

SAM : sesak napas sejak lahirSAM : sesak napas sejak lahir

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SAM ringan : SAM ringan : membaik membaik secara bertahap secara bertahap dalam beberapa dalam beberapa hari – beberapa hari – beberapa minggu minggu

Memburuk Memburuk secara secara progresif progresif tidak tidak tertolong tertolong

Tertolong Tertolong kerusakan paru kerusakan paru perlu waktu perlu waktu lama untuk lama untuk sembuh sembuh sempurna sempurna

SAM SAM berat berat

Komplikasi

1. Pneumotoraks / pneumomediastinum

2. Kerusakan akibat hipoksia pada organ lain

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Pemantauan/Monitoring

• Tumbuh kembang pd bayi yg selamat, hidup tanpa komplikasi (survival intact) baik

• Pada bayi dg komplikasi hipoksi serebri, gagal ginjal, efek tosik O2, epilepsi, palsi serebral gangguan tumbuh kembang

Pathogenesis

• Meconium stained amniotic fluid (MSAF) occurs in 10-25% of all deliveries

• Meconium aspiration syndrome (MAS) occurs in 2-5% of infants born through MSAF

Pathogenesis

• Risk increases with gestational age

• Before 37 weeks the risk of MSAF is 2%

• After 44 weeks the risk of MSAF is 44%

Pathogenesis• Cause of MSAF is unclear• Studies have not shown that it is synonymous

with fetal asphyxia• MSAF with fetal bradycardia does correlate

with increased perinatal morbidity

Pathogenesis• Normal fetuses have respiratory movements

in utero• If a fetus is hypoxemic, respirations briefly

stop• With prolonged hypoxia, apnea turns into

gasping

Pathogenesis

• Gasping meconium stained fluid can lead to mechanical obstruction of the airways

• Yeomans et al showed that cord arterial pH is lower in infants with meconium in their trachea at delivery which suggests in utero stress

Pathogenesis• If meconium is not suctioned out of the airway at

delivery, it can migrate to the periphery of the lung• Small airway obstruction produces patchy atelectasis

and hyperinflation• This leads to a chemical pneumonitis and interstitial

edema• Alveoli are infiltrated with debris, neutrophils, and

necrosed epithelial cells

Pathogenesis• Pulmonary vascular resistance can be

increased by increased vascular smooth muscle in the normally nonmuscularized intra-acinar arterioles

• Pulmonary hypertension frequently complicates MAS

Pathogenesis• Endogenous surfactant can be inactivated by

meconium and the chemical pneumonitis • This may worsen the severity of the illness

Clinical Manifestations

• Often postmature• Meconium staining of skin

and nails• Distressed• Barrel chest from

hyperinflation• Crackles in lungs

Clinical Manifestations• Pneumothorax is a common complication• Symptoms progress over 12 to 24 hours as the

meconium migrates• Phagocytes remove the meconium which

takes days to weeks

Delivery Room Therapy• Wiswell and his colleagues performed a

multicenter study on delivery room management of the apparently vigorous meconium stained neonate

• Routine suctioning of the trachea no better than expectant management

Therapy: Wiswell Cont.• Oropharyngeal suctioning with a bulb suction before

the delivery of an infants shoulders is still recommended

• Amnioinfusion did not help prevent MAS• NRP recommends tracheal suction of the

nonvigorous infant born• through meconium

Treatment• Oxygen• Mechanical ventilation if necessary• Keep in mind that PPHN may be a component

and treat appropriately– iNO– ECMO

Treatment• Surfactant– Cochran review showed it may reduce the severity of

respiratory illness and decrease need for ECMO

• Antibiotics– Controversial: no studies have shown a role of infection in

MAS– Difficult to distinguish infectious pneumonia from MAS

Treatment

• Steroids– Prolongs the course

of MAS by increasing the time to wean to room air

Outcome• Infants with MAS do very well• Overall mortality of infants with MSAF is

0.15%• Infants with MAS on ECMO have a mortality

range of 0-5% depending on the institution