รองศาสตราจารย์ นายแพทย์ อติวุทธ กมุทมาศ Birth asphyxia รองศาสตราจารย์ นายแพทย์ อติวุทธ กมุทมาศ

Asphyxia APGAR score at 1 minute < 7 Interruption in oxygen delivery to the fetus • Hypoxia • Hypercapnia Birth asphyxia เป็นภาวะที่ทารกแรกเกิดไม่สามารถปรับตัวในการเปลี่ยนแปลงทางระบบหายใจและการไหลเวียนเลือดจากครรภ์มารดา มาสู่ภาวะแวดล้อมภายนอก

Neonatal Evaluation and Resuscitation APGAR Scoring A Appearance P Pulse G Grimace A Activity R Respirations Take the APGAR score at one minute and five minutes.

APGAR Score APGAR Score: Appearance The skin of a newborn should be pink. Assess the newborn’s skin color and score as follows: Entire body blue or pale - 0 points Blue hands and feet - 1 point Entire body pink - 2 points APGAR Score: Pulse The pulse of a newborn should be greater than 100 beats per minute. Assess the newborn’s brachial pulse or use a stethoscope and score as follows: Pulse absent - 0 points Pulse less than 100 - 1 point Pulse greater than 100 - 2 points APGAR Score: Activity A newborn should exhibit active flexion and extension of the extremities. Assess the newborn’s activity and score as follows: No extremity movement - 0 points Minimal activity - 1 point Strong activity - 2 points APGAR Score: Respirations A newborn should breathe between 30 and 60 times a minute or exhibit a strong cry. Assess the newborn’s breathing and score as follows: No respiratory effort - 0 points Slow (<30/minute), irregular, or weak cry - 1 point Normal respirations or strong cry - 2 points APGAR Score At the conclusion of the APGAR score, add the numbers together and consider the following: 7-10 points - The newborn should be active and vigorous. Provide routine care. 4-6 points - The newborn is moderately depressed. Provide stimulation and oxygen. 0-3 points - The newborn is severely depressed and requires extensive resuscitation.

Apgar Score Total Score = 10 score 7-10 normal score 5-6 mild birth asphyxia score 3-4 moderate birth asphyxia score 0-2 severe birth asphyxia

Causes of Neonatal Mortality Source: WHO 2001 estimates (based on data collected around 1999)

Etiology Birth asphyxia in undeveloped countries 10% of newborns suffer mild to moderate birth asphyxia 1% of newborns suffer severe birth asphyxia

Risk factors Antepartum : Maternal diabetes post-term gestation Pregnancy induced hypertension multiple gestation Chronic hypertension size-dates discrepancy Previous Rh sensitization maternal drug abuse Previous stillbirth maternal age >35 or<16 Bleeding in second or third trimester no prenatal care Maternal infection Polyhydramnios or oligohydramnios

Risk factors Intrapartum : Elective or emergency c/s Precipitous labour, prolonged labour Prolonged second stage of labour Premature labour Abnormal presentation Rupture of membranes > 24 hours Foul-smelling amniotic fluid Non reassuring fetal heart rate patterns Use of general anesthesia Prolapsed cord

Assessment Fetal heart rate slows Electronic fetal monitoring • persistent late deceleration of any magnitude • persistent severe variable deceleration • prolonged bradycardia • decreased or absent beat-to-beat variability Thick meconium-stained amniotic fluid Fetal scalp blood analysis show pH less than 7.2

Effects of Asphyxia Central nervous system • infarction, intracranial hemorrhage, cerebral edema, seizure, hypoxic- ischemic encephalopathy Cardiovascular • bradycardia, ventricular hypertrophy, arrhythmia, hypotension, myocardial ischemia

Effects of Asphyxia Respiratory system • apnea, respiratory distress syndrome cyanosis KUB • acute tubular necrosis, bladder paralysis Gastrointestinal tract • necrotizing enterocolitis , stress ulcer

Effects of Asphyxia Hematology • Disseminated intravascular coagulation Metabolic • hypoglycemia, hyperglycemia, hypocalcemia, hyponatremia Integument • subcutaneous fat necrosis

Neonatal Resuscitation Administer blow-by oxygen if the newborn displays: Cyanosis of the skin Spontaneous and adequate breathing Heart rate above 100 beats per minute Ventilation with the Bag Mask Provide ventilations with the bag mask at a rate of 30 to 60 breaths per minute if: The newborn’s breathing is slow or otherwise inadequate. The newborn’s heart rate is less than 100 beats per minute. The newborn’s trunk remains cyanotic despite the administration of blow-by oxygen. Reassess the infant’s color, respiratory effort, and heart rate after 30 seconds of ventilation. Cardiopulmonary Resuscitation Provide CPR if: The newborn’s heart rate is less than 60 beats per minute. Reassess the infant’s color, respiratory effort, and heart rate after 30 seconds of CPR and treat according to findings. Advanced Providers: See protocols for medications/dosages

Newborn Resuscitation AHA/AAP Guidelines Meconium -stained amniotic fluid: endotracheal suctioning of the depressed - not the vigorous child Hyperthermia should be avoided 100% oxygen is still recommended, however if supplemental oxygen is unavailable room air should be used Chest compression: Initiated if heart rate is absent or remains < 60 bpm despite adequate ventilation for 30 sec Medications: Epinephrine 0.01-0.03 mg/kg if heart rate < 60 bpm in spite of 30 seconds adequate ventilation and chest compression Volume: Isotonic crystalloid solution or 0-neg blood

Prognosis Apgar score < 5 at 10 minutes : nearly 50 % death or disability (Leicester) No spontaneous respiration after 20 min : 60 % disability in survivors (USA). No spontaneous respiration after 30 minutes : nearly 100 % disability in survivors (Newcastle).

Facts About Newborn Resuscitation The most important is to get air into the lungs Facts About Newborn Resuscitation

Hypoxic-ischemic encephalopathy(HIE) Hypoxic-ischemic encephalopathy is an important cause of permanent damage to central nervous system cells, which may result in - neonatal death - manifest later as cerebral palsy or mental deficiency

Essential criteria: 1. Metabolic acidosis on cord blood or very early (1 hour) neonatal blood (pH 7.0 or base deficit > 12 mmol/l.) 2. Early onset of severe or moderate neonatal encephalopathy in infants of > 34 weeks gestation. 3. Cerebral palsy of the spastic quadriplegic or dyskinetic type.

Criteria that together suggest A sentinel hypoxic event immediately before or during labour. A sudden, rapid and sustained deterioration of fetal heart rate. Apgar scores of 0-6 for longer than 5 minutes. Early evidence of multisystem involvement. Early imaging evidence of acute cerebral abnormality.