BIRTH ASPHYXIA. .

Discussion on asphyxiation conditions affection new borne

1. BIRTH ASPHYXIA K A F U T E B O R N F A C E B S c H B , M B C h B

2. Objectives Define Asphyxia List pre disposing factors of Asphyxia Explain patho -physiology of Asphyxia Make the diagnosis of Asphyxia Classify the severity of birth asphyxia

3. Definitions Asphyxia is the failure to initiate and maintain spontaneous and adequate breathing within 60 seconds of birth (WHO, 2013).  Asphyxia occurs as a result of impairment in gas exchange resulting in a decrease in oxygen in the blood and an excess of carbon-dioxide that leads to acidosis (Ricci, 2007).

4. Clinical features You should make the diagnosis of asphyxia when the baby exhibits one or more of the following clinical findings: Delay in breathing. An asphyxiated baby does not breathe at 1 minute (immediately after birth the baby is supposed to gasp and cry). Bradycardia (heart rate below 100 beats per minute) Central cyanosis (blue tongue) The baby is floppy or has poor muscle tone (does not move very much and is poorly responsive to stimuli) Note: Apgar scores are not useful indicators of the need for resuscitation, since resuscitation must begin long before the one-minute Apgar score is calculated.  Apgars can however be used as an indicator of the effectiveness of the resuscitation. 

5. PRE-DISPOSING FACTORS OF ASPHYXIA Maternal Factors Pre-eclampsia or eclampsia Abruptio placentae, placenta praevia or ante-partum haemarrhageHistory of previous neonatal deaths (NND) Prolonged rupture of membranes (PROM) Underlying medical conditions - infection, diabetes, essential hypertension Maternal exhaustion Placental insufficiency Cephalopelvic disproportion  (CPD)  

6. PRE-DISPOSING FACTORS OF ASPHYXIA Labour and Delivery Factors Operative vaginal delivery (forceps or vacuum-extraction) Breech or other abnormal presentation and difficult delivery Caesarean section (indication for C/S or anaesthetic drugs) Prolonged labour (latent phase >8 hrs , first stage >7 hrs and second stage >30 minutes in multipara and 1 hour in primigravida . Prolapsed umbilical cord or cord compression Sedative or analgesic drugs given before delivery as well as use of traditional medicines

7. PRE-DISPOSING FACTORS OF ASPHYXIA Foetal Conditions Prematurity Post-maturity Multiple births Foetal distress Intra uterine growth restriction (IUGR), Macrosomia Immaturity of pulmonary system Cerebral damage Meconium aspiration Abnormal lie Congenital abnormalities 

8. PATHO-PHYSIOLOGY OF ASPHYXIA Asphyxia results from persistently impaired gas exchange in the foetus during the perinatal period with consequent hypoxia, hypercapnia and consequently, acidosis (Creasy, 2009). The foetus is able to cope with a certain degree of hypoxia and initially manages to preserve the function of vital organs, however, when the situation is persistent, there is consequent hypoxic injury with necrotic damage to the tissues. All organ systems can be affected Brain injury referred to as hypoxic/ischemic encephalopathy (HIE) occurs due to impaired cerebral blood flow. This may manifest early with abnormal neurology like irritability, seizures, abnormal tone and posture, apnoeic episodes or irregular respirations; Cardiac injury can result in arrhythmias and cardiac arrest; kidney injury causing acute tubular necrosis with haematuria ,  anuria, oliguria or polyuria. The gastrointestinal tract may also become necrosis and this may manifest with abdominal distension, food intolerance, bloody stools. These must be anticipated and managed accordingly

9. Hypoxic Ischemic Encephalopathy (HIE) Intrapartum hypoxia may result in a syndrome called  hypoxic ischaemic encephalopathy (HIE) where a the neonate has experienced acute brain injury as expressed by encephalopathy as a consequence of hypoxia. HIE can be graded according to its severity and this provides a guide to the prognoses of the neonate Babies with mild and moderate HIE generally have a good prognosis and generally do well. An infant who, within a week of birth, is still floppy or spastic, unresponsive and cannot suck has a severe brain injury and will do poorly.

10. Management-Neonatal Resuscitation A-Airway If secretions, suction B-Breathing Bag and Mask ventilate if not breathing C-Circulation Iv fluids/ CPR/Inotropes C-Coma Intubation C-Convulsions Phenobarbitaone 20/kg loading dose, if seizures are controlled, then maintainance of 5/Kg. If not controlled repeat loading dose , then paraldehyde D-Don’t ever forget glucose/ Dehydration Check RBS and treat if <2.5 mmol /<45mg/dl Treat with 2ml/kg of 10% dextrose solution.