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About 10% of neonates require some degree of resuscitation at delivery. Causes are numerous (see Table 1: Perinatal Problems: Problems That May Require Resuscitation), but most involve asphyxia or respiratory depression. Incidence rises significantly if birth weight is < 1500 g.

Assessment: The Apgar score assigns 0 to 2 points for each of 5 measures of neonatal health (Appearance, Pulse, Grimace, Activity, Respiration—see Table 2: Perinatal Problems: Apgar Score). Scores depend on physiologic maturity, maternal perinatal therapy, and fetal cardiorespiratory and neurologic conditions. A score of 7 to 10 at 5 min is considered normal; 4 to 6, intermediate; and 0 to 3, low. A low Apgar score is not by itself diagnostic of perinatal asphyxia but is associated with a risk of long-term neurologic dysfunction. An unduly prolonged (> 10 min) low Apgar score predicts increased risk of mortality in the first year of life.

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The earliest sign of asphyxia is acral (peripheral) cyanosis, followed by decreases in respiration, muscle tone, reflex response, and heart rate. Effective resuscitation leads initially to increased heart rate, followed by improved reflex response, color, respiration, and muscle tone. Evidence of intrapartum fetal distress, persistence of an Apgar score of 0 to 3 for > 5 min; an umbilical arterial blood pH < 7; and a sustained neonatal neurologic syndrome that includes hypotonia, coma, seizures, and evidence of multiorgan dysfunction are manifestations of perinatal asphyxia. The severity and prognosis of posthypoxic encephalopathy can be estimated with the Sarnat classification (see Table 3: Perinatal Problems: Clinical Staging of Posthypoxic Encephalopathy) in conjunction with EEG, neuroradiologic imaging, and brain stem auditory and cortical evoked responses.

Table 1
Problems That May Require Resuscitation Failure to breathe Antepartum mechanism Diabetes Intrauterine growth restriction Maternal toxemia Renovascular hypertension Recent intrapartum asphyxia Cord compression Cord prolapse Fetal exsanguination Maternal hypotension Placenta previa Placental abruption Uterine tetany CNS depression Congenital abnormalities of the brain stem Intracerebral hemorrhage Spinal cord injury Drugs Analgesics or hypnotics Anesthetics Magnesium Opioids, maternal drug abuse Failure to expand the lungs Airway obstruction Blood Meconium Mucus Prematurity (respiratory distress syndrome) Malformations involving the respiratory tract Agenesis Diaphragmatic hernia Hypoplasia Stenosis or atresia

Resuscitation: Initial measures for all neonates include suctioning and tactile stimulation. Suctioning requires appropriately sized catheters (see Table 3: Cardiac Arrest: Guide to Pediatric Resuscitation—Mechanical Measures) and pressure limits of 100 mm Hg (136 cm H₂O). Tactile stimulation (eg, flicking the soles of the feet, rubbing the back) may be necessary to encourage regular, spontaneous breathing. Infants not responding with appropriate respirations and heart rate require O₂ therapy, bag-mask ventilation, sometimes endotracheal intubation, and much less commonly, chest compressions (see Fig. 2: Perinatal Problems: Level of intrauterine growth based on gestational age, body length (A), and head circumference (B) at birth. and see Fig. 2: Cardiac Arrest: Chest compression.).

The infant is quickly dried and placed supine under a preheated overhead warmer in the delivery room. The neck is supported in the neutral position with a rolled towel under the shoulders.

O₂ should be given at 10 L/min through a face mask attached to a self-inflatable or anesthesia bag; if no mask is available, O₂ tubing may be placed adjacent to the face and set to deliver 5 L/min. If spontaneous respirations are absent or heart rate is < 100 beats/min, respirations are assisted with the bag-mask. Bradycardia in a distressed child is a sign of impending cardiac arrest; neonates tend to develop bradycardia with hypoxemia. Advanced resuscitation techniques, including endotracheal intubation, and selection of equipment size, drugs and dosages, and CPR parameters are discussed elsewhere (see Cardiac Arrest: CPR in Infants and Children).

Table 2
Apgar Score Score* Criteria Mnemonic 0 1 2 Color Appearance All blue, pale Pink body, blue extremities All pink Heart rate Pulse Absent < 100 beats/min > 100 beats/min Reflex response to nasal catheter/tactile stimulation Grimace None Grimace Sneeze, cough Muscle tone Activity Limp Some flexion of extremities Active Respiration Respiration Absent Irregular, slow Good, crying *A total score of 7–10 at 5 min is considered normal; 4–6, intermediate; and 0–3, low.

Table 3
Clinical Staging of Posthypoxic Encephalopathy Factor Stage I (Mild) Stage II (Moderate) Stage III (Severe) Duration < 24 h 2–14 days Hours to weeks Level of consciousness Hyperalertness and irritability Lethargy Deep stupor or coma Muscle tone Normal Hypotonia or proximal limb weakness Flaccidity Tendon reflexes Increased Increased Depressed or absent Myoclonus Present Present Absent Complex reflexes Sucking Active Weak Absent Moro response Exaggerated Incomplete Absent Grasping Normal to exaggerated Exaggerated Absent Oculocephalic (doll's eye) Normal Overreactive Reduced or absent Autonomic function Pupils Dilated Constricted Variable or fixed Respiration Regular Variable in rate and depth, periodic Irregular apnea Heart rate Normal or tachycardic Low resting < 120 beats/min Bradycardia Seizures None Common (70%) Uncommon EEG Normal Low voltage, periodic or paroxysmal, epileptiform activity Periodic or isoelectric Risk of death < 1% 5% > 60% Risk of severe handicap < 1% 20% > 70% Adapted from Sarnat HB, Sarnat MS: Neonatal encephalopathy following fetal distress. Archives of Neurology 33:696–705, 1975.

Fig. 3
HR = heart rate. Adapted from Neonatal Resuscitation Textbook, ed. 5. American Academy of Pediatrics and American Heart Association, Appendix, p. 6–2, 2006. Algorithm for resuscitation of neonates.

Last full review/revision March 2007 by James W. Kendig, MD

Content last modified July 2010