NOTE--This section of the Peripheral Brain is largely based on a 1994 edition of the American Academy of Pediatrics Neonatal Resuscitation handbook.  Changes in recommended protocols may have been made during that time.  As with all sections of the Peripheral Brain, no claim as to currency or completeness is made to this content.  Please read the  DISCLAIMER for more information.

I. Pathophysiology

  1. "Depression" vs. "Asphyxia"
  1. Depression = decreased mm. tone +/- inadequate resp. effort. Causes include:
  1. Intrauterine asphyxia
  2. Prematurity
  3. Drugs/meds given intrapartum
  4. Congenital malformation
  5. Congenital neuromusc. disease
  1. Asphyxia = hypoxia & resp. acidosis
  1. Primary vs. secondary apnea
  1. Primary apnea
  1. Initial response to hypoxemia
  2. Initial tachypnea, then apnea, bradycardia, decreased neuromusc. tone
  3. Us. responds to stimulation & blow-by O2
  1. Secondary apnea
  1. Follows primary apnea
  2. Deep gasping respirations followed by apnea, bradycardia, decreased neuromusc. tone, and hypotension
  3. Will only respond to assisted ventilation w/supplemental O2; if not done, death/brain damage rapidly ensues
  1. Note that primary & secondary apnea are clinically indistinguishable; therefore, tx all as secondary
  2. Presence of resp. effort does not guarantee that adequate ventilation is taking place. Deep respirations are required to clear lung fluid & bring about initial oxygenation, which is required for the initial pulmonary vasodilation that allows lung to be perfused rather than RV output going through ductus arteriosus

II. Risk factors for depression/asphyxia in a neonate

  1. Antepartum factors
  1. Maternal age > 35yo
  2. Maternal DM
  3. Hypertensive disorders including chronic HTN and preeclampsia
  4. Fetal anemia or isoimmunization
  5. Previous fetal/neonatal death
  6. Bleeding in 2nd or 3rd TM
  7. Maternal infection
  8. Oligohydramnios
  9. Polyhydramnios
  10. PROM
  1. Intrapartum factors
  1. Emergency c/s
  2. Abnormal presentation
  3. Premature labor
  4. Post-term gestation
  5. PROM > 24h before delivery
  6. Precipitous or prolonged (> 24h) labor
  7. Prolonged stage 2 (> 2h)
  8. Multiple gestation
  9. IUGR
  10. Macrosomia
  11. Congenital malformation
  12. Meds administered to mom (esp. narcotics, Lithium, Magnesium, and beta-blockers)
  13. Drugs of abuse
  14. Decreased fetal movement or nonreassuring FHR
  15. Inadequate prenatal care
  16. Use of general anesthesia
  17. Uterine tetany
  18. Meconium staining of amniotic fluid
  19. Cord prolapse
  20. Abruptio placentae
  21. Placenta previa

III. Basic algorithm

  1. Tactile stimulation/dry & warm at same time unless mec is present & you want to suction before first breath!
  1. Position face up w/neck slightly extended (consider shoulder roll if lots of molding)
  2. Suction mouth (careful not to stimulate post. pharynx which can produce vasovagal rxn) then nose
  3. If meconium is present:
  1. Suction mouth/nose w/Delee on the perineum
  2. If thin mec + depressed baby or thick/particulate mec regardless of activity, also, before drying, intubate & suction hypopharynx (may require several passes to remove all mec, suctioning x 3-5secs at a time w/suction < 100mm Hg; can do w/laryngoscope and 10 or 12F suction catheter as alternative to ET tube w/meconium aspirator)
    1. Intubation & endotracheal suctioning may not reduce risk of meconium aspiration syndrome--see under MAS
  3. If requires tracheal suctioning, then after baby is stable, suction stomach to prevent aspiration of mec-containing gastric contents (may cause vagal response)
  1. If adequate, proceed to D.
  2. If inadequate or absent resp. effort, can try brief tactile stimulation (rub back or flick soles of feet) + blow-by O2
  3. If ineffective, proceed to positive-pressure ventilation (PPV)
  4. Important #'s
  1. Bag should be approx. 750ml capacity
  2. 20-30ml/per ventilation for term neonates
  3. 40-60 ventilations/min
  4. Pressure should be 15-20cm H20; up to 40cm for first few breaths and in infants with decreased pulmonary compliance (e.g. many preemies)
  1. Self-inflating bag must have an O2 reservoir to ensure delivery of high O2 concentration
  2. After 15-30sec, CHECK HR (not before!)
  1. If > 100, continue PPV until spont. resps. occur
  2. If 60-100 and increasing, continue PPV until HR > 100 and spont. resps. occur
  3. If 60-100 and not increasing
  1. Continue PPV, confirming that ventilation is adequate (chest movement, breath sounds) & using 100% O2
  2. If HR < 80, start chest compressions & continue till HR > 80 (1/2-3/4"; 3:1 chest compressions: ventilation; compressions approx 90/min)
  3. If < 60
  1. Continue PPV, confirming that ventilation is adequate (chest movement, breath sounds) & using 100% O2
  2. Start chest compressions & continue till HR > 80
  3. Continue to monitor HR and, periodically, spont. resp. effort, as long as continuing to provide PPV
  1. Always place orogastric tube (8F) if needing to do bag-mask ventilation for > 2 minutes (measure length nose-ear-xyphoid)
  2. Consider endotrachial intubation tube rather than bag-mask for when prolonged PPV is required, for small preemies, when bag-mask ventilation is difficult, or when diaphragmatic hernia is suspected
    1. Early nasal continuous positive airway pressure (ENCPAP)--A form of respiratory support which may reduce the incidence of need for endotracheal intubation.
  3. Always provide temporary blow-by 100% O2 after d/c'ing PPV, then withdraw slowly
  4. Notes on Oxygen Saturation measurement immediately after birth
    1. 2 studies on healthy newborns (J. Peds. 148:585, 2006--JW and J. Peds. 148:590, 2006--JW) yielded the following data; sats were lower in babies born by cesarian section than babies born vaginally:
      1. At 1 minute, median SaO2 was 63%
      2. At 2 minutes, median SaO2 was 70%
      3. At 3 minutes, median SaO2 was 76% in one study and in another, 87% for babies born vaginally and 81% for babies born by c/s
      4. At 4 minutes, median SaO2 was 81%
      5. At 5 minutes, median SaO2 was 90%
  1. Check HEART RATE
    1. If heart rate is < 100 BPM
  1. Initiate PPV, even if breathing spontaneously
  2. See above for criteria for chest compressions (in infants requiring PPV)
  1. Check COLOR
  1. If central cyanosis is present, even if resps & HR are nl, give 100% blow-by O2 (5l/min of greater)
  2. If central cyanosis persists despite 100% blow-by O2, start PPV, even if resps & HR are nl
  1. Assess Apgar at 1 and 5 minutes and if < 7 at 5 minutes, continue Q5min for up to 20min or until 2 sucessive scores are 8 or more

IV. Meds

  1. Use of Oxygen versus Air for respiratory resuscitation
    1. In a meta-analysis of five clinical trials (only two strictly randomized) comparing air vs. 100% O2 in 1,302 neonates with asphyxia (defined as apnea and bradycardia), mortality was sig. lower in infants resuscitated with air vs. O2 (RR 0.71). Most pts in these studies were in developing countries. (Lancet 364:1329, 2004--JW)
  2. Can be given by umbilical venous catheter (preferred), peripheral vein, or w/some meds (epi, naloxone), through ET tube
  3. Note that some meds can cause intracranial bleeding if given too rapidly (e.g. volume expanders, bicarbonate)
  4. In prolonged resuscitations consider specific causes of continued neonatal depression: pneumothorax, persistent pulmonary vasoconstriction, diaphragmatic hernia
  5. Indications for meds:
  1. No HR is present
  2. HR < 80/min despite adequate ventilation w/100% O2 + chest compressions x 30sec
  1. Can d/c meds when HR > 100
  2. Epinephrine
  1. Increases heart rate, cardiac contractility, and causes peripheral vasoconstriction
  2. First med to use when meds are needed (see above for criteria)
  3. Dose = 0.1-0.3ml/kg of 1:10,000 solution IV or through ET tube
  4. For ET tube administration, dilute w/NS to 1-2ml volume for ease of administration; if doesn't respond, can use up to 1-2ml/kg
  5. If HR doesn't go up to 100/min within 30sec, consider repeat Epi (up to Q3-5min) or vol. expanders (esp. if suspect hypovolemia) vs. bicarbonate (esp. if prolonged arrest)
  1. Volume expanders
  1. Hypovolemia should be suspected in any neonate that does not respond well to basic resuscitative efforts
  2. Use particularly when suspect acute blood loss (pallor, weak pulses)
  3. Increase vascular volume & decrease metabolic acidosis by increasing tissue perfusion
  4. Four different options:
  1. Whole-blood
  2. 5% Albumin-saline
  3. Normal saline
  4. Lactated Ringer's
  1. Dose = 10ml/kg over 5-10min
  2. Can repeat dose if no response; also if no res ponse, consider use of bicarbonate
  1. Sodium Bicarbonate
  1. Recc'd only in prolonged arrests with no response to other therapy
  2. Helps to correct metabolic acidosis; also provides some volume expansion from hypertonic solution of Na
  3. Effective ventilation is necessary in order to clear CO2 released by the administration of bicarb
  4. Recc'd dose = 2mEq/kg (of 0.5mEq/ml = 4.2% solution) IV over at least 2min
  5. If HR doesn't go up to 100/min within 30sec, consider another dose of Epi and/or volume expanders, or Dopamine if appears hypotensive
  1. Naloxone
  1. Indicated for severe resp. depression w/ maternal narcotic intake < 4h previously
  2. Dose = 0.1mg/kg (0.4mg/ml or 1.0mg/ml) IV or through ET tube; can also give SQ or IM
  3. Duration of action = 1-4h which may be less than that of the narcotic in question, so be prepared to re-administer after 1-4h!
  4. May cause sz if given to baby of a narcotic-addicted mother
  1. Dopamine
  1. Indications = prolonged resuscitation w/signs of shock
  2. Pharmacology: increases cardiac contractility; may cause tachycardia
  3. Dose: continuous infusion starting at 5ug/kg/min, can increase up to 20ug/kg/min
  4. Must continuously monitor HR and BP (check HR Q30-60sec & BP Q2min for first 15min; then HR and BP Q3-5min until BP stabilized)

V. Intubation

  1. Suggested choice of ET tube:
  1. < 1000g or < 28wks: 2.5mm
  2. 1000-2000g or 28-34wks: 3.0mm
  3. 2000-3000g or 34-38wks: 3.5mm
  4. >3000g or >38wks: 3.5-4.0mm
  1. Use blow-by 100% O2 at 5l/min during intubation attempt
  2. Insert till black line is at vocal cords
  3. Try cricoid pressure if have trouble visualizing the cords
  4. Restrict attempts to 20sec; if don't get it, bag/mask for a while and try again
  5. Tape in place; make note of depth of insertion in case position shifts after insertion
  6. Confirm tube placement w/breath sounds, chest elevation, & CXR; listen & watch for signs of abdominal air entry
  7. When suctioning through ET tube, make sure suction is < 100mm Hg

VI. Resuscitation equipment

  1. Baby warmer, turned on & warmed up
  2. Suction equipment
    1. Bulb syringe
    2. Mechanical suction
    3. Suction catheters 5 or 6F, 8F, 10F
    4. 8F feeding tube and 20ml syringe
    5. Meconium aspirator
  3. Bag-Mask equipment
    1. Neonatal resuscitation bag w/ pressure-release valve or pressure gauge
    2. Face masks, newborn and preemie-size
    3. Oral airways, newborn and preemie-size
    4. O2 w/flowmeter & tubing
  4. Intubation equipment
    1. Laryngoscope w/straight blades, #0 and #1, w/extra bulbs & batteries
    2. ET tubes, 2.5, 3.0, 3.5, 4.0mm
    3. Stylet
    4. Scissors
  5. Meds
    1. Epinephrine 1:10,000; 3ml or 10ml ampules
    2. Naloxone 0.4mg/ml-1ml ampules OR 1.0mg/ml-2ml ampules
    3. Volume expander, e.g. 5% albumine, NS, LR
    4. Bicarbonate 4.2% (5mEq/10ml)-10ml ampules
    5. Dextrose 10%; 250ml
    6. Sterile H2O; 30ml
    7. NS; 30ml
  6. Misc.
  1. Stethoscope
  2. Cardiotachometer w/EKG
  3. Adhesive tape
  4. Syringes, 1, 3, 5, 10, 20, 50ml
  5. Needles, 25, 21, 18g
  6. Alcohol sponges
  7. Umbilical a. catheterization tray w/umbilical tape & umbi catheters 3.5F and 5F
  8. 3-way stopcocks
  9. Feeding tube, 5F

VII. Use of cooling for neonatal asphyxia

  1. In a study in 208 newborns born at gestational age 36wks or greater with hypoxic-ischemic encelophalopathy (defined as either severe acidosis or perinatal complications + resuscitation at birth) randomized to usual care (overhead radiant warmers) vs. whole-body cooling (titrated to achieve an esophageal temperature of 33.5'C) x 72; the whole-body cooling pts had sig. lower incidence of (death or mod-severe disability) at 18-22mos (44% vs. 62%) (NEJM 353:1574, 2005--JW)

(Source: AAP/AHA, "Textbook of Neonatal Resuscitation", 1994)