Neonatal resuscitation

Overview 340

Practical aspects 342

Airway, breathing, and circulation (ABC) 342

Drugs 346

Recent advances 347

Communication with parents 348

340 CHAPTER 8 Neonatal resuscitation

Overview

Most babies establish normal respiration and circulation without help after delivery. However, all babies should be assessed at delivery. Newborn infants who are born at term, have clear liquor, and are breathing and crying with good tone will only require drying and keeping warm. Less than 1% of babies need resuscitation. Anticipation of problems before delivery is the key to success.

It is prudent, where possible, to call for specialist skilled personnel to attend deliveries where need for additional support may be anticipated. These situations include:

•Preterm deliveries.

•Emergency Caesarean deliveries.

•Vaginal breech birth.

•Thick meconium-stained liquor.

•Major fetal abnormality.

•Other concerns (multiples, signs of significant fetal compromise).

All trained personnel attending a delivery have a responsibility for initiating resuscitation at birth and should possess the appropriate knowledge and skills to approach the management of the newborn infant during the first 10–20min in a competent manner. The environment should be warm, draught free, and well lit, with a flat surface available for resuscitation. Equipment should be checked on a daily basis and before each delivery.

Some of the important items are:

•A warmed flat surface (Resuscitaire with radiant warmer) (see Fig. 8.1).

•Source of air and oxygen with pressure-limited gas delivery.

•Appropriate size face masks, oropharyngeal airways, endotracheal tubes.

•Suction device with different size suction catheters.

•Stethoscope.

•Laryngoscope with straight laryngeal blades.

•Instruments for clamping and cutting the umbilical cord.

•Emergency resuscitation box for advanced resuscitation.

•Clock or stopwatch.

OVERVIEW 341

Fig. 8.1 Neonatal radiant warmer (Resuscitaire). Reproduced with permission of Dräeger Medical UK, 2008.

342 CHAPTER 8 Neonatal resuscitation

Practical aspects

Temperature control

Hypothermia can lower oxygen tension, increase metabolic acidosis, lead to hypoglycaemia, and inhibit the production of surfactant. Low temperature is associated with poor neonatal outcome.

Heat loss should be prevented by:

•Protecting the baby from draught.

•Keeping the delivery room warm.

•Drying the term baby immediately after delivery, covering the head and body with warm towel to prevent further heat loss.

•Placing baby on warm surface under radiant warmer, if resuscitation is needed.

2For a preterm baby born before 28wks of gestation (<71kg birth weight), the most effective way of keeping the baby warm is not to dry and wrap it in warm towels, but to cover the head and body (apart from the face) with a plastic bag before placing under a radiant heater. Plastic wrapping should therefore be available at all deliveries of extremely preterm infants.

Initial assessment at delivery

The immediate assessment includes colour, tone, breathing, and heart rate. Apgar scoring is often used for the initial assessment of the baby. However, it is a retrospective, highly subjective tool and was never intended to identify babies needing immediate resuscitation.

•Colour: baby may be centrally pink, cyanosed, or pale (peripheral cyanosis is common and does not by itself indicate hypoxaemia).

•Tone: a very floppy baby is likely to be unconscious, and may need respiratory support.

•Breathing: the rate, depth, and symmetry of respiration together with any abnormal breathing pattern such as grunting and gasping should be noted.

•Heart rate: best evaluated by auscultating with a stethoscope (palpating the umbilical cord is often effective, but can be misleading).

After the initial assessment, infants can be generally classified into one of four groups and further management guided by this (Table 8.1).

Further reading

How to perform an Apgar score. Mhttp://www.youtube.com/watch?v=hdNVhDuD4wU

344 CHAPTER 8 Neonatal resuscitation

Airway, breathing, and circulation (ABC)

Call for skilled help as soon as a problem is identified.

Airway

The head should be placed in neutral position. This is different from the head position for adult resuscitation because of the relatively large occiput of babies. Overextension of the neck can occlude the airway. A jaw thrust may be helpful, but care must be taken not to compress the airway under the chin. Use of an appropriately sized Guedel airway can be considered, particularly in infants with micrognathia. Suction of the airway is only required if there is blood or particulate material in the oropharynx. Aggressive pharyngeal suction should be avoided and suction should always be done under direct vision with a laryngoscope.

Blind suction is not helpful; even in the presence of meconium-stained liquor. It may lead to trauma and induce bradycardia or laryngospasm.

Breathing

Mask ventilation may be necessary if the infant is apnoeic, has irregular breathing, or is bradycardic. The aim is to achieve adequate lung inflation and to deliver oxygen. In most cases mask ventilation is as effective as intubation in the initial resuscitation scenario.

It is essential to use the correct-sized mask. The mask should cover the nose and mouth, but should not extend beyond the chin or over the orbits. Mask ventilation can be performed using a bag and mask, or via a constant flow T-piece system (Fig. 8.2).

The lungs of newborn infants are fluid-filled immediately after birth and the first 5 breaths given should sustain an inflation pressure of approximately 30cm of water (for a term infant) for 2–3s (inflation breaths). These long breaths aim to displace the lung fluid and expand the lungs. If effective, chest wall movement and improvement of heart rate should be seen. If the heart rate rises, but baby is still not breathing, continue to ventilate at 30–40 breaths/min (maintain the inflation for 71s for each breath).

If there is no improvement, the airway should be checked again. Help should be sought and early additional assistance will be beneficial if there is no improvement.

Circulation

Chest compressions are effective only if the lungs have been successfully inflated.

Chest compressions aim to deliver oxygenated blood to the heart allowing the circulation to recover. Chest compressions should be commenced if the infant remains bradycardic despite adequate ventilation.

AIRWAY, BREATHING, AND CIRCULATION (ABC) 345

How to perform chest compressions in the neonate

•Both thumbs should be placed over the lower 1/3 of the sternum, encircling the chest with both hands; other fingers lie behind the baby supporting the back.

•For effective chest compressions, the chest is compressed to a depth of 1/3 the anteroposterior diameter allowing the chest wall to return to its relaxed position between compressions.

•3:1 ratio of compression and ventilation is used, i.e. 90 compressions and 30 breaths/min, each breath lasting for 1s.

•The quality of compressions and ventilation are more important than the rate.

•Recheck the heart rate after 30s and every 30s after that.

Video teaching basic neonatal resuscitation to midwifery students. Mhttp://www.youtube. com/watch?v=TWaZBcjmxu8

Fig 8.2 Neonatal resuscitation. (a) Incorrect head position. Neonates have a prominent occiput and in the prone position will naturally adopt flexed head posture, compromising the airway. (b) Correct ‘neutral’ head position. Neutral position is neither extended nor flexed, but opens the airway to allow effective inflation breaths.

346 CHAPTER 8 Neonatal resuscitation

Drugs

Drugs are rarely indicated in neonatal resuscitation. They should be considered only if adequate ventilation and effective chest compression have failed to increase the heart rate above 60 beats/min. In the resuscitation situation, drugs should be given via an umbilical venous catheter.

Drugs used in neonatal resuscitation

•Adrenaline: 1:10 000, dose 0.1–0.3mL/kg equivalent to 10–30 micrograms/kg; route through umbilical venous catheter or IV.

2Adrenaline should not be given down the endotracheal tube (ETT).

•Sodium bicarbonate: dose 1–2mmol/kg (2–4mL/kg of 4.2% NaHCO3); route through IV or UVC. Reversing the intracardiac acidosis may help bump-start the heart.

2 Repeated doses of NaHCO3 should be avoided without proper evidence of metabolic acidosis from blood gas analysis.

•Glucose 10%: dose 2mL/kg/dose (200mg/kg/dose), route through IV or UVC. Glucose should be given if there is hypoglycaemia.

•Volume replacement: crystalloid (0.9% saline, 10mL/kg/dose) is the preferred fluid if the infant appears to be in shock. Blood should be given if there is evidence of hypovolaemia and evidence of acute blood loss.

•Naloxone: is no longer kept in the resuscitation trolley.

Actions in the event of a poor response to resuscitation

Check for a technical problem

•Is the gas flow connected?

•Is there a leak in the circuit? Check the tubing.

•Is the ETT in the trachea? If in doubt remove ETT, give breaths by mask, and replace ETT if necessary.

•Is the ETT blocked? If in doubt remove ETT, give breaths by mask, and replace ETT if necessary.

•Check the blow-off valve pressure (30cm of water for term infant).

Does the baby have other pathology?

•Pneumothorax.

•Congenital lung problem, e.g. diaphragmatic hernia.

•Lung hypoplasia.

•Hydrops fetalis.

•Perinatal asphyxia.

RECENT ADVANCES 347

Recent advances

Delayed cord clamping

For uncompromised babies, a delay in cord clamping of at least 1min from complete delivery of the infant is now recommended.

Infants with meconium-stained liquor

There is now evidence that suctioning of the meconium from the infant’s airway after delivery of the head but before delivery of the shoulder is not beneficial and so it is no longer recommended.

2No suctioning should be performed if the infant is active, vigorous, and crying.

If an infant is born through thick meconium and is floppy and depressed after birth, it is reasonable for a skilled person to inspect the larynx directly with a laryngoscope and suction the oropharynx and trachea. There is no role for bronchial lavage.

Preterm infants

It is easier to maintain the preterm infant’s temperature by placing it into a food-grade plastic wrap or bag (while wet, leaving the face uncovered) and then under a radiant heater. This is more effective than drying and wrapping for infants <28wks gestation. For these infants the delivery room temperature should be at least 26°C.

Also, preterm infants usually require less pressure to inflate their lungs and therefore the blow-off valve on the Resuscitaire should be initially set at 20–25cm of water (rather than 30cm of water for term infants). In addition, exogenous surfactant is important in the initial stabilization of extremely preterm infants.

Use of air vs. oxygen in resuscitation

X There is evidence that using air for the resuscitation of near-term and term babies is as effective as using oxygen, although there is still active debate. It is therefore reasonable to resuscitate infants in air, with supplemental oxygen available if needed and its use guided by pulse oximetry.

Confirmation of tracheal tube placement

Detection of exhaled carbon dioxide in addition to clinical assessment is recommended as the most reliable method to confirm placement of a tracheal tube in neonates with spontaneous circulation.

Therapeutic hypothermia

Newly born infants born at term or near term with evolving moderate to severe hypoxic-ischaemic encephalopathy should, where possible, be offered therapeutic hypothermia. This does not affect immediate resuscitation, but is important for post-resuscitation care.

348 CHAPTER 8 Neonatal resuscitation

Communication with parents

Resuscitation decisions

If resuscitation is required, parents should be fully informed of the procedure undertaken and the purpose.

The decision to resuscitate an extremely preterm infant should be a combined decision of parents, and paediatric and obstetric staff. This is a difficult conversation, but one that is best had early. The obstetricians caring for any woman who has a strong probability of delivering very prematurely must raise the issue early and actively involve their paediatric colleagues. The decision taken about resuscitation should also influence the level of fetal monitoring in labour.

The decision to discontinue resuscitation should involve senior paediatric staff. Proper birth plans should be in place in cases of severe congenital malformations. All communication with parents should be documented in the mother’s notes and later in the baby’s notes after delivery.

Stopping resuscitation

If there are no signs of life after 10min of continuous and effective resuscitation, it is appropriate to consider stopping ongoing attempts as the outcome is universally poor. The decision should be made by the resuscitation team and the most senior staff available. Local and national guidelines are very helpful in making such decisions.

Further reading

Biarent D, Binghma R, Richmond S, et al. (2005). European Resuscitation Council Guidelines for resuscitation. Resuscitation 67(S1): S97–S133.

Resuscitation Council (UK). (2011). Resuscitation at birth. Newborn life support course provider manual, 3rd edn. London: Resuscitation Council (UK).

Richmond S, Wyllie J. (2010). European Resuscitation Council Guidelines for Resuscitation (2010). Section 7: Resuscitation of babies at birth. Resuscitation 81: 1389–9.