New guidelines for newborn resuscitation Newborn Baby by benbenzhou


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									                                                                                                                                          Acta Pædiatrica ISSN 0803–5253


New guidelines for newborn resuscitation
Ola Didrik Saugstad (
Department of Pediatric Research, Rikshospitalet Faculty Division, University of Oslo, Norway

Guidelines, Newborn resuscitation, Oxygenation,
O.D. Saugstad, Pediatrisk Forskningsinstitutt,
Rikshospitalet, 0027 Oslo, Norway.
Tel: +47 23072790/94 | Fax: +4723072780 |
26 August 2006; revised 21 November 2006;
accepted 6 December 2006.

                                                               The new guidelines from the International Liaison Committee on Resuscitation and American Heart
                                                               Association/American Academy of Pediatrics for newborn resuscitation underline that efficient
                                                               ventilation is the key to a successful resuscitation of the newly born infant. Compared with the former
                                                               guidelines published in 1999, the major changes are (i) less emphasis on using supplemental
                                                               oxygen when initiating resuscitation, (ii) no need for routine intrapartum oropharyngeal and
                                                               nasopharyngeal suctioning for vigorous infants born to mothers with meconium staining of amniotic
                                                               fluid, (iii) occlusive wrapping of very low birth weight infants <28 weeks to reduce heat loss is
                                                               recommended, (iv) preference for the intravenous versus endotracheal route for adrenaline and (v)
                                                               more emphasis on parental autonomy at the threshold of viability. A number of gaps in newborn
                                                               resuscitation have been identified and discussed.
                                                                Conclusion: The new guidelines for newborn resuscitation are more evidence-based than previously ones.
                                                                However, still there is a need for further research and modifications.

The International Liaison Committee on Resuscitation (IL-                                      suscitation, (ii) no need for routine intra-partum oropha-
COR) and its collaborating organizations such as the Amer-                                     ryngeal and nasopharyngeal suctioning for vigorous infants
ican Heart Association (AHA) and American Academy of                                           born to mothers with meconium staining of amniotic fluid,
Pediatrics (AAP) have established their new guidelines for                                     (iii) recommendation of occlusive wrapping of very low birth
newborn resuscitation on review of the evidence for each                                       weight infants <28 weeks to reduce heat loss, (iv) preference
step (1,2). In spite of the fact that newborn resuscitation is                                 for the intravenous versus endotracheal route for adrenaline
one of the most frequent procedures carried out in medicine,                                   (epinephrine) and (v) increased emphasis on parental au-
it is far from evidence-based. However, following the re-                                      tonomy at the threshold of viability. In the new guidelines
lease of the 1992 guidelines (3), a major effort to examine                                    establishing effective ventilation remains the primary objec-
the available evidence was undertaken in the 1999/2000                                         tive in the management of the apneic or bradycardiac new-
guidelines (4,5). This was done via a meticulous process                                       born infant in the delivery room.
where problematic areas were identified, all available liter-
ature in each area was collected and classified, and the best                                  Indications for resuscitation
possible conclusions were drawn on the basis of this pro-                                      The previous guidelines (6) listed five questions, which
cess. For the 2005/2006 guidelines, this process has con-                                      should be asked at each and every delivery:
tinued and even more refined guidelines have now been
                                                                                                1.   Is the amniotic fluid clear of meconium?
published. An aim is to make newborn resuscitation more
                                                                                                2.   Is the baby breathing or crying?
evidence-based and also to achieve international consensus
                                                                                                3.   Is there a good muscle tone?
of such guidelines. I will now review the specific changes
                                                                                                4.   Is the colour pink?
in the new guidelines based on ILCOR and AHA/AAP and
                                                                                                5.   Was the baby born at term?
provide some commentaries regarding each recommenda-
tion. The most important changes from 1999 to 2005 are:                                          Today we know that a newborn baby is not supposed to
(i) less emphasis on using 100% oxygen when initiating re-                                     be pink in the first few minutes of life (7). Therefore, in the

C   2007 The Author/Journal Compilation   C   2007 Foundation Acta Pædiatrica/Acta Pædiatrica 2007 96, pp. 333–337                                                 333
Resuscitation of the newly born infant                                                                                                                              Saugstad

new guidelines (8,9) the question concerning pink colour is                              According to the new guidelines, every baby of 28 weeks
removed. If the answers to the remaining four questions are                           gestational age or less should immediately without drying be
‘yes’, the baby does not need resuscitation and should not                            considered to be put into a plastic bag sealing up at the neck
be separated from the mother. If the answer to any of these                           in order to prevent heat loss. Covering the head is also of im-
questions is ‘no’ the infant should receive one or more of                            portance to prevent heat loss. Some would find it reasonable
the following four categories (blocks) of action in sequence.                         to apply this technique also in somewhat more mature in-
These blocks are named A (Airway), B (Breathing), C (Cir-                             fants. Body and skin temperature must be monitored closely
culation) and D (Drug). The decision to proceed from one                              to avoid hyperthermia with this technique. Hyperthermia
step to the other is determined by simultaneous assessment                            may be detrimental and has been associated with increased
of three vital signs: respirations, heart rate and colour. Each                       risk of brain injury (10,11).
category should be completed in about 30 sec of successful
ventilation. The infant is then evaluated. If the response is                         Clearing the airway of meconium
not adequate one should proceed to the next step.                                     Routine intra-partum oropharyngeal and nasopharyngeal
                                                                                      suctioning is not longer advised for infants born to mothers
A. Initial steps in stabilization (provide warmth, position,                          with meconium staining of amniotic fluid (12). Immediate
   clear airway, dry, stimulate, reposition).                                         endotracheal intubation and suctioning through the endo-
B. Ventilation. Breathing is assisted if the baby has apnea                           tracheal tube is not recommended in vigorous infants (i.e.
   or has a heart rate below 100 beats per minute (bpm).                              strong respiratory efforts, good muscle tone and heart rate
C. Chest compressions. Circulation is supported by starting                           > 100 bpm) (13). Endotracheal suctioning should be per-
   chest compression if heart rate is <60 bpm in spite of                             formed immediately after birth in non-vigorous infants with
   adequate ventilation.                                                              meconium in the amniotic fluid presuming the equipment
D. Medications or volume expansion. Drugs or volume ther-                             and expertise is available.
   apy is administered if heart rate is still below 60 bpm.
   If an infant is breathing sufficiently to improve colour and                       The new guidelines emphasize that proper positive pres-
maintain a heart rate >100 bpm, further artificial ventilation                        sure ventilation alone is effective for resuscitating almost
is not needed (8,9). Figure 1 summarizes the steps involving                          all apneic or bradycardiac newborn infants. This is the sin-
ventilation, chest compressions and medications and/or vol-                           gle most important intervention in resuscitating asphyxiated
ume expansion.                                                                        newborn infants that are not breathing at birth. A rapid in-
                                                                                      crease in heart rate is an indicator of the effectiveness of
Temperature control and heat preservation                                             resuscitation (14); however, the rise of the chest may give
The initial step of resuscitation is to provide warmth by plac-                       an immediate feed back of the effectiveness of ventilation.
ing the baby under a radiant warmer if one is available. The                          In one series consisting of 600 newborn infants in need of
baby should be dried and stimulated to breath.                                        resuscitation, a mean increase in heart rate from 90 bpm to

                                               Bag and mask indications: Hr < 100 and or apnea

                                                          Ventilate for 30 seconds:
                                                          Rate:      40- 60/min
                                                          Observe heart rate
                                                          Pressure: Visible rise and fall of chest

                                                                                     HR 60-100

                                 Continue ventilation
                                                                                                                  Check for spontaneous
                                 Start chest compressions HR < 60 Continue ventilation HR >100
                                 Consider intubation                                                              respirations
                                                                  Consider intubation

                                                HR < 60

                                     Drugs                                     Consider to move from one box to the next
                                     Volume Th erapy                           after 30 seconds successful ventilation

Figure 1 A simple flow sheet for the fundamental steps in newborn resuscitation from initiation of bag and mask ventilation via chest compressions to administration
of medications. HR: heart rate given as bpm.

334                                                         C   2007 The Author/Journal Compilation   C   2007 Foundation Acta Pædiatrica/Acta Pædiatrica 2007 96, pp. 333–337
Saugstad                                                                                                                           Resuscitation of the newly born infant

110 bpm occurred between 60 and 90 sec of life (15). An ini-                                   1:10 000 (0.1 mg/mL) is recommended. However, if the en-
tial pressure of 20 Cm H 2 O may be effective but a pressure                                   dotracheal route is used a higher dose (up to 0.1 mg/kg)
of ≥30–40 Cm H 2 O may be necessary in some babies (16).                                       should be considered.
   The new ILCOR/AHA/AAP guidelines accept bag-mask                                              Volume expansion is rarely needed in full term or near
ventilation to a newborn with a self-inflating bag, a flow-                                    term infants (19). However, if needed isotonic crystalloid so-
inflating bag or a T-piece mechanical device designed to                                       lution is presently the solution of choice at 10 mL/kg which
regulate pressure as needed to provide positive pressure ven-                                  may be repeated. AHA/AAP recommend infusion over 5–
tilation to a newborn.                                                                         10 min.

Oxygenation                                                                                    Ethics
There has been a quite dramatic swing in attitudes regard-                                     Guidelines for withholding and discontinuing resuscitation
ing the use of oxygen for newborn resuscitation since the                                      are given. They do not differ much from the previous guide-
1992 guidelines were published. In these guidelines it was                                     lines of 2000. However, the parent’s autonomy in these mat-
stated ‘If cyanosis, bradycardia, or other signs of neonatal                                   ters is emphasized more than previously. It is suggested that
distress are noted in a breathing newborn during stabiliza-                                    cardio- pulmonary resuscitation may be considered to be in-
tion, early administration of 100% oxygen is important’. And                                   terrupted after 10 min if there is unsuccessful establishment
furthermore, ‘The hazards of administering too much oxy-                                       of spontaneous heart rate and respiration: ‘After 10 minutes
gen during the brief period required for resuscitation should                                  of continuous and adequate resuscitative efforts, discontinu-
not be a concern’ (3).                                                                         ation of resuscitation may be justified if there are no signs of
   Today, there is increasing evidence that early administra-                                  life’. This is a rather brief observation time. Ten minutes go
tion of 100% O 2 is not as important and in fact may be                                        fast and although rare even when it takes more than 10 min
hazardous and therefore of concern (7,8). In fact, healthy                                     to re-establish the babies own cardiopulmonary function in-
newborn infants need 5–10 min to reach oxygen saturations                                      tact cerebral outcome can be obtained. However, evidence
in the 90% (7,9). The new guidelines therefore state ‘There is                                 regarding infants with 10 min of asystole suggests extremely
currently insufficient evidence to specify the concentration                                   poor outcome (20).
of oxygen to be used at initiation of resuscitation’. And ‘Once
adequate ventilation is established, if the heart rate remains                                 Identified gaps in newborn resuscitation
low, there is no evidence to support or refute a change in the                                 There still are a number of unanswered questions regarding
oxygen concentration that was initiated’. The new guidelines                                   newborn resuscitation. ILCOR has identified the following:
therefore leave it to the judgment of each centre or doctor
to decide the initial oxygen concentration.                                                     1. The ideal ratio of chest compressions to ventilation in
                                                                                                   cardiopulmonary resuscitation (CPR).
Intubation and CO 2 detection                                                                   2. The benefits and risks of supplementary oxygen during
Very few term or near term newly born infants are in need                                          CPR.
of tracheal intubation. Most babies in need of tracheal intu-                                   3. The benefits and risks of induced hypothermia following
bation are preterm infants. A laryngeal mask airway that is a                                      neonatal cardiac arrest.
mask fitting over the laryngeal inlet may be used if bag-mask
ventilation is unsuccessful and endotracheal intubation is                                        A number of others could be listed as well. For instance,
unsuccessful or not feasible.                                                                  the indications for volume therapy and which fluid is opti-
   In the new guidelines exhaled CO 2 detectors to confirm                                     mal. The optimal glucose level one should maintain is not
tracheal tube placement are recommended. They are reliable                                     described. In the new guidelines it is stated that infants re-
even in the smallest pre-term infants, provided there is not                                   quiring resuscitation should be treated and monitored to
a cardiac arrest (17). However, false negative results may be                                  maintain glucose in the normal range; however, this range
found. Therefore, before withdrawing the endotracheal tube                                     was not defined.
immediately the position of the tube should be checked first                                      Another important area for the future research is opti-
with direct laryngoscopy.                                                                      mal ventilation. Excessive tidal volume in pre-term infants
                                                                                               may be deleterious not only for the lungs but also for the
Medications and volume expansion                                                               brain. Today we know that too high or low tidal volume
Medication is rarely needed because 99.9% of newborns                                          may be deleterious to the pre-term newborn lungs. Data
will improve without. With adequate ventilation fewer than                                     from the study by Bjorklund et al. on newborn premature
2 per 1000 births will benefit from receiving adrenaline                                       lambs showed that even a few breaths with a high tidal
(18). If medication is needed in the acute phase of new-                                       volume may injure the lungs (21), and it is known that in-
born resuscitation adrenaline (epinephrine) is the most                                        flammatory processes are initiated using too low tidal vol-
important drug. According to the guidelines a narcotic an-                                     umes (22). The next generation of ventilation bags therefore
tagonist, sodium bicarbonate or vasopressors may be useful,                                    should offer the possibility to measure tidal volume. How-
however, very rarely. The endotracheal route for adrenaline                                    ever, Palme Kilander and Tunell (23) demonstrated that bag
administration no longer is recommended. The IV dose is                                        and mask ventilation is not as efficient for gas exchange as
0.01–0.03 mg/kg per dose. An adrenaline concentration of                                       spontaneous ventilation. If a baby can breathe successfully

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Resuscitation of the newly born infant                                                                                                                    Saugstad

on its own, interference should not be provided by health                   CONCLUSIONS
personnel. Milner et al. showed tidal volume is substan-                    ILCOR has estimated that as many as 10% of all newborn in-
tially higher when ventilating via an endotracheal tube com-                fants need some intervention at birth and approximately 1%
pared with bag and mask (24). This perhaps is not always an                 more extensive intervention (1). If this is correct, up to 13–
advantage.                                                                  14 million of the world’s annual newborn infants need in-
   Whether or not a PEEP should be used is not con-                         tervention and of these approximately 1.5 million will need
cluded in the new guidelines. It is clear from studies in                   intensive therapy. Optimal resuscitation procedures should
pre-term lambs that PEEP improves oxygenation (25). Al-                     therefore become a high priority. The new guidelines for
though very little data are available regarding any benefits                newborn resuscitation represent a major step forward and
of using PEEP in newborn resuscitation (26) many still be-                  may improve outcome of newly born infants. Still these
lieve this is beneficial. Randomized studies therefore should               guidelines are inadequate in many ways. For instance, the
be conducted exploring this and other questions as soon as                  recommendations to move from one step to the other after
possible.                                                                   30 sec may be too fast and to start chest compressions after
   From a practical point of view, it is a strength that the                30 sec of ventilation may be too early. The guidelines re-
guidelines give directions about how much time one should                   garding the use of 100% O 2 may be too conservative. How
spend before moving from one step to the next. Why 30                       to best ventilate a newly born baby who is not breathing due
sec has been chosen for each step is unclear to me. This                    to birth asphyxia is not clearly defined, what tidal volume to
seems to be a rather short period to assess the effect of                   use to obtain an adequate rise in heart rate should probably
bag and mask ventilation. Palme Kilander and Tunell have                    be addressed. A PEEP probably is beneficial and so may also
demonstrated it may take 1–2 min to achieve gas exchange of                 a moderate hypercapnia be.
2 mL/kg/min with bag and mask ventilation (23). Further-                      Therefore, there are already a number of topics to discuss
more, if heart rate is <60 bpm after 30 sec of efficient ventila-           for those who are planning the next resuscitation guidelines
tion, this bradycardia still is most often of respiratory origin            coming out in approximately 5 years.
and not cardiac. To start chest compressions that early is not
evidence based and these parts of the guidelines should be
   The optimal oxygen concentration obviously should be                       1. International Liaison Committee on Resuscitation. Part 7:
                                                                                 neonatal resuscitation. Resuscitation 2005; 67: 293–303.
determined. My opinion is that the use of 100% oxygen in
                                                                              2. American Heart Association. Neonatal Resuscitation.
primary resuscitation should be abandoned because we to-                         Circulation 2005; 112, (Suppl IV): 188–95.
day know this may be detrimental (27). A Cochrane review                      3. Guidelines for cardiopulmonary resuscitation and emergency
and another meta-analysis find room air reduces neonatal                         cardiac care: Emergency Cardiac Care Committee and
mortality with 30% (28) and 40% respectively (29). Further-                      Subcommittees, American Heart Association, part V: pediatric
more, a number of ill effects of short exposure of oxygen                        basic life support [see comments]. JAMA 1992; 268: 2251–61.
have been found both clinically and experimentally (30,31).                   4. Kattwinkel J, Niermeyer S, Nadkarni V, Tibballs J, Phillips B,
                                                                                 Zideman D, et al. ILCOR advisory statement: resuscitation of
It, therefore, is surprising that the AAP seems to be more
                                                                                 the newly born infant: an advisory statement from the
conservative than ILCOR and maintains that pure oxygen                           pediatric working group of the International Liaison
should be used initially, although the development in this                       Committee on Resuscitation. Circulation 1999; 99: 1927–38.
area is acknowledged and AAP supports the option using                        5. Niermeyer S, Kattwinkel J, Van Reempts P, Nadkarni V,
less than 100% oxygen (8,9). In Canada and Sweden, na-                           Phillips B, Zideman D, et al. International Guidelines for
tional guidelines have decided that newborn resuscitation                        Neonatal Resuscitation: an excerpt from the Guidelines 2000
                                                                                 for Cardiopulmonary Resuscitation and Emergency
should start out with room air.
                                                                                 Cardiovascular Care: international Consensus on Science.
   What we now need to determine is if there are any con-                        Contributors and Reviewers for the Neonatal Resuscitation
ditions where oxygen supplementation is truly needed and                         Guidelines. Pediatrics 2000; 106: E29–E44.
in such cases when should it be started. Should one start                     6. Kattwinkel J, editor. Textbook of neonatal resuscitation 4th
low and increase according to the needs as judged by pulse                       edition. American Academy of Pediatrics, American Heart
oximetry and/or the clinical response or start higher for in-                    Association 2000.
stance at 40% and reduce quickly? Furthermore, is oxygen                      7. Saugstad OD. Oxygen saturations immediately after birth.
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worse or perhaps better if there is a chorioamnionitis?
                                                                              8. Kattwinkel J, editor. Textbook of neonatal resuscitation 5th
   What the optimal paCO 2 is should now be added to the                         edition. American Academy of Pediatrics, American Heart
discussion of newborn resuscitation. Hypocapnia probably                         Association 2006.
is not beneficial for the newborn brain (32). However, per-                   9. American Heart Association. 2005 American Heart
haps a moderate hypercapnia should be aimed at in order                          Association (AHA) guidelines for cardiopulmonary
to accelerate normalization of cerebral blood flow? Experi-                      resuscitation (CPR) and emergency cardiovascular care (ECC)
mental data indicate this may be more important when re-                         of pediatric and neonatal patients: pediatric basic life support.
                                                                                 Pediatrics 2006; 117: e989–1004.
suscitation is carried out with 21% O 2 (33). The optimal level
                                                                             10. Petrova A, Demissie K, Rhoads GG, Smulian JC, Marcella S,
of pCO 2 is an area that is not discussed in the new guide-                      Ananth CV. Association of maternal fever during labor with
lines; however, this specific aspect should be emphasized in                     neonatal and infant morbidity and mortality. Obstet Gynecol
future research.                                                                 2001; 98: 20–7.

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Saugstad                                                                                                                            Resuscitation of the newly born infant

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