Managing Oxygen Therapy during Delivery Room Stabilization of Preterm Infants
2011; Elsevier BV; Volume: 160; Issue: 1 Linguagem: Inglês
10.1016/j.jpeds.2011.07.045
ISSN1097-6833
AutoresJennifer A. Dawson, Máximo Vento, Neil N. Finer, Wade Rich, Ola Didrik Saugstad, Colin J. Morley, Peter G. Davis,
Tópico(s)Respiratory Support and Mechanisms
ResumoIn October 2010, the International Liaison Committee on Resuscitation released new guidelines for neonatal resuscitation, which expanded on the previous recommendations for the use of pulse oximetry during neonatal resuscitation. In this Commentary, we discuss oxygen treatment in the delivery room. Where available, we have used evidence from randomized controlled trials (RCTs). Where this evidence is lacking, we have relied on observational and animal data to inform our strategy for using supplemental oxygen in the delivery room. Early-generation pulse oximeters took several minutes to provide an accurate reading and, thus, were not useful for making decisions during neonatal resuscitation. However, modern pulse oximeters, when applied properly, can provide measurements within 90 seconds of birth.1Altuncu E. Ozek E. Bilgen H. Topuzoglu A. Kavuncuoglu S. Percentiles of oxygen saturations in healthy term newborns in the first minutes of life.Eur J Pediatr. 2008; 167: 687-688Crossref PubMed Scopus (51) Google Scholar, 2House J.T. Schultetus R.R. Gravenstein N. Continuous neonatal evaluation in the delivery room by pulse oximetry.J Clin Monit. 1987; 3: 96-100Crossref PubMed Scopus (83) Google Scholar, 3Kopotic R.J. Lindner W. Assessing high-risk infants in the delivery room with pulse oximetry.Anaesth Analg. 2002; 94: S31-S36PubMed Google Scholar, 4Rabi Y. Yee W. Chen S.Y. Singhal N. Oxygen saturation trends immediately after birth.J Pediatr. 2006; 148: 590-594Abstract Full Text Full Text PDF PubMed Scopus (175) Google Scholar, 5Sendak M.J. Harris A.P. Donham R.T. Pulse oximetry in newborn infants in the delivery room.Anesthesiology. 1985; 62: A433Crossref Google Scholar Studies measuring oxygen saturation (SpO2) using pulse oximetry immediately after birth in term neonates have shown that it takes at least 5 minutes for preductal SpO2 to rise from ∼50% to >90%.2House J.T. Schultetus R.R. Gravenstein N. Continuous neonatal evaluation in the delivery room by pulse oximetry.J Clin Monit. 1987; 3: 96-100Crossref PubMed Scopus (83) Google Scholar, 3Kopotic R.J. Lindner W. Assessing high-risk infants in the delivery room with pulse oximetry.Anaesth Analg. 2002; 94: S31-S36PubMed Google Scholar, 6Dimich I. Singh P.P. Adell A. Hendler M. Sonnenklar N. Jhaveri M. Evaluation of oxygen saturation monitoring by pulse oximetry in neonates in the delivery room.Can J Anaesth. 1991; 38: 985-988Crossref PubMed Scopus (71) Google Scholar, 7Kamlin C.O. O'Donnell C.P. Davis P.G. Morley C.J. Oxygen saturation in healthy infants immediately after birth.J Pediatr. 2006; 148: 585-589Abstract Full Text Full Text PDF PubMed Scopus (180) Google Scholar, 8Rao R. Ramji S. Pulse oximetry in asphyxiated newborns in the delivery room.Indian Pediatr. 2001; 38: 762-766PubMed Google Scholar, 9Saugstad O.D. Oxygen saturations immediately after birth.J Pediatr. 2006; 148: 569-570Abstract Full Text Full Text PDF PubMed Scopus (43) Google Scholar, 10Saugstad O.D. Ramji S. Vento M. Resuscitation of depressed newborn infants with ambient air or pure oxygen: a meta-analysis.Biol Neonate. 2005; 87: 27-34Crossref PubMed Scopus (168) Google Scholar Preterm infants have slightly lower SpO2 than term infants in the first 10 minutes after birth.3Kopotic R.J. Lindner W. Assessing high-risk infants in the delivery room with pulse oximetry.Anaesth Analg. 2002; 94: S31-S36PubMed Google Scholar, 7Kamlin C.O. O'Donnell C.P. Davis P.G. Morley C.J. Oxygen saturation in healthy infants immediately after birth.J Pediatr. 2006; 148: 585-589Abstract Full Text Full Text PDF PubMed Scopus (180) Google Scholar, 11Dawson J.A. Kamlin C.O. Vento M. Wong C. Cole T.J. Donath S.M. et al.Defining the reference range for oxygen saturation for infants after birth.Pediatrics. 2010; 125: e1340-e1347Crossref PubMed Scopus (359) Google Scholar, 12Nuntnarumit P. Rojnueangnit K. Tangnoo A. Oxygen saturation trend in preterm infants during the first 15 min after birth.J Perinatol. 2009; 130: 399-402Google Scholar Our pulse oximetry findings from a cohort of 468 infants (25-42 weeks' gestation) who did not receive oxygen or other interventions in the delivery room are similar to those of others.1Altuncu E. Ozek E. Bilgen H. Topuzoglu A. Kavuncuoglu S. Percentiles of oxygen saturations in healthy term newborns in the first minutes of life.Eur J Pediatr. 2008; 167: 687-688Crossref PubMed Scopus (51) Google Scholar, 12Nuntnarumit P. Rojnueangnit K. Tangnoo A. Oxygen saturation trend in preterm infants during the first 15 min after birth.J Perinatol. 2009; 130: 399-402Google Scholar, 13Mariani G. Dik P.B. Ezquer A. Aguirre A. Esteban M.L. Perez C. et al.Pre-ductal and post-ductal O2 saturation in healthy term neonates after birth.J Pediatr. 2007; 150: 418-421Abstract Full Text Full Text PDF PubMed Scopus (138) Google Scholar, 14Meier-Stauss P. Bucher H.U. Hürlimann R. König V. Huch R. Pulse oximetry used for documenting oxygen saturation and right-to-left shunting immediately after birth.Eur J Pediatr. 1990; 149: 851-855Crossref PubMed Scopus (61) Google Scholar, 15Rabi Y. Yee W. Chen S.Y. Singhal N. Oxygen saturation trends immediately after birth.J Pediatr. 2006; 148: 590-594Abstract Full Text Full Text PDF PubMed Scopus (115) Google Scholar We used these data to construct charts illustrating the 10th-90th percentiles for SpO2 at 1-10 minutes after birth. The percentile lines represent the proportion of infants with SpO2 values below each percentile at each time point (Figure).11Dawson J.A. Kamlin C.O. Vento M. Wong C. Cole T.J. Donath S.M. et al.Defining the reference range for oxygen saturation for infants after birth.Pediatrics. 2010; 125: e1340-e1347Crossref PubMed Scopus (359) Google Scholar As shown, healthy newborn infants have a wide range of SpO2 values. In the neonatal intensive care unit (NICU), oxygen is administered in response to the infant's color, blood gas values, transcutaneous O2 monitoring, or SpO2 measured with a pulse oximeter. In most NICUs, the infant's fraction of inspired oxygen (FiO2) is adjusted to maintain SpO2 within a target range. This range may differ among NICUs, but the common goal is to avoid hypoxia and hyperoxia. The International Liaison Committee on Resuscitation's 2010 guidelines suggest using pulse oximetry to guide oxygen treatment in the delivery room16Field J.M. Hazinski M.F. Sayre M.R. Chameides L. Schexnayder S.M. Hemphill R. et al.Part 1, executive summary: 2010 American Heart Association Guidelines for cardiopulmonary resuscitation and emergency cardiovascular care.Circulation. 2010; 122: S640-S656Crossref PubMed Scopus (752) Google Scholar to avoid hyperoxia and hypoxia, particularly in extremely preterm infants. Suggested target pulse oximetry levels at intervals after birth have been provided.17Perlman J.M. Wyllie J. Kattwinkel J. Atkins D.L. Chameides L. Goldsmith J.P. et al.Part 11, neonatal resuscitation: 2010 international consensus on cardiopulmonary resuscitation and emergency cardiovascular care science with treatment recommendations.Circulation. 2010; 122: S516-S538Crossref PubMed Scopus (531) Google Scholar The practice of using 100% rather than 21% oxygen in the delivery room has been associated with increased neonatal mortality.18Rabi Y. Rabi D. Yee W. Room air resuscitation of the depressed newborn: a systematic review and meta-analysis.Resuscitation. 2007; 72: 353-363Abstract Full Text Full Text PDF PubMed Scopus (159) Google Scholar, 19Tan A. Schulze A. O'Donnell C.P. Davis P.G. Air versus oxygen for resuscitation of infants at birth.Cochrane Database Syst Rev. 2005; 2: CD002273PubMed Google Scholar Studies by Vento and coworkers20Vento M. Asensi M. Sastre J. Lloret A. García-Sala F. Viña J. Oxidative stress in asphyxiated term infants resuscitated with 100% oxygen.J Pediatr. 2003; 142: 240-246Abstract Full Text Full Text PDF PubMed Scopus (271) Google Scholar, 21Vento M. Asensi M. Sastre J. Lloret A. Garcia-Sala F. Minana J.B. et al.Hyperoxemia caused by resuscitation with pure oxygen may alter intracellular redox status by increasing oxidized glutathione in asphyxiated newly born infants.Semin Perinatol. 2002; 26: 406-410Abstract Full Text PDF PubMed Scopus (74) Google Scholar, 22Vento M. Moro M. Escrig R. Arruza L. Villar G. Izquierdo I. et al.Preterm resuscitation with low oxygen causes less oxidative stress, inflammation, and chronic lung disease.Pediatrics. 2009; 124: e439-e449Crossref PubMed Scopus (356) Google Scholar and Saugstad and coworkers23Saugstad O.D. Resuscitation with room air or with oxygen supplementation.Clin Perinatol. 1998; 25: 741-756PubMed Google Scholar, 24Saugstad O.D. Siddarth R. Rootwelt T. Vento M. Response to resuscitation of the newborn: early prognostic variables.Acta Paediatr. 2005; 94: 890-895Crossref PubMed Scopus (55) Google Scholar, 25Saugstad O.D. Oxidative stress in the newborn: a 30-year perspective.Biol Neonate. 2005; 88: 228-236Crossref PubMed Scopus (282) Google Scholar, 26Saugstad O.D. Rootwelt T. Aalen O. Resuscitation of asphyxiated newborn infants with room air or oxygen: an international controlled trial. The Resair 2 Study.Pediatrics. 1998; 102: e1Crossref PubMed Scopus (365) Google Scholar have shown that delivery of high oxygen concentrations during resuscitation is associated with short-term and long-term morbidity. A limitation of these trials and meta-analyses is that they enrolled mostly term or late-preterm newborns. Evidence from both RCTs4Rabi Y. Yee W. Chen S.Y. Singhal N. Oxygen saturation trends immediately after birth.J Pediatr. 2006; 148: 590-594Abstract Full Text Full Text PDF PubMed Scopus (175) Google Scholar, 27Escrig R. Luis A. Izquierdo I. Villar G. Gimeno A. Sáenz P. et al.Achievement of target oxygen saturation in extremely low gestational neonates resuscitated with different oxygen concentrations: a prospective randomized clinical trial.Pedatrics. 2008; 125: 875-881Crossref Scopus (183) Google Scholar, 28Ezaki S. Suzuki K. Kurishima C. Miura M. Weilin W. Hoshi R. et al.Resuscitation of preterm infants with reduced oxygen results in less oxidative stress than resuscitation with 100% oxygen.J Clin Biochem Nutr. 2009; 44: 111-118Crossref PubMed Scopus (48) Google Scholar, 29Harling A.E. Beresford M.W. Vince G.S. Bates M. Yoxall C.W. Does the use of 50% oxygen at birth in preterm infants reduce lung injury?.Arch Dis Child Fetal Neonatal Ed. 2005; 90: F401-F405Crossref PubMed Scopus (39) Google Scholar, 30Vento M. Asensi M. Sastre J. García-Sala F. Pallardó F.V. Viña J. Resuscitation with room air instead of 100% oxygen prevents oxidative stress in moderately asphyxiated term neonates.Pediatrics. 2001; 107: 642-647Crossref PubMed Scopus (339) Google Scholar, 31Vento M. Sastre J. Asensi M.A. Vina J. Room-air resuscitation causes less damage to heart and kidney than 100% oxygen.Am J Respir Crit Care Med. 2005; 172: 1393-1398Crossref PubMed Scopus (229) Google Scholar, 32Wang C.L. Anderson C. Leone T.A. Rich W. Govindaswami B. Finer N.N. Resuscitation of preterm neonates by using room air or 100% oxygen.Pediatrics. 2008; 121: 1083-1089Crossref PubMed Scopus (202) Google Scholar and observational studies33Dawson J.A. Kamlin C.O. Wong C. Te Pas A.B. O'Donnell C.P. Donath S.M. et al.Oxygen saturation and heart rate during delivery room resuscitation of infants <30 weeks' gestation with air or 100% oxygen.Arch Dis Child Fetal Neonatal Ed. 2009; 94: F87-F91Crossref PubMed Scopus (110) Google Scholar, 34Stola A. Schulman J. Perlman J. Initiating delivery room stabilization/resuscitation in very low birth weight (VLBW) infants with an FiO2 less than 100% is feasible.J Perinatol. 2009; 29: 548-552Crossref PubMed Scopus (18) Google Scholar suggests that preterm infants can be successfully treated in the delivery room with less than 100% oxygen. Two RCTs27Escrig R. Luis A. Izquierdo I. Villar G. Gimeno A. Sáenz P. et al.Achievement of target oxygen saturation in extremely low gestational neonates resuscitated with different oxygen concentrations: a prospective randomized clinical trial.Pedatrics. 2008; 125: 875-881Crossref Scopus (183) Google Scholar, 32Wang C.L. Anderson C. Leone T.A. Rich W. Govindaswami B. Finer N.N. Resuscitation of preterm neonates by using room air or 100% oxygen.Pediatrics. 2008; 121: 1083-1089Crossref PubMed Scopus (202) Google Scholar and 2 observational studies33Dawson J.A. Kamlin C.O. Wong C. Te Pas A.B. O'Donnell C.P. Donath S.M. et al.Oxygen saturation and heart rate during delivery room resuscitation of infants <30 weeks' gestation with air or 100% oxygen.Arch Dis Child Fetal Neonatal Ed. 2009; 94: F87-F91Crossref PubMed Scopus (110) Google Scholar, 34Stola A. Schulman J. Perlman J. Initiating delivery room stabilization/resuscitation in very low birth weight (VLBW) infants with an FiO2 less than 100% is feasible.J Perinatol. 2009; 29: 548-552Crossref PubMed Scopus (18) Google Scholar have shown that active management of FiO2 using pulse oximetry is possible and can prevent hyperoxia. Interestingly, even though these studies had different criteria for starting oxygen, they all demonstrated that most extremely preterm infants eventually require some supplemental oxygen in the delivery room.27Escrig R. Luis A. Izquierdo I. Villar G. Gimeno A. Sáenz P. et al.Achievement of target oxygen saturation in extremely low gestational neonates resuscitated with different oxygen concentrations: a prospective randomized clinical trial.Pedatrics. 2008; 125: 875-881Crossref Scopus (183) Google Scholar, 32Wang C.L. Anderson C. Leone T.A. Rich W. Govindaswami B. Finer N.N. Resuscitation of preterm neonates by using room air or 100% oxygen.Pediatrics. 2008; 121: 1083-1089Crossref PubMed Scopus (202) Google Scholar, 33Dawson J.A. Kamlin C.O. Wong C. Te Pas A.B. O'Donnell C.P. Donath S.M. et al.Oxygen saturation and heart rate during delivery room resuscitation of infants <30 weeks' gestation with air or 100% oxygen.Arch Dis Child Fetal Neonatal Ed. 2009; 94: F87-F91Crossref PubMed Scopus (110) Google Scholar, 34Stola A. Schulman J. Perlman J. Initiating delivery room stabilization/resuscitation in very low birth weight (VLBW) infants with an FiO2 less than 100% is feasible.J Perinatol. 2009; 29: 548-552Crossref PubMed Scopus (18) Google Scholar Many clinicians have experience in applying pulse oximeter sensors in the NICU. However, the delivery room is a challenging environment, and most operators find that their ability to obtain data quickly improves with experience. Data are most quickly available if the device is applied in the following order: (1) turn on the oximeter; (2) apply the sensor to the infant's right hand or wrist; (3) connect the sensor to the oximeter cable; and (4) shield the sensor from light.35O'Donnell C.P.F. Kamlin C.O.F. Davis P.G. Morley C.J. Feasibility of and delay in obtaining pulse oximetry during neonatal resuscitation.Pediatrics. 2005; 147: 698-699Abstract Full Text Full Text PDF Scopus (104) Google Scholar, 36O'Donnell C.P.F. Kamlin C.O.F. Davis P.G. Morley C.J. Obtaining pulse oximetry data in neonates: a randomised crossover study of sensor application techniques.Arch Dis Child Fetal Neonatal Ed. 2005; 90: F84-F85Crossref PubMed Scopus (69) Google Scholar The sensor is placed on the right hand or wrist to reflect the SpO2 of blood flow to the brain.14Meier-Stauss P. Bucher H.U. Hürlimann R. König V. Huch R. Pulse oximetry used for documenting oxygen saturation and right-to-left shunting immediately after birth.Eur J Pediatr. 1990; 149: 851-855Crossref PubMed Scopus (61) Google Scholar SpO2 measured from a foot is substantially lower than that measured in the right hand for many minutes after birth.13Mariani G. Dik P.B. Ezquer A. Aguirre A. Esteban M.L. Perez C. et al.Pre-ductal and post-ductal O2 saturation in healthy term neonates after birth.J Pediatr. 2007; 150: 418-421Abstract Full Text Full Text PDF PubMed Scopus (138) Google Scholar, 14Meier-Stauss P. Bucher H.U. Hürlimann R. König V. Huch R. Pulse oximetry used for documenting oxygen saturation and right-to-left shunting immediately after birth.Eur J Pediatr. 1990; 149: 851-855Crossref PubMed Scopus (61) Google Scholar The American Heart Association cautions the clinician against excessive use of oxygen, especially in preterm infants.37American Heart Association2005 American Heart Association (AHA) guidelines for cardiopulmonary resuscitation (CPR) and emergency cardiovascular care (ECC) of pediatric and neonatal patients: neonatal resuscitation guidelines.Pediatrics. 2006; 117: 1029-1038Crossref PubMed Scopus (195) Google Scholar There is agreement that hypoxia and hyperoxia should be prevented in newborn infants; however, an appropriate SpO2 target below which oxygen therapy does more good than harm during resuscitation has not yet been determined. The highest safe level of SpO2 also is unclear. Even short-term exposure to a high FiO2 can generate reactive oxygen and nitrogen species.21Vento M. Asensi M. Sastre J. Lloret A. Garcia-Sala F. Minana J.B. et al.Hyperoxemia caused by resuscitation with pure oxygen may alter intracellular redox status by increasing oxidized glutathione in asphyxiated newly born infants.Semin Perinatol. 2002; 26: 406-410Abstract Full Text PDF PubMed Scopus (74) Google Scholar, 31Vento M. Sastre J. Asensi M.A. Vina J. Room-air resuscitation causes less damage to heart and kidney than 100% oxygen.Am J Respir Crit Care Med. 2005; 172: 1393-1398Crossref PubMed Scopus (229) Google Scholar These free radicals are associated with short- and long-term morbidity, with preterm infants at greatest risk of harm from exposure to excess oxygen.21Vento M. Asensi M. Sastre J. Lloret A. Garcia-Sala F. Minana J.B. et al.Hyperoxemia caused by resuscitation with pure oxygen may alter intracellular redox status by increasing oxidized glutathione in asphyxiated newly born infants.Semin Perinatol. 2002; 26: 406-410Abstract Full Text PDF PubMed Scopus (74) Google Scholar, 25Saugstad O.D. Oxidative stress in the newborn: a 30-year perspective.Biol Neonate. 2005; 88: 228-236Crossref PubMed Scopus (282) Google Scholar, 31Vento M. Sastre J. Asensi M.A. Vina J. Room-air resuscitation causes less damage to heart and kidney than 100% oxygen.Am J Respir Crit Care Med. 2005; 172: 1393-1398Crossref PubMed Scopus (229) Google Scholar There are insufficient data from very preterm infants to develop gestational age–specific normal SpO2 ranges.3Kopotic R.J. Lindner W. Assessing high-risk infants in the delivery room with pulse oximetry.Anaesth Analg. 2002; 94: S31-S36PubMed Google Scholar, 7Kamlin C.O. O'Donnell C.P. Davis P.G. Morley C.J. Oxygen saturation in healthy infants immediately after birth.J Pediatr. 2006; 148: 585-589Abstract Full Text Full Text PDF PubMed Scopus (180) Google Scholar, 11Dawson J.A. Kamlin C.O. Vento M. Wong C. Cole T.J. Donath S.M. et al.Defining the reference range for oxygen saturation for infants after birth.Pediatrics. 2010; 125: e1340-e1347Crossref PubMed Scopus (359) Google Scholar To date, no RCT has indicated the appropriate SpO2 target range in the delivery room. In the American Heart Association's 2010 newborn resuscitation algorithm, the preductal SpO2 target ranges at 1, 2, 3, 4, 5, and 10 minutes after birth are 60%-65%, 65%-70%, 70%-75%, 75%-80%, 80%-85%, and 85%-95%, respectively.17Perlman J.M. Wyllie J. Kattwinkel J. Atkins D.L. Chameides L. Goldsmith J.P. et al.Part 11, neonatal resuscitation: 2010 international consensus on cardiopulmonary resuscitation and emergency cardiovascular care science with treatment recommendations.Circulation. 2010; 122: S516-S538Crossref PubMed Scopus (531) Google Scholar These values are close to the median values for infants who do not require resuscitation.11Dawson J.A. Kamlin C.O. Vento M. Wong C. Cole T.J. Donath S.M. et al.Defining the reference range for oxygen saturation for infants after birth.Pediatrics. 2010; 125: e1340-e1347Crossref PubMed Scopus (359) Google Scholar In contrast, the European Resuscitation Council's newborn life support algorithm recommends starting oxygen at an SpO2 of 60%, 70%, 80%, 85%, and 90% at 2, 3, 4, 5, and 10 minutes after birth, respectively. These values are closer to the 25th percentile11Dawson J.A. Kamlin C.O. Vento M. Wong C. Cole T.J. Donath S.M. et al.Defining the reference range for oxygen saturation for infants after birth.Pediatrics. 2010; 125: e1340-e1347Crossref PubMed Scopus (359) Google Scholar; however, the targets from both algorithms are sufficiently similar for practical use. There are several possible reasons for the differences in the American Heart Association– and European Resuscitation Council–recommended SpO2 levels for starting oxygen. First, there is no evidence to indicate whether SpO2 targets should be chosen based on saturation values measured in preterm infants not receiving medical interventions in the delivery room or those measured in their term counterparts. Second, the appropriate SpO2 percentile at which to commence oxygen supplementation has not been determined in RCTs. It is important to remember that if the 50th percentile is chosen, then 50% of normal infants will have a "low" SpO2. If the target SpO2 percentile is too low, then hypoxic damage may result. If the target SpO2 percentile is set too high, then clinicians will provide unnecessary oxygen treatment, possibly resulting in oxygen toxicity. Data from term infants who received no interventions in the delivery room were used to construct a normal range of SpO2 in the first 10 minutes after birth (Figure). A saturation-tracking system has been developed (W.R. at University of California San Diego) that displays real-time FiO2 and SpO2 values plotted against high and low SpO2 targets using a data acquisition system, an Excel chart, and a netbook computer. Clinical assessment of the infant is important before starting oxygen therapy. However, clinical assessment of color and heart rate are subjective and unreliable.38Dawson J.A. Kamlin C.O. Wong C. Te Pas A.B. Vento M. Cole T.J. et al.Changes in heart rate in the first minutes after birth.Arch Dis Child Fetal Neonatal Ed. 2010; 95: F177-F181Crossref PubMed Scopus (128) Google Scholar Many healthy infants do not appear pink until several minutes after birth; this is normal and does not mean that they need oxygen treatment. But an infant who is unresponsive, hypotonic, and bradycardic requires prompt intervention. Important signs of an infant's satisfactory transition regardless of the pulse oximetry measurements are a rising heart rate, improving muscle tone, and spontaneous breathing.16Field J.M. Hazinski M.F. Sayre M.R. Chameides L. Schexnayder S.M. Hemphill R. et al.Part 1, executive summary: 2010 American Heart Association Guidelines for cardiopulmonary resuscitation and emergency cardiovascular care.Circulation. 2010; 122: S640-S656Crossref PubMed Scopus (752) Google Scholar Oxygen treatment in a newborn infant will not be effective if the infant's lungs are not aerated and gas is unable to cross the alveolar epithelium. The first step in improving oxygenation is not oxygen treatment, but rather lung aeration and establishment of a functional residual capacity.39Crossley K.J. Morley C.J. Allison B.J. Polglase G.R. Dargaville P.A. Harding R. et al.Blood gases and pulmonary blood flow during resuscitation of very preterm lambs treated with antenatal betamethasone and/or Curosurf: effect of positive end-expiratory pressure.Pediatr Res. 2007; 62: 37-42Crossref PubMed Scopus (29) Google Scholar, 40Probyn M.E. Hooper S.B. Dargaville P.A. McCallion N. Crossley K. Harding R. et al.Positive end expiratory pressure during resuscitation of premature lambs rapidly improves blood gases without adversely affecting arterial pressure.Pediatr Res. 2004; 56: 198-204Crossref PubMed Scopus (99) Google Scholar, 41Siew M.L. Te Pas A.B. Wallace M.J. Kitchen M.J. Lewis R.A. Fouras A. et al.Positive end-expiratory pressure enhances development of a functional residual capacity in preterm rabbits ventilated from birth.J Appl Physiol. 2009; 106: 1487-1493Crossref PubMed Scopus (115) Google Scholar, 42Te Pas A.B. Siew M. Wallace M.J. Kitchen M.J. Fouras A. Lewis R.A. et al.Establishing functional residual capacity at birth: the effect of sustained inflation and positive end-expiratory pressure in a preterm rabbit model.Pediatr Res. 2009; 65: 537-541Crossref PubMed Scopus (146) Google Scholar The most effective way to achieve this is with continuous positive airway pressure (CPAP) if the infant is breathing but has respiratory difficulty. If the infant is not breathing adequately, then intermittent positive-pressure ventilation with positive end-expiratory pressure (PEEP) should be used. According to the International Liaison Committee on Resuscitation, PEEP is likely to be beneficial during the initial stabilization of apneic preterm infants who require intermittent positive-pressure ventilation and should be used if the necessary equipment is available.17Perlman J.M. Wyllie J. Kattwinkel J. Atkins D.L. Chameides L. Goldsmith J.P. et al.Part 11, neonatal resuscitation: 2010 international consensus on cardiopulmonary resuscitation and emergency cardiovascular care science with treatment recommendations.Circulation. 2010; 122: S516-S538Crossref PubMed Scopus (531) Google Scholar The most reliable device for providing CPAP or PEEP in the delivery room is a T-piece resuscitator. A self-inflating bag fitted with a PEEP valve can provide PEEP during ventilation, but the PEEP delivered is variable. Self-inflating bags cannot be used to deliver CPAP.43Klingenberg C. Dawson J.A. Gerber A. Kamlin C.O. Davis P.G. Morley C.J. Sustained inflations: comparing three neonatal resuscitation devices.Neonatology. 2011; 100: 78-84Crossref PubMed Scopus (34) Google Scholar, 44Morley C.J. Dawson J.A. Stewart M.J. Hussain F. Davis P.G. The effect of a PEEP valve on a Laerdal neonatal self-inflating resuscitation bag.J Paediatr Child Health. 2010; 46: 51-56Crossref PubMed Scopus (44) Google Scholar A flow-inflating bag can be used, but the CPAP or PEEP delivered via these modalities is highly variable and depends on the experience of the resuscitator. The initial stabilization and assessment of the newborn preterm infant should be directed at warming the infant and assessing breathing and heart rate. A pulse oximeter should be applied to the infant's right wrist as soon as possible after birth. If the infant has a rising heart rate and SpO2 and is breathing well, then supportive management should be continued. Many normal babies infant's may not start effective breathing until at least a minute after birth. If continuous heart rate measurement is not available, then the infant should be assessed clinically at least every 30 seconds after birth. In an infant with a heart rate 90% (Figure). Because SpO2 >95% may be associated with unpredictably high arterial oxygen concentration, supplemental oxygen should be reduced to maintain SpO2 <96% at all times in the delivery room. Using pulse oximetry to determine the appropriate level of respiratory support and to guide the decision of whether or not to provide oxygen is not evidence-based practice. RCTs comparing different SpO2 target ranges are urgently needed. These trials should measure long-term neurodevelopment as their primary outcome. The Targeted Oxygenation in the Resuscitation of Premature Infants and Their Developmental Outcome trial (TO2RPIDO) is recruiting infants at ≤31 weeks' gestation to compare 100% oxygen and air as the initial gas for resuscitation, using SpO2 targeting. For the air group, FiO2 is increased if SpO2 is <65% by 5 minutes, <80% at 5-10 minutes, and 92%. The Premature Infants Resuscitation with Oxygen or Air trial, currently in the planning stage, is a blinded comparison of a targeted oxygen strategy comparing the initial use of 21% oxygen and 90% oxygen. Effective ventilation is required before alterations to oxygen therapy can be considered. While we await higher quality evidence, the SpO2 centile charts represent our best estimate of the most appropriate SpO2 targets for preterm infants during the first minutes after birth. Local strategies for managing oxygen therapy in the delivery room will be influenced by the available equipment, the experience of the staff attending deliveries, and the patient mix at the individual institution.
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