No evidence for superiority of air or oxygen for neonatal resuscitation: a meta-analysis

Abstract

Purpose The aim of this meta-analysis was to re-evaluate the evidence in favour of oxygen or room air as the initial gas mixture for neonatal resuscitation in terms of the following outcomes: death, hypoxic/ischemic encephalopathy, need for tracheal intubation, and APGAR score-Appearance (skin color), Pulse (heart rate), Grimace (reflex irritability), Activity (muscle tone), and Respiration-at five minutes. Methods A search with no language restriction for all available controlled clinical trials (CCT) was conducted in PUBMED, Cochrane Central Register of Controlled Trials, and EMBASE. Data were extracted independently by the two investigators. Results Eight CCTs were retained for analysis. They included 1,500 patients, 772 in the oxygen group and 728 in the air group. The evidence is based mainly on quasirandomized studies (1,311/1,500) with unblinded resuscitators (1,421/1,500). The expertise/training of the resuscitators was unspecified for four of the eight studies. The risk ratio (RR) for death was 1.35 (95% confidence intervals [CI] = 0.97 to 1.88; P = 0.08; I-squared 0%). The RR for hypoxic/ischemic encephalopathy was 1.03 (95% CI = 0.86 to 1.23; P = 0.74; I-squared 0%). The RR for requiring a tracheal intubation was 0.85 (95% CI = 0.69 to 1.05 [random effects model]; P = 0.12; I-squared = 9.51%). Conclusions The literature is insufficient to make any statement regarding the superiority of oxygen or room air as the initial gas mixture for neonatal resuscitation. RésuméObjectif L'objectif de cette me´ta-analyse e´tait de re´e´valuer les donne´es probantes soutenant la supe´riorited e l'oxyge`ne ou de l'air ambiant en tant que me´lange gazeux initial pour la re´animation ne´onatale en termes des crite`res suivants : de´ce`s, ence´phalopathie hypoxique / ische´mique, besoin d'intubation trache´ale et score APGAR -Apparence (couleur de la peau), Pouls (fre´quence cardiaque), Grimace (irritabilite´re´flexe), Activite´(tonus musculaire) et Respiration -a`cinq minutes.

Oxygen metabolism and oxygenation of the newborn

“…Initially only term and late preterm infants were studied. Meta-analyses including more than 2000 infants clearly showed a typical reduction in mortality of about 30% favoring air instead of oxygen [26][27][28][29][30]. It also became clear the use of 100% oxygen for newborn resuscitation triggered inflammation in a number of organs as the brain, heart and kidney [31][32][33], increased the risk of pulmonary hypertension [34,35], and was even associated with childhood cancer, especially leukemia [36,37].…”

Resuscitating preterm infants with 100% oxygen is associated with higher oxidative stress than room air

“…feasible, but information about long-term clinical outcomes (3,4) remains unsubstantiated (6,7). In addition, the use of room air for a prolonged period, such as more than two or three minutes, leads to hypoxia.…”

Targeted Oxygen in the Resuscitation of Preterm Infants, a Randomized Clinical Trial

“…8 Most infants, however, were recruited from developing countries, 3,4 and because RA resuscitation did not make a difference to 2-year neurodevelopmental outcomes, 9 the applicability for using RA in developed countries with different resuscitation resources is therefore unclear. 10 Even less clear is the evidence for using less O 2 to stabilize preterm infants. Preterm infants, in contrast to term infants, may need supplemental O 2 11 because of lung immaturity, but antioxidant defenses are also suboptimal until the third trimester.…”