Question

• A 3kg, full-term infant, apneic at birth with a heart rate < 80 beats per minute is resuscitated with room air. Is this therapy superior to the traditional method of resuscitation with 100% oxygen?

Clinical Bottom Lines

1. Birth asphyxia is a common problem worldwide.
2. Resuscitation following birth asphyxia is traditionally carried out with 100% oxygen.
3. Resuscitation with high oxygen concentrations could have detrimental effects (1,2,3).
4. No randomized, controlled double-blinded studies comparing the resuscitation of asphyxiated newborns with room air versus 100% oxygen exist.
5. In a multicenter, prospective, controlled trial there was no significant reduction in neonatal mortality or primary outcome measures (1).
6. Apgar scores at 1 minute were significantly lower, time to first cry and first breath were significantly longer in the oxygen resuscitated group (1).

Summary of Key Evidence

1. 609 infants from 10 centers were randomized according to dates to the room air or oxygen group with 288 in the room air group and 321 in the oxygen group. Both groups had similar characteristics at the onset (1).
2. Primary outcome measures were death within 1 week and/or the presence of HIE (grade II or III). Death after 28 days was also reported. Secondary outcome measures were Apgar scores at 5 minutes, heart rate at 90 seconds, time to first breath, time to first cry, duration of resuscitation, arterial blood gases and acid base status at 10 and 30 minutes of age, and abnormal neurologic exam after 4 weeks. Analysis was based on an intention to treat basis (1).
3. No significant differences were found between neonatal mortality or primary outcome measures between the two groups. Mortality in the first 7 days of life was 12.2% in the room air and 15% in the oxygen group (OR= 0.82 with 95% CI =0.50-1.35). Death within 7 days and/or moderate to severe HIE was 21.2% in the room air group and 23.7% in the oxygen group (OR= 0.94 with 95% CI= 0.63-1.40) (1).
4. Apgar scores at 1 minute were significantly higher in the room air versus the oxygen group, but at 5 minutes there were no significant differences (with 8 (4-9) in room air group and 7 (3-9) in the oxygen group. Median time to first breath was 1.1 (1.0-1.2 minutes) in the room air group versus 1.5 (1.4-1.6 minutes). Median time to first cry was also 0.4 min shorter in the room air group. There was no difference in the other secondary outcome measures (1).
5. This study did not demonstrate significantly improved survival implementing room air instead of 100% oxygen in the resuscitation of newborn infants (1).

Additional Comments

• Entry criterion was apnea or gasping with heart rate < 80 beats per minute at birth (1).
• Exclusion criteria were BW < 1000g, lethal anomalies, hydrops, cyanotic heart defects, and stillbirths (1).
• The study was not blinded.
• Newborns were allocated to the treatment group according to date of birth; those born on even dates were treated with room air while those born on odd dates were treated with 100% oxygen (1).
• Informed consent was obtained after the initial resuscitation (1).
• This study took place primarily in developing countries (1).
• Differences in long-term neurologic outcomes are not known at this time, but follow-up is underway (1).

Citation

1. Saugstad OD. Roowelt T Aalen O. Resuscitation of asphyxiated newborn infants with room air or oxygen: an international controlled trial: the Resair 2 study. Pediatrics 1998; 102 (1):el..
2. Ramji S. Ahuja S. Thirupuram S. Rootwelt T. Rooth G. Saugstad OD. Resuscitation of asphyxic newborn infants with room air or 100% oxygen. Pediatric Research 1993; 34(6):809-12.
3. Saugstad OD. Resuscitation with room air or oxygen supplementation. Clinics in Perinatology 1998; 25(3):741-56.

CAT Author: Paola Fliman , MD

CAT Appraisers: Katherine Layton, MD

Date appraised: October 18, 2000