Correspondence
Nasal CPAP for Very Preterm Infants
N Engl J Med 2008; 358:2520-2521June 5, 2008
- Article
To the Editor:
In the trial reported by Morley et al. (Feb. 14 issue),1 a significant reduction in the use of surfactant in the group treated with early continuous positive airway pressure (CPAP) as compared with the intubation group (38% vs. 77%) was perhaps the most striking finding. In the CPAP group, the median time for intubation was 6.6 hours (interquartile range, 2.2 to 19.3), and we inferred from this that surfactant was probably given as a rescue treatment. Since the timing of surfactant therapy is likely to affect outcome measures,2 perhaps the advantages of early CPAP balanced out the advantages of early surfactant treatment in the intubation group. To address this question, a detailed comparison of the timing of surfactant treatment in both groups would be of interest.
2 ReferencesRalph K.H. Nanan, Ph.D.
Anthony J.W. Liu, M.B., B.S., M.P.H.
Alison Poulton, M.B., B.Chir.
University of Sydney, Penrith, NSW 2750, Australia
ralphn@med.usyd. edu. au 1
Morley CJ ,Davis PG ,Doyle LW ,Brion LP ,Hascoet J-M ,Carlin JB . Nasal CPAP or intubation at birth for very preterm infants. N Engl J Med 2008;358:700-708[Erratum, N Engl J Med 2008;358:1529.]
Full Text | Web of Science | Medline2
Stevens TP ,Harrington EW ,Blennow M ,Soll RF . Early surfactant administration with brief ventilation vs. selective surfactant and continued mechanical ventilation for preterm infants with or at risk for respiratory distress syndrome. Cochrane Database Syst Rev 2007;4:CD003063-CD003063
Medline
To the Editor:
Morley et al. found that early CPAP did not significantly reduce the rate of bronchopulmonary dysplasia, but as compared with infants in the intubation group, fewer infants in the CPAP group received oxygen at 28 days, and they had fewer days of ventilation.1 However, there was no reference to whether chorioamnionitis was an antenatal risk factor for bronchopulmonary dysplasia in these patients.2 We would be interested to know whether there was a relationship between an antenatal diagnosis of chorioamnionitis and the outcomes.
2 ReferencesVincenzo Zanardo, M.D.
Daniele Trevisanuto, M.D.
Silvia Chiarelli, M.D.
Padua University School of Medicine, 35128 Padua, Italy
zanardo@pediatria.unipd. it 1
Jobe AH ,Ikegami M . Antenatal infection/inflammation and postnatal lung maturation and injury. Respir Res 2001;2:27-32
CrossRef | Web of Science | Medline2
Watterberg KL ,Demers LM ,Scott SM ,Murphy S . Chorioamnionitis and early lung inflammation in infants in whom bronchopulmonary dysplasia develops. Pediatrics 1996;97:210-215
Web of Science | Medline
To the Editor:
When receiving air at above atmospheric pressure through nasal prongs, a baby has to breathe out against both increased pressure and increased resistance. While nasal prongs are being used, handling of the baby or his or her crying may cause an abrupt change in alveolar pressure. The association of pneumothorax with CPAP may be related to these factors rather than to “airway” pressures measured outside the baby. A mask might carry less risk than prongs.
Tom Hughes-Davies, F.R.C.P.
Breamore Marsh, Fordingbridge SP6 2EJ, United Kingdom
thhd@thhd.fsnet. co. uk Author/Editor Response
In response to Nanan et al., infants in the Continuous Positive Airway Pressure or Intubation at Birth (COIN) trial who were randomly assigned to CPAP treatment after birth were not intubated specifically for surfactant treatment. They received surfactant only if they were intubated and ventilated, and surfactant was administered according to local protocols. We collected data only on whether surfactant was given — not on the timing of surfactant therapy after birth — so we cannot answer this question.
With regard to the comments by Zanardo and colleagues, data on chorioamnionitis were not collected for three reasons. First, the trial was started before we knew that chorioamnionitis might be important. Second, since diagnosing chorioamnionitis is subjective or depends on placental histologic findings, we decided it would be impractical to collect this information for all infants. Third, the COIN study was a randomized trial, and there was no reason to believe that the rate of chorioamnionitis would differ between the groups.
In response to Hughes-Davies, there is no clinical evidence that infants treated with nasal CPAP exhale through the CPAP prongs. As Hughes-Davies suggests, this would mean that they would breathe out against increased pressure and resistance. Our experience is that infants treated with nasal CPAP breathe out through their mouths or around the prongs. With face-mask CPAP and intubation, infants who undergo mechanical ventilation would be forced to breathe out against the pressure. It is therefore unclear why infants treated with a nasal mask would have lower rates of pneumothorax than those treated with nasal prongs.
Colin J. Morley, M.D.
Peter G. Davis, M.D.
Lex W. Doyle, M.D.
Royal Women's Hospital, Carlton, VIC 3053, Australia
colin.morley@rwh. org. au
