Background: The application of a continuous distending pressure (CDP) has been shown to have some benefits in the treatment of pre-term infants with respiratory distress syndrome (RDS). CDP has the potential to reduce lung damage, particularly if applied early before atelectasis has occurred. Early application of CDP may better conserve an infant's own surfactant stores and consequently be more effective than CDP applied later in the course of RDS.
Objectives: In pre-term infants with RDS to determine if early compared with delayed initiation of CDP results in lower mortality and reduced need for intermittent positive pressure ventilation.
Search strategy: The standard search strategy of the Cochrane Neonatal Review Group was used. This included searches of the Oxford Database of Perinatal Trials, Cochrane Controlled Trials Register (Issue 1, 2002), MEDLINE (1966-2001), previous reviews including cross references, abstracts, conference and symposia proceedings, expert informants, journal hand searching mainly in the English language.
Selection criteria: Trials among pre-term infants with respiratory distress syndrome spontaneously breathing at trial entry, which used random or quasi-random allocation to either early or delayed CDP.
Data collection and analysis: Standard methods of the Cochrane Collaboration and its Neonatal Review Group were used, including independent assessment of trial quality and extraction of data by two authors.
Main results: In six studies on a total of 165 infants, early CDP was associated with a significant reduction in subsequent use of intermittent positive pressure ventilation, typical RR 0.55, RD -0.16, NNT 6, but there was no evidence of effect on overall mortality. There was no evidence of effect on the rates of pneumothorax (five studies) or bronchopulmonary dysplasia (one study). Early CDP resulted in a reduction in duration of oxygen therapy in the single study reporting this outcome.
Reviewer's conclusions: Early application of CDP has a clinical benefit in the treatment of RDS in that it reduces subsequent use of IPPV and thus may be useful in preventing the adverse effects of this treatment. However, many of the trials were done in the 1970s and 1980s and re-evaluation of the strategy of early CDP in the era of antenatal steroid use and early surfactant administration is indicated.