A G De Paoli1, P G Davis, B Faber, C J Morley. 1. Neonatal Unit, Royal Women's Hospital, 132 Grattan St, Carlton, Melbourne, Victoria, Australia, 3053. depaolit@cryptic.rch.unimelb.edu.au
Abstract
BACKGROUND: Nasal continuous positive airway pressure (NCPAP) is used to support preterm infants recently extubated, those experiencing significant apnoea of prematurity and those with respiratory distress soon after birth as an alternative to intubation and ventilation. This review will focus exclusively on identifying the most effective pressure source and interface for NCPAP delivery in preterm infants. OBJECTIVES: In preterm infants extubated to NCPAP following intermittent positive pressure ventilation (IPPV) for respiratory distress syndrome (RDS) or in those treated with NCPAP soon after birth, which technique of pressure generation and which type of nasal interface for NCPAP delivery most effectively reduces the need for additional respiratory support? SEARCH STRATEGY: The strategy included searches of MEDLINE (1966-2002), the Cochrane Controlled Trials Register (The Cochrane Library, Issue 1, 2002), CINAHL, abstracts from conference proceedings, cross-referencing of previous reviews and the use of expert informants. SELECTION CRITERIA: Randomised or quasi-randomised trials comparing different techniques of NCPAP pressure generation and/or nasal interfaces in preterm infants extubated to NCPAP following IPPV for RDS or treated with NCPAP soon after birth. DATA COLLECTION AND ANALYSIS: Data was extracted and analysed by the first three authors. Dichotomous results were analysed using the relative risk (RR), risk difference (RD) and number needed to treat (NNT). MAIN RESULTS: 1. Preterm infants being extubated to NCPAP following a period of IPPV for RDS: Meta-analysis of the results from Davis 2001 and Roukema 1999a demonstrated that short binasal prongs are more effective at preventing re-intubation than single nasal or nasopharyngeal prongs [typical RR 0.59 (CI: 0.41, 0.85), typical RD -0.21 (CI: -0.35, -0.07), NNT 5 (CI: 3, 14)]. In the single study comparing short binasal prong devices (Sun 1999) the re-intubation rate was significantly lower with the Infant Flow Driver than with the Medicorp prong [RR 0.33 (CI: 0.17, 0.67), RD -0.32 (CI: -0.49, -0.15), NNT 3 (CI: 2, 7)]. 2. Preterm infants primarily treated with NCPAP soon after birth: The one trial identified, Mazzella 2001, found a significantly lower oxygen requirement and respiratory rate in those randomised to short binasal prongs when compared with CPAP delivered via nasopharyngeal prong. The requirement for intubation beyond 48 hours from randomisation was not assessed. No studies comparing different techniques of pressure generation were identified. REVIEWER'S CONCLUSIONS: Short binasal prong devices are more effective than single prongs in reducing the rate of re-intubation. Although the Infant Flow Driver appears more effective than Medicorp prongs the most effective short binasal prong device remains to be determined. The improvement in respiratory parameters with short binasal prongs suggests they are more effective than nasopharyngeal CPAP in the treatment of early RDS. Further studies incorporating longer-term outcomes are required. Studies are also needed to determine the optimal pressure source for the delivery of NCPAP.
BACKGROUND: Nasal continuous positive airway pressure (NCPAP) is used to support preterm infants recently extubated, those experiencing significant apnoea of prematurity and those with respiratory distress soon after birth as an alternative to intubation and ventilation. This review will focus exclusively on identifying the most effective pressure source and interface for NCPAP delivery in preterm infants. OBJECTIVES: In preterm infants extubated to NCPAP following intermittent positive pressure ventilation (IPPV) for respiratory distress syndrome (RDS) or in those treated with NCPAP soon after birth, which technique of pressure generation and which type of nasal interface for NCPAP delivery most effectively reduces the need for additional respiratory support? SEARCH STRATEGY: The strategy included searches of MEDLINE (1966-2002), the Cochrane Controlled Trials Register (The Cochrane Library, Issue 1, 2002), CINAHL, abstracts from conference proceedings, cross-referencing of previous reviews and the use of expert informants. SELECTION CRITERIA: Randomised or quasi-randomised trials comparing different techniques of NCPAP pressure generation and/or nasal interfaces in preterm infants extubated to NCPAP following IPPV for RDS or treated with NCPAP soon after birth. DATA COLLECTION AND ANALYSIS: Data was extracted and analysed by the first three authors. Dichotomous results were analysed using the relative risk (RR), risk difference (RD) and number needed to treat (NNT). MAIN RESULTS: 1. Preterm infants being extubated to NCPAP following a period of IPPV for RDS: Meta-analysis of the results from Davis 2001 and Roukema 1999a demonstrated that short binasal prongs are more effective at preventing re-intubation than single nasal or nasopharyngeal prongs [typical RR 0.59 (CI: 0.41, 0.85), typical RD -0.21 (CI: -0.35, -0.07), NNT 5 (CI: 3, 14)]. In the single study comparing short binasal prong devices (Sun 1999) the re-intubation rate was significantly lower with the Infant Flow Driver than with the Medicorp prong [RR 0.33 (CI: 0.17, 0.67), RD -0.32 (CI: -0.49, -0.15), NNT 3 (CI: 2, 7)]. 2. Preterm infants primarily treated with NCPAP soon after birth: The one trial identified, Mazzella 2001, found a significantly lower oxygen requirement and respiratory rate in those randomised to short binasal prongs when compared with CPAP delivered via nasopharyngeal prong. The requirement for intubation beyond 48 hours from randomisation was not assessed. No studies comparing different techniques of pressure generation were identified. REVIEWER'S CONCLUSIONS: Short binasal prong devices are more effective than single prongs in reducing the rate of re-intubation. Although the Infant Flow Driver appears more effective than Medicorp prongs the most effective short binasal prong device remains to be determined. The improvement in respiratory parameters with short binasal prongs suggests they are more effective than nasopharyngeal CPAP in the treatment of early RDS. Further studies incorporating longer-term outcomes are required. Studies are also needed to determine the optimal pressure source for the delivery of NCPAP.