Background: Previous randomised trials and meta-analyses have shown nasal continuous positive airway pressure (NCPAP) to be a useful method of respiratory support after extubation. However, infants managed in this way sometimes "fail" and require endotracheal reintubation with its attendant risks and expense. Nasal intermittent positive pressure ventilation (NIPPV) is a method of augmenting NCPAP by delivering ventilator breaths via the nasal prongs. Older children and adults with chronic respiratory failure have been shown to benefit from NIPPV and the technique has been applied to neonates. However severe side effects including gastric perforation have been reported and clinicians remain uncertain about the role of NIPPV in neonatology. It has recently become possible to synchronise delivery of NIPPV with the infant's own breathing efforts which may make the modality more useful in this patient group.
Objectives: To determine whether the use of NIPPV as compared to NCPAP, in the preterm infant extubated following a period of intermittent positive pressure ventilation, decreases the rate of extubation failure without adverse effects.
Search strategy: Medline was searched using the MeSH terms: Infant, Newborn (exp) and Positive-pressure respiration (exp). Other sources included the Cochrane Controlled Trials Register, CINAHL using search terms: Infant, newborn and intermittent positive pressure ventilation, expert informants, previous reviews including cross-references and conference and symposia proceedings were used.
Selection criteria: Randomised trials comparing the use of NIPPV with NCPAP in preterm infants being extubated were selected for this review.
Data collection and analysis: Data regarding clinical outcomes including extubation failure, endotracheal reintubation, rates of apnea, gastrointestinal perforation, feeding intolerance, chronic lung disease and duration of hospital stay were extracted independently by the three reviewers. The trials were analysed using relative risk (RR), risk difference (RD) and number needed to treat (NNT) for dichotomous outcomes and weighted mean difference (WMD) for continuous outcomes.
Main results: Three trials comparing extubation of infants to NIPPV or to NCPAP were identified. All trials used the synchronised form of NIPPV. Each showed a statistically significant benefit for infants extubated to NIPPV in terms of prevention of extubation failure criteria. The meta-analysis shows the effect is also clinically important [RR 0.21 (0.10, 0.45), RD -0.32 (-0.45, -0.20), NNT 3 (2, 5)]. There were no reports of gastrointestinal perforation in any of the trials. Differences in rates of chronic lung disease approached but did not achieve statistical significance favouring NIPPV [RR 0.73 (0.49, 1.07), RD -0.15 (-0.33, 0.03)].
Implications for practice: NIPPV is a useful method of augmenting the beneficial effects of NCPAP in preterm infants. Its use reduces the incidence of symptoms of extubation failure more effectively than NCPAP. Within the limits of the small numbers of infants randomised to NIPPV there is a reassuring absence of the gastrointestinal side effects that were reported in previous case series.
Implications for research: Future trials should enrol sufficient infants to detect differences in important outcomes such as chronic lung disease and gastrointestinal perforation. The impact of synchronisation of NIPPV on the technique's safety and efficacy should be established in future trials.