Randomized control trial comparing physiologic effects in preterm infants during treatment with nasal continuous positive airway pressure (NCPAP) generated by Bubble NCPAP and Ventilator NCPAP: a pilot study

Bubble devices versus other pressure sources for nasal continuous positive airway pressure in preterm infants

BACKGROUND

Several types of pressure sources, including underwater bubble devices, mechanical ventilators, and the Infant Flow Driver, are used for providing continuous positive airway pressure (CPAP) to preterm infants with respiratory distress. It is unclear whether the use of bubble CPAP versus other pressure sources is associated with lower rates of CPAP treatment failure, or mortality and other morbidity.  OBJECTIVES: To assess the benefits and harms of bubble CPAP versus other pressure sources (mechanical ventilators or Infant Flow Driver) for reducing treatment failure and associated morbidity and mortality in newborn preterm infants with or at risk of respiratory distress.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2023, Issue 1); MEDLINE (1946 to 6 January 2023), Embase (1974 to 6 January 2023), Maternity & Infant Care Database (1971 to 6 January 2023), and the Cumulative Index to Nursing and Allied Health Literature (1982 to 6 January 2023). We searched clinical trials databases and the reference lists of retrieved articles.

SELECTION CRITERIA

We included randomised controlled trials comparing bubble CPAP with other pressure sources (mechanical ventilators or Infant Flow Driver) for the delivery of nasal CPAP to preterm infants.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Two review authors separately evaluated trial quality, extracted data, and synthesised effect estimates using risk ratio (RR), risk difference (RD), and mean difference. We used the GRADE approach to assess the certainty of the evidence for effects on treatment failure, all-cause mortality, neurodevelopmental impairment, pneumothorax, moderate-severe nasal trauma, and bronchopulmonary dysplasia.

MAIN RESULTS

We included 15 trials involving a total of 1437 infants. All trials were small (median number of participants 88). The methods used to generate the randomisation sequence and ensure allocation concealment were unclear in about half of the trial reports. Lack of measures to blind caregivers or investigators was a potential source of bias in all of the included trials. The trials took place during the past 25 years in care facilities internationally, predominantly in India (five trials) and Iran (four trials). The studied pressure sources were commercially available bubble CPAP devices versus a variety of mechanical ventilator (11 trials) or Infant Flow Driver (4 trials) devices.  Meta-analyses suggest that the use of bubble CPAP compared with mechanical ventilator or Infant Flow Driver CPAP may reduce the rate of treatment failure (RR 0.76, 95% confidence interval (CI) 0.60 to 0.95; (I² = 31%); RD -0.05, 95% CI -0.10 to -0.01; number needed to treat for an additional beneficial outcome 20, 95% CI 10 to 100; 13 trials, 1230 infants; low certainty evidence). The type of pressure source may not affect mortality prior to hospital discharge (RR 0.93, 95% CI 0.64 to 1.36 (I² = 0%); RD -0.01, 95% CI -0.04 to 0.02; 10 trials, 1189 infants; low certainty evidence). No data were available on neurodevelopmental impairment. Meta-analysis suggests that the pressure source may not affect the risk of pneumothorax (RR 0.73, 95% CI 0.40 to 1.34 (I² = 0%); RD -0.01, 95% CI -0.03 to 0.01; 14 trials, 1340 infants; low certainty evidence). Bubble CPAP likely increases the risk of moderate-severe nasal injury (RR 2.29, 95% CI 1.37 to 3.82 (I² = 17%); RD 0.07, 95% CI 0.03 to 0.11; number needed to treat for an additional harmful outcome 14, 95% CI 9 to 33; 8 trials, 753 infants; moderate certainty evidence). The pressure source may not affect the risk of bronchopulmonary dysplasia (RR 0.76, 95% CI 0.53 to 1.10 (I² = 0%); RD -0.04, 95% CI -0.09 to 0.01; 7 trials, 603 infants; low certainty evidence).  AUTHORS' CONCLUSIONS: Given the low level of certainty about the effects of bubble CPAP versus other pressure sources on the risk of treatment failure and most associated morbidity and mortality for preterm infants, further large, high-quality trials are needed to provide evidence of sufficient validity and applicability to inform context- and setting-relevant policy and practice.

Bubble versus other continuous positive airway pressure forms: a systematic review and meta-analysis

BACKGROUND

Use of bubble continuous positive airway pressure (CPAP) has generated considerable interest in neonatal care, but its comparative effectiveness compared with other forms of CPAP, especially in developed countries, remains unclear.

OBJECTIVE

To systematically review and meta-analyse short-term clinical outcomes among preterm infants treated with bubble CPAP vs all other forms of CPAP.

METHODS

Prospective experimental studies published from 1995 onward until October 2018 comparing bubble versus other CPAP forms in preterm neonates <37 weeks' gestational age were included after a systematic review of multiple databases using pre-specified search criteria.

RESULTS

A total of 978 articles were identified, of which 19 articles were included in meta-analyses. Of these, 5 had a high risk of bias, 8 had unclear risk and 6 had low risk. The risk of the primary outcome (CPAP failure within 7 days) was lower with bubble CPAP (0.75; 95% CI 0.57 to 0.98; 12 studies, 1194 subjects, I²=21%). Among secondary outcomes, only nasal injury was higher with use of bubble CPAP (risk ratio (RR) 2.04, 95% CI 1.33 to 3.14; 9 studies, 983 subjects; I²=42%) whereas no differences in mortality (RR 0.82, 95% CI 0.47 to 1.92; 9 studies, 1212 subjects, I²=20%) or bronchopulmonary dysplasia (BPD) (RR 0.8, 95% CI 0.53 to 1.21; 8 studies, 816 subjects, I²=0%) were noted.

CONCLUSION

Bubble CPAP may lead to lower incidence of CPAP failure compared with other CPAP forms. However, it does not appear to translate to improvement in mortality or BPD and potential for nasal injury warrants close monitoring during clinical application.

TRIAL REGISTRATION NUMBER

CRD42019120411.

Evidence Regarding the Use of Bubble Continuous Positive Airway Pressure in the Extremely Low Birth-Weight Infant: Benefits, Challenges, and Implications for Nursing Practice

BACKGROUND

Gentle ventilation with optimal oxygenation is integral to prevention of chronic lung disease in the extremely low birth-weight (ELBW) infant. Various types of noninvasive ventilation are used in neonatal intensive care units worldwide. Bubble continuous positive airway pressure (BCPAP) has been in use in newborn intensive care since 1975.

PURPOSE

To synthesize the current evidence on the use of BCPAP in the ELBW infant and its relationship to outcomes, particularly morbidity and mortality.

METHODS/SEARCH STRATEGIES

A literature review was completed using PubMed, EMBASE, CINAHL, and Cochrane with a focus on BCPAP use in the ELBW population.

FINDINGS/RESULTS

No study found was exclusive to the ELBW population. All studies ranged from ELBW to full-term neonates. Studies supported the use of BCPAP in the ELBW, demonstrating decreased incidence of chronic lung disease and barotrauma through the use of oscillation and permissive hypercapnia.

IMPLICATIONS FOR PRACTICE

Literature supports the use of nasal bubble CPAP in the ELBW population. Barriers such as septal erosion, pneumothorax, inconsistent pressures, and air in the abdomen were identified and management recommendations were provided.

IMPLICATIONS FOR RESEARCH

Studies are needed comparing outcomes of nasal bubble CPAP use with other forms of CPAP in the ELBW infant, comparison of prongs to mask for nasal bubble CPAP, and comparing interventions to recommend optimal care bundles to prevent nasal septum injuries.