Preventing extubation failure in preterm infants: nasal CPAP remains the standard of care

Abstract

Commentary on: Manley BJ, Owen LS, Doyle LW, Andersen CC, Cartwright DW, Pritchard MA, Donath SM, Davis PG. High-Flow Nasal Cannulae in Very Preterm Infants after Extubation. N Engl J Med 2013; 369:1425-33. PMID 24106935. Improving rates of extubation failure in very preterm infants remains an important and elusive goal. Postextubation CPAP prevents extubation failure and is the standard of care for preterm infants 1, 2. Alternative methods of delivering positive distending pressure to preterm infants, including high-flow nasal cannula (HFNC), are widely used and increasingly popular. The stated advantages of HFNC are ease of use, increased comfort and less nasal trauma. Unfortunately, retrospective analysis suggests potential harm from HFNC use in VLBW infants, highlighting the urgent need for prospective randomised controlled trials to guide clinical practice 3. Manley and colleagues determined whether HFNC performed similarly to nasal CPAP for preventing extubation failure in very preterm infants (<32 weeks) 4. The trial revealed that HFNC was noninferior to CPAP in preventing extubation failure. Importantly, noninferiority was defined as 20 percentage points above the extubation failure rate for CPAP. Treatment failure occurred in 34.2% of the HFNC group and 25.8% in the CPAP group (risk difference, 8.4 percentage points, 95% confidence interval, −1.9 to 18.7). While this difference did not reach statistical significance, the upper limit of the 95% confidence interval bordered on the margin of noninferiority. A potential criticism of this otherwise well done trial has been using up to a 20% difference to define ‘noninferior’ 5. Additionally, the difference in failure rate was exaggerated in infants <26 weeks gestational age. Specifically, 61.3% of infants <26 weeks failed CPAP, while 81.3% of infants failed HFNC. Although the study was not powered to detect differences in this small subgroup of patients (63 infants), the authors urge caution when considering the use of HFNC in these patients. Furthermore, approximately half of the patients failing HFNC were salvaged with CPAP, thus resulting in a lower (17.8%) re-intubation rate in patients randomised to HFNC compared to those randomised to CPAP (25.2%). Lastly, nasal trauma was infrequent and rates did not differ by group. Where do these data leave us? Does HFNC perform similarly to CPAP for preventing extubation failure in very preterm infants (<32 weeks GA)? Statistically, yes. However, the authors acknowledge that they ‘chose a generous noninferiority margin’ 6. Ultimately, does HFNC perform well enough compared to CPAP to justify its use to prevent extubation failure? As the authors pointed out, these data clearly argue against the routine use of HFNC following extubation for infants <26 weeks. Furthermore, these data provide no compelling argument that HFNC should be considered as equivalent to nasal CPAP as the current standard of care for preventing extubation failure. However, these data would suggest that HFNC is safe and well tolerated and warrants further study in the NICU. https://ebneo.org/2015/04/delivering-non-invasive-positive-pressure-to-prevent-extubation-failure-in-preterm-infants-nasal-cpap-remains-the-standard-of-care/ None. CW: R01HL132941. LS: T32007186-32.