Postextubation Respiratory Support: Is High-Flow Oxygen Therapy the Answer?

Commentary on High-Flow Nasal Cannula and Continuous Positive Airway Pressure Practices After the First-Line Support for Assistance in Breathing in Children Trials

Continuous positive airway pressure (CPAP) and heated humidified high-flow nasal cannula (HFNC) are commonly used to treat children admitted to the PICU who require more respiratory support than simple oxygen therapy. Much has been published on these two treatment modalities over the past decade, both in Pediatric Critical Care Medicine (PCCM ) and elsewhere. The majority of these studies are observational analyses of clinical, administrative, or quality improvement datasets and, therefore, are only able to establish associations between exposure to treatment and outcomes, not causation. None of the initial randomized clinical trials comparing HFNC and CPAP were definitive due to their relatively small sample sizes with insufficient power for meaningful clinical outcomes (e.g., escalation to bilevel noninvasive ventilation or intubation, duration of PICU-level respiratory support, mortality) and often yielded ambiguous findings or conflicting results. The recent publication of the First-Line Support for Assistance in Breathing in Children (FIRST-ABC) trials represented a major step toward understanding the role of CPAP and HFNC use in critically ill children. These large, pragmatic, randomized clinical trials examined the efficacy of CPAP and HFNC either for "step up" (i.e., escalation in respiratory support) during acute respiratory deterioration or for "step down" (i.e., postextubation need for respiratory support) management. This narrative review examines the body of evidence on HFNC published in PCCM , contextualizes the findings of randomized clinical trials of CPAP and HFNC up to and including the FIRST-ABC trials, provides guidance to PICU clinicians on how to implement the literature in current practice, and discusses remaining knowledge gaps and future research priorities.

Clinical Challenges in Pediatric Ventilation Liberation: A Meta-Narrative Review

OBJECTIVES

To map the evidence for ventilation liberation practices in pediatric respiratory failure using the Realist And MEta-narrative Evidence Syntheses: Evolving Standards publication standards.

DATA SOURCES

CINAHL, MEDLINE, COCHRANE, and EMBASE. Trial registers included the following: ClinicalTrials.gov, European Union clinical trials register, International Standardized Randomized Controlled Trial Number register.

STUDY SELECTION

Abstracts were screened followed by review of full text. Articles published in English language incorporating a heterogeneous population of both infants and older children were assessed.

DATA EXTRACTION

None.

DATA SYNTHESIS

Weaning can be considered as the process by which positive pressure is decreased and the patient becomes increasingly responsible for generating the energy necessary for effective gas exchange. With the growing use of noninvasive respiratory support, extubation can lie in the middle of the weaning process if some additional positive pressure is used after extubation, while for some extubation may constitute the end of weaning. Testing for extubation readiness is a key component of the weaning process as it allows the critical care practitioner to assess the capability and endurance of the patient's respiratory system to resume unassisted ventilation. Spontaneous breathing trials (SBTs) are often seen as extubation readiness testing (ERT), but the SBT is used to determine if the patient can maintain adequate spontaneous ventilation with minimal ventilatory support, whereas ERT implies the patient is ready for extubation.

CONCLUSIONS

Current literature suggests using a structured approach that includes a daily assessment of patient's readiness to extubate may reduce total ventilation time. Increasing evidence indicates that such daily assessments needs to include SBTs without added pressure support. Measures of elevated load as well as measures of impaired respiratory muscle capacity are independently associated with extubation failure in children, indicating that these should also be assessed as part of ERT.