The use of noninvasive positive pressure ventilation for severe asthma: a systematic review and meta-analysis of randomized controlled trials with trial sequential analysis

Abstract

Introduction: To evaluate the effectiveness of noninvasive positive pressure ventilation (NPPV) versus standard therapy in severe asthma exacerbations through meta-analysis.

Methods: Nine randomized controlled trials (344 patients) were analyzed from inception to August 2024. Primary outcomes included respiratory rate, forced expiratory volume in first second (FEV1), and oxygen saturation (SpO2). Random effect models and trial sequential analyses were employed.

Results: NPPV demonstrated significant reduction in respiratory rate versus standard therapy (mean difference [MD] -3.97, 95% CI -7.32 to -0.61, p = 0.02), though with high heterogeneity (I² = 87%). FEV1 showed significant improvement with NPPV (MD 15.56%, 95% CI 6.86 to 24.26, p < 0.001) based on two studies. SpO2 showed no significant improvement (MD 0.62%, 95% CI -0.14 to 1.37, p = 0.11). No differences were found between pediatric and adult populations. Trial sequential analyses indicated insufficient evidence for definitive conclusions regarding respiratory rate and SpO2 improvements.

Conclusions: While NPPV may benefit severe asthma patients, particularly in reducing respiratory rate and improving FEV1, current evidence is insufficient for recommending routine clinical use. Larger randomized controlled trials are needed to establish NPPV's effectiveness in severe asthma exacerbation treatment.

Protocol registration: registration ID CRD42024580051.

Keywords: Asthma; FEV 1; NIV; NPPV; SpO2; noninvasive ventilation; respiratory rate; status asmaticus.