Noninvasive Ventilation in Acute Asthma Exacerbations: A Systematic Review.

Area of Science:

• Pulmonology
• Critical Care Medicine
• Respiratory Medicine

Background:

• Clinical practice guidelines lack robust recommendations on noninvasive ventilation (NIV) for acute asthma exacerbations due to limited evidence.
• Existing evidence syntheses are outdated, necessitating an update with recent randomized controlled trials (RCTs) and observational studies.

Purpose of the Study:

• To update evidence syntheses for noninvasive ventilation (NIV) in acute asthma exacerbations.
• To clarify the effects of NIV compared to standard medical therapy alone.

Main Methods:

• Systematic literature search of Medline, Embase, and Cochrane Library.
• Meta-analysis of 8 RCTs and 5 observational studies comparing NIV plus standard therapy versus standard therapy alone.
• Evidence appraised using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach.

Main Results:

• Noninvasive ventilation (NIV) was associated with reduced intubation rates (RCTs: RR=0.46; observational: RR=0.55) and admission rates (RR=0.57).
• NIV significantly decreased time to improvement in accessory muscle use (MD=-1.13 h).
• Other outcomes like dyspnea and spirometry measures favored NIV but lacked statistical significance; evidence quality was low to very low.

Conclusions:

• Statistically significant outcomes favored NIV plus standard medical therapy for acute asthma exacerbations.
• NIV may reduce intubation rates, a potentially clinically important effect given its association with mortality.
• A trial of NIV in addition to standard medical therapy may benefit patients with acute asthma exacerbations.