Comparing the effects and compliance between volume-assured and pressure support non-invasive ventilation in patients with chronic respiratory failure

Introduction: Standard bi-level non-invasive ventilation with fixed-level pressure support (PS) delivery may not maintain ventilation during the changes in pulmonary mechanics that occur throughout day and night, so average volume-assured pressure support (AVAPS) modes that target a preset volume by adjustment of PS may be effective.

Objective: Our meta-analysis wants to compare AVAPS and pressure support non-invasive ventilation (PS-NIV) regarding arterial blood gases (ABGs), sleep efficiency and compliance.

Method: Relevant publications indexed in PubMed, Cochrane Library, Embase, Web of Science, Wanfang Data, China National Knowledge Infrastructure and VIPI were identified. Appropriate articles identified from the reference lists of the above searches were also reviewed. We included randomized controlled trials involved the use of AVAPS and PS-NIV ventilation for chronic respiratory failure. Each included study weighted mean differences, and 95% confidence intervals (CI) were calculated for continuous outcomes. Statistical heterogeneity was assessed using the I² value ≤ 50% were considered as no statistical heterogeneity and used fixed effects model. Otherwise, a random effects model was used.

Results: Eight trials were eligible. No significant difference was observed between AVAPS and PS-NIV groups to compare PaCO₂ (OR -0.97, CI-2.54-0.61, P = 0.23) and PaO₂ (OR -1.81, CI-4.29-0.67, P = 0.15) in ABGs. There was no significant difference between the two groups with sleep efficiency (OR -3.31, CI-7.58-0.95, P = 0.13) and visual analog scale (OR 0.32, CI-6.97-7.61, P = 0.93).

Conclusions: The evidence shows there is no significant difference in clinical outcomes when comparing AVAPS and PS-NIV used for chronic respiratory failure patients.