Background: A spontaneous breathing trial (SBT) is recommended to help patients to liberate themselves from mechanical ventilation as soon as possible in the ICU. The respiratory workload in SBT, which depends on being with or without respiratory support and a specific time, is more accurate to reflect how much support the weaning patients need compared with only considering SBT technologies.
Aim: To compare and rank the effectiveness of different respiratory workloads during SBT via differing technologies (Pressure Support Ventilation and T-piece) and differing duration (30 and 120 min) in SBTs.
Study design: A comprehensive literature search was performed in six English electronic databases to identify eligible randomized controlled trials (RCTs) published before September 2020. The pooled risk ratio (RR) with 95% confidence interval (CI) was calculated by Markov chain Monte Carlo methods. A Bayesian network meta-analysis was conducted using "gemtc" version 0.8.2 of R software. Each intervention's ranking possibilities were calculated using the surface under the cumulative ranking analysis (SUCRA).
Results: A total of nine RCTs including 3115 participants were eligible for this network meta-analysis involving four different commonly used SBT strategies and four outcomes. The only statistically significant difference was between Pressure Support Ventilation (PSV) 30 min and T-piece 120 min in the outcome of the rate of success in SBTs (RR = 0.91; 95% CI, 0.84-0.98). The cumulative rank probability showed that the rate of success in SBT from best to worst was PSV 30 min, PSV 120 min, T-piece 30 min and T-piece 120 min. PSV 30 min and PSV 120 min are more likely to have a higher rate of extubation (SUCRA values of 82.5% for 30 min PSV, 70.7% for 120 min PSV, 36.4% for T-piece 30 min, 10.4% for T-piece 120). Meanwhile, T-piece 120 min (SUCRA, 62.9%) and PSV 120 min (SUCRA, 60.9%) may result in lower reintubation rates, followed by T-piece 30 min (SUCRA, 41.8%) and PSV 30 min (SUCRA, 34.4%).
Conclusions and relevance to clinical practice: In comprehensive consideration of four outcomes, regarding SBT strategies, 30-min PSV was superior in simple-to-wean patients. Besides, 120-min T-piece and 120-min PSV are more likely to achieve a lower reintubation rate. Thus, the impact of duration is more significant among patients who have a high risk of reintubation. It is still unclear whether the SBTs affect the outcome of mortality; further studies may need to explore the underlying mechanism.
Keywords: T-piece; network meta-analysis; pressure support ventilation; spontaneous breathing trials; systematic review.
© 2022 British Association of Critical Care Nurses.