Background: Expiratory flow limitation (EFL) is an inability to exceed a certain flow regardless of the pressure exerted, which appears in 60% of patients with extubation failure. However, an appropriate weaning method for the patients with EFL remains unknown.
Objectives: We aimed to evaluate an effect of different techniques of spontaneous breathing trials (SBT) on a success rate of extubation in the patients with EFL.
Methods: We conducted a non-inferiority randomized controlled trial comparing between 30-minute pressure support ventilation (PSV) and 30-minute T-piece in ventilated patients with EFL who got ready to wean. The primary outcome was successful extubation during a 72-hour post-extubation period. Secondary outcomes were a reintubation rate within 7 days, time to reintubation, and a SBT success rate.
Results: A total of 99 ventilated patients with EFL consisting of male (50.5%) with the median age of 70  years were recruited. The most common cause of acute respiratory failure was intrapulmonary cause (68.7%). The eligible patients were randomized into 2 groups with a ratio of 1:1. The success rate of extubation during the 72-hour period in the PSV group was non-inferior to the T-piece group: 82% and 81.63%, respectively (95%CI -0.148 to 0.156, p=0.0475). There was also non-inferiority in the reintubation rate within 7 days (22.9% in the PSV group VS 15.2% in the T-piece group; 95%CI -0.081 to 0.235, p=0.005) and the SBT success rate (96% in the PSV group VS 93.9% in the T-piece group; 95%CI -0.065 to 0.108, p<0.001). There was no significant difference in the median time to reintubation between these 2 groups (55 [95.5] hours in PSV VS 25.33  hours in the T-piece group, p=0.683).
Conclusions: Among patients with EFL, the 30-minute SBT with PSV was non-inferior to the T-piece SBT in terms of the successful extubation during the 72-hour period, successful SBT, and reintubation rate within 7 days. This was the first study demonstrating that the different techniques of SBT did not affect the weaning outcomes in the patients with EFL.