[Application of a spontaneous breathing trial based on high-flow oxygen therapy in weaning of mechanically ventilated patients].

Abstract

To evaluate the application efficacy of a spontaneous breathing trial (SBT) based on high-flow oxygen therapy (HFOT) during the weaning process in mechanically ventilated patients. A randomized controlled trial was conducted. A total of 163 patients undergoing invasive mechanical ventilation admitted to the Department of Critical Care Medicine, Zhongda Hospital, Southeast University, from September 2024 to July 2025 were enrolled and randomly assigned to the HFOT group (80 cases) or the pressure support ventilation (PSV) group (83 cases). The HFOT group received SBT based on HFOT, while the PSV group received SBT based on PSV. Baseline data were collected and compared between the two groups, and adverse events during SBT were recorded. The primary outcome was the success rate of extubation within 48 hours. Secondary outcomes included vital signs, sputum grade, arterial blood gas parameters measured before SBT and 30 minutes after SBT initiation, SBT success rate, and prognostic outcomes [duration of mechanical ventilation, length of intensive care unit (ICU) stay, hospitalization costs, ICU mortality, in-hospital mortality, and 28-day mortality]. A total of 163 mechanically ventilated patients were included, with 80 in the HFOT group and 83 in the PSV group. There were no statistically significant differences in baseline data or prognostic outcomes between the two groups. The SBT success rates were 100% (80/80) in the HFOT group and 98.8% (82/83) in the PSV group, and the 48-hour extubation success rates were 87.5% (70/80) and 80.5% (66/82), respectively, with no statistically significant differences (both P>0.05). At 30 minutes after SBT initiation, the heart rate (HR_0.5) and the decrease in HR (ΔHR_0.5) in the HFOT group were significantly lower than those in the PSV group [HR_0.5: 87.10±12.73 vs. 94.28±13.60; ΔHR_0.5: 0.0 (-3.0, 2.0) vs. -1.0 (-5.0, 1.0); both P<0.05]. No significant differences were observed in other vital signs, sputum grade, or arterial blood gas parameters between the two groups. No safety events occurred in either group during the trial, indicating good safety. Subgroup analysis showed statistically significant interactions between intervention modality and both age and duration of mechanical ventilation (both P<0.05). In patients aged≥65 years, the ICU length of stay in the HFOT group was significantly shorter by a mean of 83.12 hours [95% confidence interval (95%CI) was -151.28 to -14.96] compared with the PSV group. In patients with mechanical ventilation duration≥24 hours, the ICU length of stay in the HFOT group was significantly shorter by a mean of 157.40 hours (95%CI was -254.60 to -60.20) compared with the PSV group. SBT based on HFOT is safe for weaning mechanically ventilated patients and offers certain physiological advantages in improving HR. In elderly patients (≥65 years) and those with prolonged mechanical ventilation (≥24 hours), HFOT-based SBT can significantly shorten ICU length of stay, but it does not show a clear advantage in improving the 48-hour extubation success rate.