呼吸衰竭患者中T型管呼吸和壓力支持通氣作為自主呼吸測 試的比較:系統性回顧和統合分析與試驗計劃書

Abstract

背景 機械通氣(Mechanical ventilation)是支持呼吸衰竭病人的重要維生工具，待造 成呼吸衰竭的原因被治癒後，病人會被評估是否合適脫離機械通氣。自主呼吸 測試(Spontaneous Breathing Trial, SBT)用於評估呼吸器使用的病人是否適合脫 離呼吸器。目前，低程度的壓力支持型通氣(Pressure Support Ventilation, PSV) 和 T 型管呼吸這兩種 SBT 方法何者為較佳的自主呼吸測試仍存在爭議。過去的 研究結果並不一致，有些可能影響研究結果的因素如病人族群、SBT 持續時間 吐氣末正壓(Positive End Expiratory Pressure, PEEP)設定、以及成功拔管的定 義等，尚未被評估。因此，我們進行了系統性回顧與統合分析，比較了 PSV 和 T 型管呼吸，並考慮了上述因素以期減少統合分析的異質性並探索潛在的影響因 子。 方法 我們使用 SBT 和呼吸器使用作為關鍵詞，搭配 MeSH 詞彙、截斷詞、布林邏輯 和手動檢索，搜索在 2023 年 3 月之前發表在 PubMed、MEDLINE 和 Cochrane CENTRAL 數據庫中的隨機對照試驗。共找出 131 篇文章，經篩選和評讀後，選 擇了 9 個符合條件的研究進行進一步分析。 結果 9 個納入研究共包括了 4485 位受試者，PSV 呈現出比 T 型管呼吸更好的拔管成 功率，但此結果有相當的異質性。分層分析的結果顯示，PSV 的壓力輔助設定 在≦7 cmH2O 時， PSV 才有比 T 型管呼吸有更好的拔管成功率。PEEP 設定值 的高低不影響比較結果。另在不同的拔管成功定義之下(72 小時以下或超過 72 小時不發生再插管)，兩種 SBT 方法之優劣會有不同的結果。 討論 成功的呼吸器脫離對病人而言至關重要。自主呼吸測試，包括 PSV 和 T 型管呼 吸，可以加快呼吸器脫離。我們的統合分析結果得到 PSV 作為 SBT 可能優於 T 型管呼吸的結論。然而，需要進一步研究來釐清這樣的結果是否受不同成功脫 離的定義所影響，以及是否適用於所有病人族群。 結論 PSV 呈現出比 T 型管呼吸更好的拔管成功率，但此結果有相當的異質性。次族 群分析顯示，在 PSV 壓力設置為≦7 cmH2O 的 SBT 中，PSV 的拔管成功率優於 T 型管呼吸。由於期間較短的拔管成功定義可能會高估 PSV 的優勢。我們的目標是評估 SBT 中的 PSV≦7 cmH2O 和 T 型管呼吸在拔管結果方面是否存在差 異，且將呼吸器成功脫離定義為連續 7 天以上不再需要呼吸器。

Backgroud Mechanical ventilation is an important life support modality for patients with respiratory failure. After the cause of respiratory failure is resolved, ventilated patients would be evaluated to determine whether they are ready for liberation from mechanical ventilation. Spontaneous breathing trials (SBTs) are used to assess the readiness of mechanically ventilated patients for liberation from mechanical ventilation. There is a debate regarding the superiority of the two most commonly used SBT methods, namely low-level pressure support ventilation (PSV) and T-piece. Previous studies show inconsistent results in comparing these two SBT methods, which might be contributed by different patient populations, SBT duration, positive end-expiratory pressure (PEEP) settings and definition of successful extubation. Therefore, we conducted an updated systematic review and meta-analysis to compare T-piece and PSV, and explore the source of heterogeneity and potential effect modifications with the aforementioned factors. Methods We used keyword searching with the MeSH terms of spontaneous breathing trial, and mechanical ventilation, combining with truncated words, Bollinger logic and manual to search randomized controlled trials published in the PubMed, MEDLINE and Cochrane CENTRAL databases before March 2023. A total of 131 articles were identified. After reviewing the abstract and full articles, nine eligible studies were included for further analysis. Results The nine included studies involving 4485 patients. Compared with T-piece, an SBT with PSV led to significantly higher rates of successful extubation, but this pooled result was associated with moderate heterogeneity. In stratified analysis, the superiority of PSV to T-piece was only observed in the group of pressure support of 7 cmH2O and below but not in the group with pressure support more than 7 cmH2O. PEEP setting did not impose effect modification to the pooled results. When defining successful extubation with ≦72 hours of remaining ventilator free had effect modification on the comparison between PSV versus T-piece. Discussion Successful liberation from mechanical ventilation is crucial for patient outcomes. Spontaneous breathing trials, including PSV and T-piece, can facilitate faster discontinuation of ventilation. Our findings support the superiority of PSV over T-piece as SBTs, particularly with low-level PSV. The definition of weaning success may affect the efficacy of weaning in both PSV and T-piece groups. Longer definitions of successful weaning, as discussed in previous studies, showed no significant difference between the two methods. Further research is needed to explore the impact of stricter definitions and their applicability to different patient populations, such as COPD and obesity. These findings align with previous research emphasizing the importance of accurately defining weaning success based on specific patient populations. Conclusion SBT with PSV led to significantly higher rates of successful extubation, but this pooled result was associated with moderate heterogeneity. Subgroup analysis showed that PSV was superior to T-piece as an SBT when inspiratory pressure was set at ≦7 cmH2O. Additionally, our analysis highlighted that the definition of weaning success significantly affects the superiority comparison between these two SBT methods.