COVID-19 ARDS shares features with non-COVID ARDS but also demonstrates distinct physiological differences. Despite a lack of strong evidence, prone positioning has been advocated as a key therapy for COVID-19 ARDS. The effects of prone position in critically ill patients with COVID-19 are not fully understood, nor is the optimal time of initiation defined. In this nationwide cohort study, we aimed to investigate the association between early initiation of prone position and mortality in mechanically ventilated COVID-19 patients with low oxygenation on ICU admission. Using the Swedish Intensive Care Registry (SIR), all Swedish ICU patients ≥ 18 years of age with COVID-19 admitted between March 2020, and April 2021 were identified. A study-population of patients with PaO2/FiO2 ratio ≤ 20 kPa on ICU admission and receiving invasive mechanical ventilation within 24 h from ICU admission was generated. In this study-population, the association between early use of prone position (within 24 h from intubation) and 30-day mortality was estimated using univariate and multivariable logistic regression models. The total study cohort included 6350 ICU patients with COVID-19, of whom 46.4% were treated with prone position ventilation. Overall, 30-day mortality was 24.3%. In the study-population of 1714 patients with lower admission oxygenation (PaO2/FiO2 ratio ≤ 20 kPa), the utilization of early prone increased from 8.5% in March 2020 to 48.1% in April 2021. The crude 30-day mortality was 27.2% compared to 30.2% in patients not receiving early prone positioning. We found no significant association between early use of prone positioning and survival. During the first three waves of the COVID-19 pandemic, almost half of the patients in Sweden were treated with prone position ventilation. We found no association between early use of prone positioning and survival in patients on mechanical ventilation with severe hypoxemia on ICU admission. To fully elucidate the effect and timing of prone position ventilation in critically ill patients with COVID-19 further studies are desirable.

中文翻译：

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早期俯卧位对 COVID-19 机械通气患者 30 天死亡率的患病率和影响：一项全国性队列研究

COVID-19 ARDS 与非 COVID ARDS 具有相同的特征，但也表现出明显的生理差异。尽管缺乏强有力的证据，但仍提倡俯卧位作为 COVID-19 ARDS 的关键疗法。俯卧位对 COVID-19 危重患者的影响尚不完全清楚，也未确定最佳起始时间。在这项全国性队列研究中，我们旨在调查早期开始俯卧位与 ICU 入院时氧合低的机械通气 COVID-19 患者死亡率之间的关系。使用瑞典重症监护登记处 (SIR)，确定了 2020 年 3 月至 2021 年 4 月期间收治的所有 18 岁以上的瑞典 ICU 患者 COVID-19。生成了一个研究人群，即在 ICU 入院时 PaO2/FiO2 比 ≤ 20 kPa 并在 ICU 入院后 24 小时内接受有创机械通气的患者。在本研究人群中，使用单变量和多变量逻辑回归模型估计了早期使用俯卧位（插管后 24 小时内）与 30 天死亡率之间的关联。整个研究队列包括 6350 名 COVID-19 ICU 患者，其中 46.4% 接受了俯卧位通气治疗。总体而言，30 天死亡率为 24.3%。在 1714 名入院氧合较低的患者（PaO2/FiO2 比率 ≤ 20 kPa）的研究人群中，早期俯卧的利用率从 2020 年 3 月的 8.5% 增加到 2021 年 4 月的 48.1%。粗 30 天死亡率为 27.2%相比之下，未接受早期俯卧位的患者为 30.2%。我们发现早期使用俯卧位与生存之间没有显着关联。在 COVID-19 大流行的前三波期间，瑞典近一半的患者接受了俯卧位通气治疗。我们发现早期使用俯卧位与机械通气患者入ICU时严重低氧血症的生存率之间没有关联。为了充分阐明俯卧位通气对 COVID-19 重症患者的效果和时机，需要进一步研究。我们发现早期使用俯卧位与机械通气患者入ICU时严重低氧血症的生存率之间没有关联。为了充分阐明俯卧位通气对 COVID-19 重症患者的效果和时机，需要进一步研究。我们发现早期使用俯卧位与机械通气患者入ICU时严重低氧血症的生存率之间没有关联。为了充分阐明俯卧位通气对 COVID-19 重症患者的效果和时机，需要进一步研究。