Taccone Paolo, Pesenti Antonio, Latini Roberto, Polli Federico, Vagginelli Federica, Mietto Cristina, Caspani Luisa, Raimondi Ferdinando, Bordone Giovanni, Iapichino Gaetano, Mancebo Jordi, Guérin Claude, Ayzac Louis, Blanch Lluis, Fumagalli Roberto, Tognoni Gianni, Gattinoni Luciano
Dipartimento di Anestesia e Rianimazione, Fondazione IRCCS-Ospedale Maggiore Policlinico, Mangiagalli, Regina Elena di Milano, 20122 Milan, Italy.
JAMA. 2009 Nov 11;302(18):1977-84. doi: 10.1001/jama.2009.1614.
Post hoc analysis of a previous trial has suggested that prone positioning may improve survival in patients with severe hypoxemia and with acute respiratory distress syndrome (ARDS).
To assess possible outcome benefits of prone positioning in patients with moderate and severe hypoxemia who are affected by ARDS.
DESIGN, SETTING, AND PATIENTS: The Prone-Supine II Study, a multicenter, unblinded, randomized controlled trial conducted in 23 centers in Italy and 2 in Spain. Patients were 342 adults with ARDS receiving mechanical ventilation, enrolled from February 2004 through June 2008 and prospectively stratified into subgroups with moderate (n = 192) and severe (n = 150) hypoxemia.
Patients were randomized to undergo supine (n = 174) or prone (20 hours per day; n = 168) positioning during ventilation.
The primary outcome was 28-day all-cause mortality. Secondary outcomes were 6-month mortality and mortality at intensive care unit discharge, organ dysfunctions, and the complication rate related to prone positioning.
Prone and supine patients from the entire study population had similar 28-day (31.0% vs 32.8%; relative risk [RR], 0.97; 95% confidence interval [CI], 0.84-1.13; P = .72) and 6-month (47.0% vs 52.3%; RR, 0.90; 95% CI, 0.73-1.11; P = .33) mortality rates, despite significantly higher complication rates in the prone group. Outcomes were also similar for patients with moderate hypoxemia in the prone and supine groups at 28 days (25.5% vs 22.5%; RR, 1.04; 95% CI, 0.89-1.22; P = .62) and at 6 months (42.6% vs 43.9%; RR, 0.98; 95% CI, 0.76-1.25; P = .85). The 28-day mortality of patients with severe hypoxemia was 37.8% in the prone and 46.1% in the supine group (RR, 0.87; 95% CI, 0.66-1.14; P = .31), while their 6-month mortality was 52.7% and 63.2%, respectively (RR, 0.78; 95% CI, 0.53-1.14; P = .19).
Data from this study indicate that prone positioning does not provide significant survival benefit in patients with ARDS or in subgroups of patients with moderate and severe hypoxemia.
clinicaltrials.gov Identifier: NCT00159939.
一项先前试验的事后分析表明，俯卧位可能改善重度低氧血症和急性呼吸窘迫综合征（ARDS）患者的生存率。
评估俯卧位对中重度低氧血症ARDS患者可能的预后益处。
设计、地点和患者：俯卧-仰卧位II研究，这是一项在意大利23个中心和西班牙2个中心进行的多中心、非盲、随机对照试验。患者为342例接受机械通气的ARDS成年患者，于2004年2月至2008年6月入组，并前瞻性地分为中度（n = 192）和重度（n = 150）低氧血症亚组。
患者在通气期间被随机分配接受仰卧位（n = 174）或俯卧位（每天20小时；n = 168）。
主要结局为28天全因死亡率。次要结局为6个月死亡率和重症监护病房出院时的死亡率、器官功能障碍以及与俯卧位相关的并发症发生率。
整个研究人群中，俯卧位和仰卧位患者的28天死亡率（31.0%对32.8%；相对风险[RR]，0.97；95%置信区间[CI]，0.84 - 1.13；P = 0.72）和6个月死亡率（47.0%对52.3%；RR，0.90；95% CI，0.73 - 1.11；P = 0.33）相似，尽管俯卧位组的并发症发生率显著更高。俯卧位和仰卧位组中度低氧血症患者在28天（25.5%对22.5%；RR，1.04；95% CI，0.89 - 1.22；P = 0.62）和6个月（42.6%对43.9%；RR，0.98；95% CI，0.76 - 1.25；P = 0.85）时的结局也相似。重度低氧血症患者的俯卧位组28天死亡率为37.8%，仰卧位组为46.1%（RR = 0.87；95% CI，0.66 - 1.14；P = 0.31），而其6个月死亡率分别为52.7%和63.2%（RR = 0.78；95% CI，0.53 - 1.14；P = 0.19）。
本研究数据表明，俯卧位对ARDS患者或中重度低氧血症患者亚组未提供显著的生存益处。
clinicaltrials.gov标识符：NCT00159939。
