Davies Michael L, Chapple Lee-Anne S, Chapman Marianne J, Moran John L, Peake Sandra L
Critical Care Services, Royal Adelaide Hospital, Adelaide, SA, Australia.
Discipline of Acute Care Medicine, University of Adelaide, Adelaide, SA, Australia.
Crit Care Resusc. 2017 Jun;19(2):117-127.
Protein is a fundamental component of critical care nutrition, but there has been uncertainty about the optimal amount. We undertook this systematic review and meta-analysis to examine the relationship between delivered protein and mortality in randomised controlled trials (RCTs) of nutritional interventions involving critically ill adults. Secondary outcomes included the effect of protein dose on lengths of stay, mechanical ventilation and incidence of infections.
We reviewed the relevant English-language literature published between 1966 and 2015 and identified RCTs comparing different strategies of nutritional support lasting at least 48 hours in critically ill adults. Articles were included if mortality was reported and the difference in delivered protein between interventions was significant (P < 0.05). We calculated summary estimates for mortality as odds ratios (ORs) with 95% confidence intervals (CIs) using a random-effects estimator, and we used meta-regression to assess the effect of delivered protein on mortality.
From 3016 assessed records, 357 full-text articles were reviewed and 14 studies, investigating various interventions and routes of nutrition and comprising 3238 patients, were included. The mean protein delivered was 42.95 g/day (SD, 20.45 g/day) or 0.67 g//kg/day (SD, 0.38 g/kg/day) in patients receiving less protein, and 67.15 g/day (SD, 28.47 g/day) or 1.02 g/kg/day (SD, 0.42 g/kg/day) in the higher protein group. Provision of less protein did not influence mortality risk (pooled OR, 0.935; 95% CI, 0.716 -1.219; P = 0.618; I = 48.2%). Meta-regression analysis did not show a relationship between mean daily protein delivered and mortality (P = 0.433; I = 50.18%). There were no differences between groups in any secondary outcomes.
Delivery of varying amounts of nutritional protein was not associated with any effect on mortality.
蛋白质是重症监护营养的基本组成部分，但最佳摄入量一直存在不确定性。我们进行了这项系统评价和荟萃分析，以研究在涉及成年重症患者的营养干预随机对照试验（RCT）中，蛋白质供给量与死亡率之间的关系。次要结局包括蛋白质剂量对住院时间、机械通气和感染发生率的影响。
我们检索了1966年至2015年间发表的相关英文文献，确定了比较成年重症患者至少持续48小时不同营养支持策略的RCT。如果报告了死亡率且干预措施之间蛋白质供给量的差异显著（P<0.05），则纳入相关文章。我们使用随机效应估计器计算死亡率的汇总估计值，以比值比（OR）及其95%置信区间（CI）表示，并使用荟萃回归分析评估蛋白质供给量对死亡率的影响。
在3016条评估记录中，共审查了357篇全文文章，纳入了14项研究，这些研究调查了各种干预措施和营养途径，共纳入3238例患者。蛋白质摄入量较低的患者平均每日蛋白质摄入量为42.95克/天（标准差，20.45克/天）或0.67克/千克/天（标准差，0.38克/千克/天），蛋白质摄入量较高的组为67.15克/天（标准差，28.47克/天）或1.02克/千克/天（标准差，0.42克/千克/天）。提供较少的蛋白质并不影响死亡风险（合并OR，0.935；95%CI，0.716-1.219；P=0.618；I²=48.2%）。荟萃回归分析未显示每日平均蛋白质供给量与死亡率之间存在关联（P=0.433；I²=50.18%）。两组在任何次要结局方面均无差异。
不同量的营养蛋白质供给与死亡率的任何影响均无关联。
