Critical Care Medicine, Department of Medicine, Christiana Care Healthcare System, Christiana Care Value Institute, Newark, Delaware, USA, Sidney Kimmel Medical College, Philadelphia, Pennsylvania, USA.
Department of Behavioral Health and Nutrition, University of Delaware, Newark, Delaware, USA.
Nutrition. 2019 Oct;66:48-53. doi: 10.1016/j.nut.2019.02.021. Epub 2019 Apr 26.
The aims of this study were, first, to compare the predicted (calculated) energy requirements based on standard equations with target energy requirement based on indirect calorimetry (IC) in critically ill, obese mechanically ventilated patients; and second, to compare actual energy intake to target energy requirements.
We conducted a prospective cohort study of mechanically ventilated critically ill patients with body mass index ≥30.0 kg/m for whom enteral feeding was planned. Clinical and demographic data were prospectively collected. Resting energy expenditure was measured by open-circuit IC. American Society of Parenteral and Enteral Nutrition (APSPEN)/Society of Critical Care Medicine (SCCM) 2016 equations were used to determine predicted (calculated) energy requirements. Target energy requirements were set at 65% to 70% of measured resting energy expenditure as recommended by ASPEN/SCCM. Nitrogen balance was determined via simultaneous measurement of 24-h urinary nitrogen concentration and protein intake.
Twenty-five patients (mean age: 64.5 ± 11.8 y, mean body mass index: 35.2 ± 3.6 kg/m) underwent IC. The mean predicted energy requirement was 1227 kcal/d compared with mean measured target energy requirement of 1691 kcal/d. Predicted (calculated) energy requirements derived from ASPEN/SCCM equations were less than the target energy requirements in most cases. Actual energy intake from enteral nutrition met 57% of target energy requirements. Protein intake met 25% of target protein requirement and the mean nitrogen balance was -2.3 ± 5.1 g/d.
Predictive equations underestimated target energy needs in this population. Further, we found that feeding to goal was often delayed resulting in failure to meet both protein and energy intake goals.
本研究的目的首先是比较基于标准方程的预测（计算）能量需求与基于间接热量测定法（IC）的目标能量需求在重症肥胖机械通气患者中的差异；其次，比较实际能量摄入与目标能量需求的差异。
我们对计划进行肠内喂养的机械通气重症肥胖患者进行了前瞻性队列研究，这些患者的体重指数（BMI）≥30.0kg/m²。前瞻性收集临床和人口统计学数据。通过开路 IC 测量静息能量消耗。使用美国肠外与肠内营养学会（ASPEN）/重症监护医学学会（SCCM）2016 方程来确定预测（计算）能量需求。目标能量需求设定为测量静息能量消耗的 65%至 70%，这是 ASPEN/SCCM 推荐的。通过同时测量 24 小时尿氮浓度和蛋白质摄入量来确定氮平衡。
25 名患者（平均年龄：64.5±11.8 岁，平均 BMI：35.2±3.6kg/m²）接受了 IC 检查。预测的能量需求平均值为 1227kcal/d，而目标能量需求的平均值为 1691kcal/d。大多数情况下，基于 ASPEN/SCCM 方程的预测能量需求低于目标能量需求。肠内营养的实际能量摄入仅满足目标能量需求的 57%。蛋白质摄入仅满足目标蛋白质需求的 25%，平均氮平衡为-2.3±5.1g/d。
在该人群中，预测方程低估了目标能量需求。此外，我们发现常常延迟达到目标喂养量，导致无法满足蛋白质和能量摄入目标。
