中文摘要：

目的观察行机械通气的重度脓毒症患者累积能量平衡状况及对预后的影响。方法前瞻性、观察性研究测定60例严重脓毒症行机械通气患者的静息能量消耗（MREE），以此为目标营养值给予能量热卡；观察记录每日能量摄入、开始喂养时间、并发症及预后，计算每周能量累积平衡，分析影响预后的临床因素。结果患者能量不足第1周占66．7％，能量负平衡在4周内均存在，其中前2周与目标能量值有较大差异（t=4．661，P=0．000；t=2．79，P=0．007）。相关性分析表明，能量负平衡与感染、在ICU停留时间相关（P〈0．05），而与机械通气时间及28d死亡率无明显相关（P〉0．05）。结论早期肠内营养，避免能量摄入不足，是改善预后的有效手段。

英文摘要：

Objective To investigate the state of energy balance in severe sepsis patients, and to analyze the cumulative energy balance on the patient＇s outcome. Methods This prospective observational study was conducted in 60 severe sepsis patients with mechanical ventilation, indirect calorimetry （IC） was used to obtain measured resting energy expenditure （MREE）, energy delivery, time to feeding, complications and outcome were recorded. The balance of cumulative energy of every week and energy deficit was calculated. Liner regression was used to analyze the correlation of energy balance and outcomes. Results Energy deficit mainly occurred in the first week and accounted for 66. 7%. Negative energy balance would remained four weeks and the difference between energy target and energy delivery during the first two weeks were significantly larger（ t = 4. 661, P = 0. 000 ; t = 2.79, P = 0.007）. Liner regression showed the correlations between the negative energy balance and infections and length of ICU stay, there was no correlation between the length of ventilation and mortality. Conclusion It might be an effective strategy to improve outcomes by supplying early enteral nutrition to avoid energy deficits.