間接熱量測量於重症病人之臨床應用與挑戰

The Clinical Application and Challenge of Indirect Calorimetry in Critically Ill Patients

重症病人的熱量目標是病人康復重要的一環，間接熱量測量比預測方程式更能準確提供熱量目標。本文透過系統性文獻整理，介紹間接熱量測量的原理、適應症、操作注意事項、實證研究結果探討及在臨床上的應用與挑戰。間接熱量測量原理是分析重症病人耗氧量和二氧化碳產生量的代謝測量值，並使用Weir方程式，轉換為預測熱量消耗。間接熱量測量適用於重症病人，但有其限制，於置放胸管、呼吸器參數設定高如氧氣濃度>60%、吐氣末正壓>10cmH2O、病情不穩定躁動或是接受特殊治療的病人不適用。本文列出操作測量前、中、後之注意事項。實證研究證實，利用間接熱量測量相較預測方程式估算更能精準測得熱量消耗，並且能降低重症病人短期死亡率，但對於住院天數、呼吸器使用時間和感染率尚未達到一致性結論，仍須進一步探討，此外保險給付、設備費用短缺、人力缺乏和人員知識技能認知不足等是臨床應用的挑戰，值得進一步去探討。

Energy target is crucial for the recovery of critically ill patients. Indirect calorimetry (IC) is recommended by the Nutrition Society as it measures energy expenditure (EE) more accurately than predictive equations (PE), providing a reliable method for determining energy target. This article reviews the principles, indications, procedures, current evidence, clinical applications and challenges of indirect calorimetry in critically ill patients. The principle of indirect calorimetry involves analyzing metabolic measurements of oxygen consumption and carbon dioxide production to calculate energy expenditure using the Weir equation. While indirect calorimetry is suitable for use in critically ill patients, it has certain limitations, such as the need for chest tube placement, higher ventilator parameter settings for example fraction of inspired oxygen > 60% and positive end expiratory pressure > 10cmH2O, the presence of patient agitation or instability and patients on organ support treatments. Precautions must be taken before, during, and after indirect calorimetry measurements. Studies have demonstrated that indirect calorimetry is superior to predictive equations in determining energy target and can reduce short-term mortality. However, there is no consensus on its impact on intensive care unit length of stay, duration of mechanical ventilation, and infection rates, highlighting the need for further research. In addition, shortages of insurance benefits, equipment costs, lack of staff, and insufficient awareness of related knowledge and skills are challenges to clinical application and are worthy of further exploration.