Segaran E, Wandrag L, Stotz M, Terblanche M, Hickson M
Nutrition and Dietetics, Imperial College Healthcare NHS Trust, London, UK.
Adult Intensive Care Unit, Imperial College Healthcare NHS Trust, London, UK.
J Hum Nutr Diet. 2017 Apr;30(2):227-235. doi: 10.1111/jhn.12401. Epub 2016 Aug 1.
Critical illness is associated with muscle loss, weakness and poor recovery. The impact that illness and the ensuing metabolic response has on obese patients is not known. Objectives were to test if obese patients lose less muscle depth compared to non-obese patients; if a reduction in muscle depth was associated with reduced strength and recovery; and to assess the feasibility of these methods with a range of body mass index's (BMI).
A prospective observational pilot study of muscle depth in critically ill patients categorised by BMI was performed. Muscle depth changes were assessed by ultrasound on study days 1, 3, 5, 7, 12 and 14. Strength was measured via handgrip dynamometry and Medical Research Council (MRC) sum score on waking and at discharge from the intensive care unit. Level of dependency was measured with the Barthel index.
44 critically ill patients; 17 had normal BMI, 10 were overweight and 17 were obese. The three groups did not differ in baseline characteristics, except obese patients had significantly greater initial muscle depth. Muscle depth loss was similar between the BMI groups at each of the time points. Handgrip and MRC sum score were only possible in a small number of patients because of reduced alertness and weakness. Majority were deemed fully dependent based on the Barthel index.
Obese patients lost muscle depth in a comparable manner to non-obese patients, suggesting that BMI may not prevent muscle depth loss. It was not possible to determine the effect on strength because the clinical condition of patients precluded reliable measurements.
危重病与肌肉流失、虚弱及恢复不佳相关。疾病及其引发的代谢反应对肥胖患者的影响尚不清楚。研究目的是检验肥胖患者与非肥胖患者相比肌肉厚度减少是否更少；肌肉厚度减少是否与力量和恢复能力下降有关；并评估这些方法在一系列体重指数（BMI）范围内的可行性。
对按BMI分类的危重病患者进行了一项前瞻性观察性试点研究，以评估肌肉厚度变化。在研究的第1、3、5、7、12和14天通过超声评估肌肉厚度变化。通过握力测力计和在患者醒来时及从重症监护病房出院时的医学研究委员会（MRC）总分来测量力量。用巴氏指数测量依赖程度。
44例危重病患者；17例BMI正常，10例超重，17例肥胖。除肥胖患者初始肌肉厚度明显更大外，三组患者的基线特征无差异。在每个时间点，BMI组之间的肌肉厚度损失相似。由于警觉性降低和虚弱，只有少数患者能够进行握力和MRC总分测量。根据巴氏指数，大多数患者被认为完全依赖他人。
肥胖患者肌肉厚度减少的方式与非肥胖患者相似，这表明BMI可能无法预防肌肉厚度减少。由于患者的临床状况妨碍了可靠测量，因此无法确定对力量的影响。
