Umbrello Michele, Brogi Etrusca, Formenti Paolo, Corradi Francesco, Forfori Francesco
Department Intensive Care and Anesthesia, ASST Ovest Milanese, Ospedale Nuovo di Legnano, 20025 Legnano, Italy.
Department Anaesthesia and Intensive Care, University of Pisa, 56126 Pisa, Italy.
J Clin Med. 2023 Dec 20;13(1):26. doi: 10.3390/jcm13010026.
Muscle wasting begins as soon as in the first week of one's ICU stay and patients with multi-organ failure lose more muscle mass and suffer worse functional impairment as a consequence. Muscle wasting and weakness are mainly characterized by a generalized, bilateral lower limb weakness. However, the impairment of the respiratory and/or oropharyngeal muscles can also be observed with important consequences for one's ability to swallow and cough. Muscle wasting represents the result of the disequilibrium between breakdown and synthesis, with increased protein degradation relative to protein synthesis. It is worth noting that the resulting functional disability can last up to 5 years after discharge, and it has been estimated that up to 50% of patients are not able to return to work during the first year after ICU discharge. In recent years, ultrasound has played an increasing role in the evaluation of muscle. Indeed, ultrasound allows an objective evaluation of the cross-sectional area, the thickness of the muscle, and the echogenicity of the muscle. Furthermore, ultrasound can also estimate the thickening fraction of muscle. The objective of this review is to analyze the current understanding of the pathophysiology of acute skeletal muscle wasting and to describe the ultrasonographic features of normal muscle and muscle weakness.
肌肉萎缩在入住重症监护病房（ICU）的第一周就可能开始，多器官功能衰竭的患者会损失更多肌肉量，并因此遭受更严重的功能损害。肌肉萎缩和无力主要表现为全身性、双侧下肢无力。然而，也可观察到呼吸和/或口咽肌肉的损害，这对患者的吞咽和咳嗽能力有重要影响。肌肉萎缩是分解代谢与合成代谢失衡的结果，蛋白质降解相对于蛋白质合成增加。值得注意的是，由此导致的功能残疾在出院后可持续长达5年，据估计，高达50%的患者在ICU出院后的第一年无法重返工作岗位。近年来，超声在肌肉评估中发挥着越来越重要的作用。事实上，超声可以对肌肉的横截面积、厚度和回声性进行客观评估。此外，超声还可以估计肌肉的增厚分数。本综述的目的是分析目前对急性骨骼肌萎缩病理生理学的认识，并描述正常肌肉和肌肉无力的超声特征。
