title: Evaluation of the site specificity of acute disuse muscle atrophy developed during a relatively short period in critically ill patients according to the activities of daily living level: A prospective observational study.
abstract: BACKGROUND
  In critically ill patients, excessive bed rest and immobilisation have been shown to cause disuse muscle atrophy, which contributes to prolonged hospitalisation and decreased activity of daily living (ADL) levels. However, the degree and site specificity of acute disuse muscle atrophy in critically ill patients during a relatively short intensive care unit (ICU) stay have not been fully elucidated.
  
  
  METHODS
  Critically ill patients, who required bed rest on ICU admission, were eligible for this study. The degree of skeletal muscle atrophy was evaluated on the day of, and 72 and 144h after ICU admission by measuring the limb circumference in ADL-dependent or -independent patients separately at five different sites: the midpoint of the upper limb between the acromion and the olecranon, the maximum diameter of the triceps surae in the lower leg, and three different sites in the thigh at 5, 10, and 15cm above the superior pole of the patella. Value of the limb circumference was presented as a percentage relative to the baseline (median).
  
  
  RESULTS
  In ADL-dependent patients, limb circumferences at all five sites were decreased significantly at 144h compared with the baseline (98.9-100% in the upper limbs, 97.1-97.2% in the lower legs, and 96.5-99.1% in the thighs), but not at 72h. In contrast, the limb circumferences at almost all sites decreased significantly at both 72 and 144h (100% in the upper limbs, 94.5-94.7% in the lower legs, and 89.7-94.7% in the thighs), compared with the baseline in ADL-independent patients. Muscle atrophy was greater at the four different lower-limb sites compared to the upper limb during 144h in the ICU in the ADL-independent, but not in the ADL-dependent patients.
  
  
  CONCLUSIONS
  Compared to ADL-dependent patients, ADL-independent patients are prone to develop muscle weakness, especially in the lower limbs.
authors: Department of Nursing, Keio University Hospital, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Electronic address: modkenjis@z5.keio.jp.
authors: Kenji
authors: K
authors: Kawahara
authors: Department of Anesthesiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Electronic address: takeshi-su@a7.keio.jp.
authors: Takeshi
authors: T
authors: Suzuki
authors: Department of Nursing, Keio University Hospital, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Electronic address: fc078194@z2.keio.jp.
authors: Taisuke
authors: T
authors: Yasaka
authors: Department of Anesthesiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Electronic address: hiromasa.nagata@vanderbilt.edu.
authors: Hiromasa
authors: H
authors: Nagata
authors: Department of Nursing, Keio University Hospital, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Electronic address: yoko.okamoto@adst.keio.ac.jp.
authors: Yoko
authors: Y
authors: Okamoto
authors: Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. Electronic address: kitak@m.u-tokyo.ac.jp.
authors: Kiyoshi
authors: K
authors: Kita
authors: Department of Anesthesiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Electronic address: morisaki@z8.keio.jp.
authors: Hiroshi
authors: H
authors: Morisaki
mesh_terms: D000203:Activities of Daily Living; D000208:Acute Disease; D000368:Aged; D001510:Bed Rest; D016638:Critical Illness; D005121:Extremities; D005260:Female; D006801:Humans; D007103:Immobilization; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D009133:Muscular Atrophy / Q000209:etiology* / Q000503:physiopathology*; D011446:Prospective Studies; D012307:Risk Factors
keywords: ADL level; Critically ill patients; Early rehabilitation; Immobilisation; Muscle atrophy; Site specificity