title: Ultrasonography in the intensive care setting can be used to detect changes in the quality and quantity of muscle and is related to muscle strength and function.
abstract: OBJECTIVE
  This study aimed to (1) document patterns of quadriceps muscle wasting in the first 10 days of admission and (2) determine the relationship between muscle ultrasonography and volitional measures.
  
  
  METHODS
  Twenty-two adults ventilated for more than 48 hours were included. Sequential quadriceps ultrasound images were obtained over the first 10 days and at awakening and intensive care unit (ICU) discharge. Muscle strength and function were assessed at awakening and ICU discharge.
  
  
  RESULTS
  A total of 416 images were analyzed. There was a 30% reduction in vastus intermedius (VI) thickness, rectus femoris (RF) thickness, and cross-sectional area within 10 days of admission. Muscle echogenicity scores increased for both RF and VI muscles by +12.7% and +25.5%, respectively (suggesting deterioration in muscle quality). There was a strong association between function and VI thickness (r = 0.82) and echogenicity (r = -0.77). There was a moderate association between function and RF cross-sectional area (r = 0.71).
  
  
  CONCLUSIONS
  Muscle wasting occurs rapidly in the ICU setting. Ultrasonography is a useful surrogate measure for identifying future impairment. Vastus intermedius may be an important muscle to monitor in the future because it demonstrated the greatest change in muscle quality and had the strongest relationship to volitional measures.
authors.affiliation: Department of Physiotherapy, The University of Melbourne, Victoria, Australia. Electronic address: selina.parry@unimelb.edu.au.
authors.forename: Selina M
authors.initials: SM
authors.lastname: Parry
authors.affiliation: Department of Physiotherapy, The University of Melbourne, Victoria, Australia.
authors.forename: Doa
authors.initials: D
authors.lastname: El-Ansary
authors.affiliation: Department of Neurology, Wake Forest School of Medicine, Winston-Salem, NC, USA.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Cartwright
authors.affiliation: Department of Neurology, Wake Forest School of Medicine, Winston-Salem, NC, USA.
authors.forename: Aarti
authors.initials: A
authors.lastname: Sarwal
authors.affiliation: Department of Physiotherapy, Austin Health, Melbourne, Australia.
authors.forename: Sue
authors.initials: S
authors.lastname: Berney
authors.affiliation: Department of Physiology, The University of Melbourne, Victoria, Australia.
authors.forename: René
authors.initials: R
authors.lastname: Koopman
authors.affiliation: Department of Physiotherapy, The University of Melbourne, Victoria, Australia; CAPES Foundation, Ministry of Education of Brazil, Brasília, DF, Brazil.
authors.forename: Raquel
authors.initials: R
authors.lastname: Annoni
authors.affiliation: Division of Respiratory and Critical Care Medicine, National University Health System, Singapore.
authors.forename: Zudin
authors.initials: Z
authors.lastname: Puthucheary
authors.affiliation: Statistical Consulting Centre, The University of Melbourne, Victoria, Australia.
authors.forename: Ian R
authors.initials: IR
authors.lastname: Gordon
authors.affiliation: Department of Pulmonology and Critical Care, Wake Forest School of Medicine, Winston-Salem, NC, USA.
authors.forename: Peter E
authors.initials: PE
authors.lastname: Morris
authors.affiliation: Department of Physiotherapy, The University of Melbourne, Victoria, Australia.
authors.forename: Linda
authors.initials: L
authors.lastname: Denehy
mesh_terms: D003422:Critical Care / Q000379:methods; D016638:Critical Illness; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D010351:Patient Discharge; D011446:Prospective Studies; D052097:Quadriceps Muscle / Q000000981:diagnostic imaging* / Q000502:physiology; D014463:Ultrasonography; D019282:Wasting Syndrome / Q000000981:diagnostic imaging*
keywords: Critical illness; Echogenicity; Intensive care; Intensive care unit–acquired weakness; Muscle wasting; Ultrasound