title: Quantitative neuromuscular ultrasound in intensive care unit-acquired weakness: A systematic review.
abstract: Intensive care unit-acquired weakness (ICU-AW) causes significant morbidity and impairment in critically ill patients. Recent advances in neuromuscular ultrasound (NMUS) allow evaluation of neuromuscular pathology early in critical illness. Here we review application of ultrasound in ICU-AW. MEDLINE-indexed articles were searched for terms relevant to ultrasound and critical illness. Two reviewers evaluated the resulting abstracts (n = 218) and completed full-text review (n = 13). Twelve studies and 1 case report were included. Ten studies evaluated muscle thickness or cross-sectional area (CSA): 8 reported a decrease, and 2 reported no change. Two studies reported preservation of muscle thickness in response to neuromuscular electrical stimulation, and 1 found no preservation. One study found decreases in gray-scale standard deviation, but no change in echogenicity. One study described increases in echogenicity and fasciculations. Ultrasound reliability in ICU-AW is not fully established. Further investigation is needed to identify ultrasound measures that reliably predict clinical, electrodiagnostic, and pathologic findings of ICU-AW.
authors.affiliation: Department of Physical Medicine and Rehabilitation, University of Washington, Harborview Medical Center, Seattle, Box, 359740, 325, 9th Avenue, Washington, 98104, USA.
authors.forename: Aaron
authors.initials: A
authors.lastname: Bunnell
authors.affiliation: School of Oral Health Sciences, University of Washington, Harborview Medical Center, Seattle, Washington, USA.
authors.forename: John
authors.initials: J
authors.lastname: Ney
authors.affiliation: Department of Physical Medicine and Rehabilitation, University of Washington, Harborview Medical Center, Seattle, Box, 359740, 325, 9th Avenue, Washington, 98104, USA.
authors.forename: Alfred
authors.initials: A
authors.lastname: Gellhorn
authors.affiliation: Department of Pulmonary Medicine, University of Washington, Harborview Medical Center, Seattle, Washington, USA.
authors.forename: Catherine L
authors.initials: CL
authors.lastname: Hough
mesh_terms: D000818:Animals; D016638:Critical Illness / Q000628:therapy; D006801:Humans; D007362:Intensive Care Units; D018908:Muscle Weakness / Q000000981:diagnostic imaging* / Q000209:etiology; D009469:Neuromuscular Junction / Q000000981:diagnostic imaging*; D014463:Ultrasonography
keywords: critical illness; critical illness myopathy; critical illness polyneuropathy, intensive care unit acquired weakness; quantitative neuromuscular ultrasound