TY - JOUR
T1 - Early Detection of Muscle Weakness and Functional Limitations in the Critically Ill
T2 - A Retrospective Evaluation of Bioimpedance Spectroscopy
AU - Baldwin, Claire E
AU - Fetterplace, Kate
AU - Beach, Lisa
AU - Kayambu, Geetha
AU - Paratz, Jennifer
AU - Earthman, Carrie
PY - 2020/7/1
Y1 - 2020/7/1
N2 - Background: The potential for bioimpedance spectroscopy (BIS) to identify muscle weakness and functional limitations in critical illness is unknown; this study aimed to determine association of BIS with strength/function and differences between 3 intensive care units (ICUs). Methods: A retrospective post hoc analysis of BIS, strength, and functional data from adults who required ≥48 hours of mechanical ventilation was conducted. Measures of body composition included the proportion (%) of total body water (TBW), fat mass (FM), and fat-free mass (FFM). The Medical Research Council sum score (MRC-ss) and Physical Function in ICU Test–Scored (PFIT-s) were used for strength and functional assessments. Nonparametric cross-sectional analyses were done at enrollment (≤48 hours of admission: site-A, site-C) and awakening from sedation (site-A, site-B). Raw impedance variables including 50-kHz phase angle (PA) and impedance ratio (IR) were available from site-A and site-B. Results: Participants were 135 adults (site-A n=59, site-B n=33, site-C n=44), with a median (interquartile range) age of 59 (50–69) years. At enrollment, TBW%, FM%, and FFM% were similar between site-A and site-C (P>.05); pooled data were not associated with MRC-ss at awakening or MRC-ss/PFIT-s at ICU discharge. At awakening, there was less TBW%, less FFM%, and greater FM% at site-B vs site-A (P≤.001) but no associations with MRC-ss/PFIT-s when using pooled data. Trends with pooled data of a lower PA and higher IR being associated with awakening MRC-ss were confirmed within site-B (PA ρ=0.70, P≤.001; IR ρ=−0.79, P≤.001). Conclusion: Site-by-site data suggest that raw impedance variables might be useful for screening weakness and poor function.
AB - Background: The potential for bioimpedance spectroscopy (BIS) to identify muscle weakness and functional limitations in critical illness is unknown; this study aimed to determine association of BIS with strength/function and differences between 3 intensive care units (ICUs). Methods: A retrospective post hoc analysis of BIS, strength, and functional data from adults who required ≥48 hours of mechanical ventilation was conducted. Measures of body composition included the proportion (%) of total body water (TBW), fat mass (FM), and fat-free mass (FFM). The Medical Research Council sum score (MRC-ss) and Physical Function in ICU Test–Scored (PFIT-s) were used for strength and functional assessments. Nonparametric cross-sectional analyses were done at enrollment (≤48 hours of admission: site-A, site-C) and awakening from sedation (site-A, site-B). Raw impedance variables including 50-kHz phase angle (PA) and impedance ratio (IR) were available from site-A and site-B. Results: Participants were 135 adults (site-A n=59, site-B n=33, site-C n=44), with a median (interquartile range) age of 59 (50–69) years. At enrollment, TBW%, FM%, and FFM% were similar between site-A and site-C (P>.05); pooled data were not associated with MRC-ss at awakening or MRC-ss/PFIT-s at ICU discharge. At awakening, there was less TBW%, less FFM%, and greater FM% at site-B vs site-A (P≤.001) but no associations with MRC-ss/PFIT-s when using pooled data. Trends with pooled data of a lower PA and higher IR being associated with awakening MRC-ss were confirmed within site-B (PA ρ=0.70, P≤.001; IR ρ=−0.79, P≤.001). Conclusion: Site-by-site data suggest that raw impedance variables might be useful for screening weakness and poor function.
KW - muscle strength
KW - physical function
KW - Standardisation
UR - http://www.scopus.com/inward/record.url?scp=85073986517&partnerID=8YFLogxK
U2 - 10.1002/jpen.1719
DO - 10.1002/jpen.1719
M3 - Article
SN - 0148-6071
VL - 44
SP - 837
EP - 848
JO - JOURNAL OF PARENTERAL AND ENTERAL NUTRITION
JF - JOURNAL OF PARENTERAL AND ENTERAL NUTRITION
IS - 5
ER -