Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Observational Study
. 2025 May;30(3):e70018.
doi: 10.1111/nicc.70018.

An optimal cut-off point for the Chelsea Critical Care Physical Assessment Tool to diagnose intensive care unit-acquired weakness in patients with mechanical ventilation: A multicentre observational study

Yuchen Wu  1   2   3 , Yatao Liu  2   3 , Guoqiang Wang  2   3 , Ang Zheng  4 , Zhigang Zhang  2   3 , Huaping Wei  2   3 , Xin Wang  1   5
Affiliations
Observational Study

An optimal cut-off point for the Chelsea Critical Care Physical Assessment Tool to diagnose intensive care unit-acquired weakness in patients with mechanical ventilation: A multicentre observational study

Yuchen Wu et al. Nurs Crit Care. 2025 May.

Abstract

Background: The Chelsea Critical Care Physical Assessment Tool (CPAx) may be an optimal tool for diagnosing intensive care unit-acquired weakness (ICU-AW). However, we do not know the cut-off point for the diagnosis of ICU-AW.

Aim: To ascertain the best cut-off point for CPAx to diagnose ICU-AW in adult patients with mechanical ventilation.

Study design: A multicentre, prospective cross-sectional study. Participants were recruited from five ICUs in China that ranged from 20 June 2021 to 31 July 2023. The Medical Research Council Sum Scale (MRC-ss) <48 was taken as the standard to calculate the area under the curve (AUC) of CPAx. The cut-off point was determined by the maximum value of Youden Index (YImax). The kappa (κ) test was used to test the consistency of the MRC-ss and CPAx.

Results: The AUC at baseline, weaning and discharge time point was 0.87 (95% CI 0.81-0.93), 0.96 (95% CI 0.92-0.99) and 0.91 (95% CI 0.86-0.96), respectively. Correspondingly, The YImax was 0.62, 0.91 and 0.65. The best cut-off point of CPAx score to diagnose ICU-AW at baseline, weaning and discharge time point was 30.5 (sensitivity = 72%, specificity = 89%), 31.5 (sensitivity = 95%, specificity = 90%) and 31.5 (sensitivity = 94%, specificity = 71%), respectively. Due to the CPAx being an ordinal scale, it was determined preliminarily that the cut-off point for the CPAx to diagnose ICU-AW was 31 points. We took CPAx ≤31 and MRC-ss <48 as criteria to diagnose ICU-AW and test the consistency of MRC-ss and CPAx. The results showed that there was no significant difference in the incidence of ICU-AW at different time points.

Conclusions: The optimal cut-off point for the CPAx to diagnose ICU-AW is a score of 31 and it has good sensitivity and specificity.

Relevance to clinical practice: The CPAx ≤31 score to diagnose ICU-acquired weakness (ICU-AW) has good sensitivity and specificity, and it can help to predict the risk of ICU-AW and guide medical personnel to make interventions.

Keywords: critical care nursing; intensive care unit; mechanical ventilation; muscle weakness; sensitivity and specificity.

PubMed Disclaimer

References

REFERENCES

    1. Piva S, Fagoni N, Latronico N. Intensive care unit‐acquired weakness: unanswered questions and targets for future research. F1000Res. 2019;8:508. doi:10.12688/f1000research.17376.1
    1. Batt J, Dos Santos CC, Cameron JI, Herridge MS. Intensive care unit‐acquired weakness: clinical phenotypes and molecular mechanisms. Am J Respir Crit Care Med. 2013;187(3):238‐246. doi:10.1164/rccm.201205‐0954SO
    1. Panahi A, Malekmohammad M, Soleymani F, Hashemian SM. The prevalence and outcome of intensive care unit acquired weakness (ICUAW). Tanaffos. 2020;19(3):250‐255.
    1. Kemp HI, Laycock H, Costello A, Brett SJ. Chronic pain in critical care survivors: a narrative review. Br J Anaesth. 2019;123(2):372‐384. doi:10.1016/j.bja.2019.03.025
    1. Appleton RT, Kinsella J, Quasim T. The incidence of intensive care unit‐acquired weakness syndromes: a systematic review. J Intensive Care Soc. 2015;16(2):126‐136. doi:10.1177/1751143714563016

Publication types

LinkOut - more resources