Introduction
Intensive Care Unit-Acquired Weakness (ICU-AW) is a significant complication affecting individuals who survive critical illness. This condition leads to generalized muscle weakness and functional impairments, impacting patient recovery and long-term well-being. While subjective assessments of ICU-AW are common, the need for objective measurement tools is increasingly recognized to better understand and manage this condition. This study aimed to investigate the construct validity of the Chelsea Critical Care Physical Assessment Tool (CPAx) by examining the relationship between CPAx scores and patient discharge location, a key indicator of functional outcome following critical care.
Methods
The CPAx was implemented as a service improvement initiative within an 11-bed Intensive Care Unit (ICU). Data was collected prospectively on patients admitted to the ICU for more than 48 hours, between May 10, 2010, and November 13, 2013. For each patient (n = 499), the final CPAx score recorded within 24 hours prior to ICU discharge or death was analyzed. Upon hospital discharge, patients were categorized into seven groups based on their ongoing rehabilitation and care requirements. Statistical analysis was then performed to determine the association between CPAx scores at ICU discharge and the location of hospital discharge, utilizing descriptive statistics to explore these relationships between groups.
Results
The study included 499 patients, revealing diverse discharge outcomes. A significant portion, 171 patients (34.3%), were discharged home without needing further rehabilitation or care services. Another 131 patients (26.2%) required community-based support, while 28 patients (5.6%) were admitted to inpatient rehabilitation facilities for intensive 6-week programs. A smaller subset, 27 patients (5.4%), needed nursing home level care. Sadly, 80 patients (16.0%) died while in the ICU, and a further 37 patients (7.4%) died during their hospital stay after ICU discharge. Statistical analysis demonstrated a significant difference in the median CPAx scores across these discharge groups (P<0.0001), indicating a correlation between CPAx score and discharge disposition.
Conclusion
This study provides evidence for the construct validity of the CPAx score as a critical care physical assessment tool. The CPAx effectively differentiated between patient groups with varying functional needs at the time of hospital discharge. The tool demonstrated limited floor and ceiling effects among survivors of critical illness, suggesting its applicability across a range of patient functional levels. The findings highlight that a substantial proportion of patients recovering from critical illness require ongoing post-discharge care and rehabilitation services, underscoring the importance of early and objective functional assessment using tools like the CPAx to guide care planning and resource allocation.
