Prognostic value of day 10 mobilization status for ambulation at hospital discharge in critically ill patients: a historical cohort study in Japan

Background: Critically ill patients often have long-lasting limitations in activities of daily living, particularly in walking ability. Although early mobilization increases the likelihood of independent ambulation at hospital discharge, the timing at which different mobilization levels become associated with ambulatory recovery is unclear. This study describes the timing for achieving several mobilization levels and its associations with ambulatory recovery at hospital discharge. Methods: In this single-center retrospective cohort study, patients were divided into a regained group, composed of patients whose ambulation recovered to pre-intensive care unit (ICU) admission levels by hospital discharge, and a non-regained group. Multivariable logistic regression analyses and receiver operating characteristic curve analyses were performed to examine the association between the timing of mobilization (standing, marching in place, and assisted walking) and regained ambulation at hospital discharge. Results: In total, 295 patients were included, and 223 (76%) of them had regained ambulation at hospital discharge. The adjusted odds ratio for standing peaked on day 10 after ICU admission (odds ratio, 5.61; 95% CI, 2.21-17.76) and declined thereafter. The optimal cutoff time linking marching in place and walking with assistance to regained ambulation was also day 10 after ICU admission (marching in place: area under the curve [AUC], 0.78; sensitivity, 0.83; specificity, 0.64; and walking with assistance: AUC, 0.79; sensitivity, 0.77; specificity, 0.68). Conclusions: The findings suggest that mobility status on day 10 after ICU admission can serve as a pragmatic marker for identifying patients at risk of poor ambulatory recovery.