Activity Levels in Survivors of the ICU

Abstract

Abstract Objective Limited data exists on the quantification of activity levels and functional status in critically ill patients as they transition from the intensive care unit (ICU) to the wards and subsequently, back into the community. We characterize the physical activity of critically ill patients from their ICU stay until seven days after hospital discharge, as well as correlate physical activity levels with an objective measure of physical function. Methods This prospective observational study of previously independent adults age 55 or older, undergoing mechanical ventilation for up to 7 days, recruited participants at the time of spontaneous breathing trials or < 24 hours after extubation. Participants received an accelerometer at enrollment to wear until one week after discharge. Results Twenty-two participants received accelerometers; 15 were suitable for analysis. Participants were 68 ± 9.6 years old; 47% female. Step counts (mean and 95% CI) were 95 [15–173] in the 3 days before ICU discharge, 257 [114–400] before hospital discharge, 1223 [376–2070] in the first 3 days at home and 1278 [349–2207] between day 4 and 6 post-hospital discharge. Physical activity was significantly higher post- compared to pre-hospital discharge. Short Physical Performance Battery scores (SPPB) were poor at ICU and hospital discharge; however, correlated moderately with physical activity levels immediately upon return home. Conclusions Physical activity remained low as survivors of critical illness transitioned from ICU to hospital wards, but significantly increased upon return to the community. Despite poor SPPB scores at both ICU and hospital discharge, participants were significantly more active immediately after discharge than in their last 3 days of hospitalization. This may represent rapid functional improvement or conversely, constrained physical activity in hospital. Impact This study highlights the need for further evaluation of physical activity constraints in hospital and ways to augment physical activity and function upon discharge. Lay summary Physical activity (step counts) increased modestly as survivors of critical illness transitioned from ICU to hospital wards, but significantly increased upon return to the community. This study highlights the need for further evaluation of physical activity constraints in the hospital setting and ways to augment physical activity and function post-discharge.