  Early mobilization of critically ill patients in the Intensive Care Unit
(ICU) can prevent adverse outcomes such as delirium and post-discharge physical
impairment. To date, no studies have characterized activity of sepsis patients
in the ICU using granular actigraphy data. This study characterizes the
activity of sepsis patients in the ICU to aid in future mobility interventions.
We have compared the actigraphy features of 24 patients in four groups: Chronic
Critical Illness (CCI) sepsis patients in the ICU, Rapid Recovery (RR) sepsis
patients in the ICU, non-sepsis ICU patients (control-ICU), and healthy
subjects. We used several statistical and circadian rhythm features extracted
from the patients' actigraphy data collected over a five-day period. Our
results show that the four groups are significantly different in terms of
activity features. In addition, we observed that the CCI and control-ICU
patients show less regularity in their circadian rhythm compared to the RR
patients. These results show the potential of using actigraphy data for guiding
mobilization practices, classifying sepsis recovery subtype, as well as for
tracking patients' recovery.
