This study aims to investigate whether an actigraph, measuring in-hospital activity, used for a week after discharge from the ICU at Zealand University Hospital Køge, can predict physical function at three-month follow up.

The hospital activity will be measured with actigraphy, a measurement tool that quantifies activity level. The activity will be measured for 7 days after ICU discharge. The actigraph is to be worn as a bracelet.

The physical function will be measured with Chelsea Critical Care Physical Assessment Tool (CPAx). CPAx is assessed at ICU discharge and after three months.

Treatment at an Intensive Care Unit (ICU) is often needed for the survival of critically ill patients, but it can take a long time to recover. A number of high quality studies have shown that patients experience functional impairments for a long period after discharge, even for years.

These patients may suffer from a number of other negative influences of their critical illness and ICU stay, e.g. memory problems, episodes of depression, cognitive dysfunction and sleeping disorders. These symptoms are seen in both medical and surgical patients and has been named the Post Intensive Care Syndrome.

Physical rehabilitation is important and must start already during admission, in order to regain some of the function and independence of the patients. This has a well documented effect on both mental and physical wellbeing.

Actigraphy is a newer way of quantifying the activity level continuously. It is validated and has been used in the ICU to assess agitation and sedation and in an oncological, surgical and even an ICU population to assess sleep.

It is easy to use, non-invasive and inexpensive. It is worn like a bracelet and doesn't impair the patients mobility or ambulation.

Another issue when evaluating physical impairments is the choice of method for assessing physical function. For this study, the investigators use the Chelsea Critical Care Physical Assessment Tool (CPAx) as it has good validity and clinimetric properties and is easy to use. Also, it can be done as part of the daily training as it is developed specifically for the ICU.

The aim of this study is to investigate how the in-hospital activity level of patients after ICU discharge is associated with their physical function at three months post discharge.

Inclusion Criteria:

• Patients > 18 years of age
• Admitted to the ICU for > 24 h

Exclusion Criteria:

• Not able to speak and understand Danish
• Patients suffering from dementia or psychosis
• Discharged from the ICU to terminal care
• Patients transferred to another hospital during ICU stay
• Patients living outside the Region of Zealand
• Patients suffering from total paralysis before admission

Patients admitted to the ICU at Zealand University Hospital, Køge, in the study period