Variables associated with mobility levels in critically ill patients: A cohort study

Early mobilization in the intensive care unit (ICU) helps improve patients' functional status at discharge. However, many barriers hinder this practice.

To identify mobility levels acquired by critically ill patients and their variables.

A multi-centre cohort study was conducted in adult patients receiving invasive mechanical ventilation for at least 48 hours.

The primary outcome was level of mobility according to the ICU mobility scale. The secondary outcome was human resource availability and existence of ABCDEF bundle guidelines. A logistic regression was performed, based on days 3 to 5 of the ICU stay and significant association with active mobility.

Six hundred and forty-two patients were included from 80 ICUs. Active moving in and out of bed was found on 9.9% of patient-days from day 8 of the ICU stay. Bed exercises, or passive transfers, and immobility were observed on 45.6% and 42.2% of patient-days, respectively. Patients achieving active mobility (189/642, 29.4%) were in ICUs with more physiotherapist hours. Active mobility was more likely with a 1:4 nurse-patient ratio (odds ratio [OR] 3.7 95% confidence interval [CI] [1.2-11.2]), high MRC sum-score (OR 1.05 95% CI [1.04-1.06]) and presence of delirium (OR 1.01 95% CI [1.00-1.02]). By contrast, active mobility was hindered by higher BMI (OR 0.92 95% CI [0.88-0.97]), a 1:3 nurse-patient ratio (OR 0.54 95% CI [0.32-0.93]), or a shift-dependent nurse-patient ratio (OR 0.27 95% CI [0.12-0.62]).

Immobility and passive mobilization were prevalent. A high MRC sum-score and presence of delirium are protective factors of mobilization. A 1:4 nurse-patient ratio shows a stronger association with active mobility than a 1:3 ratio.

Severity-criteria-based nurse-patient ratios hinder mobilization. Active mobilization may be enhanced by using nursing-intervention-based ratios, increasing physiotherapist hours, and achieving wider application of the ABCDEF bundle, resulting in more awake, cooperative patients.