Evaluation of an intervention to reduce tidal volumes in ventilated ICU patients

There is considerable evidence that the use of tidal volumes <6 ml kg(-1) predicted body weight (PBW) reduces mortality in mechanically ventilated patients. We evaluated the effectiveness of using a large screen displaying delivered tidal volume in ml kg(-1) (PBW) for reducing tidal volumes.

We assessed the intervention in two 6-month periods. A qualitative study was undertaken after the intervention period to examine staff interaction with the intervention. The study was conducted in a mixed medical and surgical intensive care unit at University Hospitals Bristol, UK. Consecutive patients requiring controlled mechanical ventilation for more than 1 h were included. Alerts were triggered when tidal volume breached predetermined targets and these alerts were visible to ICU clinicians in real time.

A total of 199 patients with 7640 h of data were observed during the control time period and 249 patients with 10 656 h of data were observed in the intervention period. Time spent with tidal volumes <6 ml kg(-1) PBW increased from 17.5 to 28.6% of the period of controlled mechanical ventilation. Time spent with a tidal volume <8 ml kg(-1) PBW increased from 60.6 to 73.9%. The screens were acceptable to staff and stimulated an increase in attendance of clinicians at the bedside to adjust ventilators.

Changing the format of data and displaying it with real-time alerts reduced delivered tidal volumes. Configuring information in a format more likely to result in desired outcomes has the potential to improve the translation of evidence into practice.