Advisory Lead ARDS Respirator Management

Background Lung protective ventilation is a well-established treatment to reduce ventilator-induced lung injury (VILI) in patients suffering from ARDS. To quantify lung protective ventilation the concept of driving pressure (ΔP) and mechanical power were postulated.

Although low tidal volumes and low driving pressures are considered standard of care, it was shown that lung protective ventilation is very little used in ICU patients. Especially in those with a less severe lung disease.

Automated Clinical Decision Support (CDS) systems are gaining more attention in clinical practice. They have been successfully used to increase medical provider adherence to guidelines or local department policy. Another successful means of influencing behavior of medical providers are so called nudge-based interventions. Currently there is little evidence on nudge-type interventions or automated alerts for ventilator settings in the ICU. To our knowledge studies that linked these interventions to a change in patient's outcome are lacking.

Hypothesis Activation of an advisory in the patient data management system accompanied by educational sessions and feedback emails decrease ventilation driving pressure in mechanically ventilated patients at increased risk of ARDS (LIPS ≥ 4). As secondary outcome parameters, incidence of ARDS, ventilator free days, reintubation rate, length of stay in the ICU or the hospital and mortality at day 28 will be evaluated.

Methods As an advisory is activated in the ICU software, medical staff caring for the patients can't be blinded. Therefore, the trial will be conducted as observational cohort trial. During the first six month all patients with a LIPS ≥ 4 will be included in the control group. No change of care is needed. In a second phase during the next six months, all patients with a LIPS ≥ 4 will be included into the alert group where advisories will be shown in the patient data management system.

To create this advisory, a clinical advisory rule is executed every 4 hours and the appropriate advisory text is calculated. If the defined threshold values (driving pressure ≥ 15mbar) are reached, then the advisory displays a recommendation to rethink the patient's ventilation strategy. Furthermore, permissive hypercapnia and oxygen saturating limits considered as safe will be given. (paCO2: 55mmHg, pH: 7.25, paO2: 80 mmHg, SaO2: 92%)

Outcome The primary outcome is an improvement of medical stuff's adherence to current recommendations shown by a reduction of the mean ventilator driving pressure (by using the AUC of driving pressures).

The secondary outcomes are ventilator free days, 28-day mortality, reintubation rate, incidence of ARDS and length of stay in the ICU and the hospital.

Inclusion criteria

• LIPS >= 4, ventilated invasively at point of screening

Exclusion criteria

• ARDS at admission
• Pregnant patients
• Age < 18 years
• Patients with elevated intracranial pressure