Which is the ideal tidal volume for patients in ICU without ARDS who need mechanical ventilation more than 24h?

Abstract

Invasive ventilation, one of the most frequently applied strategies in the intensive care unit (ICU), is increasingly recognized as a potentially harmful intervention. There is evidence that lung-protective ventilation using low tidal volumes improves survival in patients with acute respiratory distress syndrome (ARDS), but it is less certain whether tidal volume restriction benefits patients without ARDS. Two randomized clinical trials found tidal volume reduction to be associated with a lower number of pulmonary complications in patients without ARDS, and 2 individual patient data meta-analyses suggested that tidal volume reduction may shorten the time spent on the ventilator and duration of stay in the ICU and hospital.

However, the use of low tidal volumes could lead to an in- creased need for sedation because of higher respiratory rate or patient-ventilator asynchrony and, possibly, self- inflicted lung injury due to compensatory injurious inspiratory efforts. In addition, it has been suggested that low tidal volumes may increase the risk of delirium.

The Protective Ventilation in Patients Without ARDS (PReVENT) trial was conducted to test whether a ventilation strategy using low tidal volumes is superior to a ventilation strategy using intermediate tidal volumes with respect to the number of ventilator-free days and alive at day.