Successive preclinical studies almost without exception show that ventilation with lower tidal volumes reduces the injurious effects of ventilation in animals with uninjured lungs. This finding is in line with results from recent trials in ICU patients without ARDS, demonstrating that ventilation with lower tidal volumes has a strong potential to prevent development of pulmonary complications and maybe even to improve survival. However, evidence mostly comes from nonrandomized clinical trials, and concerns are expressed regarding unselected use of lower tidal volumes in the ICU, that is, in all ventilated critically ill patients, since this strategy could also increase needs for sedation and/or neuromuscular blockade, and maybe even cause respiratory muscle fatigue. These all then could in fact worsen outcome, possibly counteracting the beneficial effects of ventilation with lower tidal volumes.
Monday, February 03, 2014
Low tidal volume ventilation in non-ARDS patients
Physiologic rational and low level evidence point to reduced VILI if low tidal volumes are used, for any indication. This has not been subject to rigorous systematic study, however, and there is concern for unintended consequences, such as greater need for sedation, and the potential for ventilator dyssynchrony. Clinical judgment should ultimately prevail pending high level trials. From a recent review: