Journal
INTENSIVE CARE MEDICINE
Volume 37, Issue 12, Pages 1913-1920Publisher
SPRINGER
DOI: 10.1007/s00134-011-2388-9
Keywords
Ventilator-induced lung injury; Mechanical ventilation; Lung stress; Lung strain; Comparative physiology
Categories
Funding
- Fondazione Fiera di Milano for Translational and Competitive Research
Ask authors/readers for more resources
To investigate ventilator-induced lung injury (VILI), several experimental models were designed including different mammalian species and ventilator settings, leading to a large variability in the observed time-course and injury severity. We hypothesized that the time-course of VILI may be fully explained from a single perspective when considering the insult actually applied, i.e. lung stress and strain. Studies in which healthy animals were aggressively ventilated until preterminal VILI were selected via a Medline search. Data on morphometry, ventilator settings, respiratory function and duration of ventilation were derived. For each animal group, lung stress (transpulmonary pressure) and strain (end-inspiratory lung inflation/lung resting volume ratio) were estimated. From the Medline search 20 studies including five mammalian species (sheep, pigs, rabbits, rats, mice) were selected. Time to achieve preterminal VILI varied widely (18-2,784 min), did not correlate with either tidal volume (expressed in relation to body weight) or airway pressure applied, but was weakly associated with lung stress (r (2) = 0.25, p = 0.008). In contrast, the duration of mechanical ventilation was closely correlated with both lung strain (r (2) = 0.85, p < 0.0001) and lung strain weighted for the actual time of application during each breath (r (2) = 0.83, p < 0.0001), according to exponential decay functions. When it was normalized for the lung strain applied, larger species showed a greater resistance to VILI than smaller species (medians, 25th-75th percentiles: 690, 460-2,001 min vs. 16, 4-59 min, respectively; p < 0.001). Lung strain may play a critical role as a unifying rule describing the development of VILI among mammals with healthy lungs.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available