Back to Search
Start Over
Higher Levels of Spontaneous Breathing Reduce Lung Injury in Experimental Moderate Acute Respiratory Distress Syndrome*
- Source :
- Critical Care Medicine. 42:e702-e715
- Publication Year :
- 2014
- Publisher :
- Ovid Technologies (Wolters Kluwer Health), 2014.
-
Abstract
- To assess the effects of different levels of spontaneous breathing during biphasic positive airway pressure/airway pressure release ventilation on lung function and injury in an experimental model of moderate acute respiratory distress syndrome.Multiple-arm randomized experimental study.University hospital research facility.Thirty-six juvenile pigs.Pigs were anesthetized, intubated, and mechanically ventilated. Moderate acute respiratory distress syndrome was induced by repetitive saline lung lavage. Biphasic positive airway pressure/airway pressure release ventilation was conducted using the airway pressure release ventilation mode with an inspiratory/expiratory ratio of 1:1. Animals were randomly assigned to one of four levels of spontaneous breath in total minute ventilation (n = 9 per group, 6 hr each): 1) biphasic positive airway pressure/airway pressure release ventilation, 0%; 2) biphasic positive airway pressure/airway pressure release ventilation,0-30%; 3) biphasic positive airway pressure/airway pressure release ventilation,30-60%, and 4) biphasic positive airway pressure/airway pressure release ventilation,60%.The inspiratory effort measured by the esophageal pressure time product increased proportionally to the amount of spontaneous breath and was accompanied by improvements in oxygenation and respiratory system elastance. Compared with biphasic positive airway pressure/airway pressure release ventilation of 0%, biphasic positive airway pressure/airway pressure release ventilation more than 60% resulted in lowest venous admixture, as well as peak and mean airway and transpulmonary pressures, redistributed ventilation to dependent lung regions, reduced the cumulative diffuse alveolar damage score across lungs (median [interquartile range], 11 [3-40] vs 18 [2-69]; p0.05), and decreased the level of tumor necrosis factor-α in ventral lung tissue (median [interquartile range], 17.7 pg/mg [8.4-19.8] vs 34.5 pg/mg [29.9-42.7]; p0.05). Biphasic positive airway pressure/airway pressure release ventilation more than 0-30% and more than 30-60% showed a less consistent pattern of improvement in lung function, inflammation, and damage compared with biphasic positive airway pressure/airway pressure release ventilation more than 60%.In this model of moderate acute respiratory distress syndrome in pigs, biphasic positive airway pressure/airway pressure release ventilation with levels of spontaneous breath higher than usually seen in clinical practice, that is, more than 30% of total minute ventilation, reduced lung injury with improved respiratory function, as compared with protective controlled mechanical ventilation.
- Subjects :
- Spontaneous Breathing
Swine
Ventilator-Induced Lung Injury
Respiratory physiology
Lung injury
Critical Care and Intensive Care Medicine
Severity of Illness Index
Biphasic Positive Airway Pressure
Positive-Pressure Respiration
Airway pressure release ventilation
Random Allocation
Oxygen Consumption
Reference Values
Moderate Acute Respiratory Distress Syndrome
Respiration
Severity of illness
Animals
Medicine
Respiratory Distress Syndrome
Continuous Positive Airway Pressure
Respiratory distress
Pulmonary Gas Exchange
business.industry
Hemodynamics
respiratory system
Respiratory Function Tests
respiratory tract diseases
Disease Models, Animal
Treatment Outcome
Anesthesia
Respiratory Mechanics
Breathing
business
Subjects
Details
- ISSN :
- 00903493
- Volume :
- 42
- Database :
- OpenAIRE
- Journal :
- Critical Care Medicine
- Accession number :
- edsair.doi.dedup.....10c05eff2cc9058d0fa91f594f56a703