Lung protective mechanical ventilation strategies in cardiothoracic critical care: a retrospective study

Papworth Hospital undertook a retrospective chart review and tested the hypothesis that tidal volume is a predictor of mortality in cardiothoracic (medical and surgical) critical care patients receiving invasive mechanical ventilation (MV). Additional aims were to 1)  identify the commonly used ventilatory modes and parameters in our cardiothoracic ICU (postoperative and nonsurgical patients), 2)  identify whether certain components of lung protective ventilation care bundles are followed by our institution’s cardiac intensivists at the onset of MV, 3) help develop a ventilatory guideline within our cardiac ICU and cardiac recovery unit and integrate a ventilator bundle in checklist format in the MetaVision clinical information system and 4) organise teaching sessions on lung protective strategies for all ICU medical, nursing, and allied health professionals. Predictor variables in the first 24 hours extracted from MetaVision included sequential organ failure assessment (SOFA) score at the onset of MV, ventilator mode, types of surgery (cardiac/thoracic, transplant, and nonsurgical) and more. The authors found that when controlling for covariates, Vt and other ventilator variables did not independently predict mortality in our model, despite best evidence suggesting that they should. The Berlin Definition of ARDS severity categorises patients on their degree of hypoxemia (mild, moderate, and severe based on PaO2:FiO2 ratio) which should predict mortality, but the authors did not sample equally from each of these groups and conclude, “As a result, our study was not adequately powered to detect a difference in mortality between these groups and therefore our results are not definitive. Further study of this sample would add the required power or use subgroup analyses to determine all factors contributing to death.”

About the author

Gil Ben-Horin Jacob Krygier is a Clinical Application Specialist at iMDsoft with 20 years of hands-on healthcare experience. His background spans operating rooms, intensive care units, emergency medicine, and medivac air ambulances, with specialized expertise in anesthesia and emergency care.