Lung- and Diaphragm-Protective Ventilation by Titrating Inspiratory Support to Diaphragm Effort: A Randomized Clinical Trial

 

by de Vries, Heder J.; Jonkman, Annemijn H.; de Grooth, Harm J.; Duitman, Jan Willem.; Girbes, Armand R. J.; Ottenheijm, Coen A. C.; Schultz, Marcus J.; van de Ven, Peter M.; Zhang, Yingrui; de Man, Angelique M. E.; Tuinman, Pieter R.; Heunks, Leo M. A. 

 

Critical Care Medicine: February 2022 - Volume 50 - Issue 2 - p 192-203

 

OBJECTIVES: Lung- and diaphragm-protective ventilation is a novel concept that aims to limit the detrimental effects of mechanical ventilation on the diaphragm while remaining within limits of lung-protective ventilation. The premise is that low breathing effort under mechanical ventilation causes diaphragm atrophy, whereas excessive breathing effort induces diaphragm and lung injury. In a proof-of-concept study, we aimed to assess whether titration of inspiratory support based on diaphragm effort increases the time that patients have effort in a predefined “diaphragm-protective” range, without compromising lung-protective ventilation.

DESIGN: Randomized clinical trial.

SETTING: Mixed medical-surgical ICU in a tertiary academic hospital in the Netherlands.

PATIENTS: Patients (n = 40) with respiratory failure ventilated in a partially-supported mode. INTERVENTIONS: In the intervention group, inspiratory support was titrated hourly to obtain transdiaphragmatic pressure swings in the predefined “diaphragm-protective” range (3–12 cm H2O). The control group received standard-of-care.

MEASUREMENTS AND MAIN RESULTS: Transdiaphragmatic pressure, transpulmonary pressure, and tidal volume were monitored continuously for 24 hours in both groups. In the intervention group, more breaths were within “diaphragm-protective” range compared with the control group (median 81%; interquartile range [64–86%] vs 35% [16–60%], respectively; p < 0.001). Dynamic transpulmonary pressures (20.5 ± 7.1 vs 18.5 ± 7.0 cm H2O; p = 0.321) and tidal volumes (7.56 ± 1.47 vs 7.54 ± 1.22 mL/kg; p = 0.961) were not different in the intervention and control group, respectively.

CONCLUSIONS: Titration of inspiratory support based on patient breathing effort greatly increased the time that patients had diaphragm effort in the predefined “diaphragm-protective” range without compromising tidal volumes and transpulmonary pressures. This study provides a strong rationale for further studies powered on patient-centered outcomes.