Periodic Fluctuation of Tidal Volumes Further Improves Variable Ventilation in Experimental Acute Respiratory Distress Syndrome

Frontiers in Physiology

Alessandro Beda¹  Nadja C. Carvalho¹  Thomas Kiss²  Andreas Güldner²  Robert Huhle²  Marcelo G. de Abreu²  Thomas Bluth²  Sarah Kerber²  Ines Rentzsch³  Paolo Pelosi⁴  Michael Kasper⁵ 

[1] Departamento de Engenharia Eletrônica, Federal University of Minas Gerais, Belo Horizonte, Brazil;Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany;Department of Orthodontics, Technische Universität Dresden, Dresden, Germany;Department of Surgical Sciences and Integrated Diagnostics, IRCCS San Martino IST, University of Genoa, Genoa, Italy;Institute of Anatomy, Technische Universität Dresden, Dresden, Germany;

关键词: experimental model;    acute respiratory distress syndrome;    mechanical ventilation;    variable ventilation;    gas exchange;    respiratory mechanics;   

DOI  :  10.3389/fphys.2018.00905

来源: DOAJ

【 摘 要 】

In experimental acute respiratory distress syndrome (ARDS), random variation of tidal volumes (VT) during volume controlled ventilation improves gas exchange and respiratory system mechanics (so-called stochastic resonance hypothesis). It is unknown whether those positive effects may be further enhanced by periodic VT fluctuation at distinct frequencies, also known as deterministic frequency resonance. We hypothesized that the positive effects of variable ventilation on lung function may be further amplified by periodic VT fluctuation at specific frequencies. In anesthetized and mechanically ventilated pigs, severe ARDS was induced by saline lung lavage and injurious VT (double-hit model). Animals were then randomly assigned to 6 h of protective ventilation with one of four VT patterns: (1) random variation of VT (WN); (2) P04, main VT frequency of 0.13 Hz; (3) P10, main VT frequency of 0.05 Hz; (4) VCV, conventional non-variable volume controlled ventilation. In groups with variable VT, the coefficient of variation was identical (30%). We assessed lung mechanics and gas exchange, and determined lung histology and inflammation. Compared to VCV, WN, P04, and P10 resulted in lower respiratory system elastance (63 ± 13 cm H2O/L vs. 50 ± 14 cm H2O/L, 48.4 ± 21 cm H2O/L, and 45.1 ± 5.9 cm H2O/L respectively, P < 0.05 all), but only P10 improved PaO2/FIO2 after 6 h of ventilation (318 ± 96 vs. 445 ± 110 mm Hg, P < 0.05). Cycle-by-cycle analysis of lung mechanics suggested intertidal recruitment/de-recruitment in P10. Lung histologic damage and inflammation did not differ among groups. In this experimental model of severe ARDS, periodic VT fluctuation at a frequency of 0.05 Hz improved oxygenation during variable ventilation, suggesting that deterministic resonance adds further benefit to variable ventilation.

【 授权许可】

Unknown