Real-time effects of lateral positioning on regional ventilation and perfusion in an experimental model of acute respiratory distress syndrome

Frontiers in Physiology

Physiology

Otomar Kittnar¹  Leoš Tejkl¹  Eduard Kuriščák¹  João Batista Borges¹  Mikuláš Mlček¹  Michal Otáhal²  Dominik Hladík²  Glasiele Cristina Alcala³  Marcelo Amato³ 

[1] First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia;First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia;Department of Anaesthesiology, Resuscitation and Intensive Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia;Pulmonology Division, Cardiopulmonary Department, Heart Institute, University of Sao Paulo, São Paulo, Brazil;

关键词: acute respiratory disease syndrome;    mechanical ventilation;    body position changes;    ventilator-induced lung injury;    lung collapse;   

DOI  :  10.3389/fphys.2023.1113568

 received in 2022-12-01, accepted in 2023-03-01,  发布年份 2023

来源: Frontiers

【 摘 要 】

Low-volume lung injury encompasses local concentration of stresses in the vicinity of collapsed regions in heterogeneously ventilated lungs. We aimed to study the effects on ventilation and perfusion distributions of a sequential lateral positioning (30°) strategy using electrical impedance tomography imaging in a porcine experimental model of early acute respiratory distress syndrome (ARDS). We hypothesized that such strategy, including a real-time individualization of positive end-expiratory pressure (PEEP) whenever in lateral positioning, would provide attenuation of collapse in the dependent lung regions. A two-hit injury acute respiratory distress syndrome experimental model was established by lung lavages followed by injurious mechanical ventilation. Then, all animals were studied in five body positions in a sequential order, 15 min each: Supine 1; Lateral Left; Supine 2; Lateral Right; Supine 3. The following functional images were analyzed by electrical impedance tomography: ventilation distributions and regional lung volumes, and perfusion distributions. The induction of the acute respiratory distress syndrome model resulted in a marked fall in oxygenation along with low regional ventilation and compliance of the dorsal half of the lung (gravitational-dependent in supine position). Both the regional ventilation and compliance of the dorsal half of the lung greatly increased along of the sequential lateral positioning strategy, and maximally at its end. In addition, a corresponding improvement of oxygenation occurred. In conclusion, our sequential lateral positioning strategy, with sufficient positive end-expiratory pressure to prevent collapse of the dependent lung units during lateral positioning, provided a relevant diminution of collapse in the dorsal lung in a porcine experimental model of early acute respiratory distress syndrome.

【 授权许可】

Unknown   
Copyright © 2023 Mlček, Borges, Otáhal, Alcala, Hladík, Kuriščák, Tejkl, Amato and Kittnar.