A novel large animal model of smoke inhalation-induced acute respiratory distress syndrome

Authors

Premila D. Leiphrakpam, University of Nebraska Medical Center
Hannah R. Weber, University of Nebraska Medical Center
Andrea McCain, University of Nebraska - LincolnFollow
Roser Romaguera Matas, University of Nebraska - Lincoln
Ernesto Martinez Duarte, University of Nebraska Medical Center
Keely L. Buesing, University of Nebraska Medical Center

ORCID IDs

Keely L. Buesing

Document Type

Article

Date of this Version

2021

Citation

Leiphrakpam et al. Respir Res (2021) 22:198 https://doi.org/10.1186/s12931-021-01788-8

Comments

OPEN ACCESS

Abstract

Background: Acute respiratory distress syndrome (ARDS) is multifactorial and can result from sepsis, trauma, or pneumonia, amongst other primary pathologies. It is one of the major causes of death in critically ill patients with a reported mortality rate up to 45%. The present study focuses on the development of a large animal model of smoke inhalation-induced ARDS in an effort to provide the scientific community with a reliable, reproducible large animal model of isolated toxic inhalation injury-induced ARDS. Methods: Animals (n=21) were exposed to smoke under general anesthesia for 1 to 2 h (median smoke exposure=0.5 to 1 L of oak wood smoke) after the ultrasound-guided placement of carotid, pulmonary, and femoral artery catheters. Peripheral oxygen saturation (SpO₂), vital signs, and ventilator parameters were monitored throughout the procedure. Chest x-ray, carotid, femoral and pulmonary artery blood samples were collected before, during, and after smoke exposure. Animals were euthanized and lung tissue collected for analysis 48 h after smoke inhalation. Results: Animals developed ARDS 48 h after smoke inhalation as reflected by a decrease in SpO2 by approximately 31%, PaO₂/FiO₂ ratio by approximately 208 (50%), and development of bilateral, diffuse infiltrates on chest x-ray. Study animals also demonstrated a significant increase in IL-6 level, lung tissue injury score and wet/dry ratio, as well as changes in other arterial blood gas (ABG) parameters. Conclusions: This study reports, for the first time, a novel large animal model of isolated smoke inhalation-induced ARDS without confounding variables such as cutaneous burn injury. Use of this unique model may be of benefit in studying the pathophysiology of inhalation injury or for development of novel therapeutics.