Effects of Anesthesia on Ozone-Induced Lung and Systemic Inflammation

Abstract

Anesthetics are required for procedures that deliver drugs/biologics, infectious/inflammatory agents, and toxicants directly to the lungs. However, the possible confounding effects of anesthesia on lung inflammation and injury are underreported. Here, we tested the effects of brief isoflurane (Iso) or ketamine/xylazine/atipamezole (K/X/A) anesthesia prior to ozone exposure (4 hours, 3ppm) on lung inflammatory responses in mice. Anesthesia regimens modeled those used for non-surgical intratracheal instillations, and were administered 1-2 hours or 24 hours prior to initiating ozone exposure. We found that Iso given 1-2 hours prior to ozone inhibited inflammatory responses in the lung, and this effect was absent when Iso was given 23-24 hours prior to ozone. In contrast, K/X/A given 1-2 hours prior to ozone increased lung and systemic inflammation. Our results highlight the need to comprehensively evaluate anesthesia as an experimental variable in the assessment of lung inflammation in response to ozone and other inflammatory stimuli.