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bioRxiv · 10.1101/2023.10.16.562610

Dysphagia as a missing link between post-surgical- and opioid-related pneumonia

Frazure, M.·Greene, C. L.·Iceman, K.·Howland, D. R.·Pitts, T.
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Abstract

ObjectivePostoperative pneumonia remains a common complication of surgery, despite increased attention. The purpose of our study was to determine the effects of routine surgery and post-surgical opioid administration on airway protection risk. MethodsEight healthy adult cats were evaluated for dysphagia in 2 experiments. 1) In 4 female cats airway protection status was tracked following routine abdominal surgery (spay surgery) plus low-dose opioid administration (buprenorphine 0.015mg/kg, IM, q8-12h; n=5). 2) Using a cross-over design (2 male, 2 female) cats were treated with moderate (0.02mg/kg) or high (0.04mg/kg) dose buprenorphine (IM, q8-12h; n=5) to determine changes in airway protection status or evidence of dysphagia. ResultsAirway protection was significantly affected in both experiments, but most severely post-surgically where 75% of the animals exhibited silent aspiration. ConclusionOropharyngeal swallow is impaired by the partial mu-opioid receptor agonist buprenorphine, most remarkably in the post-operative setting. These findings have implications for the prevention and management of aspiration pneumonia in vulnerable populations.

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Frazure, M., Greene, C. L., Iceman, K., Howland, D. R., Pitts, T.. 2023-10-19. Dysphagia as a missing link between post-surgical- and opioid-related pneumonia. https://doi.org/10.1101/2023.10.16.562610

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