High Flow Nasal Oxygen: Impact on Aspiration and the Care of Medically Complex Patients

BackgroundIdentifying aspiration is an under-recognized component to reducing a patient's hospital length of stay, reducing hospital costs and lessening mortality risk. Given increased utilization of High Flow Nasal Oxygen (HFNO) and limited evidence identifying impacts of HFNO on swallowing and aspiration, our study contributes to determining the correlation between aspiration and HFNO.Research QuestionsDoes HFNO increase the odds of aspiration or silent aspiration? Do proportions of patients who exhibit aspiration or silent aspiration differ at different levels of oxygen support?Study Design and MethodsAn observational retrospective cohort study of a prospectively collected database of 910 adult patients from December 2020 - October 2022 treated with HFNO.ResultsMultivariable logistic regression modeling showed HFNO was not significantly associated with PAS 5-8, thin liquids (adjusted OR: 1.09, p = .702) nor significantly associated with PAS 8, thin liquids (adjusted OR: 1.04, p = .880). However, deep unsensed penetration and aspiration ranged from 48%-86% across all oxygen flow rate levels with a higher proportion of patients silently aspirating while on the 10-20L/min flow rate of oxygen.InterpretationWhile our findings did not find HFNO to be an independent risk factor, there were high rates of deep unsensed penetration and aspiration events across all oxygen flow levels. This indicates a high level of vigilance is necessary and prioritizing patient safety is recommended for critically ill patients receiving HFNO.