The Impact of High-Flow Nasal Cannula on Olfactory Function

Area of Science:

• Critical Care Medicine
• Pulmonology
• Otolaryngology

Background:

• High-flow nasal cannula (HFNC) therapy enhances respiratory parameters like gas exchange and lung compliance.
• Humid and hyperbaric conditions are known to improve olfactory function compared to dry environments.
• Acute respiratory failure (ARF) can potentially impact sensory functions, including olfaction.

Purpose of the Study:

• To investigate the effect of HFNC oxygen therapy on olfactory function in patients with ARF.
• To compare olfactory function in ARF patients to healthy controls.

Main Methods:

• A prospective, observational study involving 30 ARF patients admitted to the ICU.
• Olfactory sniff tests (odor threshold, discrimination, identification, and total score) were performed before and after HFNC therapy.
• Comparison of olfactory scores between ARF patients and 30 healthy controls.

Main Results:

• ARF patients exhibited significantly lower baseline olfactory function (odor threshold, discrimination, identification, and total score) compared to healthy controls (P < .001).
• HFNC oxygen therapy resulted in significant improvements in odor threshold (P = .02), odor discrimination (P = .001), odor identification (P = .02), and total olfactory score (P < .001) in ARF patients.
• The mean total olfactory score increased from 25.5 ± 3.8 to 27.1 ± 3.5 after HFNC therapy.

Conclusions:

• Patients with ARF demonstrate relative olfactory dysfunction compared to healthy individuals.
• HFNC therapy is effective in improving olfactory function in patients with ARF experiencing hypoxemia.
• This suggests HFNC is a beneficial intervention for managing olfactory deficits in ARF patients.