To: Epistaxis as a complication of high-flow nasal cannula therapy in adults - Critical Care Science (CCS)

To: Epistaxis as a complication of high-flow nasal cannula therapy in adults |

TO THE EDITOR

We have read with great interest this original article by Veiga et al. titled “Epistaxis as a complication of high-flow nasal cannula therapy in adults”.⁽⁾ Although epistaxis is an infrequent complication, it is very interesting as epistaxis has important clinical repercussions. The authors consider that the high flow rate in use (65L/minute) and smaller prong configuration that increases the velocity of the gas represent a jetting effect. Although the authors did not find any difference in risk factors for epistaxis, we propose several factors that should be taken into account.

First, information about the associated mechanism and mucosal tissue of the nasal airways is essential. From a physiological point of view, we do not have information about the impact of mouth breathing prevalence. Mouth breathing is a critical factor for humidity and temperature control at the nasal-mouth level.^(,) We consider that the fundamental mechanism is a loss or ineffectiveness of humidity, which is related to nasal dryness together with the added effects of oxygenation.⁽⁾

[...]