Advances about application of high-flow nasal cannula oxygen therapy for adult emergency patients / 中国中西医结合急救杂志

ABSTRACT

Conventional oxygen therapy (COT) is generally provided through a low flow rate device including a nasal cannula or facemask. Since the benefits of high-flow nasal cannula (HFNC) oxygen therapy in adults with acute respiratory failure (ARF) have firstly been demonstrated by Roca et al and because of its effectivity and comfort and good compliance, it has shown greater advantageous than COT and it has been increasingly used in adults with mild to moderate ARF and obtained very nice therapeutic effect. However, because of the specificity of emergency environment and the more complexity of HFNC system than COT, the use of HFNC in department of emergency is still controversial. Since HFNC system delivers oxygen by high-flow rate, the dilution of inspired oxygen concentration (FiO2) by room air can be maximally decreased, and the system can provide the highest flow rate up to 60 L/min, being greater than the patients' peak inspiration flow flow (PIF); the high flow rate can dilute the carbon dioxide (CO2) concentration in the anatomical dead space, and the above several factors can guarantee that HFNC may deliver 0.21-1.00 relatively constant FiO2. Therefore, HFNC as a new noninvasive supplemental oxygen therapy has been increasingly widely studied and used in the adult patients with ARF. In this article, we will review the HFNC physiological effects and its advances in application for adult patients in department of emergency.