High-flow nasal cannula oxygen therapy in adults.

Masaji Nishimura

doi:10.1186/s40560-015-0084-5

Abstract

High-flow nasal cannula (HFNC) oxygen therapy comprises an air/oxygen blender, an active humidifier, a single heated circuit, and a nasal cannula. It delivers adequately heated and humidified medical gas at up to 60 L/min of flow and is considered to have a number of physiological effects: reduction of anatomical dead space, PEEP effect, constant fraction of inspired oxygen, and good humidification. While there have been no big randomized clinical trials, it has been gaining attention as an innovative respiratory support for critically ill patients.Most of the available data has been published in the neonatal field. Evidence with critically ill adults are poor; however, physicians apply it to a variety of patients with diverse underlying diseases: hypoxemic respiratory failure, acute exacerbation of chronic obstructive pulmonary disease, post-extubation, pre-intubation oxygenation, sleep apnea, acute heart failure, patients with do-not-intubate order, and so on. Many published reports suggest that HFNC decreases breathing frequency and work of breathing and reduces needs of escalation of respiratory support in patients with diverse underlying diseases.Some important issues remain to be resolved, such as its indication, timing of starting and stopping HFNC, and escalating treatment. Despite these issues, HFNC oxygen therapy is an innovative and effective modality for the early treatment of adults with respiratory failure with diverse underlying diseases.

Highlights

The purpose of respiratory support is to maintain adequate ventilation and oxygenation
We use the term High-flow nasal cannula (HFNC) throughout the text, in which we summarize the physiological effects of HFNC and review the clinical trials
Millar et al have reported the successful use of HFNC oxygen therapy to manage the hypercapnic respiratory failure of a patient unable to tolerate conventional noninvasive ventilation (NIV) [35]

Summary

Introduction

Administration of supplemental oxygen has been the first-line therapy for hypoxemic patients. Millar et al have reported the successful use of HFNC oxygen therapy to manage the hypercapnic respiratory failure of a patient unable to tolerate conventional NIV [35]. From the reported physiological effects of HFNC, high flow through a nasal cannula meets resistance from patient expiration, and pressure in the pharynx increases. Sztrymf et al investigated the effects of HFNC on alleviating respiratory distress and ameliorating oxygenation in adult ICU patients with mild to moderate hypoxemic ARF [8]. In a cardiothoracic ICU, Parke et al evaluated whether HFNC was better tolerated, with fewer treatment failures, than conventional face mask delivery in patients with mild to moderate hypoxemic respiratory failure [17]. Lucangelo et al used HFNC during bronchoscopy in adults and compared the effects of HFNC at 40 and

Respiratory arrest

Findings

Conclusions