Jian-Qiao Xu1, Long-Xiang Su2, Peng Yan1, Xing-Shuo Hu1, Ruo-Xuan Wen1, Kun Xiao1, Hong-Jun Gu1, Jin-Gen Xia3, Bing Sun4, Qing-Tao Zhou5, Yu-Chao Dong6, Jia-Lin Liu7, Pin-Hua Pan8, Hong Luo9, Qi Li10, Li-Qiang Song11, Si-Cheng Xu12, Yan-Ming Li13, Dao-Xin Wang14, Dan Li15, Qing-Yuan Zhan3, Li-Xin Xie1. 1. Department of Pulmonary & Critical Care Medicine, Chinese People Liberation Army (PLA) General Hospital, Beijing 100853, China. 2. Department of Critical Care Medicine, Peking Union Medical College Hospital, Beijing 100005, China. 3. Department of Pulmonary & Critical Care Medicine, China and Japan Friendship Hospital, Beijing 100029, China. 4. Department of Pulmonary & Critical Care Medicine, Beijing Chaoyang Hospital affiliated to Capital Medical University, Beijing 100020, China. 5. Department of Pulmonary & Critical Care Medicine, Peking University Third Hospital, Beijing 100191, China. 6. Department of Respiratory Medicine, Changhai Hospital, Shanghai 200433, China. 7. Department of Respiratory Medicine, Ruijin Hospital Affiliated to the Shanghai Jiao Tong University Medical School, Shanghai 200025, China. 8. Department of Respiratory Medicine, XiangYa Hospital, Central South University, Changsha, Hunan 410008, China. 9. Department of Pulmonary & Critical Care Medicine, XiangYa Second Hospital of Central South University, Changsha, Hunan 410011, China. 10. Department of Pulmonary & Critical Care Medicine, Xinqiao Hospital of the Third Military Medical University, Chongqing 400037, China. 11. Department of Pulmonary & Critical Care Medicine, Xijing Hospital of Fourth Military Medical University, Xi'an, Shaanxi 710032, China. 12. Department of Respiratory Medicine, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830000, China. 13. Department of Pulmonary & Critical Care Medicine, Beijing Hospital, Beijing 100730, China. 14. Department of Respiratory Medicine, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China. 15. Department of Respiratory Medicine, The First Bethune Hospital of Jilin University, Changchun, Jilin 130021, China.
High-flow nasal cannula oxygen therapy (HFNC) is a novel respiratory support technology and has been extensively applied in clinics in recent years. This therapeutic equipment mainly includes an air-oxygen blender, an active humidifier, a high-flow nasal cannula, and a connecting inspiratory circuit. It provides patients a humidified high-flow gas (8–80 L/min) with relatively stable oxygen concentration (21–100%), temperature (31–37°C) and performs oxygen therapy via a nasal cannula, which is very comfortable.[ Through inspiration of high-flow gases, HFNC can produce a certain level of positive end-expiratory pressure[ and wash the biological dead space of the upper respiratory tract.[ Gases with constant temperature and humidity provided through a high-flow nasal cannula can maintain the function of the mucociliary clearance system[ and reduce upper airway resistance and breathing effort of patients to improve gas exchange and partial ventilation functions.The Pulmonary & Critical Care Medicine Group of Chinese Thoracic Society, Pulmonary & Critical Care Medicine Committee of Chinese Association of Chest Physicians, took the lead in writing an Expert Consensus on Clinical Standardized Application of HFNC Oxygen therapy in Adults, with the goal of Standardizing the clinical application of HFNC in China [Supplementary Digital content]. The standard of evidence levels were as follows: level I: high-quality randomized controlled trials (RCT), authoritative guidelines, and high-quality systemic reviews and meta-analyses; level II: RCTs with a certain study limitation (such as unconcealed grouping, no blind method, and failure to report loss to follow-up), cohort studies, case-series studies and case-controlled studies; and level III: case report and expert opinions.[ We have extracted the following aspects to present our viewpoints.The application timing, indications, and contraindications for HFNC are shown in Table 1.
Table 1
Indications and contraindications for the clinical application of HFNC.
For clinical application, this consensus has resulted in a flowchart for the clinical application timing of HFNC [Figures 1 and 2].
Figure 1
Application timing of HFNC for acute respiratory failure. PaO2: Partial pressure of oxygen; FiO2: Fraction of inspired oxygen; IPPV: Intermittent positive pressureventilation; HFNC: High-flow nasal cannula oxygen therapy; NPPV: Non-invasive positive pressure ventilation.
Figure 2
Application timing of HFNC after extubation. Criteria for low risk of reintubation in the intensive care unit (ICU) (meet all following criteria): age <65 years; acute physiology and chronic health evaluation score II (APACHE II) < 12 points; body mass index (BMI) <30 kg/m2; patent airway; full expectoration; successfully weaning; number of complication ≤1; without heart failure, moderate-severe chronic obstructive pulmonary disease (COPD) and long-term mechanic ventilation.[ Criteria for high risk of reintubation in the ICU (meet at least 1 of the following criteria): age ≥65 years; heart failure; APACHE II ≥ 12 points; BMI ≥30 kg/m2; expectoration weakness or substantial discharge; at least one spontaneous breathing trial failure; number of complication >1; and invasive mechanic ventilation >7 days.[ HFNC: High-flow nasal cannula oxygen therapy; ICU: Intensive care unit; IPPV: Intermittent positive pressure ventilation; NPPV: Non-invasive positive pressure ventilation.
Indications and contraindications for the clinical application of HFNC.Application timing of HFNC for acute respiratory failure. PaO2: Partial pressure of oxygen; FiO2: Fraction of inspired oxygen; IPPV: Intermittent positive pressureventilation; HFNC: High-flow nasal cannula oxygen therapy; NPPV: Non-invasive positive pressure ventilation.Application timing of HFNC after extubation. Criteria for low risk of reintubation in the intensive care unit (ICU) (meet all following criteria): age <65 years; acute physiology and chronic health evaluation score II (APACHE II) < 12 points; body mass index (BMI) <30 kg/m2; patent airway; full expectoration; successfully weaning; number of complication ≤1; without heart failure, moderate-severe chronic obstructive pulmonary disease (COPD) and long-term mechanic ventilation.[ Criteria for high risk of reintubation in the ICU (meet at least 1 of the following criteria): age ≥65 years; heart failure; APACHE II ≥ 12 points; BMI ≥30 kg/m2; expectoration weakness or substantial discharge; at least one spontaneous breathing trial failure; number of complication >1; and invasive mechanic ventilation >7 days.[ HFNC: High-flow nasal cannula oxygen therapy; ICU: Intensive care unit; IPPV: Intermittent positive pressure ventilation; NPPV: Non-invasive positive pressure ventilation.
Funding
Funding was provided by the China National Key Research Program (2016YFC1304300, 2018ZX09201013) and the China National Clinical Center Program for Geriatric Diseases (NCRCG-PLAGH-2017003).
Figure 1
Figure 2