Determining the optimum high-flow nasal cannula flow rate to achieve the desired fraction of inspired oxygen: A bench study

Background: Purpose: High-flow nasal cannula (HFNC) has many benefits in various clinical conditions. The original hypothesis suggests that the high and constant fraction of inspired oxygen (FiO2) is one of the main physiological effects. However, increasing evidence shows that there is a gap betwee...

Full description

Saved in:
Bibliographic Details
Main Authors: Chao-Lan Huang, Chun-Ching Lu, Cheng Chiang, Heng-Sheng Chao, Ting-Yun Chiang, Wei-Nung Teng, Wen-Kuei Chang, Chien-Kun Ting
Format: Article
Language:English
Published: Elsevier 2025-08-01
Series:Journal of the Formosan Medical Association
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S0929664624003577
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849408722566119424
author Chao-Lan Huang
Chun-Ching Lu
Cheng Chiang
Heng-Sheng Chao
Ting-Yun Chiang
Wei-Nung Teng
Wen-Kuei Chang
Chien-Kun Ting
author_facet Chao-Lan Huang
Chun-Ching Lu
Cheng Chiang
Heng-Sheng Chao
Ting-Yun Chiang
Wei-Nung Teng
Wen-Kuei Chang
Chien-Kun Ting
author_sort Chao-Lan Huang
collection DOAJ
description Background: Purpose: High-flow nasal cannula (HFNC) has many benefits in various clinical conditions. The original hypothesis suggests that the high and constant fraction of inspired oxygen (FiO2) is one of the main physiological effects. However, increasing evidence shows that there is a gap between the actual FiO2 and administered FiO2. We aimed to determine the actual FiO2 under different respiratory conditions and develop a regression model using a spontaneous breathing lung model. Methods: A spontaneous breathing simulation model was built using an airway manikin and a model lung. The FiO2 was measured under different respiratory conditions with varying tidal volumes and respiratory and HFNC flow rates. The relationships between the respiratory parameters and actual FiO2 were determined and used to build the predictive model. Results: The actual FiO2 was negatively correlated with respiratory rate and tidal volume and positively correlated with HFNC flow. The regression model could not be developed using simple respiratory parameters. Therefore, we introduced a new variable, defined as flow ratio, which equaled the HFNC flow divided by inspiratory flow. Our equation demonstrated that the actual FiO2 was mainly determined by the flow ratio in a non-linear relationship. Accordingly, a flow ratio greater than 1 did not ensure a constant high FiO2, whereas a flow ratio >1.435 could produce FiO2 >0.9. Conclusion: The FiO2 during HFNC was not constant even at sufficiently high oxygen flow compared with inspiratory flow. The predictive model showed that the actual FiO2 was mainly determined by the flow ratio.
format Article
id doaj-art-047d688b2aa84f718526ffb92e52d5a4
institution Kabale University
issn 0929-6646
language English
publishDate 2025-08-01
publisher Elsevier
record_format Article
series Journal of the Formosan Medical Association
spelling doaj-art-047d688b2aa84f718526ffb92e52d5a42025-08-20T03:35:43ZengElsevierJournal of the Formosan Medical Association0929-66462025-08-01124871872310.1016/j.jfma.2024.08.006Determining the optimum high-flow nasal cannula flow rate to achieve the desired fraction of inspired oxygen: A bench studyChao-Lan Huang0Chun-Ching Lu1Cheng Chiang2Heng-Sheng Chao3Ting-Yun Chiang4Wei-Nung Teng5Wen-Kuei Chang6Chien-Kun Ting7Department of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Anesthesiology, School of Medicine, National Yang Ming Chiao Tung University, Taipei, TaiwanDepartment of Orthopedics and Traumatology, National Yang Ming Chiao Tung University Hospital, Yilan, Taiwan; Department of Orthopedics, School of Medicine, National Yang Ming Chiao Tung University, Taipei, TaiwanDepartment of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Anesthesiology, School of Medicine, National Yang Ming Chiao Tung University, Taipei, TaiwanDepartment of Chest Medicine, Taipei Veterans General Hospital, Taipei, TaiwanDepartment of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Anesthesiology, School of Medicine, National Yang Ming Chiao Tung University, Taipei, TaiwanDepartment of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Anesthesiology, School of Medicine, National Yang Ming Chiao Tung University, Taipei, TaiwanDepartment of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Anesthesiology, School of Medicine, National Yang Ming Chiao Tung University, Taipei, TaiwanDepartment of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Anesthesiology, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan; Institute of Emergency and Critical Care Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan; Corresponding author. Department of Anesthesiology, Taipei Veterans General Hospital Institute of Emergency and Critical Care Medicine, National Yang Ming Chiao Tung University, 112, Taipei, Taiwan.Background: Purpose: High-flow nasal cannula (HFNC) has many benefits in various clinical conditions. The original hypothesis suggests that the high and constant fraction of inspired oxygen (FiO2) is one of the main physiological effects. However, increasing evidence shows that there is a gap between the actual FiO2 and administered FiO2. We aimed to determine the actual FiO2 under different respiratory conditions and develop a regression model using a spontaneous breathing lung model. Methods: A spontaneous breathing simulation model was built using an airway manikin and a model lung. The FiO2 was measured under different respiratory conditions with varying tidal volumes and respiratory and HFNC flow rates. The relationships between the respiratory parameters and actual FiO2 were determined and used to build the predictive model. Results: The actual FiO2 was negatively correlated with respiratory rate and tidal volume and positively correlated with HFNC flow. The regression model could not be developed using simple respiratory parameters. Therefore, we introduced a new variable, defined as flow ratio, which equaled the HFNC flow divided by inspiratory flow. Our equation demonstrated that the actual FiO2 was mainly determined by the flow ratio in a non-linear relationship. Accordingly, a flow ratio greater than 1 did not ensure a constant high FiO2, whereas a flow ratio >1.435 could produce FiO2 >0.9. Conclusion: The FiO2 during HFNC was not constant even at sufficiently high oxygen flow compared with inspiratory flow. The predictive model showed that the actual FiO2 was mainly determined by the flow ratio.http://www.sciencedirect.com/science/article/pii/S0929664624003577Anatomic modelsCannulaStatistical modelsOxygen inhalation therapy
spellingShingle Chao-Lan Huang
Chun-Ching Lu
Cheng Chiang
Heng-Sheng Chao
Ting-Yun Chiang
Wei-Nung Teng
Wen-Kuei Chang
Chien-Kun Ting
Determining the optimum high-flow nasal cannula flow rate to achieve the desired fraction of inspired oxygen: A bench study
Journal of the Formosan Medical Association
Anatomic models
Cannula
Statistical models
Oxygen inhalation therapy
title Determining the optimum high-flow nasal cannula flow rate to achieve the desired fraction of inspired oxygen: A bench study
title_full Determining the optimum high-flow nasal cannula flow rate to achieve the desired fraction of inspired oxygen: A bench study
title_fullStr Determining the optimum high-flow nasal cannula flow rate to achieve the desired fraction of inspired oxygen: A bench study
title_full_unstemmed Determining the optimum high-flow nasal cannula flow rate to achieve the desired fraction of inspired oxygen: A bench study
title_short Determining the optimum high-flow nasal cannula flow rate to achieve the desired fraction of inspired oxygen: A bench study
title_sort determining the optimum high flow nasal cannula flow rate to achieve the desired fraction of inspired oxygen a bench study
topic Anatomic models
Cannula
Statistical models
Oxygen inhalation therapy
url http://www.sciencedirect.com/science/article/pii/S0929664624003577
work_keys_str_mv AT chaolanhuang determiningtheoptimumhighflownasalcannulaflowratetoachievethedesiredfractionofinspiredoxygenabenchstudy
AT chunchinglu determiningtheoptimumhighflownasalcannulaflowratetoachievethedesiredfractionofinspiredoxygenabenchstudy
AT chengchiang determiningtheoptimumhighflownasalcannulaflowratetoachievethedesiredfractionofinspiredoxygenabenchstudy
AT hengshengchao determiningtheoptimumhighflownasalcannulaflowratetoachievethedesiredfractionofinspiredoxygenabenchstudy
AT tingyunchiang determiningtheoptimumhighflownasalcannulaflowratetoachievethedesiredfractionofinspiredoxygenabenchstudy
AT weinungteng determiningtheoptimumhighflownasalcannulaflowratetoachievethedesiredfractionofinspiredoxygenabenchstudy
AT wenkueichang determiningtheoptimumhighflownasalcannulaflowratetoachievethedesiredfractionofinspiredoxygenabenchstudy
AT chienkunting determiningtheoptimumhighflownasalcannulaflowratetoachievethedesiredfractionofinspiredoxygenabenchstudy