Characteristics of Flow Author Interview
Below is an interview with first author, Robert Kacinski, and senior author, Scott Leonard, on a paper that they presented at the 8th Thermal and Fluids Engineering Conference (TFEC) in May 2023 comparing flow characteristics in the upper airway with 1. no therapy, 2. high flow nasal cannula (HFNC) therapy and 3. high velocity nasal insufflation (HVNI) in different scenarios.
Specifically, they were trying to understand the ability of the HFNC and HVNI to reduce the levels of CO2 at the end of exhalation, which should be minimized for recovery of patients in respiratory distress. The authors modeled open and closed mouth models and found that HVNI more effectively reduced the upper airway of CO2 by the end of exhalation than HFNC for all scenarios. The difference was most pronounced in the open mouth model in which CO2 at end of exhalation for HVNI was less than half than that for HFNC.
To skip to specific areas of interest, there are time stamps of the areas of discussion under the video.
| Time | Areas Covered |
| 0:00 – 0:34 | Author introduction |
| 0:35 – 2:23 | Study objectives |
| 2:24 – 4:04 | Study Results |
| 4:05 – 5:09 | Result Explanations |
| 5:10 – 7:16 | Rationale for Use of Computational Fluid Dynamics (CFD) Model |
| 7:17 – 9:07 | CFD Model Advantages and Disadvantages |
| 9:08 – 10:25 | How well does CFD model the airway |
| 10:26 – 12:16 | How well does CFD model breathing |
| 12:17 – 18:09 | CFD Model Set-up |
| 18:10 – 20:10 | CO2 Measure Point |
| 20:11 – 28:06 | Review of CFD Modeling Graphics – HFNC vs HVNI 1 (ProSoft) – 24:53 -27:03 – HFNC vs HVNI 2 (Standard Cannula) – 27:04 – 28:06 |
| 28:07 – 33:13 | Review of Open and Closed Mouth Graph – Open Mount Graph – 28:07 – 30:47 – Closed Mouth Graph – 30:48 31:46 – Comparison of two – 31:47 – 33:13 |
| 33:14 – 36:16 | Review of Velocity Magnitude Graphic |
| 36:17 – 37:54 | Review of Turbulent Kinetic Energy Graphic |
| 37:54 – 39:28 | Clinical Implications of the Study |