title: The effects of gas humidification with high-flow nasal cannula on cultured human airway epithelial cells.
abstract: Humidification of inspired gas is important for patients receiving respiratory support. High-flow nasal cannula (HFNC) effectively provides temperature and humidity-controlled gas to the airway. We hypothesized that various levels of gas humidification would have differential effects on airway epithelial monolayers. Calu-3 monolayers were placed in environmental chambers at 37°C with relative humidity (RH) < 20% (dry), 69% (noninterventional comparator), and >90% (HFNC) for 4 and 8 hours with 10 L/min of room air. At 4 and 8 hours, cell viability and transepithelial resistance measurements were performed, apical surface fluid was collected and assayed for indices of cell inflammation and function, and cells were harvested for histology (n = 6/condition). Transepithelial resistance and cell viability decreased over time (P < 0.001) between HFNC and dry groups (P < 0.001). Total protein secretion increased at 8 hours in the dry group (P < 0.001). Secretion of interleukin (IL)-6 and IL-8 in the dry group was greater than the other groups at 8 hours (P < 0.001). Histological analysis showed increasing injury over time for the dry group. These data demonstrate that exposure to low humidity results in reduced epithelial cell function and increased inflammation.
authors.affiliation: Nemours Biomedical Research, Nemours Research Lung Center, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Road, Wilmington, DE 19803, USA ; Department of Pediatrics, Jefferson Medical College, Thomas Jefferson University, 1025 Walnut Street, Suite 700, Philadelphia, PA 19107, USA ; Department of Pediatrics, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Road, Wilmington, DE 19803, USA.
authors.forename: Aaron
authors.initials: A
authors.lastname: Chidekel
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhu
authors.forename: Jordan
authors.initials: J
authors.lastname: Wang
authors.forename: John J
authors.initials: JJ
authors.lastname: Mosko
authors.forename: Elena
authors.initials: E
authors.lastname: Rodriguez
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Shaffer