BACKGROUND: Nasal high-flow oxygen therapy increases the mean nasopharyngeal airway pressure in adults, but the relationship between flow and pressure is not well defined. OBJECTIVE: To determine the relationship between flow and pressure with the Optiflow nasal high-flow oxygen therapy system. METHODS: We invited patients scheduled for elective cardiac surgery to participate. Measurements were performed with nasal high-flow oxygen at flows of 30, 40, and 50 L/min, with the patient's mouth both open and closed. Pressures were recorded over one minute of breathing, and average flows were calculated via simple averaging. RESULTS: With the mouth closed, the mean ± SD airway pressures at 30, 40, and 50 L/min were 1.93 ± 1.25 cm H(2)O, 2.58 ± 1.54 cm H(2)O, and 3.31 ± 1.05 cm H(2)O, respectively. There was a positive linear relationship between flow and pressure. CONCLUSIONS: The mean nasopharyngeal pressure during nasal high-flow oxygen increases as flow increases. Australian Clinical Trials Registry http://www.adhb.govt.nz/achicu/hot_2_airway_pressure.htm.
BACKGROUND: Nasal high-flow oxygen therapy increases the mean nasopharyngeal airway pressure in adults, but the relationship between flow and pressure is not well defined. OBJECTIVE: To determine the relationship between flow and pressure with the Optiflow nasal high-flow oxygen therapy system. METHODS: We invited patients scheduled for elective cardiac surgery to participate. Measurements were performed with nasal high-flow oxygen at flows of 30, 40, and 50 L/min, with the patient's mouth both open and closed. Pressures were recorded over one minute of breathing, and average flows were calculated via simple averaging. RESULTS: With the mouth closed, the mean ± SD airway pressures at 30, 40, and 50 L/min were 1.93 ± 1.25 cm H(2)O, 2.58 ± 1.54 cm H(2)O, and 3.31 ± 1.05 cm H(2)O, respectively. There was a positive linear relationship between flow and pressure. CONCLUSIONS: The mean nasopharyngeal pressure during nasal high-flow oxygen increases as flow increases. Australian Clinical Trials Registry http://www.adhb.govt.nz/achicu/hot_2_airway_pressure.htm.
Authors: Amanda Corley; Melannie Edwards; Amy J Spooner; Kimble R Dunster; Chris Anstey; John F Fraser Journal: Intensive Care Med Date: 2016-11-30 Impact factor: 17.440
Authors: Bernd E Winkler; Ralf M Muellenbach; Thomas Wurmb; Manuel F Struck; Norbert Roewer; Peter Kranke Journal: J Clin Monit Comput Date: 2016-02-09 Impact factor: 2.502
Authors: Amanda Corley; Taressa Bull; Amy J Spooner; Adrian G Barnett; John F Fraser Journal: Intensive Care Med Date: 2015-04-08 Impact factor: 17.440