Research in high flow therapy: mechanisms of action.
Recently, heater/humidifier devices that use novel methods to condition breathing gases from an external source have been introduced. The addition of sufficient warmth and high levels of humidification to breathing gas has allowed for higher flow rates from nasal cannula devices to be applied to patients (i.e., high flow therapy). This article provides a review of the proposed mechanisms behind the efficacy of high flow therapy via nasal cannula, which include washout of nasopharyngeal dead space, attenuation of the inspiratory resistance associated with the nasopharynx, improvement in conductance and pulmonary compliance, mild distending pressure and reduction in energy expenditure for gas conditioning.
Dysart
Kevin
K
Department of Pediatrics, Jefferson Medical College/Thomas Jefferson University, Philadelphia, PA, USA. kdysart@nemours.org
Miller
Thomas L
TL
Wolfson
Marla R
MR
Shaffer
Thomas H
TH
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006361:Heating / Q000295:instrumentation / Q000379:methods; D006801:Humans; D006813:Humidity; D007223:Infant; D007231:Infant, Newborn; D008171:Lung Diseases / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009305:Nasopharynx / Q000503:physiopathology; D010102:Oxygen Inhalation Therapy / Q000295:instrumentation* / Q000379:methods; D012121:Respiration, Artificial / Q000295:instrumentation; D012126:Respiratory Dead Space / Q000502:physiology*; D014939:Work of Breathing / Q000502:physiology; D055815:Young Adult