LAUSR

Abstract Most nitric oxide research has been related to diagnostic use and exhaled nitric oxide is now commonly used as an early indicator of respiratory disorders such as Kartageners Syndrome, Primary Ciliary Disorder, Cystic Fibrosis, and Asthma. In contrast, inhaled nitric oxide has received very little attention despite the benefits it provides in improving blood oxygenation and flow. The main production sites of inhaled nitric oxide are the nasal cavity and paranasal sinuses. Maxillary sinuses are considered a major contributor to inhaled nasal nitric oxide but there is a lack of knowledge and considerable debate as to how entrainment of this gas occurs. This review article discusses the benefits of inhaled nitric oxide and how nasal physiology could influence nasal nitric oxide entrainment. This review also demonstrates use of computer modelling as a more convenient means to predict inhaled nasal nitric oxide concentrations also discussing a significant disparity between in-vivo physiological and model nasal nitric oxide concentrations. It also proposes how current models could be improved to enable better prediction of in-vivo inhaled nasal nitric oxide concentration levels.