General Medical Information

Nasal Vascular Reflexes

Thomas V. Mccaffrey

Additional physiologic reflexes affecting the nasal vessels have been studied. Because the nose is a part of the respiratory tract, it would be expected that the nasal airway would participate in respiratory reflexes. The phenomenon of nasal decongestion occurring with hypercapnia has been studied in humans and animals. The reflex reduction in nasal resistance that occurs with hypercapnia and hypoxia is mediated by the sympathetic nervous system. The reduction in nasal resistance closely follows the increased ventilation that occurs with these stimuli. Exercise, another known stimulator of ventilation, also has an effect on nasal resistance. Nasal decongestion occurs promptly with the beginning of exercise and is proportional to the increase in ventilation that occurs with the exercise.