Alae nasi activation and nasal resistance in healthy subjects

Abstract

To investigate the effect of alae nasi (AN) activation on nasal resistance, we monitored AN electromyographic (EMG) activity in 17 healthy subjects using surface electrodes placed on either side of the external nares and measured inspiratory nasal resistance utilizing the method of posterior rhinometry. With CO2 inhalation (6 subj), AN EMG activity increased as nasal resistance fell 23 +/- 5% (P less than 0.01). In the same subjects, voluntary flaring of the external nares also increased AN EMG and decreased nasal resistance by 29 +/- 5% (P less than 0.01). Nasal resistance was altered by nasal flaring and CO2 inhalation even after administration of a topical nasal vasoconstrictive spray (8 subj). In six subjects, voluntary nasal flaring or inhibition with the mouth closed produced a 21 +/- 12% change (P less than 0.01) in total airway resistance as measured by body plethysmography. We conclude that activation of the alae nasi will decrease nasal and total airway resistance during voluntary nasal flaring and during CO2 inhalation and thus should be considered in any studies of upper airway resistance.

Effects of hypercapnia and hypoxia on nasal vasculature and airflow resistance in the anaesthetized dog.

“…This suggests that the decrease in nasal airway resistance may not be related to the decrease in blood flow. Some workers suggest that the hypercapnic nasal airway response is due to alae nasi activation by carbon dioxide (Strohl et al 1982). Our finding that the hypercapnic nasal airway response is similar in dogs which breathed spontaneously or under muscular paralysis and controlled ventilation indicates that alae nasi activation is not the major factor accounting for the decrease in airway resistance during hypercapnia.…”

“…Carbon dioxide inhalation causes an 270 HYPERCAPNIA AND HYPOXIA ON NASAL VASCULATURE increase in the nasal alae electromyographic activity (Strohl, O'Cain & Slutsky, 1982). In order to take this variable of alae nasi activation into account, the present study was carried out in both spontaneously breathing and paralysed ventilated animals.…”

Electromyographic responses of a nasal muscle to stimulation of the nasal vestibule in the cat.

“…However, alterations in respiratory resistance would be accompanied by changes in both endexpired CO2 tension and lung volume, both of which are known to influence nasal e.m.g. activity (Strohl et al 1982;Strohl, 1985;Strohl & Fouke, 1985). Thus either or both of these factors may have contributed to the induction of nasal e.m.g.…”

“…In man the phasic contraction of the dilator naris muscle is reported to lower nasal resistance and prevent collapse of the alar wing of the vestibule during inspiration (Strohl, O'Cain & Slutsky, 1982;Haight & Cole, 1983).…”

Válvula nasal: anatomia e fisiologia

“…The nasal muscles -nasal dilator muscle, nasal apex muscle, nasal muscle (wing part) and septum depressor muscleaccording to the anatomical description (Chart 1) 26 , have a dilatory function by voluntary contraction of the nostril and the nasal vestibule to increase air flow and in facial expression. Some authors 27,28 state that there are mild involuntary contractions of these muscles, perceivable by electromyography during breathing, thus facilitating airflow, and also a passive movement caused by airflow itself. Individuals with NV obstruction caused by septum deviation and/or hypertrophy of the inferior turbinate head presented a greater electrical activity of the nasal muscles before corrective surgery 29 ; a greater nasal muscle tone avoids cartilage collapse.…”