Electronic cigarettes have been a popular alternative to tobacco smoking. The effect of tobacco smoking on nasal airway resistance has been investigated before; however, the effect of the aerosol generated by electronic cigarettes is still unknown. This study aimed to evaluate the short-term effects of e-cigarettes on nasal airway resistance.

Sixty-one participants were recruited into a vapers group and a control group. The vapers group was instructed to smoke for 5 minutes, and their nasal resistance was measured pre-procedure and at 1 and 5 minutes post-procedure. The results were compared between both groups.

Repeated measures analysis of variance demonstrated that vaping has no statistically significant effect on total nasal airway resistance.

Although the differences between both groups were not statistically significant overall, the vapers group showed a reduction in nasal airway resistance in the short term.

In order to achieve a faster and more reliable anterior rhinomanometric evaluation, nasal skin was prepared using benzoin tincture solution, which provides simpler and better adhesion of the foam tape to the nasal skin.

Two consecutive anterior rhinomanometry measurements were made, one with and one without benzoin tincture application.

The average time taken to perform classic foam tape anterior rhinomanometry without benzoin tincture application was 281.32 seconds, and the average coefficients of variation for the right and left passages were 7.48 and 7.59 per cent, respectively. When benzoin tincture was used, the average time taken for completion of the tests was 121.24 seconds, and the average coefficients of variation for the right and left passages were 2.17 and 2.32 per cent.

The use of benzoin tincture to clean the nasal skin before placing foam tape shortens the procedure duration and significantly increases test reliability.

Left- or right-handedness is a common human trait, and it has been previously reported that human nasal airflow dominance correlates with hand dominance. Any relationship between hand dominance and nasal airflow dominance would be unusual. This study aimed to measure nasal airflow and look for any relationship to handedness.

The modified Glatzel mirror was used to record the dominant nasal passage at 15-minute intervals over a 6-hour period in 29 healthy participants consisting of 15 left-handers and 14 right-handers.

In left-handers, the percentage of time that the left nasal passage was dominant ranged from 0 to 100 per cent. In right-handers, the percentage of time that the right nasal passage was dominant ranged from 4.2 to 95.8 per cent. No correlation between nasal airflow dominance and hand dominance was identified.

The results do not support the hypothesis that nasal airflow and handedness are related.

Over the past few decades, evidence has emerged suggesting that nasal airflow asymmetry and brain asymmetry are linked. The nose exhibits asymmetrical airflow, with the dominant airflow alternating from one nasal passage to the other over a period of hours. Some authors have suggested a correlation between cerebral hemisphere dominance and nostril dominance. Others have proposed an association between rhythmic fluctuations in nasal airflow and corresponding fluctuations in cerebral hemisphere activity. Based on ancient yoga breathing techniques, newer evidence suggests that altering nasal airflow can influence brain activity, with reports of improved cognitive function caused by unilateral forced nostril breathing. It seems that a nasal airflow stimulus may have an activating effect on the brain, as it has also been shown to trigger seizure activity in epileptic patients.

This article explores these theories in detail, reviews the evidence, and presents new models linking nasal airflow and brain activity.

Nasal dilator strips are thought to widen and stiffen the anterior nasal cavity, and thus improve symptoms of nasal obstruction. It is postulated that anthropomorphic differences in external nasal proportions between races may influence the effectiveness of such dilator strips.

Caucasian and Asian subjects were compared. Nasal peak inspiratory flow, nasal airway resistance, minimum cross-sectional area and visual analogue scale measurements of nasal obstruction were recorded at baseline and following the application of two different dilator strips.

Nine Caucasian and six Asian subjects were recruited (n = 15). There was a significant difference between races in terms of nasal peak inspiratory flow improvements following nasal strip application (mean of 29.4 litres per minute in Caucasians vs 14.6 litres per minute in Asians; p = 0.04). Only Caucasians experienced a significant decrease in nasal airway resistance (median of 0.12 Pa/cm3/s; p < 0.01).

Nasal peak inspiratory flow, minimum cross-sectional area and visual analogue scale values improved from baseline with strip application in both populations. Only Caucasians experienced significant nasal airway resistance improvement with strip application. Both cohorts experienced nasal peak inspiratory flow improvement, with Caucasians experiencing a significantly larger improvement.

The alpha-2 adrenergic agonists clonidine and dexmedetomidine are used as an antihypertensive and a sedative, respectively. The aim of this study was to determine the effects of these agonists on ovalbumin-sensitized airway tone in guinea pigs.

The animals were divided into two groups: control and sensitized. The sensitized group received ovalbumin intraperitoneally and was boosted by exposure to aerosolized ovalbumin. The effects of the alpha-2 agonists were investigated by measuring (1) total lung resistance and (2) smooth muscle tension using a tracheal ring preparation.

In the control group, acetylcholine significantly increased total lung resistance in a dose-dependent manner. In the sensitized animals, total lung resistance was significantly higher (by 95%) at 6 μg kg−1 acetylcholine than that in the control group. Both clonidine and dexmedetomidine had a slight but significant inhibitory effect on the response curve of lung resistance at higher concentrations of carbachol, a potent muscarinic receptor agonist. Similar to the data obtained in the control group, both clonidine and dexmedetomidine significantly decreased total lung resistance and the inhibitory effects of these alpha-2 agonists on lung resistance were significantly distinguishable. Similar direct inhibitory effects of the alpha-2 agonists on carbachol-induced muscle contraction were observed in both the control and sensitized groups, the inhibitory effects in the sensitized group being significantly greater.

Both clonidine and dexmedetomidine can relax the airway even in the hyper-reactive state.