Nasal Airway Resistance Computer

An analogue computing system for the measurement of nasal airway resistance (R_n) has been developed. The instrument operates on the principle of measuring the transnasal pressure required to generate a measured nasal airflow rate. The system computes and displays inspiratory or expiratory nasal airway resistance measured at a preselected flow rate. The values are updated on a breath-by-breath basis and presented to a multi-channel recorder and a digital panel meter for visualization. The continuous R_n (at all inspiratory and expiratory flow rates above zero) can also be recorded. Use of the instrument for the evaluation of nasal decongestants has been demonstrated.     

鼻中隔成形术对鼻气道阻力的影响

目的 观察鼻中隔成形术对鼻气道阻力的影响. 方法 应用主动性前鼻测压法,测定51例鼻中隔偏曲患者,行鼻中隔成形术前后鼻气道阻力和主观鼻开放感觉评分情况.结果 51例患者术前鼻气道阻力是(0.666±0.21)KPa/(s·L);术后3个月为(0.302±0.16)KPa/(s·L),12个月为(0.397+0.24)KPa/(s.L);术后3个月和12个月分别与术前比较,差异有统计学意义(均P＜0.01).术前主观鼻开放感觉评分为7.5±1.5,术后3个月为2.0+2.0,10个月为3.0+2.5,术后3个月和12个月分别与术前比较,差异亦有统计学意义(均P＜0.01). 结论 鼻中隔成形术可显著性地降低患者的鼻气道阻力,同时可明显地改善患者的主观鼻开放感觉.     

Nasopharyngeal Symptoms and Nasal Continuous Positive Airway Pressure Therapy in Obstructive Sleep Apnoea Syndrome

Nasal problems are often reported during the treatment of obstructive sleep apnoea syndrome (OSAS) with nasal continuous positive airway pressure (nCPAP) and may jeopardize the use of nCPAP. This retrospective study evaluated the frequency of nasopharyngeal symptoms in OSAS patients before and during nCPAP treatment. A questionnaire was sent to all patients (n=194) with OSAS for whom nCPAP had been prescribed during the years 1990-1995 at the authors' hospital, enquiring about nasopharyngeal symptoms both before and during treatment and nCPAP use. The study population consisted of the 151 patients [128 men and 23 women, median (range) age 54 (31-76) years and body-mass index 34 (17-54) kg/m²] who responded to the questionnaire. Seventy-one percent of patients were still using nCPAP after a median treatment duration of 30 months. The most commonly reported nasopharyngeal symptoms were nasal stuffiness, which was reported by 46% of patients before nCPAP and by 37% during nCPAP, dry nose (39% before and 46% during nCPAP), sneezing (36% and 35%) and rhinorrhoea (21% and 27%). The frequency of nasopharyngeal symptoms did not change with nCPAP treatment. The frequency of nasopharyngeal symptoms before and during nCPAP treatment was similar in those patients who discontinued the treatment (n=44, 29%) compared with those who continued with nCPAP (n=107, 71%). Skin problems caused by the mask (50%), airleak from mouth (44%), difficulty in exhaling (29%) and a sensation of suffocation (26%) were also problems associated with nCPAP treatment. Nasopharyngeal symptoms were common in patients with OSAS before nCPAP was started. There was no significant change in the frequency of these symptoms during nCPAP treatment. Nasopharyngeal symptoms did not seem to affect treatment continuation.     

Changes of Alpha1-Antitrypsin Levels in Allergen-induced Nasal Inflammation

Objectives

Alpha1-antitrypsin (AAT) is the main inhibitor of human neutrophil elastase, and plays a role in counteracting the tissue damage caused by elastase in local inflammatory conditions. The study evaluated the involvement of AAT in nasal allergic inflammation.

Methods

Forty subjects with mono-sensitization to Dermatophagoides pteronyssinus (Dpt) were enrolled. Twenty allergic rhinitis patients frequently complained of nasal symptoms such as rhinorrhea, stuffiness, sneezing, and showed positive responses to the nasal provocation test (NPT) with Dpt (Group I). The other 20 asymptomatic patients showed sensitization to Dpt but negative NPT (Group II). The levels of AAT, eosinophil cationic protein (ECP), and Dpt-specific IgA antibodies were measured in the nasal lavage fluids (NLFs), collected at baseline, 10 minutes, 30 minutes, 3 hours, and 6 hours after the NPT. Nasal mucosa AAT expression was evaluated with immunohistochemical staining from Group I and Group II.

Results

At baseline, only the Dpt-specific IgA level was significantly increased in the NLFs of Group I compared with Group II, while ECP and AAT levels were not significantly different between two groups. After Dpt provocation, AAT, ECP, and Dpt-specific IgA levels were significantly increased in the NLFs of Group I during the early and late responses. The protein expression level of AAT was mostly found in the infiltrating inflammatory cells of the nasal mucosa, which was significantly increased in Group I compared to Group II.

Conclusion

The increment of AAT showed a close relationship with the activation of eosinophils induced by allergen-specific IgA in the NLFs of patients with allergic rhinitis after allergen stimulation. These findings implicate AAT in allergen-induced nasal inflammation.     

Experimental Nasal Intubation: A Study of Changes in Nasoantral Mucosa and Bacterial Flora

Objectives: To investigate the local effects in a nasal cavity and its adjacent sinuses of long-term detention of an endonasal tube, with special attention to inflammatory pathology and microbiology. Study Design: Experimental rabbit study. Methods: Four groups of 4 rabbits, in all 16, were unilaterally nasally intubated and evaluated macroscopically, histopathologically, and bacteriologically after 1, 2, 4, and 8 weeks, respectively. Results: At first, in the 1- and 2-week groups to the 4-week group, histopathology, such as degeneration of olfactory mucosa, squamous cell metaplasia, and polyp formations, was observed together with frequent opportunistic bacterial findings in the nasal cavity. Later, in the 4- and 8-week groups, inflammatory mucosal changes, such as septal increase of connective tissue, goblet cell hyperplasia, and epithelial invaginations, were found in the nasal cavity containing a tube. A concomitant increase was found of commensal bacteria adjacent to the tube and the similar bacterial findings in the ipsilateral maxillary sinuses. However, there were no signs of inflammatory reactions in the sinuses. Conclusions: Our investigation points to the tube as the cause of local goblet cell hyperplasia with an increased mucus production, and as a food source for the commensals with a marked increase of the amount of bacteria. The positive bacterial cultures from the maxillary sinuses might be considered to be colonization. However, because of the possibility of contamination, improved sampling techniques are required, as are further studies.     

Role of Vascular Reflex in Nasal Mucosal Swelling in Nasal Allergy

Objective: In patients with nasal allergy, antigen challenge on the unilateral nasal mucosa results in nasal secretion not only in the ipsilateral but also in the contralateral nasal cavities that can be inhibited almost completely by premedication with atropine sulfate. The present study was performed to elucidate if centrally mediated vascular reflex induced by antigen challenge plays a role in nasal mucosal swelling in subjects with nasal allergy. Methods: Variations of mucosal swelling and mucosal blood flow in the ipsilateral and the contralateral nasal cavities after unilateral antigen challenge were evaluated by acoustic rhinometry and laser Doppler flowmetry in 20 patients with perennial nasal allergy. Results: Unilateral antigen challenge caused ipsilateral and contralateral nasal mucosal swelling in 17 and 13 patients, respectively. Incidence of contralateral nasal mucosal swelling after unilateral antigen challenge was significantly higher compared with that after control disc challenge (P < .001). In 10 patients in whom unilateral antigen challenge caused bilateral nasal mucosal swelling, significant swelling of the nasal mucosa lasted for more than 30 minutes in the ipsilateral nasal cavity after antigen challenge compared with only 15 minutes in the contralateral nasal cavity. Peak values of contralateral mucosal swelling were 45.3% of those of ipsilateral nasal mucosa. Conclusions: Centrally mediated vascular reflex is partially involved in the onset of nasal mucosal swelling observed after antigen challenge in subjects with nasal allergy. However, nasal mucosal swelling that persists and proceeds even 20 minutes after antigen challenge is caused by the direct effects of chemical mediators on the nasal vasculature.