Combined effects of a nasal dilator and nasal prongs on nasal airflow resistance

STUDY OBJECTIVES: Nasal prongs (NPs), when used to assess nasal flow, can result in dramatic increases in nasal airflow resistance (NR). The aim of this study was to investigate whether the NP-induced increases in NR could be corrected by the simultaneous use of an internal nasal dilator (ND). DESIGN: NR was estimated by posterior rhinomanometry, in the basal state (NRb), and while breathing with NP (NRp), with ND (NRd), and with both ND and NP (NRd + p). PARTICIPANTS: The study was performed in 15 healthy subjects. Measurements and results: NR (mean NRb [+/- SEM], 2.5 +/- 0.4 cm H(2)O/L/s) significantly decreased with ND (NRd = 1.4 +/- 0.2 cm H(2)O/L/s; p < 0.001) and significantly increased with NP (NRp = 3.8 +/- 0.8 cm H(2)O/L/s; p < 0.001). A significant logarithmic relationship was found between NRd and NRb (r(2) = 0.95; p < 0.0001), and a significant exponential relationship was found between NRp and NRb (r(2) = 0.99; p < 0.0001). While breathing with both ND and NP, NRd + p was significantly lower than NRb (1.9 +/- 1.4 cm H(2)O/L/s; p < 0.02). CONCLUSIONS: Our results demonstrate that the ND tends to slightly overcorrect the NP-induced increase in NR and suggest that, in view of the possible effects of NPs on upper airway resistance, the combination of both devices might be used for nasal airflow monitoring during nocturnal polysomnography in patients presenting with highly resistive nares.     

Effects of nasal prongs on nasal airflow resistance

STUDY OBJECTIVES: The aim of this study was to investigate whether nasal prongs, which have been proposed to assess nasal flow during sleep, affect nasal airflow resistance (NR). DESIGN: NR was estimated by posterior rhinomanometry at a 0.5 L/s flow, under eight conditions: in the basal state, and with seven different nasal prongs. PARTICIPANTS: The study was performed in 17 healthy supine subjects, 8 of whom had basal NR values within the normal range (< or = 2 cm H(2)O.L(-1).s, group 1), and 9 had increased basal NR values (> 2.5 cm H(2)O.L(-1).s, group 2), because of nare narrowness and/or deviated nasal septum. Measurements and results: NR increased significantly while breathing with nasal prongs (p < 0.0001 in both groups). The changes in NR (DeltaNR) induced by the different nasal prongs were characterized by large intersubject and intrasubject variability, with a maximum DeltaNR of 24.2 cm H(2)O.L(-1).s. Significant differences were found between the DeltaNR induced by the different nasal prongs (p < 0.001 in group 1, and p < 0.0003 in group 2), and for six of them, DeltaNR was significantly higher in group 1 than in group 2 (p < 0.02). CONCLUSIONS: This study demonstrates that nasal prongs can markedly increase NR in subjects presenting with nare narrowness and/or deviated nasal septum. Further investigations that would include nocturnal polysomnography are still required to evaluate the possible influence of nasal prongs on the diagnosis of obstructive sleep apnea syndrome and its severity.     

经鼻高流量氧疗

经鼻高流量氧疗(high-flow nasal oxygen,HFNO)是一种新型的氧疗技术,近年来开始逐步在临床普及应用。经过临床研究的不断探索,发现HFNO相较于传统氧疗具有诸多优势,并且在部分呼吸衰竭患者中的应用效果与无创通气相似,这为呼吸衰竭患者的呼吸支持提供了新的选择和思路。但其临床具体适应证仍不明确,因此现阶段应重视HFNO的临床使用规范,而其适用范围仍需临床研究的进一步探索。该文就其研究概况进行综述。     

The effect of nasal decongestant on nasal mucous velocity.

Nasal mucous velocity was measured in 13 healthy nonsmokers before and 10 min after topical application of 2 alpha adrenergic nasal decongestant sprays, phenylephrine and tetrahydrozoline. Phenylephrine increased nasal mucous velocity from 8.4 +/- 2.7 mm per min (mean +/- SD) to 13.7 +/- 4.8 mm per min and tetrahydrozoline from 8.1 +/- 3.8 mm per min (mean +/- SD) to 13.8 +/- 5.1 mm per min. These increases were significant (P less than 0.01) when compared to topical application of phenylephrine and tetrahydrozoline vehicles, normal saline, and sham (empty aerosol container).     

The effect of helium on nasal resistance and nasal flows.

Nasal inspiratory resistance and maximal inspiratory nasal flow were measured in 10 normal subjects while they breathed air and while they breathed a mixture of 80% helium and 20% O2. After the less dense helium-O2 mixture, there was a nonsignificant increase in K1 (15 +/- 93%), a 56 +/- 20% decrease in K2 (P less than 0.001), and a 48 +/- 20% increase in maximal inspiratory nasal flow (P less than 0.001). This is consistent with the accepted concept that K1 represents resistance to laminar flow and K2, resistance to nonlaminar flow (turbulent flow and/or flow due to convective acceleration), and that nonlaminar air flow predominates in the nose.     

Posture and nasal patency

Effects of recumbency on nasal patency were determined in adult subjects by a sensitive computer-assisted posterior rhinometric technique. A modified body plethysmograph was employed to measure air flow and to avoid the disadvantages of facial masking and nasal intubation. In healthy subjects, assumption of recumbency decreases total nasal patency minimally. Lateral recumbency decreases it markedly in the ipsilateral nasal cavity, in which resistance to breathing often exceeds 10 cm H2O (1.0 kPa)/L/s. A concomitant increase in patency, which takes place contralaterally (resistance is frequently reduced to less than 3 cm H2O (0.3 kPa)/L/s), diminishes change in total nasal patency. Ipsilateral decrease and reciprocal contralateral increase in patency are induced also by unilateral pressures to trunk and limbs in dorsally recumbent subjects. This posture minimizes hydrostatic differences between sides. The results indicate that reciprocal nasal vascular responses to lateral recumbent postures are caused by pressure-induced reflexes, and these changes take place independent of hydrostatic differences. Effects of recumbency on the patency of abnormal noses and their relevance to breathing disorders of sleep are discussed.     

Endoscopy in nasal myiasis

Nasal myiasis is a common disease in tropical and developing countries.The maggots cause extensive necrosis, sloughing and destruction of intranasal tissue and reach to deep and inaccessible areas of the nose and paranasal sinuses. In such a situation removal of maggots is difficult by manual extraction and several sittings are required. To overcome this problem nasal endoscope is being used for removal of maggots under direct vision. In comparing both methods nasal endoscopic procedure is found to be superior to the manual extraction method for removal of maggots.The maggots located in deep and inaccessible area can be approached more easily by endoscopic procedure.The disease is being controlled in shorter time and in few sittings.Thus quick and complete eradication of myiasis is possible before the maggots cause irreparable damage to the intranasal tissues.     

Toxicology of nasal irritants

The upper airway, including nasal cavities, naso-, oro-, and hypopharynx, is the portal of entry for air pollutants. Upper airway (as well as eye) irritation figures prominently in symptom reporting in so-called problem buildings and with exposure to environmental tobacco smoke. Large particles and water-soluble gases and vapors are likely to have their initial irritant effects in the mucous membranes of the upper airway and eyes, giving warning to the exposed individual to minimize further exposure. The spectrum of irritant-related upper airway health effects is reviewed in this article.     

Snoring is not relieved by nasal surgery despite improvement in nasal resistance

OBJECTIVES: In the present study, we evaluated the effect of nasal surgery on snoring time, snoring intensity, and sleep-disordered breathing. The role of abnormal cephalometry in treatment outcome was assessed. DESIGN: A cross-sectional prospective study. SETTING: University teaching hospital. PATIENTS: Forty consecutive snoring men who were referred to ENT Hospital because of a snoring problem or suspicion of sleep apnea. INTERVENTIONS: The patients underwent anterior rhinomanometry and polysomnography (PSG) with recording of snoring before and after operative treatment of nasal obstruction. Cephalometric radiographs were obtained before surgery. RESULTS: Nasal resistance decreased significantly in the overall patient group. Snoring time, snoring intensity, nocturnal breathing, and sleep architecture did not change after nasal surgery. Cephalometry did not predict operative outcome in these patients. Snoring intensity was found to be significantly higher during non-rapid eye movement (NREM) sleep than during rapid eye movement sleep. CONCLUSIONS: Operative treatment of mainly structural nasal obstruction did not seem to decrease snoring intensity, snoring time, or sleep-disordered breathing in an objective assessment by PSG performed after surgery. The effect of treating inflammatory nasal changes during nocturnal breathing, as well as the role of cephalometry in the prediction of treatment outcome will need further evaluation. Higher snoring intensity related to NREM sleep may add to the sleep disturbance of a bed partner in the evening.     

Mediators in nasal polyposis

Nasal polyposis (NP) is a chronic inflammatory disease of the sinuses often associated with asthma. Although we have not yet achieved a full understanding of the precise mechanisms underlying the pathogenesis of NP, recent insights have been acquired into the regulation of eosinophil chemotaxis, activation, and survival, in addition to their possible link to gross histopathologic changes such as pseudocyst formation. Interleukin (IL)-5, transforming growth factor-β1, and eotaxin seem to be crucial players in the regulation of eosinophilic inflammation and extracellular matrix breakdown. The cytokine pattern in NP assumes neither a T helper 1 (Th1) nor Th2 type predominance, because IL-4, IL-5, IL-12, and interferon-γ have all been shown to be upregulated in NP tissue, without influence of the atopic status. However, recent studies have demonstrated a strong local upregulation of the immunoglobulin E (IgE) synthesis with the formation of specific IgE to Staphylococcus aureus enterotoxins, suggesting a possible role of superantigens in these pathologic processes.     

Mycotic bovine nasal granuloma

A case of mycotic bovine nasal granuloma in a 10 year-old Jersey cow, produced by Drechslera halodes is presented. Histopathological sections showed abundant hyaline and pigmented extra and intracellular fungal structures together with a polymorphic cellular granuloma formed by neutrophils, lymphocytes, plasmocytes, histiocytes and giant cells of the Langhans type. It is the first case of mycotic bovine nasal granuloma recognized in Uruguay although this disease seems to be frequent according to the opinion of veterinarian specialists. Another similar clinical case also in a Jersey cow from the same dairy house with an intense cellular infiltrate rich in eosinophils without granulomatous image, together with extracellular hyaline and fuliginous fungal forms, is also referred for comparative purposes. Geotrichum sp. was isolated. The need of an early diagnosis and treatment of the disease is stressed.