			Home About us Contact

Nasal Nitric Oxide (nasal + nitric_oxide)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Nasal Nitric Oxide in Children: A Novel Measurement Technique and Normal Values,,

THE LARYNGOSCOPE, Issue 10 2002
Hamid Daya FRCS (ORL)
Abstract Objectives To develop and standardize a technique for measuring nasal nitric oxide (NO) output in children and to determine normal values in this population. Study Design Prospective study evaluating a new technique for measuring nasal nitric oxide in a cohort of normal patients and a cohort of patients with nasal disease. Methods Nasal NO was measured using an aspiration technique, aspirating room air through the nasal cavities by means of a Teflon nozzle placed in one nasal vestibule while maintaining velopharyngeal closure using a party "blow-out" toy Results Nasal NO measurements were performed in 45 children (mean age, 11.0 y; age range, 3.2,17.6 y) There were 20 girls and 25 boys. All children were able to perform the maneuvers necessary for measurement of nasal NO output. Among the subgroup of normal healthy children (30), there was considerable variation in NO output between subjects, with a mean NO output of 481 nL/min and an SD of 283 nL/min. Conclusions Nasal NO can be readily measured in children using the presented technique. There is considerable variability in the values for nasal NO output in normal children. [source]

Nasal nitric oxide in objective evaluation of chronic rhinosinusitis therapy

ALLERGY, Issue 6 2006
S. M. Ragab
Background:, The assessment of the response of chronic rhinosinusitis (CRS) to therapy is difficult. Computerized tomographic (CT) scans cannot be repeatedly used so measures such as symptom scores, endoscopic findings, and parallel measures such as saccharin clearance time are employed instead. Objective:, To study the effect of CRS therapy on nasal nitric oxide and to see whether nasal nitric oxide level changes correlate with other assessments. Methods:, The study was a prospective randomized trial of patients with CRS, with or without polyps, who had failed initial medical therapy with douching and nasal corticosteroids and who then had abnormal CT scans. They were treated either medically or surgically, with follow up at 6 and 12 months whilst still taking nasal corticosteroids. Nasal nitric oxide was measured initially and at 6 and 12 months as well as symptom scores, endoscopy, polyp grading, and saccharin clearance time. Results:, Initial absolute nasal nitric oxide levels correlated inversely with CT scan changes, (P < 0.001). The percentage rise in nasal nitric oxide seen on both medical and surgical treatment correlated with changes in symptom scores (P < 0.001), saccharin clearance time (P < 0.001), endoscopic changes (P < 0.001), polyp grades (P < 0.05 at 6 months, P < 0.01 at 12 months) and surgical scores (P < 0.01). There was no significant correlation with age, sex, smoking or allergy. Conclusion:, Nasal nitric oxide, which is easily measured, provides a valuable non-invasive objective measure of the response of CRS to therapy. Topical nasal corticosteroids may be needed to reduce the contribution of nasal epithelial nitric oxide and allow that emanating from the sinuses to be measured. [source]

Nasal nitric oxide measurements before and after repeated humming maneuvers

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 12 2003
M. Maniscalco
Abstract Background, It has been recently shown that humming greatly increases nasal nitric oxide (NO). This is most likely owing to a rapid washout of sinus NO caused by the oscillating sound waves. During repeated humming manoeuvres nasal NO gradually decreases, likely because NO accumulated in the sinuses is washed out. Aim, We studied whether humming before measurements would affect nasally exhaled NO. Materials and methods, NO output was measured by the chemiluminescence technique in orally and nasally exhaled air in 38 subjects: 18 healthy subjects (HS), 15 subjects with allergic rhinitis (AR) and five subjects with allergic nasal polyposis (AP). Each subject performed a NO measurement during quiet nasal exhalation either preceded by a period of silence/free speaking or immediately after five consecutive humming manoeuvres (posthumming). Results, Mean nasal NO output (95% CI) after a period of silence/free speaking was 231 nL min,1 (178,284) in HS, 434 nL min,1 (347,522) in AR (P < 0·001) and 262 nL min,1 (163,361) in AP. Post-humming nasal NO output was 16% (5 to 50%) lower in HS and 14% (1 to 49%) lower in AR, while it remained unchanged in AP subjects. Intra-subject coefficient of variation of quiet nasal exhalation was 12% in HS, 13% in AR and 5% in AP. Post humming intraindividual coefficient of variation significantly decreased in both HS and AR, but it did not change in AP. Conclusions, Nasal NO levels measured immediately after repeated humming manoeuvres are consistently lower and more reproducible than nasal NO levels measured after a period of silence or free speaking. Repeated humming effectively empties the sinuses, thereby probably minimizing the normal contribution from the sinuses to nasal NO. This may be useful to better estimate NO output from the nasal cavity mucosa in health and disease. [source]

Nasal nitric oxide in objective evaluation of chronic rhinosinusitis therapy

Nasal Nitric Oxide in Children: A Novel Measurement Technique and Normal Values,,

Hypoxia Depresses Nitric Oxide Output in the Human Nasal Airways

THE LARYNGOSCOPE, Issue 3 2000
James S. J. Haight MD
Abstract Objectives The role of oxygen in the nasal air on nasal nitric oxide (NO) output was studied in 13 adult volunteers. Methods Nasal NO was measured while air containing oxygen (0%,100% in nitrogen) was aspirated through the nasal airway before and after the topical application of xylometazoline. Results The mean nasal NO output of the untreated nose was 507.8 ± 161.9 nL/min (mean ± SD) when 21% oxygen was aspirated through the nasal cavities in series and remained unaltered by 100% O2 (P = .79). Below 10% oxygen the reduction in nasal NO output correlated positively and significantly with the decrease in oxygen concentration (r2 = 0.14). NO output was 245.2 ± 153.4 nL/min at 0% oxygen, a significant decline from 21% oxygen (P < .0001). Nasal vasoconstriction induced by xylometazoline and alterations in the blood oxygen content by a maximal breath-holding or breathing 100% oxygen did not alter nasal NO in hypoxia (P = .41). Conclusions Nasal NO output is markedly depressed in hypoxia and is oxygen dependent at concentrations of less than 10%. Approximately 50% of nasally generated NO is produced from oxygen in nasal air or regulated by it. [source]

Nitric oxide evaluation in upper and lower respiratory tracts in nasal polyposis

CLINICAL & EXPERIMENTAL ALLERGY, Issue 7 2008
C. Delclaux
Summary Background A decrease in nasal nitric oxide (NO) and an increase in exhaled NO have been demonstrated in patients with nasal polyposis (NP). Objectives The aims were to evaluate the flux of NO from the three compartments of the respiratory tract, namely, upper nasal, lower conducting and distal airways, and to search for relationships between NO parameters and indexes of upper and lower disease activity (bronchial reactivity and obstruction). The effect of medical treatment of polyposis was also evaluated. Methods Seventy patients with polyposis were recruited. At baseline, pulmonary function tests (spirometry, plethysmography, bronchomotor response to deep inspiration using forced oscillation measurement of resistance of respiratory system, methacholine challenge, multiple flow rates of exhaled NO and nasal NO measurements) were performed together with an assessment of polyposis [clinical, endoscopic and computed tomography (CT) scores]. Results Statistical relationships were demonstrated between nasal NO flux and severity scores (clinical: ,=,0.31, P=0.015; endoscopic: ,=,0.57, P<0.0001; CT: ,=,0.46, P=0.0005), and between alveolar NO concentration and distal airflow limitation (FEF25,75, ,=,0.32, P=0.011). Thirty-six patients were assessed after 11 [7,13] (median [interquartile]) months of medical treatment, demonstrating an improvement in clinical and endoscopic scores, an increase in nasal NO flux, a decrease in NO flux from conducting airways, an improvement in the mild airflow limitation (forced expiratory volume in 1 s, FEF25,75, even in non-asthmatic patients) and a decrease in the bronchoconstrictor effect of deep inspiration. Conclusions The medical treatment of NP improves both airway reactivity and obstruction, whatever the presence of asthma, suggesting a functional link between upper and lower airway functions. [source]

Exhaled and nasal nitric oxide in mechanically ventilated preterm and term newborns

ACTA PAEDIATRICA, Issue 10 2002
O Aikio
Aim: Nitric oxide (NO) is an important mediator required for neonatal pulmonary circulatory adaptation and for pulmonary defence. Both deficient and excessive NO production have been proposed to play a role in neonatal lung disease. This study aimed to establish a method that allows direct measurement of exhaled and nasal NO concentrations in newborn infants who require intubation and ventilation. Methods: A rapid-response chemiluminescence NO analyser was used. Gas was sampled from the endotracheal intubation tube, and tidal volumes and flow rates were measured. The nasal NO was sampled from the non-intubated nostril. The accuracy of the method was validated using a lung model. NO levels from six preterm and six term/near-term newborns were studied. Measurements were performed on a daily basis during the first week. Results: An expiration >0.2 s in duration with a flow rate >1.7mls,1 could be accurately analysed for the presence of >1 parts per billion of NO. The very preterm infants with neonatal lung disease had a different postnatal NO output pattern from the lower and upper airways compared with the ventilated term/near-term infants. Conclusion: A novel method for measurement of exhaled NO of an intubated newborn is presented. The possible association of exhaled NO concentration with the development of chronic lung disease remains to be studied. [source]