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PubMed1998

Exhaled nitric oxide and bronchial reactivity during and after inhaled beclomethasone in mild asthma.

The measurement of exhaled nitric oxide (ENO) is recognized as a marker of airway inflammation. ENO was measured in 10 nonsteroid-treated asthmatics at recruitment, during 3 weeks of inhaled beclomethasone (1000 microg/day) and for 3 weeks after withdrawal. Baseline ENO was increased in asthma compared with nonasthmatics (85.0+/-54.5 vs. 24.5+/-14.8 ppb, p < 0.0001). After inhaled steroid, there was no significant change in forced expiratory volume in 1 sec (FEV1) and forced vital capacity (FVC), but methacholine PC20 rose significantly (p = 0.0345). ENO (mean+/-SD; % baseline) fell after 1 week on steroid to 60.6+/-31.1 and rose to 95.3+/-46.1 at 1 week after withdrawal. ENO did not correlate with PC20 or FEV1. The changes in ENO and PC20 were inversely correlated (r2 = 0.325). ENO may be an index of airway inflammation and therapeutic response in bronchial asthma.

Administration, Inhalation↗
PubMed1999

Circadian variation in exhaled nitric oxide in nocturnal asthma.

Asthma is characterized by airway inflammation and shows a circadian variation with nocturnal exacerbations. Because exhaled nitric oxide (ENO) measurement appears to be a noninvasive marker of airway inflammation, we examined the hypothesis that ENO would increase at night. In five nocturnal and five non-nocturnal asthmatics, ENO was measured at 4 P.M., 10 P.M., and 4 A.M. before and after bronchodilator. Both pre- and post-bronchodilator ENO (mean pre- and post-bronchodilator +/- SEM, ppb) unexpectedly fell significantly in nocturnal asthma from 4 P.M. (77.2 +/- 8.2) compared to 10 P.M. (68.4 +/- 8.7, p < 0.003) and 4 A.M. (66.0 +/- 8.5, p < 0.001) with no significant difference between 10 P.M. and 4 A.M.. In contrast, there were no significant differences in mean ENO at 4 P.M., 10 P.M., and 4 A.M. in non-nocturnal asthma. (51.3 +/- 10.8, 57.7 +/- 13.4, 53.8 +/- 12.5 ppb, respectively). Following bronchodilator, ENO rose significantly by 10.5 +/- 1.8 ppb in the nocturnal asthma group alone. The circadian rhythm of ENO differed greatly between nocturnal and non-nocturnal asthma. The significant decrease in ENO in nocturnal asthma may reflect an important chronobiological defect in the endogenous production and/or increased disposition of nitric oxide, which in view of its bronchodilator action, could play a role in nocturnal exacerbations of asthma.

Adult↗
PubMed2003

Possible association between passive smoking and lower exhaled nitric oxide in asthmatic children.

In adults, both active and passive smoking reduce levels of exhaled nitric oxide (eNO); however, to date, passive exposure to environmental tobacco smoke (ETS) has not been shown to affect eNO in children. The authors recruited 174 asthmatic children (96 male, 78 female) and 79 nonasthmatic controls (46 male, 33 female) from a group of children aged 5 to 14 yr who attended a children's hospital for an outpatient visit or elective surgery. Each subject's exposure to ETS was ascertained by questionnaire, and their eNO levels were measured. Asthmatic children had higher eNO levels (ppb) than nonasthmatic children (p = 0.04), and asthmatic children exposed to ETS had significantly lower eNO levels than unexposed children (p = 0.005). Exposure to ETS did not alter eNO levels in nonasthmatic children (p = 0.4). Results of the study suggest that ETS exposure is associated with lower eNO levels among childhood asthmatics. Consequently, ETS exposure may need to be considered when physicians interpret eNO levels in asthmatic children. Further study of the effects of ETS on eNO levels is recommended.

Adolescent↗
PubMed2004

Exhaled nitric oxide: sources of error in offline measurement.

Delayed offline measurement of exhaled nitric oxide (eNO), although useful in environmental and clinical research, is limited by the instability of stored breath samples. The authors characterized sources of instability with the goal of minimizing them. Breath and other air samples were stored under various conditions, and NO levels were measured repeatedly over 1-7 d. Concentration change rates varied positively with temperature and negatively with initial NO level, thus "stable" levels reflected a balance of NO-adding and NO-removing processes. Storage under refrigeration for a standardized period of time can optimize offline eNO measurement, although samples at room temperature are effectively stable for several hours.

Adolescent↗
PubMed1986

Exhaler class: a multidisciplinary program for high quadriplegic patients.

The Exhaler Class at Craig Hospital was developed to meet the physical, psychosocial, and educational needs of high quadriplegic patients. The class uses a multidisciplinary approach and includes exercise and educational sessions. To date, a total of 56 patients have participated in the 6-week program, and those surveyed rated the sessions as good both in content and presentation. An average increase in vital capacity of 0.5 L was observed in 20 patients surveyed.

Exercise Therapy↗
PubMedDate not supplied

Minimal exhaled nitric oxide production in the lower respiratory tract of healthy children aged 2 to 7 years.

BACKGROUND: Exhaled nitric oxide (eNO) is elevated in inflammatory airway conditions, e.g. asthma. We measured eNO levels in normal preschool children for whom there is little data available and in whom the prevalence of asthma is high. SUBJECTS AND METHODS: Fifty children, 2-7 years old, undergoing elective surgery, excluding airway procedures, were recruited. Children with known respiratory disease or acute viral infections were excluded. Gas for eNO measurement was collected in a non-diffusion bag via 1) the mask after inhalation induction of anesthesia, 2) endotreacheal tube (ETT) or laryngeal mask airway (LMA), and 3) during emergence. Measurement was off-line by chemiluminescent analyzer. RESULTS: Mean eNO level by mask was 10.23 ppb (mean value+/-SD of 8.8-11.1 ppb) after induction and 8.35 ppb (mean value+/-SD of 5.9-10.8 ppb) on emergence. Mean eNO for the intubated group (n=25) was 0.75 ppb (mean value+/-SD of 0.4-1 ppb) (P<0.0001 vs mask); mean eNO for the LMA group (n=25) was 2.6 ppb (mean value+/-SD of 2-3.2 ppb), which differed from the mask (P<0.0001), and from ETT values (P<0.0001). CONCLUSIONS: Most eNO is produced by the upper airway in healthy pre-school children. The lower airway constitutive eNO production is very low. The LMA does not completely isolate the upper airway and current mask collection techniques allow significant contamination of samples by sino-nasal eNO production in young children.

Child↗
PubMed1999

Exhaled nitric oxide in patients with sleep apnea.

Cardiovascular diseases are frequent in patients with obstructive sleep apnea syndrome (OSAS), but the mechanisms underlying this association are largely unknown. Nitric oxide (NO) is a key regulatory element of vascular physiology. The concentration of NO in the exhaled air ([NOexh]) appears to be reduced in patients with systemic and pulmonary hypertension. This study sought to investigate whether [NOexh] is abnormal in patients with OSAS, and to explore potential relationships between [NOexh] and the severity of OSAS. We measured [NOexh] in 24 patients with OSAS (apnea-hypopnea index (AHI), 55 +/- 4 hour-1) (x +/- SEM), and in 7 healthy volunteers in whom OSAS was excluded clinically. [NOexh] was measured on line by a chemiluminescence analyzer (Dasibi Environmental Corporation, Glendale, Calif). Seven patients with OSAS (29%) had a positive history of cardiovascular disease. Mean [NOexh] was 19.7 +/- 3.2 ppb in healthy subjects, and 22.2 +/- 3.0 ppb in patients with OSAS (p = ns). [Noexh] was not significantly different in those patients with or without cardiovascular disease. [NOexh] was not significantly related to the AHI, the body mass index, or the arterial O2 saturation at night. These results show that [NOexh] is not abnormal in patients with OSAS, and that it does not relate to the presence of cardiovascular disease or to any of various common indices of disease severity.

Adult↗
PubMed2000

Asthma severity, recommended changes of inhaled therapy and exhaled nitric oxide in children: a prospective, blinded trial.

Orally exhaled nitric oxide (ENO) correlates with several variables of airway inflammation and might be useful to direct asthma therapy. If this is true, ENO should correlate with disease severity and the therapeutic decisions made. - In 74 children with allergic asthma (age 9.7 years, range 4-16) disease severity was determined by history, clinical symptoms, and lung function and inhaled therapy was adjusted according to the NIH criteria. ENO was also measured, but the patients, their parents and the physicians who made the therapeutic decision were left unaware of the results. 31 healthy children served as controls. ENO was higher in asthmatics than in controls, but did not differ with asthma severity. ENO was weakly correlated with the changes in asthma therapy recommended (r = 0.303, P = 0.009). ENO values above normal (> 13 ppb) had a sensitivity of 0.67 and a specificity of 0.65 to predict a step up in therapy. Due to the non-normal distribution of ENO there was a substantial overlap between the different groups. The lack of correlation with disease severity and the weak prediction of physician recommended inhaled therapy, suggest that ENO may be of some value to guide asthma therapy. Studies using ENO to direct therapy are necessary for a definite answer.

Asthma↗
PubMed2001

Exhaled nitric oxide after inhalation of isotonic and hypotonic solutions in healthy subjects.

Airway nitric oxide (NO) homoeostasis is influenced by chemical and mechanical stimuli in humans; airway epithelium, which is an important site of NO production, is sensitive to osmotic challenge. The effect of inhaled hypotonic solutions on exhaled NO (eNO) is not known. In this study we evaluated the effect of ultrasonically nebulized distilled water (UNDW), a hypotonic indirect stimulus, on eNO levels. A total of 10 non-smoking healthy subjects were enrolled in the study. eNO was detected by chemiluminescence, and specific airway conductance (sGaw) was measured by plethysmography. Bronchial challenges with UNDW and with an isotonic solution were performed according to a double-blind experimental design. Baseline levels of eNO were 28.1+/-14.7 p.p.b. UNDW did not cause any significant change in sGaw (from 0.190+/-0.029 to 0.181+/-0.036 cm H(2)O x s(-1)). With respect to baseline values, the eNO concentration decreased significantly after inhalation of 8 or 16 ml of UNDW (from 26.0+/-13.1 to 17.2+/-8.5 and 16.6+/-7.7 p.p.b. respectively; P<0.001, n=10). After bronchial challenge with UNDW, eNO was significantly reduced in comparison with after inhalation of the isotonic solution. In five subjects, pretreatment with N(G)-nitro-L-arginine methyl ester (L-NAME), an inhibitor NO synthesis, decreased NO levels from 21.7+/-8.5 to 10.0+/-3.3 p.p.b. Subsequent inhalation of 16 ml of UNDW did not cause any further decrease in NO levels (10.1+/-3.7 p.p.b.; not significant compared with L-NAME). We conclude that inhalation of aqueous solutions decreases eNO levels in healthy subjects, and that this effect is not associated with any significant change in airway calibre. The UNDW-induced decrease in eNO is not enhanced by pretreatment with the NO synthase inhibitor L-NAME, suggesting that inhaled solutions may interfere with the airway NO pathway in humans.

Adult↗
PubMed2002

Unilateral expiratory airflow obstruction during forced exhalation.

We present a case of unilateral airflow obstruction during forced exhalations. The patient presented with episodic dyspnea and wheezing, particularly when he lay in the right lateral decubitus position. Spirometry revealed symmetric, marked reductions in forced expiratory volume in the first second and forced vital capacity values, while plethysmography demonstrated a near-normal total lung capacity. Bronchoscopy revealed a polypoid lesion in the right main bronchus, of which biopsy specimens demonstrated adenoid cystic carcinoma. Following a right pneumonectomy, total lung capacity was markedly reduced; interestingly, however, spirometry was essentially unchanged. This case is an elegant illustration of the effects of respiratory maneuvers and body position on airway caliber.

Airway Obstruction↗
PubMed1975

[Exhalation diagnosis with C14 tagged compounds, methods and results].

The method and results of the 14C exhalation test for metabolic studies are presented. In patients under radiotherapy for malignant diseases (we consider radiotherapy to be a well defined metabolic disturbance), studies with 14C-carboxyl triglycerides, with 14C-glycincholate, with 14C-histidine and with 14C-uridyl reveal the extent of the metabolic changes and also how long it would take to return to the normal state. It is not yet well understood why a disturbace of glycincholate absorption persists for years after radiotherapy of the pelvis. The method can also be employed in gastroenterology (absorption of bile salts) and in assessing an anabolic or catabolic state as af function of thyroid hormone. Further metabolic tests for radiobiologic evaluations are in progress.

Bile Acids and Salts↗
PubMed2002

[Analysis of nasal and exhaled nitric oxide concentration in nasal polyposis].

UNLABELLED: Nitric oxide (NO) is implicated in the pathophysiology of inflammatory airway diseases. It has been identified as a potential marker of airway inflammation. OBJECTIVE: The purpose of the study was to assess the concentrations of nasal NO in upper and lower airways in nasal polyposis patients. PATIENTS: 18 nasal polyposis patients (14 men, 4 women) and 21 control subjects (7 men, 14 women), all non asthmatic non smokers, without respiratory infections were prospectively studied. METHODS: They included nasal obstruction scoring, nasal endoscopic grading, allergy testing, nasal cytology, flow-volume spirometry and measurement of nasal (NNO) and exhaled NO (ENO) concentrations. NO was measured by a chemiluminescence NO Analyser (Sievers 280). NNO was analysed by aspiration with a constant flow of 3 l/mn. ENO was analysed during a slow expiration (50 ml/s) against a constant resistance of 10 cm H2O. RESULTS: NNO was significantly (p<0,001) decreased in NP group (596.4 +/- 102.06 ppb) compared to control group (2 251.6 +/- 288.6 ppb). ENO was significantly (p<0.05) increased in NP group (45.4 +/- 14.1 ppb) compared to control group (11.2 +/- 1.16 ppb). NNO and ENO were not significantly different between atopic and non-atopic NP patients. NNO concentrations was inversely correlated with the values of nasal endoscopic grading. No correlation was found between NNO concentrations and respectively nasal obstruction scoring and eosinophil count in nasal mucosa. CONCLUSION: Further studies are necessary to understand the pathophysiology of decreasing NNO and increasing ENO in nasal polyposis. In particular, ENO could be consider as a biologic marker of lower airway inflammation in nasal polyposis.

Adult↗
PubMed2003

[Correlation between carbon-monoxide levels in exhaled air and nicotine-dependence measurements systems (DSM-IV, Fagerström test and ARU-SMQ-9) in adolescent smokers].

BACKGROUND AND OBJECTIVE: If we are capable of 1) determining the correlation, in young smokers, between carbon-monoxide levels in exhaled air (CO) and carboxihemoblobine (COHb) (cooximetrically determined) and 2) adapting the versions of the nosologic criteria DSM-IV for nicotine-depencence (DSM-IVa), Fagerström Test (FTNDa), and ARU-SMQ-9a Test to adolescents, then we may be able to establish how useful such tests are to measure nicotine-ependences in adolescents. SUBJECTS AND MEHTOD: Cross-sectional, observation-based study carried out in 41 schools. 2,647 students aged 10 to 17 years were surveyed. The size of the sample was calculated for eacha nd using the equation of finite population. For each age, the sample was stratified according to sex and type of school. Schools and students were chosen by using the table of random numbers. Teenagers filled up a questionnaire which included DSM-IVa, FTNDa, and ARU-SMQ-9a and were subsequently given a cooximery. RESULTS: 23.1% were smokers. The correlation between the levels of CO and the nicotine-dependence tests was: DSM-IVa rho o = 0.3390 (p = 0.0000); FTNDa rho o = 0.5853 (p 0 0.000); ARU-SMQ-9a rho o = 0.4670 (p = 0.000). The correlation with the levels of carboxihemoglobine was: DSM-IVa rho o = 0.3369 (p = 0.000); FTNDa *o = 0.5498 (p = 0-000); ARU-SMQ-9a rho o = 0.4460 (p 0 0-000). The study was based on 583 smoking scholars who underwent the cooximetry. CONCLUSIONS: The correlation between DSM-IVa, FTNDa, and ARU-SMQ-9a and the levels of CO and COHb in young smokers is low but meaninful. In our opinion, research to find new, simple, cheap, and easily-accessible tools allowing the correct diagnosis and follow-up of young smokers must continue.

Adolescent↗
PubMed1992

[Value of exhaled air acetone level in assessing the impairement of secretory pancreatic function in acute destructive pancreatitis].

For the first time, a semiconductor gas sensor of original construction was employed to measure acetone level in the biologic liquids and gases in patients with acute destructive pancreatitis. A statistically significant difference in acetone level in the exhaled air of the healthy subjects, patients with edematous and destructive forms of acute pancreatitis and diabetes mellitus has been established.

Acetone↗
PubMed2003

[The test for nitric oxide metabolites in exhaled air condensate as a method of assessing NO-reactivity of the airways in patients with bronchial asthma].

AIM: To estimate airways NO-reactivity in response to their stimulation with fenoterol in different clinical forms of bronchial asthma (BA). MATERIAL AND METHODS: The study included 73 patients with BA: mild disease was in 21, moderate--in 24 and severe--in 28 patients. Severe BA patients were divided into two subgroups: with a stable course (n = 15) and unstable course (n = 13). NO-producing function of the airways was estimated by concentration of stable NO-metabolites (mNO)(NO2, NO3) in exhaled air condensate. RESULTS: Spontaneous NO-producing activity of the airways increases and reaches maximum in severe unstable asthma. Fenoterol-stimulated NO-production was minimal in mild BA while the most significant augmentation of mNO was observed in unstable BA. Basal level of mNO and velocity parameters of external respiration function correlated. CONCLUSION: Estimation of NO-reactivity of the airways in the test with fenoterol with calculation of the index of airways NO-reactivity provides additional information about respiratory system condition in BA patients which may be used in clinical pulmonology.

Asthma↗
PubMed2004

[Does cardiac resynchronization therapy improve nitric oxide concentration in exhaled gas?].

OBJECTIVES: Cardiac resynchronization therapy (CRT) is widely known to improve cardiac function in patients with chronic heart failure, especially those with increased intraventricular conduction delay. However, whether vascular endothelial cell function is improved remains unknown. Capability of nitric oxide (NO) production is a good marker to evaluate endothelial cell function. Therefore, NO output was measured in exhaled air in patients with chronic heart failure after CRT. METHODS: Six patients with chronic heart failure and dilated cardiomyopathy (mean age 62.0 +/- 11.3 years, left ventricular ejection fraction 22.8 +/- 11.6%) received CRT. Pacing leads were lodged at the right atrium, the apex of the right ventricle and at the mid portion of the postero-lateral branch of the coronary sinus. One month after CRT, endtidal NO concentration was evaluated with and without pacing using the chemiluminescence method. RESULTS: Left ventricular ejection fraction improved from 22.8% to 28.8% after the procedure. Endtidal NO was significantly (p = 0.038) increased from 64.7-13.2 ppb without pacing to 69.1-14.1 ppb with pacing. Respiratory rate (with pacing: 19.7-5.7 n/min, without pacing: 20.3-4.8 n/min), tidal volume (with pacing: 523.2-122.7 ml, without pacing: 516.2-160.3 ml) and minute ventilation were not changed. CONCLUSIONS: CRT did not affect respiratory rate, tidal volume or minute ventilation, so increased endtidal NO did not result from enhanced production from tracheal and/or bronchial epithelial cells. Therefore, endtidal NO increased because chronic heart failure increased pulmonary perfusion and so raised vascular shear stress. CRT for patients with dilated cardiomyopathy can improve vascular endothelial cell function.

Aged↗
PubMed2004

Cardiopulmonary exercise testing and exhaled nitric oxide in the assessment of patients with mitral stenosis.

AIM: In patients with mitral stenosis, symptoms do not always correlate with echocardiographic data. The aims of the study were to evaluate the role of cardiopulmonary exercise testing in the assessment of patients with mitral stenosis and to quantify nitric oxide production at rest and at the end of exercise. METHODS: We evaluated 43 patients with moderate to severe mitral stenosis with a discrepancy between echocardiographic data and symptoms. Nitric oxide output was calculated by measuring nitric oxide concentration in the exhaled air at rest and at the end of exercise test. RESULTS: Patients were divided in 2 groups: group 1 with a functional capacity <75% at cardiopulmonary exercise test (VO2max in % of the predicted one) and group 2 with functional capacity >75%. Transvalvular gradient and pulmonary artery pressure were significantly higher in group 1 than in group 2 (respectively 9.07 +/- 2.11 mmHg vs 6.01 +/- 1.08 mmHg, p<0.001 and 42.8 +/- 7.2 mmHg vs 33.1 +/- 4.7 mmHg, p<0.001). Patients of group 1 had a lower nitric oxide output at the end of exercise compared to group 2 (231.4 +/- 96.6 nl/min vs 326.3 +/- 74.0 ml/min, p=0.01) and to normal subjects (511.15 +/- 180.1 nl/min, p<0.001). CONCLUSION: Cardiopulmonary exercise testing provides objective non invasive information in the evaluation of patients with discrepancy between symptoms and echocardiographic data. Different levels of nitric oxide output during exercise suggest the role of nitric oxide in regulating pulmonary vascular tone.

Adult↗
PubMed2004

[Vapor condensate of exhaled air in evaluating the impaired metabolism of the bronchopulmanory system in nonspecific lung diseases].

The degree of metabolic rehabilitation of the bronchopulmonary system was evaluated in non-specific pulmonary diseases, like pneumonia or chronic obstructive bronchitis, by using the data of biochemical testing of the exhaled-air vapor condensate. Nine parameters were investigated, i.e. enzymes alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase, alkaline phosphatase (AP), gamma-glutamate amino-transpeptidase (GGT) as well as parameters of protein metabolism--common protein, seromucoid (SC), C-reactive protein and urea. AST, ALT, AP, GGT, SC and urea were acknowledged as the most informative parameters. The results are indicative of that the recovery of metabolic processes in the bronchopulmonary system was not completed.

Adolescent↗