RESUMEN
The sampling of exhaled breath is a noninvasive procedure that can be performed easily in adults, children, and patients with respiratory disease. Several studies have demonstrated increased exhaled nitric oxide in patients with pulmonary disease, including asthma. In addition, exhaled nitric oxide may be an elegant tool for monitoring of environmental health effects of air pollution and the prevalence of atopy in epidemiological surveys. Recent literature about exhaled nitric oxide is presented in this article. Technical, physiological, and behavioral confounding factors of exhaled nitric oxide measurement are outlined.
Asunto(s)
Pruebas Respiratorias , Contaminantes Ambientales/análisis , Enfermedades Pulmonares/diagnóstico , Óxido Nítrico/análisis , Biomarcadores/análisis , Factores de Confusión Epidemiológicos , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/efectos adversos , Métodos Epidemiológicos , Monitoreo Epidemiológico , Humanos , Estilo de Vida , Enfermedades Pulmonares/etiología , Sensibilidad y EspecificidadRESUMEN
The authors sought to determine which air pollutant is responsible for the increase in exhaled nitric oxide observed in healthy subjects. Exhaled nitric oxide was measured in 16 nonsmoking healthy subjects on 14 workdays, during which there were varying air-pollution levels. Contamination of samples by ambient nitric oxide was excluded. The baseline value of exhaled nitric oxide, determined at times when outdoor air pollution was low, ranged from 7 to 43 ppb (mean = 28+/-5 ppb). The daily value of exhaled nitric oxide (range = 5-60 ppb) was associated positively with ambient carbon monoxide (r = .85) and nitric oxide (r = .81). Exposure during the morning hours to high levels of outdoor pollution was associated with increased exhaled nitric oxide (i.e., 50% above baseline), which persisted for up to 5 h (i.e., 32% above baseline). These results indicated that exhaled nitric oxide levels represent a useful biomonitor of individual exposure to air pollutants.
Asunto(s)
Contaminación del Aire/efectos adversos , Pulmón/metabolismo , Óxido Nítrico/metabolismo , Adulto , Biomarcadores , Femenino , Humanos , Masculino , Países Bajos , Valores de ReferenciaRESUMEN
OBJECTIVES: The aim of the present study was to evaluate the balloon procedure to measure exhaled nitric oxide (NO). METHODS: This was performed by comparing the procedure with the well-established on-line measurement of NO (direct exhalation into the NO module). Using both procedures exhaled NO was measured in 16 healthy subjects on two days with different level of air pollution. RESULTS: Exhaled NO measured on-line was 3.8-4.5 times lower than exhaled NO obtained using the balloon technique but the two sets of values correlated linearly (r 0.93-0.97). Mean NO level on day 1 with low air pollution and day 2 with high air pollution was 6.6 and 8.1 parts per billion (ppb; on-line measurement) and 25.2 and 36.9 ppb (balloon method), respectively. The day 1 to day 2 ratio differed per subject but was independent of the technique of measurement. Mean day-to-day ratio of exhaled NO using the balloon technique (1. 65 +/- 0.13) was not different (P < 0.05) from the ratio of NO levels measured on-line (1.49 +/- 0.13). Based on these ratios the increase in level of outdoor air pollution appears to be associated with a 49-65% increase in exhaled NO. CONCLUSION: Exhaled NO is proposed as a de novo individual biomarker to monitor the adverse effects of air pollution. The balloon procedure offers a sound and convenient alternative for the on-line procedure to measure exhaled NO in large populations as required in epidemiological studies.