The role of nitric oxide in predicting revisit of patients with exacerbated chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is associated with high mortality and morbidity. OBJECTIVE: The aim of the present study was to determine the role of nitric oxide (NO) and other possible factors in predicting the revisit of patients with COPD exacerbation to the emergency department (ED). METHODS: This is a prospective cohort study on patients with exacerbated COPD in the ED setting. Bedside nasal NO values were measured with a hand-held analyzer device. Revisit to the ED has been defined as any unscheduled visit to an ED or to primary physician's office within 2 weeks of the initial ED visit for worsening COPD symptoms. A follow-up survey via telephone was conducted on all patients at the end of 2 weeks. RESULTS: The data from 64 patients who visited the ED once was compared to 28 revisits. Total of 92 patients were analyzed and variables were compared. The rate of revisits to the ED was 30%. Nasal NO measurement could not predict the revisits of patients with COPD exacerbation to the ED. The mean respiratory rate, exacerbations in previous year, home nebulizer therapy, prescribed antibiotic at discharge, home oxygen therapy, and abnormal chest x-ray studies were associated with increased rate of revisits to ED in univariate analysis. After multivariate analysis, only the mean respiratory rate at presentation and the prescribed antibiotic at discharge were significant determinants. CONCLUSIONS: There was no statistically significant difference measured in NO level at presentation or before discharge between the groups. The mean respiratory rate at presentation and the prescribed antibiotic at discharge may predict the return of a COPD-exacerbated patient within 14 days to ED.