Non-asthmatic patients show increased exhaled nitric oxide concentrations

objective: evaluate whether exhaled nitric oxide may serve as a marker of intraoperative bronchospasm. introduction: intraoperative bronchospasm remains a challenging event during anesthesia. previous studies in asthmatic patients suggest that exhaled nitric oxide may represent a noninvasive measure of airway inflammation. methods: a total of 146,358 anesthesia information forms, which were received during the period from 1999 to 2004, were reviewed. bronchospasm was registered on 863 forms. from those, three groups were identified: 9 non-asthmatic patients (bronchospasm group), 12 asthmatics (asthma group) and 10 subjects with no previous airway disease or symptoms (control group). all subjects were submitted to exhaled nitric oxide measurements (parts/billion), spirometry and the induced sputum test. the data was compared by anova followed by the tukey test and kruskal-wallis followed by dunn's test. results: the normal lung function test results for the bronchospasm group were different from those of the asthma group (p <0.05). the median percentage of eosinophils in induced sputum was higher for the asthma [2.46 (0.45-6.83)] compared with either the bronchospasm [0.55 (0-1.26)] or the control group [0.0 (0)] (p <0.05); exhaled nitric oxide followed a similar pattern for the asthma [81.55 (57.6-86.85)], bronchospasm [46.2 (42.0 -62.6] and control group [18.7 (16.0-24.7)] (p< 0.05). conclusions: non-asthmatic patients with intraoperative bronchospasm detected during anesthesia and endotracheal intubation showed increased expired nitric oxide.