Objective To investigate the effect of heat and moisture exchange filter on airway inflammatory response in normal subjects and patients with chronic obstructive pulmonary disease(COPD) during inhalational anesthesia. Methods Eighty subjects undergoing abdominal surgery and inhalational anesthesia were randomly identified as normal or COPD(classⅠ or ⅡA) by history-taking and the pulmonary function testing.Both types of subjects were randomized into groups of none HMEF and with HMEF,using disposable corrugated tubing or HMEF in the ventilator breathing systems.The patients were intubated with left-side double-lumen endotracheal tubes.The venous blood and BAL were sampled at 0,2,4 hours after intubation.And leukocyte counts and cytokines(TNFα、IL-1β、IL-2、IL-6、IL-8) in bronchoalveolar lavage fluid(BALF) and blood samples were assayed.Results The TNF-alpha levels(632 +/-146 vs.763 +/-157 pg/ml,respectively,p=0.0098) and IL-8(353+/-195pg/ml vs.526+/-142pg/ml,respectively,p=0.0028) in BALF were significantly lower at 4h following mechanical ventilation in COPD patients with HMEF than those without HMEF. However,there is no significant difference in leukocyte counts and cytokine levels between normal subjects with or without HMEF.Conclusion HMEF could reduce the airway inflammatory response in patients with COPD during inhalational anesthesia and mechanical ventilation.
