MULTIPLE FLOW RATE MODELLING OF NITRIC OXSDE iN CQPD - METHODOLOGICAL CONCERNS

摘要

Multiple flow rates Fe_(NO) data two-compartment mathematical modelling can estimate NO airway wall concentration (Caw_(NO)). airway wall diffusing capacity (Daw_(NO)), alveolar concentration (Calv_(NO)) and maximal NO flux (Jaw_(NO)). To compare modelling based on linear, non linear and mixed linear and non linear analyses in COPD. Fe_(NO) was measured using the Niox analyser (Aerocrine) at flow rates: 10. 30, 50,100 and 200ml,s in 50 COPD patients and the data applied to 4 different methods. All methods showed that current smoking reduced Caw_(NO). Jaw_(NO) data differed between methods (Table 1). All the methods showed that current smoking did not affect Calv_(NO) or Daw_(NO)- Comparison of the methods showed that CalvN0 and Daw_(NO) data were significantly different between all methods. Jaw_(NO) was different for most between method comparisons, while there was agreement between all the methods for Caw_(NO). Smoking in COPD reduces Caw_(NO). but not CalvN0 and Daw_(NO). Jaw_(NO), Calv_(NO) and Daw_(NO) data are model dependent parameters. Caw_(NO) findings were model independent, and hence the most robust modelled parameter.