icd_nine	parameter
490	Bronchitis, not specified as acute or chronic
491	Chronic bronchitis
491.0	Simple chronic bronchitis
491.1	Mucopurulent chronic bronchitis
491.2	Obstructive chronic bronchitis
491.20	Obstructive chronic bronchitis without exacerbation
491.21	Obstructive chronic bronchitis with (acute) exacerbation
491.22	Obstructive chronic bronchitis with acute bronchitis
491.8	Other chronic bronchitis
491.9	Unspecified chronic bronchitis
492	Emphysema
492.0	Emphysematous bleb
492.8	Other emphysema
494	Bronchiectasis
494.0	Bronchiectasis without acute exacerbation
494.1	Bronchiectasis with acute exacerbation
496	Chronic airway obstruction, not elsewhere classified