Abstract
Pharmacokinetic parameters were calculated from a total of 1167-time samplings in 354 attacks of 164 cases of asthmatic infants and children between 0 to 15 years of age. Distribution volume (Vd) was caluculated after 15 minutes infusion in 118 times of asthma attcks of 76 cases. Interpatient mean value and standard deviation (SD) of these Vd were 392±103ml/kg (CV*=26.3%), and intrapatient mean CV was also 26.3%.
And Vd was also caluculated after 2 hours infusion in 184 times of attacks of 114 cases. Interpatient values of these Vd were 408±54.6ml/kg (CV=13.3%), and intrapatient mean CV was also 13.1% respectively. Elimination rate constant (Ke) was caluculated 639 times in 156 cases after several hours of maintenance doses. Interpatient mean and SD of these Ke were 0.160±0.0417/h (CV=26.1%), and intrapatient mean CV was also as large as 32.0%. Clearance (CL) was caluculated 226 times in 86 cfses after over 12 hours of maintenance doses. Interpatient mean and SD of these CL were 57.4±13.9ml/kg/h (CV=24.2%), and intrapatient mean CV was as small as 19.3%.
From these results, it was shown that Vd caluculated after 2-hour infusion and individual mean values of CL are better and more suitable for making individual aminophylline infusion program, compared with the Vd caluculated after 15 minutes infusion and Interpatient CL. *CV: Coefficient of variation. CV=SD±Mean×100(%)
