Theophylline: constant-rate infusion predictions.
This study was undertaken to evaluate a method of prospectively estimating appropriate aminophylline infusion rates in acutely ill, hospitalized patients with bronchospasm. Steady-state serum theophylline concentrations (Css), clearances (Cl), and half-lives (t1/2) were estimated by the Chiou method using serum concetrantions obtained 1 and 6 h after the start of a constant-rate intravenous aminophylline infusion in 10 male patients averaging 57 years of age. Using an enzyme-multiplied immunoassay (EMIT) system for theophylline analysis, pharmacokinetic estimations were excellent for Css (r = 0.9103, p less than 0.01) and Cl (r = 0.9750, p less than 0.01). The mean estimation errors were 9.4% (range 0.8-21.5) for Css and 12.3% (range 1.3-28.0) for Cl. There was no correlation between patient age and Cl. This method is useful for rapidly individualizing aminophylline therapy in patients with acute bronchospasm.
D000328:Adult; D000368:Aged; D000628:Aminophylline / Q000008:administration & dosage* / Q000378:metabolism; D001986:Bronchial Spasm / Q000097:blood* / Q000188:drug therapy; D006207:Half-Life; D006801:Humans; D007263:Infusions, Parenteral; D007700:Kinetics; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D012044:Regression Analysis; D013806:Theophylline / Q000097:blood* / Q000378:metabolism / Q000627:therapeutic use
D000628:Aminophylline; D013806:Theophylline