The effect of changes in the rate of perfusion and oxygen tension (PO2) on theophylline clearance was determined in the rat isolated perfused liver. Changes in rate of perfusion had no effect on the extraction ratio of theophylline while a decrease in the PO2 significantly increased the half life of theophylline. These results suggest that changes in PO2 whether due to disease states or oxygen administration may necessitate theophylline dosage adjustment.
Animals Half-Life