Application of a Constant Indicator Dilution Method to the Measurement of Local Venous Flow

Abstract
A method for measuring local venous flow by a constant indicator dilution technique is described. The optimal conditions have been outlined and the accuracy tested in vitro and found to be within ±3%. When compared with direct measurements of venous flow in dogs, its accuracy was within ±5%. The method is safe, easy to perform and, with the catheters described, flow can be measured over ranges of 20 to 5,700 ml/min in any vein greater than 4 mm inner diameter in which the catheter tips can be introduced.