ABSTRACT
The chapter presents a general overview of rheological approaches to therapy. With linear increase in hematocrit, systemic oxygen transport capacity increases linearly, whereas blood viscosity increases logarithmically. Increase in total and local blood volume flow rates is the major mechanism by which systemic oxygen transport capacity is maintained during acute hemodilution. Donor human albumin may be provided as a solution or as a freeze-dried powder for reconstitution with sterile water immediately before transfusion. Hydrodynamic and rheological factors are important in the filter design, to minimize pore plugging and flow decay. Ancrod and batroxobin are thrombin-like enzymes which are purified from pit viper venom, and are commercially available in Europe for their anticoagulant and rheological therapeutic effects. Intramuscular injection of lignocaine to normal subjects caused transient, small but significant decreases in plasma and blood viscosity, without change in hematocrit or red cell filtration.
