Anesthesia, formed elements of the blood, and macrophages.

Anesthetics depress not only compact organs such as the brain and heart but also the diffuse array of single cells that comprise the formed elements of the blood and macrophages of the reticuloendothelial system (RES). The principal anesthetic effect is depression of contractile elements of these cells subserving the functions of phagocytosis, cell locomotion, and transvascular diapedesis. Marrow granulocyte production and in vitro lymphocyte transformation are also depressed. Effects on erythrocytes are limited to the membrane, which anesthetics render somewhat resistant to rupture. These anesthetic actions are of interest both to basic scientists concerned with structure and function of single cells and to clinicians caring for patients whose circulating and fixed formed elements are dysfunctional.