To evaluate the change of perioperative cell mediated immunity after cardiac operation with cardiopul-monary bypass （CPB）

so as to provide some information for timely prevention and treatment against post-operative immunological disorder

40 patients were studied. By searching for the effects of CPB and anes-thesia

interleukln-2 receptor （IL-2R） expression upon the surface of peripheral blood mononuclear cells（PBMC）

as well as interleukin-2 （IL-2） production in vitro was traced 55 min after anesthesia

at end ofCPB

on postoperative 1

7

and 14 day versus preanesthesia control. Our data demonstrated that expres-sion of IL-2R on PBMC was significantly suppressed in all comparing with the baseline value

meanwhile

IL-2 production in vitro also statistically dropped. However

no statistical difference was found on perioper-ative IL 2R expression and IL-2 synthesis in the cholecystectomy group. We conclude that postoperativeimmunological disorder seems to be the main factor

which could be denoted as reduced IL 2R expressionon PBMC and lL-2 synthesis in vitro for sepsis

even multiple system organ failure developed after cardiacsurgery.