HYPERSTIMULATION OF LEUKOCYTES BY PLASMA FROM CARDIOPULMONARY BYPASS PATIENTS IS DIMINISHED BY MORPHINE ANA IL-10 PRETREATMENT

Objective. The trauma of cardiopulmonary by-pass (CPB) in cardiac surg ery results in a whole body diffuse inflammatory response characterize d in part by hyperstimulation of leukocytes. Partially this is due to an increase in the release of biological response modifiers such cytok ines, as noted by the immunocyte stimulatory actions of cell-free plas ma obtained postoperatively from CPB patients. The present study was c onducted to determine whether CPB plasma induced immunocyte hyperstimu lation can be prevented with naturally occurring immune inhibitory sub stances, specifically, interleukin (IL)-10 and/or morphine. Experiment al design. Controlled in vitro study of the application of drugs to na ive immunocytes to block the exitation caused by CPB-plasma. Setting. University-based tertiary care hospital. Patients. Plasma was obtained from ten patients undergoing CPB. Eligibility included admission for elective cardiac surgery, which no chronic illnesses or acute processe s. Interventions. Monocytes and granulocytes were pretreated with IL-1 0 and/or morphine before exposure to plasma obtained from patients und ergoing CPB, as CPB-plasma would stimulate naive monocytes and granulo cytes in a manner similar to that previously reported in CPB-patients. Measures. Computer-assisted microscopic image analysis, measuring cel lular conformational and velocity changes, was used to evaluate the ef fect of treatment on the immunocytes response to stimulation with CPB- plasma. Results. Pretreatment of cells with IL-10 and/or morphine sign ificantly diminished the hyperstimulation induced by CPB-plasma in a c oncentration-dependent manner. In contrast, when the cells were initia lly or simultaneously exposed to CPB-plasma, IL-10 and/or morphine had no effect. Conclusions. Taken together, the data strongly suggest tha t naturally occurring immune inhibitory substances can diminish the im munocyte hyperstimulation associate with CPB-plasma exposure. Thus, si nce the body's own defense mechanisms appear to exacerbate the trauma of cardiac surgery, prophylactic use of these substances may enable pa tients to recover at a faster rate.