STEROID INHIBITION OF CYTOKINE-MEDIATED VASODILATION AFTER WARM HEART-SURGERY

Background Peripheral vasodilation, a potentially adverse effect of wa rm heart surgery, may be mediated by the perioperative release of cyto kines. Corticosteroids may abolish cytokine production and vasodilatio n. We investigated cytokine production and its inhibition by steroids in patients undergoing elective coronary bypass surgery. Methods and R esults Twenty-five patients undergoing coronary bypass surgery with no rmothermic cardiopulmonary bypass received either preoperative steroid (Solumedrol 250 mg IV, n=16) or no steroid (n=9, control group). Bloo d samples were obtained serially for 24 hours and assayed for interleu kin-6 (IL-6), tumor necrosis factor (TNF), and interleukin-8 (IL-8). I n the control patients, the IL-6, TNF, and IL-8 levels were elevated p ostoperatively and peaked between 3 and 6 hours after surgery (IL-6, 1 330+/-295 [mean+/-SEM] pg/mL; TNF, 18.4+/-9.8 pg/mL; and IL-S, 150+/-5 1 pg/mL). Cytokine release was abolished in patients receiving preoper ative corticosteroid (IL-6, 75+/-38 pg/mL; TNF, 2.6+/-0.5 pg/mL; and I L-8, 33+/-6.7 pg/mL; P<.05). Patients receiving steroid premedication had higher arterial pressure, lower cardiac index, and higher systemic vascular resistance, indicating less vasodilation. Conclusions Our fi ndings demonstrate that cytokine production occurs after normothermic cardiopulmonary bypass. Preoperative administration of steroids abolis hes cytokine release and vasodilation.