Effects of autologous blood withdrawal-reinfusion on inflammatory responses of patients undergoing cardiac surgery with different time courses of cardiopulmonary bypass

Objective To evaluate the effects of autologous blood withdrawal-reinfusion on inflammatory responses of patients undergoing cardiac surgery with different time courses of cardiopulmonary bypass (CPB). Methods A total of 120 patients, aged 18-70 yr, of American Society of Anesthesiologists physical status Ⅱ-Ⅳ, were divided into 2 groups (n=60 each) using a random number table: autologous blood withdrawal-reinfusion group (ABWR group) and non-autologous blood withdrawal-reinfusion group (NABWR group). Each group was further divided into 3 subgroups (n=20 each) according to the expected time of CPB: long time course (>120 min) subgroup (L subgroup), medium time course (>60 min-≤120 min) subgroup (M subgroup) and short time course (≤60 min) subgroup (S subgroup). In group ABWR, after the end of CPB and after heparin was reversed with protamine, blood shed from the surgical field and left in the autologous blood recycling machine pipeline after the end of CPB was collected, filtrated, washed, concentrated and reinfused.After the end of CPB, blood left in the autologous blood recycling machine pipeline was directly kept in the storage bag and partially or totally reinfused in group NABWR.Before operation and at 1, 6, 24 and 48 h after the end of CPB, blood samples were collected for determination of serum tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and IL-10 concentrations by enzyme-linked immunosorbent assay. Results Compared with ABWR-S subgroup, the serum TNF-α and IL-6 concentrations were significantly increased at each time point after the end of CPB (P 0.05). There were no significant differences in serum TNF-α, IL-6 and IL-10 concentrations between ABWR-L subgroup and ABWR-M subgroup (P>0.05). Compared with NABWR subgroup of the same time course, the serum TNF-α concentration was significantly decreased at each time point after the end of CPB, the serum IL-6 concentration was decreased at 6-48 h after the end of CPB (P 0.05); the serum TNF-α concentration was significantly decreased at 1 h after the end of CPB, and the serum IL-6 concentration was decreased at 6 and 24 h after the end of CPB in ABWR-M subgroup (P<0.05); no significant difference was found in the serum concentrations of TNF-α, IL-6 or IL-10 at each time point after the end of CDB in ABWR-S subgroup (P<0.05). Conclusion With prolongation of the time courses of CPB, the efficacy of autologous blood withdrawal-reinfusion in inhibiting inflammatory responses of patients undergoing cardiac surgery is more significant. Key words: Blood transfusion, autologous; Cardiopulmonary bypass; Cardiac surgical procedures; Systemic inflammatory response syndrome