Reduced White Blood Cell Microrheology and Postoperative Complications Associated with Cardiopulmonary Bypass

The effect of cardiopulmonary bypass (CPB) trauma and damage to the white blood cells (WBC) was prospectively studied in relation to myocardial microcirculation and postoperative complications in 45 patients undergoing cor onary bypass operations for angina pectoris. The filtrability of a suspension of white cells in plasma (P-WFR) was analyzed during CPB and in the first week following coronary bypass operations for angina pectoris. The damage to white cells due to CPB reduced filtrability by about 40% (p < 0.05) and a reduced filtrability was noted even one week after successful surgery. In 25 patients the microflow in the myocardium was semiquantitatively assessed intraoperatively by laser Doppler flowmetry (LDF%), and there was a positive correlation be tween P-WFR and LDF% (r=0.84, p < 0.01). The most common complication requiring treatment was cardiac arrhythmias (atrial fibrillation or flutter 12/45, 27%). Myocardial infarction, 9%; A-V blocks, 4%; respiratory insuffi ciency, 4%; cerebrovascular accident, 2%, and infections, 4% were also noted. The trauma to the WBC during CPB appears to reduce myocardial microflow and could be a factor in triggering postoperative complications. Studies to pro tect the WBC or remove damaged WBC during and even after CPB would appear to be warranted.