Effect of cardiopulmonary bypass on plasma fibronectin, IgG, and C3

The effect of cardiopulmonary bypass operations on the concentration of plasma fibronectin, IgG, and C3 was studied in 28 patients. During cardiopulmonary bypass operations, plasma IgG, and C3 decreased to about 45 percent of their preoperative concentrations, probably as a result of hemodilution and blood loss. On the average, plasma fibronectin decreased significantly more (p less than 0.002), to 32 percent of its preoperative concentration, probably as a result of hemodilution, blood loss, and consumption. We assumed that consumption of fibronectin occurred when its concentration decreased more than the concentrations of IgG and C3. Interestingly, consumption of fibronectin during bypass operations was not demonstrated in seven of the 28 patients who did not require blood products within the 24-hour period after operation. We suggest that consumption, rather than dilution, of plasma fibronectin might be clinically important. A significant (p less than 0.002) negative correlation was observed between the length of the bypass and the concentration of plasma fibronectin during this 24-hour period. We also studied the rate of regeneration of fibronectin, IgG, and C3 in 12 of these patients. The concentrations of fibronectin and C3 were normal by the fifth postoperative day. The rate of regeneration of IgG, however, was slower than that of fibronectin and C3.