The blood compatibility of the polymethoxyethyle acrylate (PMEA) coated and uncoated hollow fibers were investigated using multivariate statistical methods. The patients were divided into two groups where one is PMEA-coated fibers used patients and the other is uncoated oxygenator fibers used patients. The two groups were evaluated by total bilirubin, direct bilirubin, erythrocyte, albumin, fibrinogen, leukocyte, and total protein analysis results. Three evaluations were taken for comparison: baseline (T1), after protamine injection (T4) and intensive care (T5). There are no significant differences in the comparison. Additionally, the measurements were also compared by age. The patients were divided to four different age groups and no differences were found between the age groups except intensive care fibrinogen value and baseline protrombine time (Pt) Value. Then attempt were made to look for the significant correlation value of the measurements. After significant one was found, one measurement value was taken as dependent variable and the measurements, which are highly correlated with dependent variable as independent variables in the regression model. All of the models established that the analysis were significant with both squared r, p and F values. In some regression models, only interaction effect was seen with the variables, which means that PMEA-coating created more hydrophilic surfaces for protein adsorption when compared with uncoated Cardiopulmonary by pass filters.