Objectives: To show the amount of perioperative blood loss and the relationship with monitored risk factors in patients undergoing planned surgery at the Department of Cardiac Surgery, and then treated in the Cardiac Surgical Intensive Care Unit of the Department of Anaesthesiology, Reanimation and Intensive Care (University Hospital of Split) in the period from the beginning of October to the end of December in 2023. Subjects and methods: 88 elective cardiac surgery patients were included in the study. The primary outcome measure of this study is the amount of total drainage after cardiac surgery and its association with monitored risk factors. Secondary outcome measures are the number of days of stay in the intesive care unit (ICU) and the duration of mechanical ventilation. Results: During the individual comparison of surgical procedures and the amount of total drainage, there was a statistically significant difference in the amount of total drainage (p = 0.024) between combinied surgery (coronary artery bypass grafting and valve replacement) and valve replacement surgery, where the median of total drainge was 1057.5 ml in combined surgery versus 470 ml median in the valve replacement surgery. A statistically significant positive influence between the duration of surgery and the amount of total drainage was demonstrated (p = 0.024), however, a statistically significant influence of the duration of extracorporeal circulation on the amount of total drainage was not demonstrated (p = 0.252). A statistically significant positive influence was demonstrated between the duration of the clamped aorta and the amount of total drainage (p = 0.001). No statistically significant influence of age (p = 0.358) and body mass index (BMI) (0.967) on the amount of total drainage was observed. A significant influence of the amount of total drainage on the duration of mechanical ventilation (p = 0.001) and on the number of days of stay in the ICU (p = 0.005) was demonstrated. Conclusions: In this retrospective study, a longer operation duration shows a significant influence on the amount of total drainage, but not on the duration of ECC. Long-term cross-clamping of the aorta shows a significant influence on the amount of total drainage. A greater amount of total drainage has been demonstrated when performing combined surgery versus valve replacement surgery. In this retrospective study, no significant influence of age and BMI on the amount of total drainage was demonstrated. A larger total amount of drainage is significantly associated with longer ICU stay and longer duration of mechanical ventilation.