Extracorporeal circulation, cardiopulmonary bypass, and ECMO device are indispensable components in the work process and heart an/or lung operations, in prolonging life in patients at end-stage heart decompensation or pulmonary insufficiency, in polytrauma or in children with cardiovascular birth defects. They are the gold standard in open heart surgery and not beating heart surgery in a state of cardioplegia. Also, in patients where it is expected and there is a possibility of mass bleeding, the device has cooled blood circulation and ultimately body hypothermia. The aim of the paper was to demonstrate the importance of nurse competencies and the ability to work with this device in the cardiac surgeon's and thoracic surgeon's teams and to present the crown difficulty of nursing work. The ecamination was conducted on the students of first, second and third year of undergraduate study of nursing at the Faculty of Health Studies of the University of Rijeka. The goal of the questionnaire survey in which the quantitative analysis was conducted was aimed at comparing th knowledge of the students of the first year of study and the third year of the study assuming that the studnets of the third year of study have more knowledge of the history, methods of work and role of the extracorporeal circulation device. The total number of respondents for all three years of the study was 62. the most significant results that deviated from the average were related to the answers and knowledge about this type of support in cardiothoracic surgery or traumatology. The questionnaire was conducted with an online survey that contained 20 questions. Questions were conceived as closed, and to a number of questions, answers ere given with a scale of numbers ranging from 1 to 5.