Objective:7o test the hypothesis that patients with acute normovolaemic haemodilution (ANH) tolerate better aortic clamping and declamping during abdominal aortic aneurysm (AAA) repair. Perioperative haemo-dynamic changes are mitigated, thus the frequency of ischaemic events and cardiovascular complications are decreased in comparison with the group of patients without ANH. Design: Prospective randomized study. Setting: Department of Anesthesiology, Resuscitation and Intensive Medicine, University Hospital. Materials and methods: 50 patients admitted for elective AAA repair were prospectively randomized into two groups: patients in group A (n = 25) were treated with ANH and patients in group B (n = 25) were not. We monitored the following parameters: BP, MAP, HR, SV, CO, CI,TSVR (HemoSonic™100, 400 measure-ments), troponin I level, transfusion requirements and 30-day mortality. Statistical analysis was made using Wilcoxons rank sum test, Mann-Whitney test and Fisher test. Results: After aortic clamping a statistically significant increase in the systolic BP and TSVR, and a decrea-se in SV, CO and Cl occurred in both groups (p < 0.05). After aortic declamping, a statistically significant decrease in TSVR and the systolic, diastolic and mean BP, and an increase in SV, CO, Cl were seen in both groups (p < 0.05). A statistically significant difference between the two groups was evident in Cl after aortic clamping and the systolic and mean BP before declamping. Ischaemic myocardial injury was seen 6 times in patients with ANH vs. 8 times in patients without ANH. A statistically significant difference was not manifested. Conclusion: We did not demonstrate a statistically significant difference in haemodynamic changes, the frequency of perioperative or postoperative complications, and ischaemic events between two groups of patients treated with and without ANH.

        Key words: abdominal aortic aneurysm - acute normovolaemic haemodilution - haemodynamic parameters - transesophageal doppler - troponin I