Membrane bioincompatibility was demonstrated by successive white blood cell counts and C3a generation. Pulse wave analysis was obtained by applanation tonometry (SphygmoCor) in a sequential way: basal, after 30 minutes with nul ultrafiltration, and after a complete dialysis with ultrafiltration. At 15 minutes of haemodialysis, significant decrease in leukocyte count occurred: 6801 ± 1186 versus 4412 ± 1333 (P < 0.001), while C3a levels sharply increased from 427 ± 269 to 3501 ± 1638 ng/mL (P < 0.000). No changes were observed in augmentation index without ultrafiltration: 26.1 ± 11.1 versus 26.6 ± 12.4. Only aortic systolic blood pressure was lower at 15 minutes: 120.1 ± 17.7 versus 110.4 ± 25.8 mmHg (P = 0.009), in agreement with a reduction in brachial systolic blood pressure: 135.1 ± 18.1 versus 122.7 ± 27.4 mmHg (P = 0.01), without changes in aortic or brachial diastolic blood pressure. Important changes in pulse wave analysis were observed after a complete haemodialysis session: augmentation index 29.9 ± 10.1 versus 18.6 ± 15.0, aortic systolic blood pressure 139.8 ± 25.5 versus 119.4 ± 28.5 mmHg (P < 0.00), without changes in aortic diastolic blood pressure. In summary, haemodialysis with cellulose diacetate acutely induced a transient state of immunoactivation due to bioincompatibility, this phenomenon was nondetectable by pulse wave analysis. Complete haemodialysis session led to important changes in pulse wave analysis.