Hypotension with potentially serious consequences for organ perfusion is a common complication in extracorporeal procedures such as hemodialysis / hemofiltration. The exact reasons for this are still insufficiently clarified. Probably periinterventional vasorelaxant released substances play a crucial role in these procedures. These substances could be due to contact of blood cells with the Membrane in the dialyzer / hemofilter arise. In this project the hypothesis will be checked, if EETs / DHETs are released by Erythrocytes during hemodialysis and thus act as potential candidate products for the result of hypotonic phases in the Dialysis.

We will determine differences in RBC fatty acids profiling in hemodialysis patients before and after dialysis intervention. Furthermore a matched control group of healthy individuals will be profiled. RBC fatty acids profiling will be achieved by using targeted HPLC-MS mass spectrometry.

It is believed that during hemodialysis / HLM / CVVH there is an increase in EETs / DHETs in the serum and in the erythrocytes. It is believed that shear forces play an important role in the release of erythrocyte EETs / DHETs.

Differences in Erythrocyte Fatty-Acid Status Profiling in:

• before and after hemodialysis intervention
• in hemodialysis patients and healthy individuals Venous blood will be collected from each subject in the sitting position

Inclusion Criteria for hemodialysis patients:

• Patients who have a history of renal failure and undergo hemodialysis / hemofiltration
• Age over 18 years
• Ability to consent
• There is a written consent of the study participant

Exclusion Criteria for healthy control group:

• chronic illness requiring any medication
• pregnancy
• limitations regarding functioning in the hypoxic chamber
• inability to follow simple instructions relevant or severe abnormalities in medical history, physical examination