The purpose of this study is to determine whether the kinetics of endogenous albumin is altered by the generalized inflammation caused by major abdominal surgery.

Albumin infusions have been used for expansion of the plasma volume for more than 60 years, not only in the operating room, but also in trauma and sepsis. However, there is an ongoing debate whether albumin is good or bad for the patient compared to other intravenous fluids, in different situations. Our research program aims at exploring this issue, starting by describing how the body handles the endogenous albumin in connection with severe inflammation. The final goal is to improve fluid treatment for these patients.

Plasma albumin is often decreased in inflammation. However, the underlying mechanisms are not well described. Two aspects of albumin kinetics will be covered in this study by measurements immediately before and two days after major abdominal surgery, that will serve as a model for generalized inflammation. Albumin fractional synthesis rate will be determined by the incorporation of deuterium labelled phenylalanine into plasma albumin. Albumin distribution will be measured as transcapillary escape rate of radioiodinated albumin. By assessment of P-albumin and plasma volume it will be possible to calculate albumin absolute rate of synthesis and albumin absolute flux from the central compartment, respectively.

Inclusion Criteria:

• written informed consent
• patients planned for major abdominal surgery, pancreatic
• age ≥ 40 years

Exclusion Criteria:

• pregnant or lactating patients
• planned peri-operative infusions of albumin or plasma
• S-creatinine > 110 mmol/L
• allergy against iodine
• other conditions preventing the subject from participating in the study, as judged by the investigator