Treatment with colloidal solutions has during long time been a cornerstone within intensive care. Lately there has been a shift from synthetic colloids to natural albumine.

One of these solutions is the hyperoncotic "Albumin 20%". There are however still several aspects of the physiological effects of hyperoncotic albumin, that are not known.

In this study the main object is to study with what rate hyperoncotic albumin should be administered. Rapidly 30 minutes or slower 120 minutes.

Difference in volume expansion as well as fluid recruitment from the tissues depending on infusion rate is of interest.

Plasma volume expansion is measured using hemoglobin as a marker and fluid recruitment of tissue fluid is measured as a combination of plasma volume expansion and urinary output.

Healthy individuals are asked to refrain from eating and drinking the night before the study. Two hours before study start, the subjects may take a sandwich and a glas to drink.

After 15 minutes of rest baseline blood samples are taken. Subjects are randomised to receive two rates of albumin solution (Albumin 20%) 3 ml/kg bodyweight at two separate occasions. Once with an infusion time of 30 minutes, once with an infusion time of 120 minutes. Between the two infusions there will be an interval of 3 to 20 weeks. Randomization is performed to chose which rate the subjects start with. 6 in each Group (total 12).

During each occasion15 blood samples are collected, during a 6 hour period. Hemoglobin, plasma Sodium, colloid osmotic pressure and albumin are analysed. The total volume of blood collected will be 170 ml at each occasion when an albumin infusion is given.

Urinary output is measured and Urinary Sodium content is measured. Liberal fluid intake is recommended the same day and the next.

Inclusion Criteria:

- Healthy, without allergies and with the age 18 years or above

Exclusion Criteria:

• Heart failure
• Signs of kidney injury/failure
• Severe allergies
• Pregnancy