ORTHOSTATISM TEST

Purpose

To investigate mineralocorticoid function when standing up.

Subject preparation

Fasting for 12 hours.

Protocol

1 Either a first sample (EDTA tube) taken with the patient lying down and a second (EDTA tube) after one hour of walking.

2 Or a first sample taken after one hour of walking and a second after two hours lying down.

Samples

After centrifugation at room temperature, draw off the plasma and freeze as soon as possible.

Assays

Aldosterone and active renin.