[Determination of plasma atrial natriuretic peptide in follow-up of hypervolemic hemodilution in patients with retinal circulatory disorders].

We measured plasma levels of atrial natriuretic peptide (ANP) in 20 patients with impaired retinal circulation in order to monitor hypervolemic hemodilution. In 18 control subjects, plasma ANP levels averaged 37.4 +/- 7.3 pg/ml and 30.0 +/- 5.4 pg/ml before and after an i.v. infusion of 250 ml of HAES 6% over 3 hours. In 8 of 20 patients, plasma ANP exceeded the highest value of 87 pg/ml in the controls at the end of the first infusion. In the group B, ANP increased from 103 +/- 21.6 pg/ml to 142 +/- 12 pg/ml before and after the infusion. In the remaining 12 patients (group A), plasma levels of ANP were 41.1 +/- 8.6 and 44.8 +/- 6.3 pg/ml at the start and the end of the first infusion of HAES. All patients received 500 ml of HAES daily for 8 days. In group B, hemoglobin was significantly lower on day 8 (11.7 +/- 0.48 versus 13.2 +/- 0.38 mg/100 ml) compared to group A (p less than 0.005). Similarly, hematocrit and serum protein was reduced to a greater extent in group B compared to group A indicating intravascular volume expansion. Measuring plasma ANP-levels might be of value to identify patients with reduced tolerance to hemodilution therapy.