Plasma vasopressin response to contrast medium during cardiac catheterization in infants and children.

Fifteen infants and children (M = 7, F = 8), aged from 0 to 13 years, who underwent cardiac catheterization and cardioangiography under ketamine-diazepam anesthesia were the subjects of this study. The effect of a contrast medium, isolamate sodium (66.8%) on the plasma somolality and vasopressin concentration was studied. The plasma osmolality was significantly elevated after contrast medium administration (289 +/- 3 vs. 303 +/- 8 mosmol.kg(-1)) as well as plasma vasopressin (from 2.1 +/- 0.9 vs. 4.7 +/- 2.0 micro-unit.ml(-1)). It is concluded that the administration of contrast medium for cardioangiography causes elevation of plasma osmolality, which leads to the elevation of plasma vasopressin concentration.