The effect of contrast media on immature renal function. Comparison of agents with high and low osmolality.

Abstract

Contrast media having high osmolality (methylglucamine diatrizoate; 1510 mOsm/kg) and low osmolality (triiodoisophthaldiamide, 616 mOsm/kg) were compared in 15 functionally immature rabbits 2-3 wk of age. Renal function was assessed with a gamma camera and whole-body counter, using excretion of 99mTc-Sn-DTPA [diethylenetriaminepentaacetic acid] as an index of glomerular filtration rate. Both DTPA and the contrast agent (2 ml/kg) were injected as a single i.v. bolus in 15 s. After 40 min, percent DTPA excreted was 33.0 .+-. 2.3 for triiodoisophthaldiamide and 28.2 .+-. 1.5 (P < 0.01) for methylglucamine diatrizoate. Excretion of DTPA was reduced with the latter (P < 0.005) but not the former agent (P > 0.6). Contrast materials with high osmolality depress renal function in immature rabbits, suggesting that agents with low osmolality are preferable for use in newborns.