Effects of theophylline on renal function in premature infants

摘要: Xanthines are frequently being used in the management of premature babies. Studies adult subjects have demonstrated a diuretic effect aminophylline due to inhibition solute reabsorption various segments nephron. We evaluated effects on developing kidney. Nineteen infants, with mean +/- SD gestational age 31.1 2.8 weeks and birth weight 1481 454 g were studied at 4.5 4.0 days before after 20-minute loading infusion 6 mg/kg aminophylline, followed by maintenance therapy dose 2 every 12 hours. A marked diuresis occurred immediately dose, ratio urinary output water intake increased from 0.58 0.36 1.19 0.65. Concomitantly, fractional excretion sodium 2.7 2.6% 5.7 4.4% that potassium rose 21 19% 31 21%. Urinary calcium uric acid also enhanced: creatinine 0.31 0.29 0.60 0.54 2.5 1.5 3.8 2.0. Tubular phosphorus (TRP) was not affected. Most no longer evident 24 hours, despite continuing therapy. In infants but therapy, affected renal functions. Because heart rate, blood pressure, clearance did change, it appears acts directly tubular reabsorptive