[Pharmacokinetics and clinical evaluation of aztreonam in pediatric surgery]

Pharmacokinetic and clinical studies on aztreonam (AZT) in pediatric surgery were performed and results obtained are summarized below. 1. Plasma and urinary levels of AZT were measured in 6 neonate patients following drip-infusion for 1 hour of AZT (dose of AZT: 20 mg/kg). Plasma levels reached their peak (42.3-50.4 micrograms/ml) at the end of infusion or in 1 hour thereafter except in case 2. In case 2, plasma level reached its peak (36.6 micrograms/ml) at 2 hours after the end of infusion. Plasma levels of AZT decreased rapidly after reaching their peaks, and plasma half-lives (T 1/2) were 1.85-2.84 hours. Urinary recovery rates were 15.7-65.3%. 2. Bile levels of AZT were determined in 8 patients with biliary atresia following 1 hour drip-infusion of AZT (dose of AZT: 20 mg/kg for 4 patients, 40 mg/kg for the other 4 patients). In the 20 mg/kg group, peak levels of AZT in bile were noted 2 hours after the end of infusion, and they were 3.7-7.1 micrograms/ml. Recovery rates in bile in the first 6 hours after the end of infusion were 0.34-0.9%. In the 40 mg/kg group, peak levels of AZT in bile were found at 2 hours and 2-4 hours after the end of infusion, and they were 4.9-8.8 micrograms/ml. Recovery rates in bile in the first 6 hours after the end of infusion were 0.03-0.33%. 3. AZT and ampicillin were administered to 6 patients as prophylaxis against postoperative infections. Another patient with postoperative cholangitis was given AZT alone.(ABSTRACT TRUNCATED AT 250 WORDS)