title: Cefazolin and netilmicin serum levels during and after cardiac surgery with cardiopulmonary bypass.
abstract: The kinetics of cefazolin and netilmicin were studied in 10 patients undergoing elective cardiac surgery with hemodilution and cardiopulmonary bypass (CPB). During surgery, but before CPB, cefazolin, 25 mg/kg, and netilmicin, 2 mg/kg, were administered intravenously over 30 minutes. For the 48-hour period following CPB, cefazolin, 25 mg/kg, and netilmicin, 1 mg/kg, were administered intravenously every 8 hours. Initiation of CPB was accompanied by a 28% to 30% decrease in hematocrit and serum antibiotic levels. At the conclusion of surgery, cefazolin and netilmicin serum levels were 41 +/- 12 micrograms/L and 2.5 +/- 0.6 micrograms/mL (mean +/- SD), respectively. During the postoperative period, cefazolin levels were consistently greater than the minimum inhibitory concentration (MIC) for sensitive bacteria (4 micrograms/mL); average netilmicin levels were greater than MIC of sensitive bacteria (2 micrograms/mL) for 2 hours after antibiotic infusion. The netilmicin trough levels were 0.6 +/- 0.5 micrograms/mL. Pharmacokinetic parameters were determined using a model-independent method, and gave the following results during surgery: cefazolin--elimination half-life, 231 minutes, total body clearance, 1.05 mL/kg/min, and steady-state volume of distribution, 243 mL/kg. The values for netilmicin were 249 minutes, 1.18 mL/kg/min, and 353 mL/kg, respectively. Postoperatively there were no significant changes in the disposition of cefazolin, but the elimination half-life of netilmicin was shorter (124 minutes, P less than 0.01) and the total body clearance greater (3.58 mL/kg/min, P less than 0.01) than during surgery.
authors: Département d'Anesthésie Réanimation, Hôpital Cardiovasculaire Louis Pradel, Lyon, France.
authors: J J
authors: JJ
authors: Lehot
authors: M E
authors: ME
authors: Reverdy
authors: J
authors: J
authors: Etienne
authors: C
authors: C
authors: Corot
authors: C
authors: C
authors: Nervi
authors: J
authors: J
authors: Sear
authors: J
authors: J
authors: Fleurette
authors: S
authors: S
authors: Estanove
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D002437:Cefazolin / Q000097:blood* / Q000493:pharmacokinetics / Q000627:therapeutic use; D005260:Female; D006207:Half-Life; D006400:Hematocrit; D006801:Humans; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D009428:Netilmicin / Q000097:blood* / Q000493:pharmacokinetics / Q000627:therapeutic use; D011182:Postoperative Care; D011292:Premedication; D013997:Time Factors
chemical_list: D009428:Netilmicin; D002437:Cefazolin