Vancomycin pharmacokinetics in critically ill patients.

Peak and trough vancomycin serum levels were measured in 37 severely ill patients following dosing using the Moellering nomogram. The peak and trough serum concentrations were 61.2 +/- 23 and 22.6 +/- 16.5 mg/l, respectively, and higher than expected. Vancomycin pharmacokinetics obtained from 10 other patients were also studied. In five patients with a creatinine clearance greater than 1 ml min-1 kg-1, a mean plasma elimination half-life of 7.8 +/- 2.8 h was calculated. In the five other patients with markedly reduced renal function (creatinine clearance less than or equal to 1 ml min-1 kg-1), the mean elimination half-life was 18.3 +/- 10.2 h. A correlation was observed between the vancomycin and creatinine clearance. Important inter-patient variations of vancomycin clearance for the same creatinine clearance was also noted. Tubular damage in critically ill patients with severe sepsis may explain our results of the decreased vancomycin elimination.