Stability of ceftazidime and vancomycin alone and in combination in heparinized and nonheparinized peritoneal dialysis solution.

OBJECTIVE

To examine the stability of ceftazidime, vancomycin, and heparin, alone and in combination, in dialysis solution over six days at three temperatures.

DESIGN

Nine 250-mL Dianeal PD-2 dextrose 1.5% bags were prepared with ceftazidime, vancomycin, and heparin alone and in combination at set concentrations of 100 micrograms/mL, 50 micrograms/mL, and 1 unit/mL, respectively. Three bags of each mixture were stored at 4, 25, and 37 degrees C. Duplicate samples for analysis were removed from each bag at the following time points: premix, 0, 12, 24, 48, 72, 96, 120, and 144 hours.

MAIN OUTCOME MEASURES

Each sample was examined visually for signs of cloudiness and precipitation. Each sample was analyzed by stability-indicating HPLC assay for ceftazidime and vancomycin, with stability defined as less than 10 percent degradation of drug over time.

RESULTS

No color change or precipitation was observed in any bag. Vancomycin with or without heparin was stable for 5-6 days at 4, 25, and 37 degrees C. Ceftazidime with and without heparin was stable for 6 days at 4 degrees C, 4 days at 25 degrees C, and less than 12 hours at 37 degrees C. Vancomycin plus ceftazidime with and without heparin was stable for 6 days at 4 degrees C and 25 degrees C, and 4-5 days at 37 degrees C. Ceftazidime plus vancomycin with or without heparin was stable for 6 days at 4 degrees C, 2-3 days at 25 degrees C, and 12 hours at 37 degrees C.

CONCLUSIONS

Bulk preparations of ceftazidime and vancomycin, alone and in combination and with or without heparin in Dianeal PD dextrose 1.5% solution, are sufficiently stable for use up to 6 days under refrigeration or 48 hours at room temperature.