STABILITY OF CEFPIROME SULFATE IN THE PRESENCE OF COMMONLY USED INTENSIVE-CARE DRUGS DURING SIMULATED Y-SITE INJECTION

The stability of cefpirome sulfate during simulated Y-site injection w ith drugs commonly used in the intensive care unit was studied. Cefpir ome sulfate was constituted and diluted to 50 mg/mL with 0.9% sodium c hloride injection, 0.45% sodium chloride injection, 5% dextrose inject ion, and lactated Ringer's injection. Each cefpirome sulfate solution was mixed 1:1 (simulating Y-site injection) with amikacin 5.0 mg/mL (a s the sulfate salt), amphotericin B 0.1 mg/mL, cefazolin 10 mg/mL (as the sodium salt), clindamycin 12.0 mg/mL (as the phosphate ester), dex amethasone phosphate 4.0 mg/mL (as the sodium salt), dopamine hydrochl oride 0.8 mg/mL, epinephrine 0.1 mg/mL (as the hydrochoride salt), flu conazole 2.0 mg/mL, gentamicin 1.0 mg/mL (as the sulfate salt), and va ncomycin 5.0 mg/mL (as the hydrochloride salt). All the drug combinati ons were prepared in triplicate and maintained at 23 degrees C. The co mbinations were observed visually at intervals up to eight hours, pH w as measured, and samples were tested for drug concentration by high-pe rformance liquid chromatography. Cefpirome was stable in the presence of each of the secondary drugs throughout the study period. All the se condary drugs except amphotericin B were stable in the presence of cef pirome. There were no visual phenomena indicating incompatibility. Cha nges in pH were minimal. Cefpirome 50 mg/mL (as the sulfate salt) in f our different diluents was stable in the presence of each of 10 common ly used intensive care drugs for at least eight hours during simulated Y-site administration. Amphotericin B 0.1 mg/mL was not stable in the presence of cefpirome sulfate.