Stability of fentanyl citrate and bupivacaine hydrochloride in portable pump reservoirs.

The stability of fentanyl citrate and bupivacaine hydrochloride in an admixture with 0.9% sodium chloride injection in portable pump reservoirs with or without overwraps was investigated. Twelve 100-mL samples containing fentanyl 20 micrograms/mL and bupivacaine hydrochloride 1250 micrograms/mL were placed in the plastic drug reservoirs, and 1-mL quantities were withdrawn immediately after preparation and at intervals during 30 days of storage. Six reservoirs were refrigerated (3 degrees C) and six stored at room temperature (23 degrees C); three at each temperature were placed in overwraps. All samples were observed for precipitation and for change in color or pH and were analyzed for drug concentration by high-performance liquid chromatography. No precipitation or change in color or pH was observed during the 30-day storage period. No loss of fentanyl or bupivacaine was detected in either the wrapped or the unwrapped samples. Fentanyl citrate and bupivacaine hydrochloride in 0.9% sodium chloride injection appear to be compatible, and admixtures containing the two drugs at the concentrations studied can be stored without overwraps for up to 30 days at refrigerated or room temperature without any significant loss of potency.