Stability of an epidural analgesic admixture of levobupivacaine, fentanyl and epinephrine.

WHAT IS KNOWN AND OBJECTIVE

Admixtures of levobupivacaine, fentanyl and epinephrine are increasingly used in epidural pain management. Neither the compatibility nor the stability of levobupivacaine with fentanyl and epinephrine is known and therefore we examined the chemical, physical and microbiological stability of levobupivacaine-fentanyl-epinephrine and levobupivacaine-fentanyl admixtures prepared in the hospital pharmacy.

METHODS

Fentanyl and epinephrine were added into commercial levobupivacaine infusion bags. The components were analysed by HPLC and assays were performed up to 60 days of storage of the bags both protected and exposed to light at room temperature and stored in the refrigerator. In addition, sterility, bacterial endotoxins, organoleptic properties, pH and mass of the admixture were determined.

RESULTS AND DISCUSSION

Levobupivacaine, fentanyl and epinephrine concentrations remained within the ± 10% specification limit during 60 days storage in the refrigerator in tightly closed secondary packing material and protected from light and for at least 40 days at room temperature. The degradation of epinephrine exceeded 10% within 60 hours when exposed to light. The solutions were microbiologically and physically stable.

WHAT IS NEW AND CONCLUSION

Epidural analgesic admixtures of levobupivacaine and fentanyl with or without epinephrine have to be stored in a tightly closed secondary package protected from light. The extended stability, up to 60 days, in a refrigerator enables the centralized preparation in the hospital pharmacy.