Investigation into spinal anesthetic failure with hyperbaric bupivacaine: the role of cold exposure on bupivacaine degradation

Purpose Hyperbaric bupivacaine (0.75% in dextrose) is used for spinal obstetric anesthesia. Occasional clusters of anesthetic failures occur in this setting, not readily attributable to clinical factors. We hypothesized that cold temperature exposure is related to bupivacaine instability.