title: Chronic neurological deficits and Nesacaine-CE--an effect of the anesthetic, 2-chloroprocaine, or the antioxidant, sodium bisulfite?
abstract: Chronic neurological deficits have been described in patients after presumed accidental subarachnoid injection of 2-chloroprocaine-CE (Nesacaine-CE; N-CE) intended for epidural block. This study investigated the possible role of pure 2-chloroprocaine (2-CP) and sodium bisulfite, two components of Nesacaine-CE, in causing these complications when injected separately into the lumbar subarachnoid space of neurologically intact awake rabbits. Repeated 2-4-mg spinal anesthetic doses of pure 2-CP in lactated Ringer's solution did not produce chronic hindlimb paralysis even though accumulated doses reached 50 mg. However, 1.2-2.4 mg of sodium bisulfite, the antioxidant in N-CE added to prolong shelf-life, resulted in irreversible hindlimb paralysis in 12 out of 14 animals. This amount of bisulfite is contained in 12-24 mg of 2% N-CE. The demonstration that persistent paralysis resulted from low dosages of sodium bisulfite contained in commercially available 2-CP requires reevaluation of the suitability of this antioxidant for products prepared for intrathecal use.
mesh_terms: D000779:Anesthetics, Local / Q000008:administration & dosage / Q000009:adverse effects*; D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage / Q000009:adverse effects*; D006614:Hindlimb; D010243:Paralysis / Q000139:chemically induced* / Q000473:pathology; D011343:Procaine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D011817:Rabbits; D013447:Sulfites / Q000008:administration & dosage / Q000009:adverse effects*
chemical_list: D000779:Anesthetics, Local; D000975:Antioxidants; D013447:Sulfites; D011343:Procaine; C004616:chloroprocaine; C009279:sodium bisulfite