Effect of Neosaxitoxin On Epidural Anesthesia in Cats: A Promising Alternative To Conventional Anesthetics - Effect of Neosaxitoxin On Epidural Anesthesia in Cats: A Promising Alternative To Conventional Anesthetics - Open Access Pub

Neosaxitoxin (NeoSTX) is a specific high-affinity inhibitor of voltage-dependent sodium channels, which has shown excellent results as a local anesthetic in various pathologies and post-operative protocols, since it effect is long-lasting and have virtually no side effects.The aim of this study was to analyze the effect of NeoSTX as an epidural anesthetic in female cats, undergoing ovariohysterectomy, compared to Lidocaine in a randomized and double-blind study. Two groups of 11 female cats were randomly in the NeoSTX group and the lidocaine group. They were administered, respectively, a single dose of NeoSTX (0.5 μg / kg) or lidocaine (4 mg / kg, 2%) by epidural via. Using the UNESP-Botucatu pain assessment scale, which considers multiple behavioral and physiological factors, the epidural anesthetic effect of NeoSTX and lidocaine was evaluated, up to 240 min after the ovariohysterectomy procedure. NeoSTX no altered the peripheral blood pressure during the cut of uterine cervix, and generated lower values on the pain scale as compared to the lidocaine treatment. None of the cats anesthetized with NeoSTX required an extra dose of pain-relieving drugs (2 mg / kg of tramadol) during the first 150 min after surgery, whereas nine cats from the lidocaine group did need an extra dose of analgesic. NeoSTX is a powerful pain blocker, with a long-lasting anesthetic effect when administered by an epidural procedure. Therefore, NeoSTX emerges as a promising alternative to conventional anesthetics for the treatment of postoperative pain. DOI10.14302/issn.2578-8590.ipj-19-2623 Epidural anesthesia is a clinical procedure that aims to control pain during surgery and the postoperative period, in which a local anesthetic is administered into the epidural space, outside the meninges of the spinal cord, to desensitize the sensory nerve endings that innervate the abdominal wall and the sacral nerve. The most used technique in veterinary medicine of small animals is to administer a local anesthetic between the vertebrae L7 S1, being lidocaine and bupivacaine the most commonly used drugs. Besides, systemic analgesics such as fentanyl, morphine, tramadol and dissociative anesthetics as ketamine, or combinations of these have been used with different results in terms of their anesthetic effect and duration times 18. However, for lidocaine and bupivacaine the duration of their anesthetic effects does not exceed 2 hours, and when they are combined with opioids, although the effect was prolonged, multiple side effects have been described, such as pruritus, central nervous system