Abstract

Regional anesthesia is an important part of reptile medicine by providing analgesia and reducing general and systemic anesthesia requirements and adverse effects.^1,2 Case reports describe regional anesthesia for surgical procedures on reptile forelimbs.^3,4 A brachial plexus blockade technique is indicated to provide forelimb anesthesia for painful procedures. The authors developed a repeatable blind perineural brachial plexus blockade technique in eastern box turtle (Terrapene carolina carolina) cadavers;⁵ its application to live turtles requires investigation.

This study evaluated the novel blockade technique in six adult eastern box turtles. Lidocaine at 5, 10, and 20 mg/kg and a saline control (0.9% NaCl) were randomized with one-week washout periods. Attitude, heart rate, respiratory rate, and limb response were taken at baseline and reassessed every 10 minutes. One turtle had evidence of a successful brachial plexus block at 10 and 20 mg/kg of lidocaine, both with an onset of action at 10 minutes and a duration of 50 minutes. During these two blocks, elevation of the ipsilateral lower palpebra was observed. All turtles maintained normal attitude and physiologic parameters throughout the trials.

Lidocaine at 5, 10, or 20 mg/kg did not reliably produce a brachial plexus blockade in adult eastern box turtles. Adverse effects were not identified in any turtles. Further studies are needed to determine the effective dose of analgesia and to confirm the accuracy of a blind perineural brachial plexus blockade technique in eastern box turtles. It is recommended that general anesthesia and supplemental methods of analgesia be used for forelimb procedures.

Acknowledgements

The authors wish to thank the North Carolina State University Veterinary Scholars Program and the Office of the Associate Dean for Research and Graduate Studies at the North Carolina State University College of Veterinary Medicine for supporting the participation of SMS and MAG.

Literature Cited

1.  Balko JA, Chinnadurai SK. 2017. Advancements in evidence-based anesthesia of exotic animals. Vet Clin North Am Exot Anim Pract 20:917–928.

2.  Mans C, Steagall P, Sladky KK. 2019. Regional anesthesia and analgesia. In: Divers SJ, Stahl SJ, editors. Mader’s Reptile and Amphibian Medicine and Surgery (3^rd edn). St. Louis (MO): Elsevier. p 475–479.

3.  Clabaugh K, Haag KM, Hanley CS, Latimer KS, Hernandez-Divers SJ. 2005. Undifferentiated sarcoma resolved by forelimb amputation and prosthesis in a radiated tortoise (Geochelone radiata). J Zoo Wildl Med 36:117–120.

4.  Latney LV, Beguesse K, Newton AL, Raphael BL. 2017. Management of a soft tissue sarcoma in a bog turtle (Glyptemys muhlenbergii). J Herpetol Med Surg 27:12–17.

5.  Mones AB, Gorges MA, Santangelo SM, Lewbart GA, Harrison TM, Gerard MP. 2021. Feasibility of a blind perineural injection technique for brachial plexus blockade in eastern box turtles (Terrapene carolina carolina): a cadaver study. Vet Anaesth Analg 48:789–797.