Bloqueio do plano eretor espinhal associado à anestesia epidural em canino submetido à estabilização da segunda vértebra lombar – relato de caso

Abstract

The Erector Spinae Plane Block (ESP block) is an anesthetic method that falls under the category of locoregional anesthesia, with great potential for use in various surgical interventions and pain management, whether chronic or acute. It is one of the most recent fascial plane block techniques in human medicine, with a relatively recent description in veterinary medicine, but it has shown great effectiveness in providing analgesia. Its technique is easy to apply, rapid, has a good safety margin, and also ensures the patient a significant reduction in the need for high doses of anesthetics and analgesic drugs. The block requires the aid of ultrasound for its execution, being performed by administering the local anesthetic into the interfascial plane between the erector spinae muscle complex and the transverse processes of the vertebrae. On the other hand, epidural blockade is a well-known technique for being easy to perform, with minimal influence on cardiorespiratory alterations, and is widely used in procedures such as those involving the pelvic limbs, the caudal abdomen, among others. This report aims to describe the use of the ultrasound-guided erector spinae plane block, its analgesic potential during the surgery of a dog undergoing stabilization of the second lumbar vertebra (L2), its benefits, and effects on postoperative recovery when combined with epidural blockade. The animal described in this case is a 2-year-old male dog, weighing 13.8 kg, with no defined breed, suffering from a luxation between the 1st (L1) and 2nd (L2) lumbar vertebrae. The dog was premedicated with dexmedetomidine at a dose of 3 µg/kg, combined with morphine at 0.2 mg/kg, both administered intramuscularly (IM). Anesthetic induction was performed with propofol at 3 mg/kg, intravenously (IV). Anesthetic maintenance was carried out with isoflurane diluted in pure oxygen, combined with continuous IV infusion of ketamine at a rate of 0.6 mg/kg/h. The dog was positioned in sternal abdominal recumbency with the pelvic limbs flexed, and with the aid of a linear transducer, the transverse processes of L1 and L2 were identified, allowing visualization and administration of the local anesthetic into the interfascial plane between the erector spinae muscle complex and the transverse processes. The local anesthetic used was bupivacaine 0.5% without vasoconstrictor, at a dose of 2 mg/kg, divided into two points and diluted in NaCl to a final volume of 5 mL for each application site. The physiological parameters, such as heart rate, respiratory rate, temperature, oxygen saturation, and systolic pressure, remained within normal expected levels, except for temperature, which decreased to 35°C but was promptly restored. The anesthetic recovery was smooth and rapid at the end of the surgical procedure, with no significant signs of pain in the immediate postoperative period and during the pain tests conducted. It was concluded that the anesthetic protocol used proved to be an excellent option for ensuring transoperative analgesia and adequate postoperative recovery for the stabilization of the L2 luxation.