Caudal intercostal block for abdominal surgery in horses.

The research article explores the potential of a caudal intercostal block for abdominal surgery (CIBAS) in providing local anesthesia to horses undergoing celiotomy, thus helping in pain management without causing sedation or ataxia, while promoting muscle relaxation for easier surgical closure.

Objective of the Research

• The primary aim of this study is to ascertain the efficacy of a caudal intercostal block for abdominal surgeries (CIBAS) in horses. The primary interest in this method stems from the limitations of current systemic analgesic options which often induce sedation and ataxia, impacting recovery from surgery.

The Proposed Technique – Caudal Intercostal Block for Abdominal Surgery (CIBAS)

• The intercostal nerves from the 10th to the 17th ribs and the costoabdominal nerve to the 18th rib are the primary points of interest. These nerves influence the areas of the abdominal wall impacted by a ventral midline celiotomy incision.
• The ventral cutaneous branches of these nerves serve the skin of the ventral abdomen, while lateral cutaneous branches may further affect the ventral body wall’s layers.

Method Implementation

• For the CIBAS, the haired skin over ribs T10-T18 is clipped and prepared aseptically. A one-inch, 22 G needle is inserted at each intercostal space up to the caudal rib edge where the intercostal nerve passes.
• Aspiration of the syringe is done before application to confirm needle position, followed by the injection of 5 to 10 ml of 0.5 per cent bupivacaine (0.3 ml kg-1 total), mixed with dexmedetomidine (1 μg kg -1 total), per site.
• Dexmedetomidine is used as an additive because it has been found to extend sensory blockage.

Flexibility of CIBAS and Contraindications

• CIBAS has minimal contraindications, much like other perineural locoregional techniques. It can be performed during preoperative sterile surgical preparation with the horse in dorsal recumbency due to the often emergent nature of equine abdominal surgery.
• For elective procedures, the CIBAS can be carried out under standing sedation before the induction of general anesthesia.

Use of Imaging

• Ultrasound guidance is utilized to increase the accuracy and safety of this technique.