Ultrasound-guided versus blind intercostal nerve injection in equine cadavers

Area of Science:

• Veterinary anatomy
• Equine regional anesthesia

Background:

• Accurate intercostal nerve blocks are vital for equine pain management.
• Variations in equine thoracoabdominal anatomy can challenge injection techniques.

Purpose of the Study:

• To detail equine thoracoabdominal anatomy.
• To compare ultrasound-guided versus blind thoracic intercostal nerve injections (T12-T18) in equine cadavers.

Main Methods:

• Eight equine cadavers underwent dissection and nerve injections.
• Injections used 3 mL of 0.05% methylene blue.
• Ultrasound-guided and blind techniques were compared on contralateral sides.

Main Results:

• Ultrasound guidance achieved higher nerve staining (83.7%) than blind injections (51.0%).
• Pleural puncture and intramuscular injections were less frequent with ultrasound guidance.
• The T18 (costoabdominalis) nerve showed significant anatomical deviation, impacting blind injection success.

Conclusions:

• Ultrasound guidance enhances the accuracy of equine intercostal nerve blocks.
• Detailed anatomical knowledge of the thoracoabdominal region, particularly T18, is essential for effective regional anesthesia in horses.