Ultrasound-guided quadratus lumborum block in sheep: A cadaveric study

Area of Science:

• Veterinary Anatomy
• Regional Anesthesia
• Surgical Techniques

Background:

• Ultrasound-guided regional anesthesia is increasingly utilized in veterinary medicine.
• Accurate targeting of specific fascial planes is crucial for effective nerve blockade.
• The quadratus lumborum (QL) plane offers potential for abdominal analgesia.

Purpose of the Study:

• To establish and evaluate an ultrasound-guided technique for the quadratus lumborum (QL) plane in sheep cadavers.
• To compare the spread of injectate between two distinct QL plane approaches.
• To identify the anatomical structures targeted by the developed technique.

Main Methods:

• Prospective anatomical study using 13 sheep cadavers.
• Phase 1: Dissection and 3D CT reconstruction for anatomical evaluation.
• Phase 2: Comparison of lateral (LQL) and transmuscular (TQL) ultrasound techniques.
• Phase 3: Dye injections via LQL technique and subsequent dissection to assess spread.

Main Results:

• The lateral QL (LQL) technique demonstrated no undesired dye spread.
• The transmuscular QL (TQL) technique resulted in retroperitoneal space spread in one instance.
• LQL injections successfully stained the 13th thoracic, first, second, and third lumbar nerves, and sympathetic trunk segments.

Conclusions:

• The ultrasound-guided lateral quadratus lumborum (LQL) approach is a feasible technique in sheep cadavers.
• This method allows for targeted staining of spinal nerves crucial for cranial abdominal innervation.
• Further investigation in live animals is recommended to validate clinical applicability.