A cadaver study comparing two approaches for performing maxillary nerve block in dogs.

Area of Science:

• Veterinary Anesthesiology
• Regional Anesthesia Techniques
• Maxillary Nerve Blocks

Background:

• Regional anesthesia is crucial for pain management in veterinary procedures.
• The maxillary nerve block is commonly used for dental and oral surgeries.
• Evaluating new techniques for improved success rates, especially by less experienced practitioners, is essential.

Purpose of the Study:

• To compare the efficacy of a modified infraorbital approach versus a traditional percutaneous approach for maxillary nerve blocks.
• To assess the success rate of these techniques when performed by inexperienced anesthetists.
• To evaluate potential complications associated with each approach.

Main Methods:

• A prospective, randomized, blinded controlled study was conducted using 37 euthanized dog heads.
• Four inexperienced anesthetists performed both the infraorbital (catheter-based) and percutaneous (needle-based) approaches.
• Methylene blue dye was injected, followed by dissection to evaluate nerve staining (maxillary and pterygopalatine nerves).

Main Results:

• The infraorbital approach achieved significantly higher staining of the maxillary nerve (>6 mm) in 64.9% of attempts compared to 21.6% for the percutaneous approach (p=0.001).
• Pterygopalatine nerve staining was also significantly higher with the infraorbital approach (70%) versus the percutaneous approach (21%) (p=0.001).
• No intravascular or intraneural injections were observed macroscopically with either technique.

Conclusions:

• The modified infraorbital approach demonstrated superior success rates for blocking the maxillary and pterygopalatine nerves compared to the percutaneous approach.
• This technique is more effective when performed by inexperienced anesthetists.
• The infraorbital approach appears to be a safe alternative, with no observed macroscopic complications.