What medication is typically used for a subsacral nerve block?

• A. Bupivacaine
• B. Lidocaine/ethyl alcohol
• C. Procaine
• D. Ketamine

Answer: (B)

The use of lidocaine combined with ethyl alcohol for a subsacral nerve block is primarily due to the effectiveness of this combination in providing adequate analgesia in the pelvic region. Lidocaine is a local anesthetic that temporarily disrupts nerve transmission, and when combined with ethyl alcohol, the potency and duration of the nerve block can be enhanced. This makes the combination particularly useful for procedures requiring prolonged analgesia in the lower back or pelvic area, where the subsacral nerves are located.

In this context, the combination relies on the anesthetic properties of lidocaine and the sclerosing effect of ethyl alcohol, which can further inhibit nerve function. This approach is often preferred in veterinary medicine, especially in large animals, to facilitate certain surgical or diagnostic interventions while minimizing the stress and discomfort experienced by the animal.

Other medications listed, while they each have their own applications in anesthesia and pain management, do not possess the specific properties or the same level of efficacy for a subsacral nerve block as the lidocaine/ethyl alcohol combination.