Intrathecal mepivacaine after general anesthesia is an effective method of equine euthanasia when compared to intravenous pentobarbital.

This research analyzed intrathecal mepivacaine’s effectiveness in equine euthanasia and compared it to the traditional euthanasia method of intravenous pentobarbital.

Methodology

• The study utilized client-owned horses and those needing euthanasia due to concurrent research projects.
• The horses were randomly assigned to one of two groups: the first group were euthanized using intrathecal mepivacaine after anesthesia, and the second group through intravenous pentobarbital after sedation.
• All the horses used showed normal vital parameters and demonstrated no signs of infectious disease at euthanasia time.
• The intrathecal mepivacaine group received anesthesia before the mepivacaine dose. The second group was concurrently sedated, anesthetized, and euthanized using intravenous pentobarbital.
• Both groups were sedated using detomidine. The time from sedation to cessation of vital parameters like respiration, pulse, corneal reflex, and ECG was recorded.
• A blinded anesthesiologist recorded all euthanasias and later assessed the quality of sedation, anesthesia induction, and lateral recumbency using an independent scale.

Results

• The timeframe from detomidine administration to cessation of vital parameters was significantly longer in the intrathecal mepivacaine group compared to the one euthanized with pentobarbital.
• On a qualitative level, the scores for sedation or induction had no significant difference between the two groups. However, in terms of lateral recumbency, the anesthetized intrathecal mepivacaine group exhibited superior subjective performance.

Conclusions

• This study found that intrathecal mepivacaine presented a safe and effective alternative for euthanasia compared to intravenous pentobarbital. This offers a solution to concerns around barbiturate availability.
• The research also supplies practitioners with knowledge about what to anticipate when using the intrathecal mepivacaine method for euthanasia, i.e., a longer duration for the cessation of vital parameters.