Global survey on the utilisation and experiences with different retrobulbar anaesthesia techniques in horses.
Authors: Lieberth Simona, Thieme Katharina, Dancker Christian, Merle Roswitha, Eule Johanna Corinna
Journal: Equine veterinary journal
Summary
# Editorial Summary Retrobulbar anaesthesia (RBA) remains an essential technique for equine ocular surgery in standing sedated horses, yet practice patterns and complication profiles vary considerably across practitioners. This international cross-sectional survey of 238 equine veterinarians from 25 countries—predominantly specialists—examined injection techniques, medication choices, and adverse outcomes, revealing that the dorsal approach dominates (88.8% usage) alongside the 4-point block (34.8%), whilst ultrasound guidance remains underutilised at just 16.1%. Mepivacaine, lidocaine, and bupivacaine comprised the primary anaesthetic agents, with reported complications including inadequate anaesthesia (40.6%), exophthalmos (33.5%), chemosis (32.1%), and retrobulbar haemorrhage (22.8%)—notably, practitioners with higher equine caseloads experienced more injection-related complications but fewer postoperative complications, whereas those with greater ophthalmology specialisation reversed this pattern, showing fewer injection complications but more postoperative issues. The divergent complication profiles according to professional background suggest that technique refinement through specialisation reduces injection-related morbidity, though this may be offset by more complex surgical cases undertaken by ophthalmic specialists. For equine professionals, these findings underscore the value of dedicated training and experience in RBA technique selection, and indicate potential for improved outcomes through increased adoption of ultrasound-assisted needle positioning across all practitioner groups.
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Practical Takeaways
- •Dorsal and 4-point retrobulbar blocks are the preferred techniques globally; choice should be guided by your case experience level and specialty focus
- •Most complications from RBA are mild (lack of anaesthesia, chemosis, exophthalmos); severe complications are uncommon when proper technique is used
- •Developing ophthalmic experience significantly reduces injection-related complications, suggesting practitioners should seek training and mentorship to improve RBA technique proficiency
Key Findings
- •Dorsal approach was most commonly used (88.8%), followed by 4-point block (34.8%), with variation based on practitioner specialty
- •Lack of anaesthesia (40.6%), exophthalmos (33.5%), and chemosis (32.1%) were the most frequent complications, while severe complications were rare
- •Mepivacaine (67.4%), lidocaine (56.3%), and bupivacaine (37.9%) were the most commonly used local anaesthetic agents
- •As ophthalmic caseload increased, dorsal injection use increased and injection-related complications decreased, suggesting experience reduces injection-related problems