A Comparative Study of Intravenous Versus Peribulbar Administration of Dexmedetomidine for Strabismus Surgery in Adults

Strabismus (misalignment of the eye) results from a difference in extraocular muscle function. Consequently, two different images, one from each eye, are transmitted to the brain, resulting in a loss of visual depth. In adults, cosmetic appearance is the main issue but sudden occurrence of strabismus may cause diplopia because the brain cannot suppress the overlapping images. The goal of strabismus surgery is to align the eyes, reduce diplopia, and restore binocular vision Ophthalmic regional block can be used as the primary anesthetic technique for strabismus surgery. The advantages of ophthalmic regional blockade include a reduced incidence of oculocardiac reflex (OCR) and emergence agitation, postoperative analgesia, and decreased postoperative nausea and vomiting (PONV).

Using various adjuvants has become a trend in regional anesthesia practice to improve the quality of anesthesia and prolong postoperative analgesia. Dexmedetomidine, an alpha-2 agonist has been proposed as a safe and effective adjunct capable of extending the duration of the single-shot block.

Perineural dexmedetomidine, when added to bupivacaine, has been shown to potentiate its effects, providing a better quality of anesthesia and postoperative analgesia. Intravenous (I.V.) dexmedetomidine, when used during regional anesthesia, has been shown to prolong sensory and motor blockade in addition to sedation and postoperative analgesia.

No previous studies where different routes of dexmedetomidine have been compared in adult strabismus surgery.