RESUMEN
Cataract surgery is predominantly performed under local/regional anesthesia, with or without sedation. The practice pattern of sedation is unknown and seems to vary significantly among institutions and countries, routinely administered in some parts of the world to the other extreme of none at all. The selection of sedative agents and techniques varies widely. Currently, there is no ideal sedative agent. Dexmedetomidine has gained recent attention for sedation in ophthalmic local/regional anesthesia due to its alleged advantages of effective sedation with minimal respiratory depression, decreased intraocular pressure, and reduced pain during the local anesthetic injection; however, they are subject to differing interpretations. Published literature also suggests that although dexmedetomidine sedation for cataract surgery under local/regional anesthesia is potentially useful, its role may be limited due to logistical difficulties in administering the recommended dose.
RESUMEN
Schizophrenia is ranked among the top 10 global burdens of disease. About 1% of people meet the diagnostic criteria for this disorder over their lifetime. Schizophrenic patients can develop cataract, particularly related to age and medications, requiring surgery and anesthesia. Many concerning factors, including cognitive function, anxiety, behavioral issues, poor cooperation and paroxysmal movements, may lead to general anesthesia as the default method. Antipsychotic agents should be continued during the perioperative period if possible. Topical/regional anesthesia is suitable in most schizophrenic patients undergoing cataract surgery. It reduces potential drug interactions and many postoperative complications; however, appropriate patient selection is paramount to its success. General anesthesia remains the primary technique for patients who are considered unsuitable for the topical/regional technique. Early involvement of a psychiatrist in the perioperative period, especially for patients requiring general anesthesia, is beneficial but often under-utilized. This narrative review summarizes the anesthetic considerations for cataract surgery in patients with schizophrenia.
RESUMEN
Sub-Tenon's block (STB) is a good technique of local anaesthesia for many types of eye surgery. It has a relatively good risk profile, in that sight- and life-threatening complications appear to be extremely rare. STB has gained popularity in the last three decades, with refinements including different types of blunt metal cannula, plastic cannulae and 'incisionless' approaches. Usage of STB varies significantly across the globe. This narrative review documents the historical evolution of STB techniques, anatomical and physiological considerations, its utility and suitability, complications, explores the current practice and possible future applications.