International variation in anesthesia care during cataract surgery - Results from the International Cataract Surgery Outcomes Study

Objectives: To describe international variation in anesthesia care and monitoring during cataract surgery and to discuss its implications for cost and safety. Methods: A standardized questionnaire was sent to random samples of ophthalmologists in the United States, Canada, and Barcelona, Spain, and to all ophthalmologists in Denmark. The survey was conducted in 1993 and 1994. Certified ophthalmologists who had performed 1 or more cataract extractions in the previous year were eligible for enrollment. Results: The response rates were 62% in the United States (n=148), 67% in Canada (n=276), 70% in Barcelona (n=89), and 80% in Denmark (n=82). The anesthetic technique for cataract surgery varied significantly between sites (P<.001). Surgeons reported that retrobulbar blocks were used for 46% of the cataract extractions in the United States, 70% in Canada, 66% in Denmark, and 31% in Barcelona. In Barcelona, general anesthesia was used for 23% of the cataract extractions; it was used for less than 3% of the extractions at the other 3 sites. Peribulbar blocks or topical anesthesia was used for the remaining extractions. In the United States, Canada, and Barcelona, surgeons reported that vital functions were monitored during more than 97% of the extractions and anesthesia surveillance was used during more than 78% of the extractions. In Denmark, ophthalmologists reported that vital functions were monitored and anesthesia surveillance was used for 1% of the cataract extractions (P<.001). Conclusions: Substantial international variation in anesthesia care and monitoring during cataract surgery was observed. The findings suggest a need far further research to determine whether less intensive monitoring is cost-effective.