The value of routine preoperative medical testing before cataract surgery

Background Routine preoperative medical testing is commonly performed in pa tients scheduled to undergo cataract surgery, although the value of such te sting is uncertain. We performed a study to determine whether routine testi ng helps reduce the incidence of intraoperative and postoperative medical c omplications. Methods We randomly assigned 19,557 elective cataract operations in 18,189 patients at nine centers to be preceded or not preceded by a standard batte ry of medical tests (electrocardiography, complete blood count, and measure ment of serum levels of electrolytes, urea nitrogen, creatinine, and glucos e), in addition to a history taking and physical examination. Adverse medic al events and interventions on the day of surgery and during the seven days after surgery were recorded. Results Medical outcomes were assessed in 9408 patients who underwent 9626 cataract operations that were not preceded by routine testing and in 9411 p atients who underwent 9624 operations that were preceded by routine testing . The most frequent medical events in both groups were treatment for hypert ension and arrhythmia (principally bradycardia). The overall rate of compli cations (intraoperative and postoperative events combined) was the same in the two groups (31.3 events per 1000 operations). There were also no signif icant differences between the no-testing group and the testing group in the rates of intraoperative events (19.2 and 19.7, respectively, per 1000 oper ations) and postoperative events (12.6 and 12.1 per 1000 operations). Analy ses stratified according to age, sex, race, physical status (according to t he American Society of Anesthesiologists classification), and medical histo ry revealed no benefit of routine testing. Conclusions Routine medical testing before cataract surgery does not measur ably increase the safety of the surgery. (N Engl J Med 2000;342:168-75.) (C ) 2000, Massachusetts Medical Society.