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One of the consultant's roles is to make recommendations regarding the use of medications in the perioperative period. Unfortunately, the data in this area are often insufficient to provide evidence-based recommendations. In this article, we have provided advice considering the pharmacokinetics of the drug, the effect on the primary disease of stopping medications, and the effect of the medication on perioperative risk, including potential drug interactions with anesthetic agents.

Background: Routine preoperative medical testing is commonly performed in patients scheduled to undergo cataract surgery, although the value of such testing is uncertain. We performed a study to determine whether routine testing helps reduce the incidence of intraoperative and postoperative medical complications., 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 battery of medical tests (electrocardiography, complete blood count, and measurement of serum levels of electrolytes, urea nitrogen, creatinine, and glucose), in addition to a history taking and physical examination. Adverse medical 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 patients who underwent 9624 operations that were preceded by routine testing. The most frequent medical events in both groups were treatment for hypertension and arrhythmia (principally bradycardia). The overall rate of complications (intraoperative and postoperative events combined) was the same in the two groups (31.3 events per 1000 operations). There were also no significant differences between the no-testing group and the testing group in the rates of intraoperative events (19.2 and 19.7, respectively, per 1000 operations) and postoperative events (12.6 and 12.1 per 1000 operations). Analyses stratified according to age, sex, race, physical status (according to the American Society of Anesthesiologists classification), and medical history revealed no benefit of routine testing., Conclusions: Routine medical testing before cataract surgery does not measurably increase the safety of the surgery.

The statistical and practical implications of including second eye surgeries were examined in a clinical trial designed to evaluate the impact of routine preoperative testing prior to cataract surgery on major medical events occurring within seven days following surgery. In order to detect a 0.8% difference in the rates of rare major medical events between the tested and untested groups, 20,000 surgeries must be randomized. About 30% of cataract operations were estimated to be done on second eyes of patients already included in the cohort. Different options for dealing with second eye surgeries were: (1) exclusion of all second eye surgeries, (2) inclusion of second eye surgeries only if the first eye is not enrolled, (3) inclusion of first and second eyes but randomization of patients rather than eyes, and (4) inclusion of first and second eyes but randomization of surgeries rather than patients. The final decision was to exclude second eye surgeries done within 28 days of first eye surgeries, but to rerandomize all other second eye surgeries. Differences in event rates between treatment groups can be estimated using Generalized Estimating Equations, and the association between outcomes of first and second eye operations estimated with pairwise odds ratios. An anticipated small positive correlation is likely to have minimal impact on statistical power and effective sample size.

To assess variation in reported use of preoperative medical tests in patients undergoing cataract surgery and to identify factors that influence test use by different physician groups we performed a national survey of ophthalmologists, anesthesiologists, and internists. Participants included randomly selected members of American professional societies who provided care to one or more patients undergoing cataract surgery in 1991. Responses were obtained from 538 (82%) of 655 eligible ophthalmologists, 109 (76%) of 143 anesthesiologists, and 54 (44%) of 122 internists. Fifty percent of ophthalmologists, 40% of internists, and 33% of anesthesiologists frequently or always obtained a chest x-ray film, while 20% of ophthalmologists, 27% of internists, and 37% of anesthesiologists never obtained a chest x-ray film for patients being considered for cataract surgery who had no history of major medical problems (P < .01 for differences between ophthalmologists and the other groups). Similarly, 70% to 90% of ophthalmologists, 73% to 79% of internists, and 41% to 79% of anesthesiologists frequently or always obtained a complete blood cell count, electrolyte panel, and electrocardiogram, while 4% to 11% of ophthalmologists, 13% to 17% of internists, and 9% to 28% of anesthesiologists never obtained these tests for such patients. Many respondents (32% to 80%) believed tests were unnecessary but cited multiple reasons for obtaining tests (eg, medicolegal concerns and institutional requirements). Many physicians in each group viewed preoperative evaluations as screening opportunities or believed that one of the other two types of physicians "required" tests. We conclude that marked variation exists within and across physician specialties in the use and rationale for use of medical tests in patients undergoing cataract surgery.