Does eliminating the preoperative history and physical make a difference in low-risk cataract surgery patients? A before and after study of 30-day morbidity and mortality

Objective: To evaluate the safety of omitting the conventional preoperative history and physical examination (H&P) for low-risk cataract surgery patients. Design: Comparison of outcomes before and after the January 1, 2015 system wide implementation of a program that eliminated the conventional preoperative H&P for low-risk patients as identified by a 12-item risk stratification questionnaire. Participants: Two separate groups of Winnipeg residents who had cataract surgery at the city's sole ophthalmological referral centre between July 1 and December 31, 2014 (preimplementation reference group) or between October 1, 2015 and March 31, 2016 (postimplementation intervention group). Methods: A detailed chart review was completed for cataract surgery patients who experienced a postoperative medical event (a composite of death or hospital admission or emergency department visit, identified within administrative databases) within 30 days of surgery. Nonfatal events were captured for all 7 hospitals and urgent care centres in the city, including the ophthalmological referral centre. Results: Postoperative medical events occurred in 114 of 2981 (3.82%) intervention group surgeries and 125 of 3037 (4.12%) reference group surgeries (Relative risk 0.92, 95% confidence interval 0.72 to 1.19, p = 0.6 Fisher exact test). Subgroup analyses of major medical events and medical events by affected organ system yielded no significant differences between the 2 groups. In the opinion of the physician chart reviewers, none of the events among low-risk patients in the intervention group were related to the omission of a conventional preoperative H&P. Conclusions: The risk of adverse medical events within 30 days of cataract surgery was not higher after the omission of the conventional preoperative H&P in patients screened to be low risk by a validated preoperative questionnaire.