Does more testing in routine preoperative evaluation benefit the orthopedic patient? Case control study from a resource-constrained setting

Background: Routine preoperative tests in healthy patients not only cause extra anxiety, but may delay treatment without influencing surgical plan. This has worse impact in resource-constrained settings where fee for service rather than health insurance is the usual norm. Investigators aim to determine if “routine” pre-operative tests are justified in healthy orthopedic patients. Methods: We conducted a non-commercialized, non-funded matched case control study in tertiary care university hospital and a level-1 trauma centre for healthy patients (ASA-1&2) admitted from January 2014–December 2016 for elective orthopedic intermediate and major procedures. Cases (patient who had a change in his/her surgical plan after admission) and controls were selected independently of the exposure of interest then matched randomly to cases on age, gender and procedure type. Primary exposure was the routine preoperative lab tests, as defined by the American Society of Anesthesiologist, which included 13 blood tests. Analysis was done using Principle Component Analysis and Conditional logistic regression at univariate and multivariable levels reporting matched adjusted Odds Ratios. The data was reported in line with STROCSS criteria. Results: Overall, 7610 preoperative tests were done for 670 patients with 62% men among cases and 53% men among controls with mean age of 49.9±22.5 years and 41.1±23.0 years, respectively. There were 1076 (14%) abnormal result that influenced surgical plan in 0.96% cases only. Matched adjusted OR with 95% confidence interval of primary exposure was insignificant. Conclusion: Routine preoperative tests were superfluous and did not influence the surgical plan when adjusted for other variables in the model as well as after matching on potential confounders. This study would be amongst first steps to move towards an evidence based surgical practice for preoperative evaluation.