Preoperative Cardiac Stress Tests Ordered in the Preoperative Evaluation Clinic: A Retrospective Review of Ordering Patterns

BACKGROUND: The role of anesthesiologists has expanded from operating rooms to preoperative evaluation clinics. This role involves performing preoperative cardiovascular evaluation and optimization of patients before elective surgery, which can include ordering cardiac stress tests. We aimed to study the ordering patterns by anesthesiologists for preoperative cardiac stress tests, focusing on whether societal and institutional guidelines and recommendations were used. Choice of type of cardiac stress test was also examined. METHODS: A single center retrospective chart review from December 1, 2005 to May 31, 2015 was performed on 492 patients who had a cardiac stress test ordered by an anesthesiologist. Patients were categorized by indication for ordering the cardiac stress test based on societal practice guidelines, institutional guidelines or other relevant reasons at the time of patient encounter. Those “other” category cardiac stress tests were assessed for indication and evaluated by physician peer review to see if there was peer agreement for being appropriately ordered. Exercise electrocardiography (ECG) cardiac stress tests ordered were evaluated for appropriateness based on baseline resting ECG findings. Patients with left bundle branch block (LBBB) or right ventricular (RV) pacing were evaluated for appropriateness of proper cardiac stress test modality based on whether a pharmacological vasodilator cardiac stress test was ordered. RESULTS: Analysis of the cardiac stress tests ordered showed that 43% were ordered according to American College of Cardiology/American Heart Association guidelines, 29% were ordered according to institutional guidelines, and 28% were categorized as “other”. Of the 28% “other” cardiac stress tests, 53% were in agreement for ordering by peer review. Sixty-four exercise ECG cardiac stress tests were ordered, of which 58% were appropriate based on having no baseline resting ECG abnormalities. Fifty-one patients were identified as having a resting ECG of LBBB or RV pacing of which 41% had an appropriate pharmacological vasodilator cardiac stress tests ordered. CONCLUSIONS: Anesthesiologists order most preoperative cardiac stress tests according to professional societal or institutional guidelines (72%), yet they are not always choosing the best modality of cardiac stress test. A significant portion of cardiac stress tests are ordered (28%) based on clinical judgment, likely due to the lack of guidelines and recommendations being all-encompassing on many commonly encountered preoperative patient situations.