Diagnostic yield and costs associated with a routine pre-operative COVID-19 testing algorithm for asymptomatic patients prior to elective surgery

Objectives: Infection with COVID-19 presents known and unknown perioperative risks to the patient and operative staff. Pre-operative testing protocols have become widespread, yet little is known about the utility of this practice in asymptomatic patients undergoing elective surgery. We describe the impact and cost of a routine testing protocol on elective surgical procedures in a retrospective series at a single institution. Methods: Standardized pre-operative COVID-19 testing in all surgical patients was implemented in May 2020. Health system protocol required testing 3 to 5 days before all elective surgery. Data stratified by surgical specialty were collected over the initial 90-day period and disposition over a period of 6-months was assessed for all positive and indeterminate results. Results: Thirty-one (0.41%) positive results amongst 7579 pre-procedural tests, including 3 of 792 (0.38%) for urologic procedures, were noted in asymptomatic patients. Following a positive test, 20 procedures (62.5%) were delayed an average of 49 days, 8 were not performed and 3 proceeded without delay. All 3 urologic procedures were delayed a mean of 59 days. Institutional cost per test ranged from $34-$54. The number needed to test for one positive result was 244 with a cost of $11,573 for each positive result. Conclusions: Institution of a universal preoperative COVID-19 screening protocol for asymptomatic, unvaccinated patients undergoing elective surgery identified clinically silent infection in 0.4% of cases with a significant associated cost. Risk and symptom-based testing is likely a better strategy for triaging resources.