An audit of unnecessary preoperative urea and electrolyte panel tests in patients undergoing major orthopaedic surgery at a quaternary South African hospital

Abstract

Background: Preoperative urea and electrolyte (U&E) panels are frequently requested for major surgery patients at risk for postoperative acute kidney injury (AKI). There is only one published study that has audited unnecessary preoperative U&E test panel utilisation in major surgery patients at a South African (SA) public sector hospital. This has significant implications for laboratory workloads, healthcare expenditure, and patient-friendly practice in the resource-limited SA public healthcare sector. Objective: To audit preoperative U&E panel requests in a sample of SA patients undergoing major orthopaedic surgery. Methods: We conducted a retrospective audit of adult primary hip arthroplasty patients who attended a quaternary SA hospital. Data on demographics, medical history, preoperative anaesthetic evaluations, operation details, and U&E panel requests were collected from each patient’s medical chart. The National Institute for Health and Care Excellence (NICE) guidelines, based on American Society of Anesthesiologists (ASA) grading and the presence of AKI risk factors, was used to distinguish between necessary and unnecessary preoperative U&E requests. We used descriptive statistics to analyse our study data. Results: Of the 175 patients comprising our study sample, 23 (13.1%) had preoperative U&E panels requested unnecessarily. All 23 patients were otherwise healthy and did not have any AKI risk factors. Conclusion: A small proportion of preoperative U&E test panels in our study sample of major orthopaedic surgery patients were deemed unnecessary. With that being said, there is still room for improvement in practices around preoperative U&E panel requests, which could be achieved through educational, computerised, and audit feedback interventions.