Pre- and postoperative residualurine in 796 men aged > 65 years undergoing elective orthopaedic surgery in Denmark:A single-center, prospective cohort study

Background: <br/>Post-void residual urine (PVR) can be a preexisting or an unknown chronic disorder, but it can also occur after surgery. A pilot-study initiated in Elective Surgery Center, Silkeborg Regional Hospital led to a collaboration with a urologist to develop a flowchart to handle men with residual urine after elective surgery. Depending on the severity, men with significant PVR volumes were either recommend follow up by the general practitioner or referred to a urology outpatient clinic for further diagnose and/or treatment. <br/><br/>Aim: <br/>To determine the prevalence of pre- and postoperative PVR in men &gt;65 years undergoing common elective orthopedic surgeries (hip, knee or shoulder arthroplasty or spine surgery) and associated risk factors. <br/><br/>Materials and methods: <br/>A single-center, prospective cohort study. Male patients were consecutively included during one year from April 25 2022. Data was extracted from the electronic patient files: age, lower urinary tract symptoms (LUTS), co-morbidity (e.g. diabetes or neurological disease), type of surgery and anesthesia, opioid use, pre- and postoperative PVR. <br/><br/>Results: <br/>796 men were included; 316 knee-, 276 hip-, 26 shoulder arthroplasties and 178 lower back spinal surgeries. <br/><br/>95% (n=755) were bladder scanned preoperatively. 12% (n=89) had PVR 150-300ml, and 3% (n=23) had PVR &gt;300ml. <br/><br/>There was a higher risk of preoperative PVR ≥150ml in patients reporting LUTS, OR 1.97(1.28;3.03), having known neurological disease, OR 3.09(1.41;6.74), and the risk increased with higher age, OR 1.08 per year (1.04;1.12). Diabetes and the type of surgery was not associated with higher risk of PVR. <br/><br/>72% (n=569) had a postoperative bladder scan. <br/><br/>15% (95%CI: 12-19%) (n=70) patients without PVR preoperatively had PVR ≥150ml postoperatively. <br/><br/>Conclusion: <br/>Approximately 15% of the men had PVR ≥150ml preoperatively. <br/><br/>Neurological disease was the most severe risk factor and secondary if reporting LUTS. As expected, the risk increased with age. Interestingly, neither diabetes nor the type of surgery was associated with a higher risk. <br/><br/>15% of the men without preoperative PVR had PVR after surgery. It is not possible to conclude if it is transient or chronic but further studies are ongoing.