Contribution of Hypersensitivity to Postureteroscopy Ureteral Stent Pain: Findings From Study to Enhance Understanding of Stent-associated Symptoms

OBJECTIVE To examine the relationships between preoperative hypersensitivity to pain and central sensitization, and postoperative ureteral stent pain after ureteroscopy (URS) for urinary stones. METHODS Adults enrolled in the STudy to Enhance uNderstanding of sTent-associated Symptoms (STENTS) underwent quantitative sensory testing (QST) prior to URS and stent placement. Hypersensitivity to mechanical pain was assessed using a pressure algometer. Participants rated their pain intensity to pressure applied to the ipsilateral flank area and lower abdominal quadrant on the side of planned stent placement, and the contralateral forearm (control). Pressure pain thresholds were also assessed. Central sensitization was assessed by applying a pointed stimulator (pinprick) and calculating the temporal summation. Postoperative stent pain intensity and interference were assessed using PROMIS questionnaires. Data were analyzed using repeated -measures mixed -effects linear models. RESULTS Among the 412 participants, the median age was 54.0 years, and 46% were female. Higher preoperative pain ratings to 2 kg and 4 kg mechanical pressure to the ipsilateral flank and abdominal areas were associated with higher postoperative stent pain intensity with the stent in situ. Greater degree of central sensitization preoperatively, manifesting as higher temporal summation, was associated with higher postoperative pain intensity. Factors associated with preoperative hypersensitivity on QST included female sex, presence of chronic pain conditions, widespread pain, and depression. CONCLUSION Hypersensitivity to pain and central sensitization preoperatively was associated with postoperative ureteral stent pain, suggesting a physiologic basis for stent symptom variation. QST may identify patients more likely to develop stent pain after URS and could inform selection for preventive and interventional strategies. UROLOGY 184: 32-39, 2024. (c) 2023 Elsevier Inc. All rights reserved.