Reduction of pre-procedural anxiety for repeat sessions in extracorporeal shockwave lithotripsy (ESWL) reduces pain intensity: A prospective observational study

Pain control is a major determinant for successful stone clearance in extracorporeal shockwave lithotripsy (ESWL) for urolithiasis. Pain perception during ESWL may be influenced by patient factors like gender, age, body habitus and anxiety level, and stone related factors like size, laterality and location of stone. We investigated in general, the confounding patient and stone factors influencing pain perception during ESWL with importance given to procedural anxiety in first and the subsequent session of ESWL. This was a prospective observational study of all new consecutive patients who underwent ESWL for a period of 1 year at a tertiary Urological Centre. Demographic and stone anthropometry were analyzed. Pre-procedural anxiety was assessed prior to procedure using hospital anxiety and depression score (HADS) and pain was scored using numerical rating scale-11 at baseline, 30-minutes (i.e., during) and 24 hours after ESWL. Univariate and multivariate analysis for confounding factors included HADs were performed for pain perception. A P value < .05 was considered to be statistically significant. For the study duration, 119 patients were recruited and 72 of them returned for a second session. Procedural anxiety was the only independent factor affecting pain score in ESWL for the first session in multivariate analysis. A statistically significant reduction of mean procedural anxiety score from 6.7 ± 4.5 to 3.2 ± 2.7 (P < .05) for the second ESWL session was observed (n = 72). This was in conjunction with statistical reduction of mean pain score 30 minutes after ESWL from 5.2 ± 2.1 to 4.2 ± 2.1 (P < .05). Patients with HADS ≥ 8 had statistically significant higher mean pain score at all 3 intervals in the first ESWL session. This study has shown that pre-procedural anxiety mainly anticipatory, reduces and shows reduction in pain intensity among patients undergoing repeat ESWL. Hence, anxiety reducing methods should be explored in patients undergoing ESWL to avoid unnecessary analgesic use.