Subjective pain scale and the need for analgesia during shock wave lithotripsy

To investigate patients' opinions on the degree of pain during shock wave lithotripsy, and the need for analgesics in patients with urinary stone.

A prospective questionnaire study involving subjective pain assessment during and just after shock wave lithotripsy was performed in consecutive patients with uncomplicated renal or ureteral stones. The patients were given unbiased information on the analgesics prior to the procedure. Ten minutes after beginning shock wave lithotripsy, the degree of pain was rated by the patient using a 10-point visual analog scale. After the procedure, the patients were asked to complete a self-administered questionnaire. Based on the response for the questionnaire, the patients were divided as 'tolerable' or 'non-tolerable' group.

The results from 180 patients (males 113, females 67) with a mean age of 50.0 +/- 13.0 were analyzed. The average subjective pain score was 6.6 +/- 2.3 during the procedure, and 70 (38.9%) patients responded that they were able to tolerate the pain without analgesics. A total of 116 (64.4%) patients did not agree that analgesic should be recommended to other patients. Subjective pain score during the procedures was not affected by laterality, size of stone, level of education or socioeconomic status, but was affected by patient age (p = 0.042), sex (p = 0.012) and location of stone (p = 0.014). Right and kidney stones were significantly higher in the 'non-tolerable' group than in the 'tolerable' group (p = 0.003 and p = 0.011, respectively), and the 'non-tolerable' patient group had a significant higher pain score than the 'tolerable' group (p < 0.001).

Our result shows that subjective pain severity during shock wave lithotripsy is high but may be well tolerated in some patients. Our findings raise the question as to whether routine analgesics are required during newer generation shock wave lithotripsy procedures in all patients with a urinary stone.