Analgesia in piezoelectric SWL: comparative study of kidney and upper ureter treatments

The development of newer-generation lithotripters has reduced the pain associated with SWL, but many patients still require some form of sedation. We prospectively compared the analgesic requirements for kidney and upper ureteral treatments. Predictive factors for pain during piezoelectric SWL were also studied.

A total of 102 consecutive patients without any previous experience of SWL were treated for renal (N = 70) or upper ureteral (N = 32) calculi using the EDAP LT02 lithotripter. The stones' largest diameter ranged from 4 to 30 mm (mean 9 mm). Patients were given an oral dose of 60 mg of dextropropoxyphene hydrochloride and 800 mg of paracetamol associated with 100 mg of ketoprofene per rectum 30 minutes before treatment. The SWL session was begun at low intensity and increased to the maximal range of energy as rapidly as could be tolerated by the patient. The amount of pain during treatment was recorded according to a visual analogue scale (VAS). Further analgesia using intravenous alfentanil was given as required by the severity of the pain. Visual analog pain scores, additional sedation requirements, and success rates after one session were analyzed.

The VAS scores and intravenous sedation requirements were significantly lower for patients with upper ureteral stones than for those with renal calculi (P < 0.01). The stone-free rates after one session were, respectively, 90% and 73% (P < 0.05). On the other hand, SWL tolerance was significantly lower for women presenting with renal stones (P < 0.05).

Piezoelectric SWL without intravenous sedation is suitable for the treatment of upper ureteral calculi. However, such an approach is less efficient in the management of kidney stones, especially for female patients.