Hemiacidrin irrigations to dissolve stone remnants after nephrolithotomy. Problems with solution flow

Following surgery for branched renal calculi, hemiacidrin irrigation may be useful to dissolve any residual stones. Struvite, the mineral in these stones, is itself an alkaline buffer and can raise the pH of the irrigating solution rendering it ineffective. Large volumes of hemiacidrin must reach the stone remnants or they are unlikely to dissolve. Two cases are described in which creative positioning of the patient or the irrigation catheters was necessary to permit adequate amounts of hemiacidrin to reach and dissolve stone remnants.