Prospective randomized study of various techniques of percutaneous nephrolithotomy

To compare the modifications of the technique of percutaneous nephrolithotomy (PCN), including "mini-PCN" and tubeless PCN, to establish which technique is associated with the least morbidity and complications.

We performed a prospective randomized trial to assess the efficacy and morbidity of each method of percutaneous renal access. Standard PCN involved tract dilation to 30F for passage of a 34F working sheath, and our "mini-PCN" involved tract dilation to 22F for passage of a 26F sheath. Tubeless PCN involved the use of a double-J stent for internal drainage without the use of a nephrostomy tube for external drainage at termination of the procedure. Thirty patients (10 patients in each group) were enrolled, and 27 patients completed the study. All three groups were compared with regard to postoperative pain using a validated pain questionnaire comprised of a visual analogue scale and a verbal rating scale. The operative time, estimated blood loss, stone burden, procedure success rate, stone-free rate, length of hospitalization, total procedural cost, and complications were also compared for each technique.

The tubeless PCN population required less morphine use, had a decreased length of hospitalization, and had a smaller total procedural cost compared with the other two groups. One complication was noted in both the standard and mini-PCN groups, consisting of renal bleeding requiring a 2 and 3-U blood transfusion in the standard and mini-PCN groups, respectively.

The tubeless technique is associated with the least amount of morbidity and the greatest cost efficiency compared with the other techniques. No overall advantage was found for the mini-PCN versus the standard technique, but the mini-PCN is at a slight disadvantage because of poorer visualization and optics and difficulty with use of the nephroscopic graspers.