Percutaneous Nephrolithotomy in a Previously Operated Kidney

To ascertain the safety and efficacy of percutaneous nephrolithomy in patients with previous open renal surgery.

Descriptive study.

The Kidney Centre Postgraduate Training Institute, Karachi from January to December 2018.

Patients with previous open renal surgery underwent percutaneous nephrolithomy during study period (Group A). Equal number of percutaneous nephrolithomy patients without previous open surgery taken as controls (Group B). Safety was defined in terms of 'blood loss' as change in hemoglobin (HB) level and 'blood transfusion,' while efficacy was defined in terms of 'stone clearance' and were compared between both the groups.

There were a total of 87 patients. Both groups had comparative gender ratio [p = 0.858]. Mean age [p = 0.132] and BMI [p = 0.879] of patients in both groups was not significantly different from each other. Both groups showed no statistically significant difference in terms of values of stone size [p = 0.186], stone laterality [p = 0.437] stone location [p = 0.949], preoperative Hb [p = 0.095], postoperative Hb [p = 0.423] and change in Hb (indicating blood loss, p = 0.398). Puncture levels were significantly different among both groups (supracostal puncture in 18 and 36 patients; infracostal puncture in 63 and 51 patients in groups A and B, respectively, p = 0.006), while operative time [p = 0.787], calyx punctured [p = 0.051], double puncture [p = 0.787], nephrostomy tube [p = 0.288] were statistically not different among groups. Similar number of patients demonstrated residual stones [p = 0.773], along with residual stone sizes [Group A (0.5; 0.5) and Group B (0.65; 0.38)] [p = 0.445]. Intra- and postoperative complications like blood transfusion [p = 0.700] and fever [p = 1.000] along with hospital stay [p = 0.614] were comparable among groups.

Percutaneous nephrolithomy is safe and effective in previously operated kidneys despite the possibility of calyceal anatomy distortion and scarring. Key Words: Percutaneous nephrolithotomy, Open surgery, Kidney calculi.