Prospective evaluation of complications using the modified Clavien grading system, and of success rates of percutaneous nephrolithotomy using Guy′s Stone Score: A single-center experience

Abstract

Introduction and Objectives:To prospectively document the perioperative complications of percutaneous nephrolithotomy (PCNL) using the modified Clavien grading system. Evaluation of complications and clearance rates according to stone complexity using the validated Guy's Stone Score (GSS) was also done.Materials and Methods:A total of 221 renal units underwent 278 PCNL procedures at a urology resident training center between September 2010 and September 2011 and data were recorded prospectively in our registry. Patients with co-morbidities like diabetes, renal failure, hypertension and cardiopulmonary diseases were excluded. Stone complexity was classified according to the GSS while peri-operative complications were recorded using the modified Clavien grading system.Results:Two hundred and forty-five complications were encountered in 278 PCNL procedures involving 116 renal units (41.72%). Complications of Grades 1, 2, 3a, 3b, 4a, 4b and 5 were seen in 52 (18.7%), 122 (43.8%), 42 (15.1%), 18 (6.4%), 6 (2.1%), 4 (1.4%) and 1 (0.3%) renal units respectively. There were 68, 98, 50 and 5 renal units in GSS I, II, III and IV groups, respectively. All grades of complications were more common in GSS III and IV (P<0.05). For GSS I, II, III and IV 100%, 74%, 56% and 0% of renal units, respectively, were stone-free after one session and 0%, 24%, 44% and 60% respectively needed two sessions to be stone-free.Conclusion:Although the complication rates were higher most were of low grade and self-limiting. Complications were significantly more common with higher GSS and the GSS effectively predicted stone-free rates.

Value of preoperative stone scoring systems in predicting the results of percutaneous nephrolithotomy

“…In two different studies conducting external validation of the Guy scoring system, Mandal and Ingirmasson evaluated this scoring system as an efficient instrument in predicting the stone-free status [ 12 , 13 ].…”

“…In their series involving 278 PCNL cases, Mandal et al observed that the stone-free rates decreased as 100%, 74%, 56%, and 0% according to the GS 1, 2, 3, 4 scores respectively [ 12 ].…”

Grading of complications of transurethral resection of bladder tumor using Clavien–Dindo classification system

“…This classification system has been used for grading complications in oncological procedures such as radical cystourethrectomy[ 12 ] and radical prostatectomy;[ 13 ] laparoscopic procedures such as pyeloplasty[ 14 ] and live donor nephrectomy;[ 15 ] endourological procedures such as transurethral resection of prostate,[ 16 ] percutaneous nephrolithotomy,[ 17 ] and semi-rigid ureteroscopy. [ 18 ] However, the modified CCS has been less frequently used for TURBT.…”

Guy’s Stone Score (GSS) Based on Intravenous Pyelogram (IVP) Findings Predicting Upper Pole Access Percutaneous Nephrolithotomy (PCNL) Outcomes

“…At the current time, the Guy's Stone Scoring (GSS) system [3–7], the STONE nephrolithometry scoring system [8, 9], and the CROES (Clinical Research Office of Endourological Society) nomogram [10] are used for the prediction of the success rate and possible complications following PCNL in research and clinical practice. Previous studies reported that the Guy's stone score is significantly associated with stone-free status [3–7]; however other studies reported an association of this score with complications [4, 6]. STONE nephrometric scores were significantly associated with stone free status but not with postoperative complications [8, 9].…”