The learning curve in minimally invasive percutaneous nephrolitholapaxy: a 1-year retrospective evaluation of a novice and an expert.
OBJECTIVE
The aim of this study was to compare a novice surgeon with an expert surgeon independently performing minimally invasive percutaneous neprolitholapaxy (PCNL) excluding the influence of the expert in the learning curve.


METHODS
Clinical records of 84 patients (novice: n = 35; expert: n = 49) undergoing minimally invasive PCNL between 04/2007 and 04/2008 were retrospectively reviewed for the following parameters: drop in hemoglobin, operative and fluoroscopy time, length of hospital stay, stone-free rate and complication rate. Complications were graded according to the Clavien classification. Statistical analysis was carried out by student's t test (Chi-square test) with p < 0.05 considered significant.


RESULTS
The novice surgeon experienced longer median operative and fluoroscopy time, lower stone-free rate and higher re-treatment rate (all p < 0.005) but no longer length of hospital stay (p = 0.19) compared to the experienced surgeon. The novice showed a notable improvement in operating time (p = 0.0208). Altogether, 16 complications occurred in 84 minimally invasive PCNL (19.1%) with five patients (6.0%) encountering grade III complications. Four patients (8.2%) treated by the expert surgeon developed complications (all grade I/II) compared to 12 of the patients (34.3%) treated by the novice surgeon (p = 0.0265). All grade III complications occurred in the first 20 patients of the novice surgeon group.


CONCLUSIONS
Despite longer operating time and a lower initial stone-free rate, the novice showed a significant improvement with growing experience and a low rate of higher grade (≥IIIa) complications. This demonstrates that the concept of minimally invasive PCNL can also be learned by urologists who do not have the support of an experienced colleague without endangering patient safety.
Schilling
David
D
Department of Urology, University Hospital Tuebingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany. david.schilling@med.uni-tuebingen.de
Gakis
Georgios
G
Walcher
Ute
U
Stenzl
Arnulf
A
Nagele
Udo
U
D000328:Adult; D000368:Aged; D002983:Clinical Competence; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D015994:Incidence; D007669:Kidney Calculi / Q000601:surgery*; D059032:Learning Curve; D007902:Length of Stay; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000193:education / Q000379:methods*; D009403:Nephrostomy, Percutaneous / Q000379:methods*; D011183:Postoperative Complications / Q000453:epidemiology; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome
Urology. 2010 Jan;75(1):51-5
19781744
J Endourol. 2005 Apr;19(3):279-82
15865512
Eur Urol. 2007 Jul;52(1):206-11
17229522
J Endourol. 2008 Sep;22(9):1851-3; discussion 1857
18811465
Eur Urol. 2007 Apr;51(4):899-906; discussion 906
17095141
Urology. 2006 Sep;68(3):489-93; discussion 493-4
16979734
Aktuelle Urol. 2009 Nov;40(6):351-4
19795340
Eur Urol. 2008 Jan;53(1):184-90
17651892
J Endourol. 2007 Apr;21(4):393-6
17451328
J Endourol. 2007 Sep;21(9):1113-6
17941796
Urology. 2001 Sep;58(3):345-50
11549477
Ann Surg. 2009 Aug;250(2):187-96
19638912
J Endourol. 2007 May;21(5):545-50
17523912