Impact of the learning curve on perioperative outcomes in patients who underwent robotic partial nephrectomy for parenchymal renal tumours

Abstract

Background: Robot-assisted partial nephrectomy (RAPN) is an emerging, minimally invasive technique to treat patients with small renal masses.

Objective: To evaluate the impact of the learning curve on perioperative outcomes such as operative times and warm ischaemia times (WIT), blood loss, overall complications, and renal function impairment in patients who underwent RAPN.

Design, setting, and participants: We collected prospectively the clinical and pathologic records of 62 consecutive patients who underwent RAPN between September 2006 and November 2009 for renal tumours at a nonacademic teaching institution by a single surgeon with extensive prior robotic experience.

Interventions: The surgeon used transperitoneal RAPN with excision of an adequate rim of healthy peritumour renal parenchyma.

Measurements: Perioperative parameters, pathologic outcome, and short-term outcomes for renal function were recorded. The effects of the learning curve on the previous reported perioperative and functional outcomes was studied.

Results and limitations: The mean pathologic tumour size was 2.8 +/-1.3 cm. A pelvicaliceal repair was needed in 33 cases (53%). The mean console time was 91 +/-33 min (range: 52-180), with a mean WIT of 20 +/- 7 min (range: 9-40). Warm ischaemia (<20 min) and console times were optimised after the first 30 (p<0.001) and 20 cases (p<0.001), respectively. Pathologic results yielded a positive surgical margin (PSM) rate of 2%. Mean creatinine level changed from a baseline value of 1.02 +/- 0.38 mg/dl to 1.1 +/- 0.7 mg/dl 3 mo after surgery. Estimated glomerular filtration rate changed from a baseline value of 81.17 +/- 29 to 80.5 +/- 29 (millilitres per minute per 1.73 m(2)) 3 mo postoperatively.

Conclusions: RAPN is a viable option for nephron-sparing surgery in patients with renal carcinoma. Specifically, in the hands of a surgeon with extensive robotic experience, RAPN requires a short learning curve to reach WIT < 20 min, console times < 100 min, limited blood loss, and acceptable overall complication rates.