CLAMPLESS ROBOT-ASSISTED RENAL TUMORAL ENUCLEATION: INTRA AND POSTOPERATIVE IMPLICATIONS OF CONTROLLED HYPOTENSION
The most important limitation to nephron sparing surgery (NSS) is usually represented by renal ischemia. Since the introduction of NSS techniques several approaches had been applied (cold ischemia, early declamping of renal hilum, selective arterial branches clamp, superselective clamping, preoperative embolization of tumoral arterial branches) to avoid or to reduce renal ischemia. In literature it is widely demonstrated the need of keeping down renal ischemia under 20-30 minutes to reduce the risk of irreversible damage to renal parechyma. The aim of this study is to evaluate the feasibility and safety of robotic-assisted renal tumoral enucleation (RTE) with controlled hypotensive anesthesia to avoid hilar clamping and eliminate renal ischemia.
Methods and results
From April 2011 to January 2014 65 consecutive patients underwent robotic surgery for clinically localized renal cancer. Overall 61/65 patients presented no major contraindications to hypotensive anesthesia; mean age (range) was 64 (42-79) years. RTE is usually performed through a transperitoneal approach without renal hylum isolation. Tumoral enucleation is performed by blunt dissection using the natural cleavage plan between the pseudocapsule and renal parenchyma. In postoperative period patients were evaluated by daily physical examination and routine blood tests on day 1 and 3. Additional examinations were performed in selected cases. Mean arterial pressure during controlled hypotension was 66 mmHg (ranging between 62 and 95 mmHg)and hypotension was prolonged meanly for 10.8 (range: 8,5-20,3) minutes. Mean (range) operative time was 98.7 (71-182) minutes with mean blood loss of 150 ml (55-480 ml). No patients required intraoperative blood transfusions. Mean (range) tumor size was 27 (10-68) mm and mean postoperative hospital stay was 3.1 (2-10) days. Overall 3 patients developed postoperative complications: 1 anemization treated by blood transfusions and 2 delayed canalization that required nasogastric tube insertion. No patients developed major medical complication (syncope, heart failure, stroke). In two cases we observed fatigue that regressed on postoperative day 3. Mean (range) pre and postoperative serum creatinine was 1.0 (0.7-2.2) and 1.2 (0.7-2.7) mg/dl respectively (p=0.487); mean estimated pre and postoperative glomerular filtration rate were 85.9 and 75.2 ml/minute/1.73m2. At histopathological evaluation it was found no positive surgical margins; in only 2 cases it was discovered a peritumoral pseudocapsule incision.
In literature it is widely demonstrated the need of minimizing ischemia during nephron sparing surgery for renal tumors. Controlled hypotension may be an alternative to warm ischemia with renal hilar clamping or to superselective clamping of arterial branches. Robotic assisted zero ischemia tumoral enucleation technique is a reasonable approach to renal tumours irrespective to dimensions. Moreover, in our series, avoiding hilar clamping did not increase the intra and postoperative complication rate and provided excellent functional outcomes. The limit of this study is that available data are not adequately mature to determine long-term functional outcomes and further experience and follow-up is mandatory.Argomenti: cancro del rene