Functional recovery after partial nephrectomy: next generation analysis.

OBJECTIVES: To provide a more rigorous assessment of factors affecting functional recovery after partial nephrectomy (PN) using novel tools that allow for analysis of more patients and improved accuracy for assessment of parenchymal volume loss, thereby revealing the potential impact of secondary factors such as ischaemia. PATIENTS AND METHODS: Of 1140 patients managed with PN (2012-2014), 670 (59%) had imaging and serum creatinine levels measured before and after PN necessary for inclusion. Recovery from ischaemia was defined as the ipsilateral glomerular filtration rate (GFR) saved normalised by parenchymal volume saved. Acute kidney injury was assessed through Spectrum Score, which quantifies the degree of acute ipsilateral renal dysfunction due to exposure to ischaemia that would otherwise be masked by the contralateral kidney. Multivariable regression was used to identify predictors of Spectrum Score and Recovery from Ischaemia. RESULTS: In all, 409/189/72 patients had warm/cold/zero ischaemia, respectively, with median (interquartile range [IQR]) ischaemia times for cold and warm ischaemia of 30 (25-42) and 22 (18-28) min, respectively. The median (IQR) global preoperative GFR and new baseline GFR (NBGFR) were 78 (63-92) and 69 (54-81) mL/min/1.73 m2 , respectively. The median (IQR) ipsilateral preoperative GFR and NBGFR were 40 (33-47) and 31 (24-38) mL/min/1.73 m2 , respectively. Functional recovery correlated strongly with parenchymal volume preserved (r = 0.83, P < 0.01). The median (IQR) decline in ipsilateral GFR associated with PN was 7.8 (4.5-12) mL/min/1.73 m2 with loss of parenchyma accounting for 81% of this loss. The median (IQR) recovery from ischaemia was similar across the cold/warm/zero ischaemia groups at 96% (90%-102%), 95% (89%-101%), and 97% (91%-102%), respectively. Independent predictors of Spectrum Score were ischaemia time, tumour complexity, and preoperative global GFR. Independent predictors of recovery from ischaemia were insulin-dependent diabetes mellitus, refractory hypertension, warm ischaemia, and Spectrum Score. CONCLUSIONS: The main determinant of functional recovery after PN is parenchymal volume preservation. A more robust and rigorous evaluation allowed us to identify secondary factors including comorbidities, increased tumour complexity, and ischaemia-related factors that are also independently associated with impaired recovery, although altogether these were much less impactful.

Complications of single-port robot-assisted radical prostatectomy: multi-institutional analysis from the Single-Port Advanced Research Consortium (SPARC).

OBJECTIVE: To evaluate the perioperative complications of single-port robot-assisted radical prostatectomy (SP-RARP). PATIENTS AND METHODS: A retrospective review was performed on the prospectively maintained, Institutional Review Board-approved, multi-institutional Single-Port Advanced Research Consortium (SPARC) database. A total of 1103 patients were identified who underwent three different approaches of SP-RARP between 2019 and 2022 using the purpose-built SP robotic platform. In addition to baseline clinical, perioperative outcomes, this study comprehensively analysed for any evidence of intraoperative complication, as well as postoperative complication and readmission within 90 days of the respective surgery. RESULTS: Of the 244, 712, and 147 patients who underwent transperitoneal, extraperitoneal, and transvesical SP-RARP, respectively, intraoperative complications were noted in five patients (0.4%), all of which occurred during the transperitoneal approach. Two patients had bowel serosal tears, two had posterior button-holing of the bladder necessitating repair, and one patient had an obturator nerve injury. Postoperative complications were noted in 143 patients (13%) with major complications (Clavien-Dindo Grade ≥III) only identified in 3.7% of the total cohort. The most common complications were lymphocele (3.9%), acute urinary retention (2%), and urinary tract infection (1.9%). The 90-day re-admission rate was 3.9%. CONCLUSION: The SP-RARP is a safe and effective procedure with low complication and readmission rates regardless of the approach. These results are comparable to current multi-port RARP literature.

Robot-assisted surgery for benign distal ureteral strictures: step-by-step technique using the SP® surgical system.

OBJECTIVES: To describe the step-by-step techniques for robot-assisted ureteric reimplantation performed using the Vinci SP® surgical system (Intuitive Surgical, Sunnyvale, CA, USA), including different case scenarios with an educational purpose. MATERIALS AND METHODS: Three consecutive patients diagnosed with distal benign ureteric strictures were counselled for ureteric reimplantation and consented to undergo surgery performed using the da Vinci SP surgical system. Demographics and peri-operative outcomes were collected after institutional review board approval (IRB 13-780). Patients provided informed consent having received an explanation for the adoption of the novel platform. The first patient was a woman referred to our institution for a left distal ureteric stricture after total hysterectomy for uterine fibroids with ureteric injury. The second patient was a man with BPH and recurrent UTIs, who was diagnosed with a 1.5-cm bladder stone and a large bladder diverticulum compressing the left distal ureter. The third patient was a man diagnosed with bilateral uretero-enteric anastomoses stricture status after radical cystectomy with orthotopic ileal neobladder urinary diversion for bladder cancer. RESULTS: The procedures were successfully completed. An extra port through a separate skin incision for the bedside assistant was placed for the first two procedures. In such cases, this additional port was used electively from the start of the procedure and did not represent a change in the treatment plan. Moreover, the port wound was used to accommodate the drainage. The bilateral ureteric reimplantation, however, was completed according to a pure single-site approach (no extra ports were placed out of the GelSeal cap). The mean operating times were 165, 150 and 180 min, respectively. Blood loss was 50 mL in all cases. No intra-operative complications occurred. Patients were discharged on postoperative days 1, 1 and 2, respectively, with normal serum creatinine levels. Neither transfusions nor major complications occurred. CONCLUSION: Robot-assisted reconstructive surgery for benign distal ureteric strictures is feasible and safe using the da Vinci SP surgical system.

Preoperative proteinuria is associated with increased rates of acute kidney injury after partial nephrectomy.

PURPOSE: We investigated the association between preoperative proteinuria and early postoperative renal function after robotic partial nephrectomy (RPN). PATIENTS AND METHODS: We retrospectively reviewed 1121 consecutive RPN cases at a single academic center from 2006 to 2016. Patients without pre-existing CKD (eGFR≥60 mL/min/1.73m2) who had a urinalysis within 1-month prior to RPN were included. The cohort was categorized by the presence or absence of preoperative proteinuria (trace or greater (≥1+) urine dipstick), and groups were compared in terms of clinical and functional outcomes. The incidence of acute kidney injury (AKI) was assessed using RIFLE criteria. Univariate and multivariable models were used to identify factors associated with postoperative AKI. RESULTS: Of 947 patients, 97 (10.5%) had preoperative proteinuria. Characteristics associated with preoperative proteinuria included non-white race (p<0.01), preoperative diabetes (p<0.01) and hypertension (HTN) (p<0.01), higher ASA (p<0.01), higher BMI (p<0.01), and higher Charlson score (p<0.01). The incidence of AKI was higher in patients with preoperative proteinuria (10.3% vs. 4.6%, p=0.01). The median eGFR preservation measured within one month after surgery was lower (83.6% vs. 91%, p=0.04) in those with proteinuria; however, there were no significant differences by 3 months after surgery or last follow-up visit. Independent predictors of AKI were high BMI (p<0.01), longer ischemia time (p<0.01), and preoperative proteinuria (p=0.04). CONCLUSION: Preoperative proteinuria by urine dipstick is an independent predictor of postoperative AKI after RPN. This test may be used to identify patients, especially those without overt CKD, who are at increased risk for developing AKI after RPN.

Robot-assisted transvesical partial prostatectomy using a purpose-built single-port robotic system.

OBJECTIVES: To evaluate the feasibility of robot-assisted single-port (SP) transvesical partial prostatectomy (TVPP) using a novel purpose-built SP surgical platform in a pre-clinical model. METHODS: The cadavers were placed in the lithotomy position. A 3-cm midline incision was made in the suprapubic area 4-cm from the symphisis pubis. After opening the Retzius space, an access mini device (GelPOINT; Applied Medical, Rancho Margarita, CA, USA) was introduced percutaneously directly into the bladder. The da Vinci SP1098 robotic platform (Intuitive Surgical, Sunnyvale, CA, USA) was docked to the GelPOINT by inserting a novel SP cannula through the GelSeal Cap. The surgical steps for en bloc anterior prostatectomy were performed in the following order: (i) antegrade dissection of the transition zone at the bladder neck; (ii) lateral excision of the peripheral zone; and (iii) urethrovesical anastomosis. Primary outcomes, such as intra-operative complications, rate of conversion to standard techniques and operating times, were recorded. RESULTS: The SP-TVPP procedure was technically completed in three male cadavers. All cases were completed successfully using the da Vinci SP1098 surgical system without conversion or the need for additional ports. There were no intra-operative complications. The mean total operating time was 49.3 min. CONCLUSION: Robot-assisted TVPP is feasible using a novel purpose-built SP surgical platform in a cadaver model. Future clinical evaluation in humans is needed for assessment on patients with anterior localized prostate cancer. Prospective comparison with other surgical platforms and standard techniques is warranted.

Patterns and Predictors of Recurrence after Partial Nephrectomy for Kidney Tumors.

PURPOSE: We sought to identify patterns and predictors of recurrence in patients with clinically localized renal cell carcinoma managed by partial nephrectomy. MATERIALS AND METHODS: We performed a retrospective study of 830 consecutive cases of partial nephrectomy done between 2007 and 2015 for clinically localized renal cell carcinoma at a single institution. Patient demographics and pathological characteristics were correlated with recurrence patterns (overall, local and distant) and overall survival using Kaplan-Meier and Cox regression analyses. Differences in the recurrence patterns were evaluated. RESULTS: Median patient age was 61 years and median tumor size was 3.1 cm. Overall, 11.6% of tumors were stage pT3, 39.3% were high grade, 2.9% had lymphovascular invasion and 7.1% had positive margins. Higher grade, higher stage, positive surgical margins and increased R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of deepest tumor portion to collecting system or sinus, anterior/posterior and location relative to polar line) score were associated with shorter disease-free survival on Kaplan-Meier analysis. On multivariable regression pT (p <0.01), grade (p <0.01) and R.E.N.A.L. score (p = 0.03) remained independent predictors of disease-free survival. Predictors of metastasis were pT stage (HR 4.5) and grade (HR 3.9, both p <0.01), while R.E.N.A.L. score (HR 3.2, p = 0.03) was the single predictor of local recurrence. Five-year disease-free and overall survival probabilities were 91% and 94%, respectively. Local recurrence manifested and developed earlier than metastasis (median 13 vs 22 months, p <0.01). CONCLUSIONS: High pT stage, high grade and high R.E.N.A.L. score increase the risk of disease recurrence after partial nephrectomy. The pT stage and grade are predictors of metastasis, while R.E.N.A.L. score predicts local recurrence. Because relapse features and risk factors differ between the 2 recurrence patterns, they should be studied separately in the future.

When Partial Nephrectomy is Unsuccessful: Understanding the Reasons for Conversion from Robotic Partial to Radical Nephrectomy at a Tertiary Referral Center.

PURPOSE: We sought to identify the preoperative factors associated with conversion from robotic partial nephrectomy to radical nephrectomy. We report the incidence of this event. MATERIALS AND METHODS: Using our institutional review board approved database, we abstracted data on 1,023 robotic partial nephrectomies performed at our center between 2010 and 2015. Standard and converted cases were compared in terms of patients and tumor characteristics, and perioperative, functional and oncologic outcomes. Logistic regression analysis was done to identify predictors of radical conversion. RESULTS: The overall conversion rate was 3.1% (32 of 1,023 cases). The most common reasons for conversion were tumor involvement of hilar structures (8 cases or 25%), failure to achieve negative margins on frozen section (7 or 21.8%), suspicion of advanced disease (5 or 15.6%) and failure to progress (5 or 15.6%). Patients requiring conversion were older and had a higher Charlson score (both p <0.01), including an increased prevalence of chronic kidney disease (p = 0.02). Increasing tumor size (5 vs 3.1 cm, p <0.01) and R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of tumor to collecting system or sinus, anterior/posterior, location relative to polar lines and hilar location) score (9 vs 8, p <0.01) were also associated with an increased risk of conversion. Worse baseline renal function (OR 0.98, 95% CI 0.96-0.99, p = 0.04), large tumor size (OR 1.44, 95% CI 1.22-1.7, p <0.01) and increasing R.E.N.A.L. score (p = 0.02) were independent predictors of conversion. Compared to converted cases, at latest followup standard robotic partial nephrectomy cases had similar short-term oncologic outcomes but better renal functional preservation (p <0.01). CONCLUSIONS: At a high volume center the rate of robotic partial nephrectomy conversion to radical nephrectomy was 3.1%, including 2.2% of preoperatively anticipated nephrectomy cases. Increasing tumor size and complexity, and poor preoperative renal function are the main predictors of conversion.

Robotic radical perineal cystectomy and extended pelvic lymphadenectomy: initial investigation using a purpose-built single-port robotic system.

OBJECTIVES: To assess the feasibility of radical perineal cystoprostatectomy using the latest generation purpose-built single-port robotic surgical system. MATERIALS AND METHODS: In two male cadavers the da Vinci® SP1098 Surgical System (Intuitive Surgical, Sunnyvale, CA, USA) was used to perform radical perineal cystoprostatectomy and bilateral extended pelvic lymph node dissection (ePLND). New features in this model include enhanced high-definition three-dimensional optics, improved instrument manoeuvrability, and a real-time instrument tracking and guidance system. The surgery was accomplished through a 3-cm perineal incision via a novel robotic single-port system, which accommodates three double-jointed articulating robotic instruments, an articulating camera, and an accessory laparoscopic instrument. The primary outcomes were technical feasibility, intraoperative complications, and total robotic operative time. RESULTS: The cases were completed successfully without conversion. There were no accidental punctures or lacerations. The robotic operative times were 197 and 202 min. CONCLUSIONS: In this preclinical model, robotic radical perineal cystoprostatectomy and ePLND was feasible using the SP1098 robotic platform. Further investigation is needed to assess the feasibility of urinary diversion using this novel approach and new technology.

Optimum outcome achievement in partial nephrectomy for T1 renal masses: a contemporary analysis of open and robot-assisted cases.

OBJECTIVES: To compare optimum outcome achievement in open partial nephrectomy (OPN) with that in robot-assisted partial nephrectomy (RAPN). PATIENTS AND METHODS: Using our institutional partial nephrectomy (PN) database, we reviewed 605 cases performed for unifocal clinical T1 renal masses in non-solitary kidneys between 2011 and 2015. Tetrafecta, which was defined as negative surgical margins, freedom from peri-operative complications, ≥80% renal function preservation, and no chronic kidney disease upstaging, was chosen as the composite optimum outcome. Factors associated with tetrafecta achievement were assessed using multivariable logistic regression, with adjustment for age, gender, race, Charlson comorbidity score, body mass index, chronic kidney disease, tumour size, tumour complexity and approach. RESULTS: The overall tetrafecta achievement rate was 38%. Negative margins, freedom from complications, and optimum functional preservation were achieved in 97.1%, 73.6% and 54.2% of cases, respectively. For T1a masses, the tetrafecta achievement rate was similar between approaches (P = 0.97), but for T1b masses, the robot-assisted approach achieved significantly higher tetrafecta rates (43.0% vs 21.3%; P < 0.01). On multivariable analysis, the robot-assisted approach had 2.6-fold higher odds of tetrafecta achievement than the open approach, primarily because of lower peri-operative morbidity, specifically related to wound complications. Positive surgical margin rates and renal function preservation were similar in the two approaches. CONCLUSIONS: Optimum outcomes are readily achieved regardless of PN approach. The robot-assisted approach may facilitate optimum outcome achievement for 4-7-cm masses by minimizing wound complications.

Robot-assisted approach improves surgical outcomes in obese patients undergoing partial nephrectomy.

OBJECTIVES: To assess the impact of approach on surgical outcomes in otherwise healthy obese patients undergoing partial nephrectomy for small renal masses. PATIENTS AND METHODS: Using our institutional partial nephrectomy database, we abstracted data on otherwise healthy (Charlson comorbidity score ≤1 and bilateral kidneys), obese patients (body mass index >30 kg/m2 ) with small renal masses (<4 cm) treated between 2011 and 2015. The primary outcomes were intra-operative transfusion, operating time, length of hospital stay (LOS), and postoperative complications. The association between approach, open (OPN) vs robot-assisted partial nephrectomy (RAPN), and outcomes was assessed by univariable and multivariable logistic regression analyses. Covariates included age, gender, obesity severity, tumour size and tumour complexity. RESULTS: Of 237 obese patients undergoing partial nephrectomy, 25% underwent OPN and 75% underwent RAPN. Apart from larger tumour size in the OPN group (2.8 vs 2.5 cm; P = 0.02), there was no significant difference between groups. The rate of intra-operative blood transfusion (1.1 vs 10%; P = 0.01), the median operating time (180 vs 207 min; P < 0.01) and the median ischaemia time (19.5 vs 27 min; P < 0.01) were all greater for OPN. The LOS was significantly shorter for RAPN (3 vs 4 days; P < 0.01). While the overall complication rate was higher for OPN (15.8 vs 31.7%; P < 0.01), major complications were not significantly different (5.6 vs 1.7%; P = 0.20). On multivariable analyses, OPN independently predicted longer operating time, longer length of stay, and more overall complications. CONCLUSIONS: At a high-volume centre, the robot-assisted approach offers less blood transfusion, shorter operating time, faster recovery, and fewer peri-operative complications compared with the open approach in obese patients undergoing partial nephrectomy for small renal masses. In this setting, RAPN may be a preferable treatment option.

Safety and early effectiveness of robot-assisted partial nephrectomy for large angiomyolipomas.

OBJECTIVE: To evaluate a multicentre series of robot-assisted partial nephrectomy (RAPN) performed for the treatment of large angiomyolipomas (AMLs). PATIENTS AND METHODS: Between 2005 and 2016, 40 patients with large or symptomatic AMLs underwent RAPN at five academic centres in the USA. Patient demographics, AML characteristics, operative and postoperative clinical outcomes were recorded and analysed. Surgical outcomes were compared between patients who underwent selective arterial embolisation (SAE) before RAPN and patients who did not undergo pre-RAPN SAE. RESULTS: The median (interquartile range [IQR]) tumour diameter was 7.2 (5-8.5) cm, and the median (IQR) nephrometry score was 9 (7-10). Six patients (15%) had a history of tuberous sclerosis and 11 (28%) had previously undergone SAE. The median (IQR) operative time and warm ischaemia time was 207 (180-231) and 22.5 (16-28) min, respectively. A non-clamping technique was used in eight (20%) patients. The median (IQR) estimated blood loss was 200 (100-245) mL, and four patients (10%) received blood transfusion postoperatively. One intraoperative complication occurred (2.5%), and seven postoperative complications occurred in six patients (15%). During a median (IQR) follow-up of 8 (1-15) months, none of the patients developed AML-related symptoms. The median estimated glomerular filtration rate preservation rate was 95%. There were no differences in operative or perioperative outcomes between patients who underwent SAE before RAPN and those who did not. CONCLUSIONS: Robot-assisted partial nephrectomy appears to be a safe primary or secondary (post-SAE) treatment for large AMLs, with a favourable perioperative morbidity profile and excellent functional preservation. Longer follow-up is required to fully evaluate therapeutic efficacy.

Assessing the effects of modality of surgery on postoperative weight loss in patients undergoing partial nephrectomy.

PURPOSE: To compare the early BMI changes postoperatively between patients undergoing open partial nephrectomy (OPN) and robotic partial nephrectomy (RPN). METHODS: Patients undergoing open NSS for a single renal tumor between 2010 and 2013 were retrospectively selected for the study. These patients were matched with RPN patients based on preoperative BMI and tumor R.E.N.A.L nephrometry score (1:1 matching). RESULTS: A total of 568 patients (284 pairs) met our inclusion criteria. The median time to lowest BMI was comparable between the OPN and RPN groups (24 vs. 29 days; p = 0.7). The mean BMI preservation was lower for the OPN group (96.8 ± 4.4 vs. 98.1 ± 4.7 %). On multivariable analysis after controlling for age, CCI, gender, tumor size, nephrometry score, estimated blood loss, occurrence of major complications and preoperative renal function, the modality of surgery favoring the RPN approach and the occurrence of major complications remained significant predictors for BMI preservation after surgery. CONCLUSIONS: Occurrence of major complications is associated with weight loss after NSS. Minimally invasive NSS delivered by RPN had lower impact on BMI loss in patients undergoing the procedure compared to OPN. This finding further suggests that RPN delivers minimally invasive surgery beyond the boundaries of just smaller incision sites.

Robotic and open partial nephrectomy for localized renal tumors larger than 7 cm: a single-center experience.

PURPOSE: To compare perioperative outcomes between robotic partial nephrectomy and open partial nephrectomy for localized >7 cm tumors. METHODS: We identified patients in our institutional review boards approved database who underwent robotic partial nephrectomy or open partial nephrectomy for treatment of renal tumors >7 cm in size between January 2009 and August 2015. The operative-postoperative outcomes and complications were compared between groups. RESULTS: The number of patients with >7 cm renal tumors treated at our center with robotic partial nephrectomy and open partial nephrectomy were 54 and 56, respectively. Patients' demographics and tumor characteristics were similar between groups. Likewise, there were no significant difference between the groups in duration of operation, positive surgical margin rates and incidence of malignant disease rates. Median ischemia time was lower in robotic partial nephrectomy group (31.5 vs. 35 min., p = 0.02). Patients undergoing robotic partial nephrectomy had significantly lower intraoperative blood transfusion rates (9.4 vs. 30.4 %, p = 0.008) and shorter length of hospital stay (3.5 vs. 5.3 days, p < 0.001). The incidence of overall complications (robotic arm, 18.5 % vs. open arm, 28.6 %, p = 0.26) and major complications (robotic arm, 3.7 % vs. open arm, 12.5 %, p = 0.16) was comparable between the two groups. The readmission rate within 30-days after discharge was higher in open partial nephrectomy group (p = 0.03). There was no difference in the median percentage estimated glomerular filtration rate preservation and chronic kidney disease upstaging between groups. CONCLUSIONS: Localized renal tumors >7 cm and amenable to partial nephrectomy can be considered suitable for robotic approach.

Robot-assisted ureteral reconstruction using a tubularized peritoneal flap: a novel technique in a chronic porcine model.

OBJECTIVE: To evaluate the feasibility and functional outcomes in porcine models of a novel robotic surgical technique for the treatment of complex ureteral injuries and strictures. MATERIALS AND METHODS: Six pigs underwent robotic ureteral reconstruction using a long tabularized peritoneal flap and followed for 6-9 weeks after the surgery. Ureteral flap vascularity, intra-renal pressure, patency of the conduct, endoscopic aspect of the flap, renal function and histopathology were evaluated. RESULTS: All animals successfully underwent ureteral reconstruction using a tubularized peritoneal flap. Median operative time was 223 min (162-360). Flap tubularization suture took 31 min (19-47), and proximal anastomosis took 20 min (15-38). Bladder mobilization with psoas hitch and distal anastomosis took 9 min (7-12) and 23 min (13-46), respectively. On follow-up, significant shrinkage of the ureteral flap in both length and width was observed. Antegrade pyelograms confirmed dilation and tortuosity of the proximal ureter, dilation of the renal pelvis, and major and minor calyxes without any definitive strictures. Microscopically, focal urothelial lining was seen in the neoureter. Creatinine level was significantly higher at the end of the follow-up period (p = 0.003). CONCLUSIONS: Robot-assisted ureteral reconstruction using a tubularized peritoneum flap is technically feasible and reproducible. The flap sustained abundant vascular supply after different intervals of follow-up and the peritoneal mesenchymal cells differentiated into urothelium and myofibroblasts. Further studies are needed to address the issue of functional obstruction to improve long-term renal function outcomes.

Risks and Benefits of Pharmacological Prophylaxis for Venous Thromboembolism Prevention in Patients Undergoing Robotic Partial Nephrectomy.

PURPOSE: We investigate the safety and efficacy of pharmacological venous thromboembolism prophylaxis in patients treated with robotic partial nephrectomy at our center. MATERIALS AND METHODS: We retrospectively examined our robotic partial nephrectomy database for cases performed between 2006 and 2014. Clinical venous thromboembolism episodes within 6 months from surgery were documented. Patients were stratified according to the administration of pharmacological venous thromboembolism prophylaxis into pharmacological prophylaxis (222) and no pharmacological prophylaxis (762) groups. The groups were compared in terms of perioperative outcomes, complications and adverse hemorrhagic events defined as the administration of 2 or more units of red blood cells, the need for vascular embolization or any procedures related to blood loss. RESULTS: There were no differences between the pharmacological prophylaxis and no pharmacological prophylaxis groups regarding mean operation time, median warm ischemia time and estimated blood loss. The rates of venous thromboembolism events were comparable between the groups (pharmacological prophylaxis 1.8% vs no pharmacological prophylaxis 2.1%, p=0.75). Overall 90% of venous thromboembolism events occurred within the first postoperative month. In the multivariable regression analysis encompassing pharmacological prophylaxis, perioperative aspirin intake, body mass index, operation time, Charlson comorbidity index, fellowship training and tumor complexity, operation time (OR 1.06, p=0.009) and Charlson comorbidity index (OR 1.28, p <0.0001) were associated with adverse hemorrhagic events. CONCLUSIONS: The administration of pharmacological prophylaxis did not increase the rate of adverse hemorrhagic events. Isolated inpatient administration of pharmacological prophylaxis after robotic partial nephrectomy does not appear to protect against venous thromboembolism postoperatively in that the majority of venous thromboembolism events occurred within the first 30 days after surgery. Longer duration of pharmacological prophylaxis for the prevention of venous thromboembolism after robotic partial nephrectomy should be considered.

Robotic perineal radical prostatectomy and pelvic lymph node dissection using a purpose-built single-port robotic platform.

OBJECTIVES: To describe the features of the novel, purpose-built da Vinci model SP1098 single-port robotic platform and to describe a step-by-step approach for perineal prostatectomy and pelvic lymph node dissection in a cadaver model. METHODS: Three single-port robotic radical perineal prostatectomies and two pelvic lymph node dissections were performed on three male cadavers to assess the feasibility of the SP1098 da Vinci robotic platform. The steps in the procedure included division of the rectourethralis muscle, splitting of the levator ani muscles bilaterally, opening of Denonvilliers fascia with dissection of the seminal vesicles, apical dissection and urethral division, anterior and lateral dissection with ligation of prostatic pedicles, bilateral pelvic lymph node dissection, and creation of the new vesico-urethral anastomosis. The main outcomes assessed were operating time per step, total operating time, intra-operative complications and need for conversion to conventional or open techniques. RESULTS: No conversions were required. No intra-operative complications were seen. The median (range) operating time for performing single-port robotic radical perineal prostatectomy and pelvic lymph node dissection was 210 (180-240) min. CONCLUSIONS: We have shown the feasibility and efficacy of a novel, purpose-built robotic system in performing single-port radical perineal prostatectomy and describe, for the first time, the feasibility of robotic perineal lymph node dissection. This single-port system will facilitate single-port applications and allow surgeons to perform major urological operations via a small, single incision while preserving triangulation and optics, and eliminating clashing between instruments. Future clinical studies are needed to support these encouraging outcomes.

Robot-assisted partial nephrectomy with intracorporeal renal hypothermia using ice slush: step-by-step technique and matched comparison with warm ischaemia.

OBJECTIVES: To outline our step-by-step technique for intracorporeal renal cooling during robot-assisted partial nephrectomy (RAPN). PATIENTS AND METHODS: Patient selection was performed during a preoperative clinic visit. Cases where we estimated during preoperative assessment that warm ischaemia time would be >30 min, as determined by whether the patient had a complex renal mass, were selected. The special equipment required for this procedure includes an Ecolab Hush Slush machine (Microtek Medical Inc., Columbus, MS, USA) a Mon-a-therm needle thermocouple device (Covidien, Mansfield, MA, USA) and six modified 20-mL syringes. Patients are arranged in a 60° modified flank position with the operating table flexed slightly at the level of the anterior superior iliac spine. For the introduction of a temperature probe and ice slush, an additional 12-mm trocar is placed along the mid-axillary line beneath the costal margin. Modified 10/20 mL syringes are prefilled with ice slush for instillation via an accessory trocar. Peri-operative and 6-month functional outcomes in the cold ischaemia group were compared with those of a cohort of patients who underwent RAPN with warm ischaemia in a 2:1 matched fashion. Matching was performed based on preoperative estimated glomerular filtration rate (GFR), ischaemia time and RENAL nephrometry score. RESULTS: Strategies for successful intracorporeal renal cooling include: (i) placement of accessory port directly over the kidney; (ii) uniform ice consistency and modified syringes; (iii) sequential clamping of renal artery and vein; (iv) protection of the neighbouring intestine with a laparoscopic sponge; and (v) complete mobilization of the kidney. Kidney temperature is monitored via a needle thermocoupler device, while core body temperature is concurrently monitored via an oesophageal probe in real time. Renal function was assessed by serum creatinine level, estimated GFR (eGFR) and mercaptoacetyltriglycine (MAG-3) renal scan, peri-operatively and at 6-month follow-up. In the separate matched analysis, cold ischaemia during RAPN was found to be associated with a 12.9% improvement in preservation of postoperative eGFR. No difference was seen in either group at 6-month follow-up. CONCLUSIONS: We conclude that RAPN with intracorporeal renal hypothermia using ice slush is technically feasible and may improve postoperative renal function in the short term. Our technique for intracorporeal hypotheramia is cost-effective, simple and highly reproducible.

Predicting complications in partial nephrectomy for T1a tumours: does approach matter?

OBJECTIVES: To assess differences in complications after robot-assisted (RAPN) and open partial nephrectomy (OPN) among experienced surgeons. PATIENTS AND METHODS: We identified patients in our institutional review board-approved, prospectively maintained database who underwent OPN or RAPN for management of unifocal, T1a renal tumours at our institution between January 2011 and August 2015. The primary outcome measure was the rate of 30-day overall postoperative complications. Baseline patient factors, tumour characteristics and peri-operative factors, including approach, were evaluated to assess the risk of complications. RESULTS: Patients who underwent OPN were found to have a higher rate of overall complications (30.3% vs 18.2%; P = 0.038), with wound complications accounting for the majority of these events (11.8% vs 1.8%; P < 0.001). Multivariable logistic regression analysis showed the open approach to be an independent predictor of overall complications (odds ratio 1.58, 95% confidence interval 1.03-2.43; P = 0.035). Major limitations of the study include its retrospective design and potential lack of generalizability. CONCLUSIONS: The open surgical approach predicts a higher rate of overall complications after partial nephrectomy for unifocal, T1a renal tumours. For experienced surgeons, the morbidity associated with nephron-sparing surgery may be incrementally improved using the robot-assisted approach.

Comparison of robot-assisted and open partial nephrectomy for completely endophytic renal tumours: a single centre experience.

OBJECTIVE: To compare outcomes between robot-assisted partial nephrectomy (RAPN) and open PN (OPN) for completely endophytic renal tumours. PATIENTS AND METHODS: We retrospectively reviewed 1 230 consecutive cases, consisting of 823 RAPNs and 407 OPNs, performed for renal mass at a single academic tertiary centre between 2011 and 2016. Of these, data on 87 RAPN and 56 OPN cases for completely endophytic renal tumours were analysed. Patient and tumour characteristics, operative, postoperative, functional, and oncological outcomes were compared between groups. RESULTS: Apart from a higher prevalence of solitary kidney among OPN cases (RAPN, 5.7% vs OPN, 21.4%; P = 0.005), demographic characteristics were similar between the groups. There were no statistically significant differences in tumour size (P = 0.07), tumour stage (P = 0.3), margin status (P = 0.48), malignant tumour subtypes (P = 0.51), and grades (P = 0.61) between the groups. Also, there were no statistically significant differences among the groups for warm ischaemia time (P = 0.15), cold ischaemia time (P = 0.28), and intraoperative (P = 0.75) or postoperative (Clavien-Dindo Grade I-V, P = 0.08; Clavien-Dindo Grade III-V, P = 0.85) complication rates. The patients in the RAPN group had a shorter length of stay (P < 0.001), less estimated blood loss (P < 0.001), and lower intraoperative transfusion rates (0% vs 7.1%, P = 0.02). No local recurrences occurred during a median (interquartile range) follow-up of 15.2 (7-27.2) and 18.1 (8.2-30.9) months in the RAPN and OPN groups, respectively. There was no difference in estimated glomerular filtration rate preservation rates between groups for the early (P = 0.26) and latest (P = 0.22) functional follow-up. CONCLUSION: For completely endophytic renal tumours, both OPN and RAPN have excellent outcomes when performed by experienced surgeons at a high-volume centre. For skilled robotic surgeons, RAPN is a safe and effective alternative to OPN with the advantages of shorter length of stay and less blood loss.

Urinary fistula after robot-assisted partial nephrectomy: a multicentre analysis of 1 791 patients.

OBJECTIVE: To evaluate the incidence of and risk factors for a urine leak in a large multicentre, prospective database of robot-assisted partial nephrectomy (RPN). PATIENTS AND METHODS: A database of 1 791 RPN from five USA centres was reviewed for urine leak as a complication of RPN. Patient and tumour characteristics were compared between patients with and those without postoperative urine leaks. Fisher's exact test was used for qualitative variables and Wilcoxon sum-rank tests were used for quantitative variables. A review of the literature on PN and urine leak was conducted. RESULTS: Urine leak was noted in 14/1 791 (0.78%) patients who underwent RPN. The mean (sd) nephrometry score of the entire cohort was 7.2 (1.9), and 8.0 (1.9) in patients who developed urine leak. The median (range) postoperative day of presentation was 13 (3-32) days. Patients with urine leak presented in delayed fashion with fever (two of the 14 patients, 14%), gastrointestinal complaints (four patients, 29%), and pain (five patients, 36%). Eight of the 14 patients (57%) required admission, while eight (57%) and nine (64%) had a drain or stent placed, respectively. Drains and stents were removed after a median (range) of 8 (4-13) days and 21 (8-83) days, respectively. Variables associated with urine leak included tumour size (P = 0.021), hilar location (P = 0.025), operative time (P = 0.006), warm ischaemia time (P = 0.005), and pelvicalyceal repair (P = 0.018). Upon literature review, the historical incidence of urine leak ranged from 1.0% to 17.4% for open PN and 1.6-16.5% for laparoscopic PN. CONCLUSION: The incidence of urine leak after RPN is very low and may be predicted by some preoperative factors, affording better patient counselling of risks. The low urinary leak rate may be attributed to the enhanced visualisation and suturing technique that accompanies the robotic approach.