Ipsilateral renal function preservation after robot-assisted partial nephrectomy (RAPN): an objective analysis using mercapto-acetyltriglycine (MAG3) renal scan data and volumetric assessment.

OBJECTIVE: To objectively assess ipsilateral renal function (IRF) preservation and factors influencing it after robot-assisted partial nephrectomy (RAPN). PATIENTS AND METHODS: Our database was queried to identify patients who had undergone RAPN from 2007 to 2013 and had complete pre- and postoperative mercapto-acetyltriglycine (MAG3) renal scan assessment. The estimated glomerular filtration rate (eGFR) for the operated kidney was calculated by multiplying the percentage of contribution from the renal scan by the total eGFR. IRF preservation was defined as a ratio of the postoperative eGFR for the operated kidney to the preoperative eGFR for the operated kidney. The percentage of total eGFR preservation was calculated in the same manner (postoperative eGFR/preoperative eGFR × 100). The amount of healthy rim of renal parenchyma removed was assessed by deducting the volume of tumour from the volume of the PN specimen assessed on pathology. Multivariable linear regression was used for analysis. RESULTS: In all, 99 patients were included in the analysis. The overall median (interquartile range) total eGFR preservation and IRF preservation for the operated kidney was 83.83 (75.2-94.1)% and 72 (60.3-81)%, respectively (P < 0.01). On multivariable analysis, volume of healthy rim of renal parenchyma removed, warm ischaemia time (WIT) > 30 min, body mass index (BMI) and operated kidney preoperative eGFR were predictive of IRF preservation. CONCLUSIONS: Using total eGFR tends to overestimate the degree of renal function preservation after RAPN. This is particularly relevant when studying factors affecting functional outcomes after nephron-sparing surgery. IRF may be a more precise assessment method in this setting. Operated kidney baseline renal function, BMI, WIT >30 min, and amount of resected healthy renal parenchyma represent the factors with a significant impact on the IRF preservation. RAPN provides significant preservation of renal function as shown by objective assessment criteria.

30-day hospital readmission after robotic partial nephrectomy--are we prepared for Medicare readmission reduction program?

PURPOSE: After CMS introduced the concept of the Hospital Readmissions Reduction Program, hospitals and health care centers became financially penalized for exceeding specific readmission rates. MATERIALS AND METHODS: We retrospectively reviewed our institutional review board approved database of patients undergoing robotic partial nephrectomy at our institution and included in our analysis patients who were readmitted to any hospital as an inpatient stay within 30 days from discharge home after robotic partial nephrectomy. RESULTS: From March 2006 to March 2013 a total of 627 patients underwent robotic partial nephrectomy at our center and 28 (4.46%) were readmitted within 30 days of surgery. Postoperative bleeding was responsible for 8 (28.5%) readmissions. Pulmonary embolism was reported in 3 cases and retroperitoneal abscess was diagnosed in 2. Urinary leak requiring surgical intervention developed in 2 patients, pneumonia was diagnosed in 2 and 2 patients were readmitted for chest pain. Overall 9 (32.1%) patients presented with major complications requiring intervention. On multivariable analysis Charlson comorbidity index score was the only factor significantly associated with a higher 30-day readmission rate (p = 0.03). If the Charlson score was 5 or greater the chance of hospital readmission would be 2.7 times higher. CONCLUSIONS: Increased comorbidity, specifically a Charlson score of 5 or greater, was the only significant predictor of a higher incidence of 30-day readmission. This information can be useful in counseling patients regarding robotic partial nephrectomy and in determining baseline rates if CMS expands the number of conditions they evaluate for excess 30-day readmissions.