Duplex scan and histologic assessment of acute renal injury in a kidney-kidney crosstalk swine experimental model.

OBJECTIVE: The objective of this study was to identify the effect of two left renal vasculature occlusion strategies on the duplex ultrasound-assessed rheology and histology of the contralateral kidney. METHODS: Pigs were randomly assigned to one of two groups: left renal artery-only clamping (A group, n = 8) or left renal artery and vein clamping (AV group, n = 9). Bilateral renal parenchymal biopsy specimens were taken every 10 minutes for 90 minutes. Duplex ultrasound resistive index (RI) and pulsatility index (PI) were measured. Mixed models with normal distribution and first-order autoregressive correlation structure and generalized estimating equation models were used. Results are presented as adjusted means with standard errors, estimated proportions with standard errors, and line plots with 95% confidence intervals. RESULTS: RI and PI increased in the nonischemic kidney. In A group animals, RI values increased significantly (P < .01) after 30 minutes of ischemia and PI increased significantly (P < .04) from 30 to 60 minutes of ischemia. The number of histologic abnormalities was higher in A group than in AV group biopsy specimens. The percentage of lesions increased significantly after 10 minutes in A group nonischemic kidneys (P < .02) and between 50 and 80 minutes in AV group nonischemic kidneys (P < .01). CONCLUSIONS: Nonischemic kidneys were acutely affected by contralateral ischemia. Their function was more adversely affected by unilateral renal artery occlusion with preserved renal vein patency (A group).

Robotic radical anterior pelvic exenteration: the UCI experience.

Robotic technology may be a promising tool in reduction of morbidity in radical anterior pelvic exenteration for invasive bladder cancer. We report our initial experience with robotic-assisted radical anterior pelvic exenteration in females in an attempt to evaluate the technique's feasibility and outcomes. A retrospective review of our bladder cancer database was performed. Twelve women that underwent robotic-assisted radical anterior pelvic exenteration, bilateral pelvic lymphadenectomy, and urinary diversion for clinically localized urothelial carcinoma of the bladder between 2004 and 2008 were included in this retrospective study. Median age was 73.0 +/- 9.6 years and median body mass index (BMI) was 23.5 +/- 5.0 kg/m2. Ten patients underwent ileal conduit diversion, one had an orthotopic neobladder and one an Indiana pouch. Median total operating time was 6.4 +/- 1.5 hours with median console and diversion times of 4.7 +/- 0.9 and 2.5 +/- 1.5 hours respectively. Median blood loss was 275.0 +/- 165.8 ml. Median length of stay was 8.0 +/- 1.6 days. Four patients were T2N0 or less, five T3N0, one T3N1 and two patients T4N0. There was one patient with positive surgical margins. Median number of lymph nodes removed was 23.0 +/- 11.4. Median follow-up of 9.0 +/- 6.0 months was available for ten patients. One had a recurrent ureteroenteric stricture, one had colpocleisis for vault prolapse, and three had metastatic disease. Robotic-assisted laparoscopic anterior pelvic exenteration appears to be a favorable surgical option with acceptable operative, pathological, and short-term clinical outcomes. According to the UCI experience, robotic anterior exenteration appears to achieve the clinical and oncologic goals for the surgical treatment of bladder cancer.

In vitro, ex vivo and in vivo isotherms for renal cryotherapy.

PURPOSE: Preoperative planning for renal cryotherapy is based on isotherms established in gel. We replicated gel isotherms and correlated them with ex vivo and in vivo isotherms in a porcine model. MATERIALS AND METHODS: PERC-17 CryoProbes (1.7 mm) and IceRods (1.47 mm) underwent trials in gel, ex vivo and in vivo porcine kidneys. Temperatures were recorded at 13 predetermined locations with multipoint thermal sensors. RESULTS: At the cryoprobe temperatures were not significantly different along the probe in any medium for either system (p = 0.0947 to 0.9609). However, away from the probe ex vivo and in vivo trials showed warmer temperatures toward the cryoprobe tip for each system (p = 0.0003 to 0.2141). Mean +/- SE temperature 5 mm distal to the cryoprobe tip in vivo was 19.2C +/- 16.1C for CryoProbes and 27.3C +/- 11.2C for IceRods. Temperatures were consistently colder with CryoProbes than with IceRods in gel (p <0.00005), ex vivo (p <0.00005) and in vivo (p = 0.0014). At almost all sites temperatures were significantly colder in gel and in ex vivo kidney than in in vivo kidney for CryoProbes (p = 0.0107 and 0.0008, respectively) and for IceRods (each p <0.00005). CONCLUSIONS: Gel and ex vivo isotherms do not predict the in vivo pattern of freezing. Thus, they should not be used for preoperative planning. The cryoprobe should be passed 5 mm beyond the tumor border to achieve suitably cold temperatures. Multipoint thermal sensor probes are recommended to record actual temperature during renal cryotherapy.

Genitourinary exam skills training curriculum for medical students: a follow-up study of comfort and skill utilization.

PURPOSE: We developed a genitourinary skills training (GUST) curriculum for incoming third year medical students (MS3) and performed a follow-up study of comfort with and utilization of these skills. MATERIALS AND METHODS: GUST consisted of a didactic lecture followed by skills sessions including standardized patient testicular examination (TE) and digital rectal examination (DRE), male and female Foley catheter (MFC and FFC) placement training, suture-knot tying, and a faculty-directed small group learning session. Precourse and postcourse, and 6 and 18 months after the course, MS3 rated comfort with each skill (Likert scale 0-5), and quantified skill usage. Results were compared with 4th year students (MS4) who had not undergone GUST. RESULTS: Participants were 281 MS3 GUST students and 44 MS4. Post-GUST, mean comfort on a Likert scale (0=uncomfortable) increased for all four skills (88.2%-96.9% vs 8.3%-18.5%, P<0.0001). This was maintained at the 6-month and 18-month follow up time points (P<0.0001). At 18 months, MS3 trended toward higher comfort with TE compared with MS4 (74 vs 54%, P=0.068), while with the other skills, both groups showed equal comfort. MS4 learned exam skills from faculty and MFC and FFC from nurses on the wards. Eleven percent of MS4 were never formally taught TE or DRE. MS3 and MS4 performed TE and/or DRE on <8% of newly admitted patients. CONCLUSIONS: MS3 described improved comfort with the GU skills at all time points during follow-up. This was particularly important because both MS3 and MS4 reported using their skills infrequently during their clinical training years.

Are multiple cryoprobes additive or synergistic in renal cryotherapy?

OBJECTIVE: To investigate the relationship between multiple cryoprobes was investigated to determine whether they work in an additive or synergistic fashion in an in vivo animal model because 1.47 mm (17-gauge) cryoprobes have been introduced to the armamentarium for renal cryotherapy. METHODS: Laparoscopic-guided percutaneous cryoablation was performed in both renal poles of 3 pigs using 3 IceRod cryoprobes. These 12 cryolesions were compared with 12 cryolesions using a single IceRod cryoprobe. Each cycle consisted of two 10-minute freeze cycles separated by a 5-minute thaw. The iceball volume was measured using intraoperative ultrasonography. The kidneys were harvested, and cryolesion surface area was calculated. The lesions were fixed and excised to obtain a volume measurement. Statistical analysis was used to compare the single probe results multiplied by 3 to the multiple probe group for iceball volume, cryolesion surface area, and cryolesion volume. RESULTS: The iceball volume for the first freeze cycle for the single cryoprobe multiplied by 3 was 8.55 cm3 compared with 9.79 cm3 for the multiple cryoprobe group (P=.44) and 10.01 cm3 versus 16.58 cm3 for the second freeze (P=.03). The cryolesion volume for the single cryoprobe multiplied by 3 was 11.29 cm3 versus 14.75 cm3 for the multiple cyroprobe group (P=.06). The gross cryolesion surface area for the single cryoprobe multiplied by 3 was 13.14 cm2 versus 13.89 cm2 for the multiple probe group (P=.52). CONCLUSION: The cryolesion created by 3 simultaneously activated 1.47-mm probes appears to be larger than that of an additive effect. The lesions were significantly larger as measured by ultrasonography and nearly so (P=.06) as measured by the gross cryolesion volume.

Impact of pneumoperitoneum on renal cryotherapy.

PURPOSE: Pneumoperitoneum is known to decrease blood flow to the kidney during laparoscopy. We investigated if this change in blood flow would increase the size of the cryolesion. MATERIALS AND METHODS: Twelve Yorkshire swine underwent laparoscopy-guided percutaneous cryoablation of the upper and lower pole of each kidney at four randomized pneumoperitoneum pressures (10, 15, 20, and 25 mm Hg). Cryolesions were made with a 1.47-mm IceRod (Galil Medical, Plymouth Meeting, PA). Each site underwent two 10-minute freeze cycles separated by a 5-minute active thaw with pressurized helium gas. At the conclusion of each freeze cycle, the iceball volume was measured with intraoperative ultrasound. After completion of the four cryolesions, the kidneys were harvested, and the cryolesion surface area was calculated. The lesions were fixed in 10% buffered formalin and then excised with a 1-mm margin to obtain a volume measurement using fluid displacement. RESULTS: Iceball volume was 3.41, 2.85, 3.44, and 2.36 cm(3) for freeze cycle 1 (p = 0.16) and 3.67, 3.34, 4.88, 3.95 cm(3) for freeze cycle 2 (p = 0.20) at 10, 15, 20, and 25 mm Hg, respectively. Cryolesion volume by fluid displacement was 4.06, 3.77, 3.97, and 3.93 cm(3) (p = 0.86) and cryolesion surface area was 4.55, 4.38, 4.39, and 4.20 cm(2) (p = 0.71) at 10, 15, 20, and 25 mm Hg, respectively. CONCLUSIONS: In this study, pneumoperitoneum pressure between 10 and 25 mm Hg did not affect iceball size as measured by intraoperative ultrasound, cryolesion volume by fluid displacement, or cryolesion surface.