Biomedical subjects

Kevin C Zorn

Publications and source records attributed to Kevin C Zorn.

13 recordsLinked to original sources

PubMed2007

Laparoscopic ice slurry coolant for renal hypothermia.

PURPOSE: We assessed the safety and efficacy of microparticulate ice slurry for laparoscopic hypothermia during renal ischemia in a single kidney porcine model. MATERIALS AND METHODS: A total of 18 farm pigs were randomized to 3 groups of 6 each. All groups underwent initial right laparoscopic nephrectomy, followed by 1 of 3 procedures on the left kidney. Group 1 underwent 90-minute hilar clamping under warm ischemia, group 2 underwent 90-minute hilar clamping under cold ischemia using laparoscopically delivered microparticulate ice slurry and control group 3 underwent hilar dissection, no clamping and no microparticulate ice slurry. Body and renal cortical temperatures were measured. Serum creatinine and the glomerular filtration rate were assessed preoperatively, and on postoperative days 1, 3, 8 and 15. RESULTS: Average time to achieve a renal temperature of 20C or less was 9.7 minutes and it remained constant during the 90-minute cold ischemia time. Mean serum creatinine was significantly higher in the warm ischemia group than in the cold ischemia and control groups on postoperative days 1 and 3. Additionally, mean serum creatinine in the cold ischemia and control groups was similar at all time points. The mean glomerular filtration rate was significantly lower in the warm ischemia group than in the cold ischemia and control groups on postoperative days 1, 3 and 8. The mean glomerular filtration rate in the cold ischemia group was lower than in the control group on postoperative day 1, while it was similar on postoperative days 3, 8 and 15. CONCLUSIONS: In the porcine model laparoscopic renal hypothermia achieved with microparticulate ice slurry was safe and efficient. It significantly decreased renal dysfunction secondary to an ischemic insult with no adverse effects or complications associated with microparticulate ice slurry use.

Animals↗

PubMed2006

Robotic-assisted laparoscopic prostatectomy: functional and pathologic outcomes with interfascial nerve preservation.

INTRODUCTION: Robotic-assisted laparoscopic radical prostatectomy (RLRP) is increasingly becoming an alternative to open and laparoscopic radical prostatectomy in the treatment of localized prostate cancer. RLRP has been associated with low morbidity, short convalescence and comparable oncologic and functional outcomes. We report our initial experience of 300 consecutive cases with selective use of interfascial nerve preservation (IFNP). METHODS: Between February 2003 and September 2005, 300 consecutive men underwent RLRP at our institution. Patients were followed prospectively with validated questionnaires. RESULTS: Mean operative time was 282 minutes with an estimated blood loss of 273 ml. The intra-operative complication rate was 2.3% with no mortality. Return to baseline (RTB) urinary function and subjective continence at 12 months were 71% and 90.2%, respectively. RTB sexual function and subjective potency at 12 months were 53% and 80.4%, respectively. Overall, the positive surgical margin (PSM) rate was 20.9%: 15.1% for pT2 and 52.1% for pT3 disease and 93.1% had an undetectable PSA (<0.1 ng/mL) with a mean follow-up of 17.3 months. Fifty-four percent of PSMs occured in a poster-lateral (PL) location. Retrospectively, IFNP was performed in 86.5% and 62.5% of pT2 and pT3 PSMs, respectively. Pathologic-T3 PSMs were found to occur significantly more often in a PL location when ipsilateral IFNP was performed when compared to non-IFNP (73% vs 33%, p=0.05). CONCLUSIONS: IFNP appears to result in favorable return of potency, however, postero-lateral PSMs appear to occur more frequently with this technique. Proper patient selection for robotic surgery and nerve-preservation appears to be critical in order to reduce PSM and optimize the oncologic efficacy of this technology.

Adult↗

PubMed2006

Minimizing knot tying during reconstructive laparoscopic urology.

OBJECTIVES: Intracorporeal knot tying during urologic reconstructive surgery is one of the most technically challenging skills of laparoscopic surgery. We describe our experience using the Lapra-Ty clip to substitute for knot tying. METHODS: Our technique for minimizing knot tying entails the use of the Lapra-Ty clip during closure of the collecting system and renal parenchyma for laparoscopic partial nephrectomy, the vesicourethral anastomosis during robotic laparoscopic radical prostatectomy, and the collecting system during laparoscopic pyeloplasty. From October 2002 to July 2005 at our institution, 75 patients underwent laparoscopic partial nephrectomy, 300 underwent robotic laparoscopic radical prostatectomy, and 14 underwent laparoscopic pyeloplasty. We reviewed the charts retrospectively for intraoperative and postoperative parameters related to the use of these clips. RESULTS: In the laparoscopic partial nephrectomy group, the mean tumor size, warm ischemia time, and estimated blood loss was 2.53 cm, 30.1 minutes, and 189 mL, respectively. Two postoperative urine leaks (2.7%) developed, and 3 patients experienced postoperative bleeding (4%). In the robotic laparoscopic radical prostatectomy group, the mean operative time was 295 minutes and the mean estimated blood loss was 303.6 mL. Only 3 patients had a urine leak (1%), and 4 patients had bladder neck contracture (1.3%). With regard to the laparoscopic pyeloplasty group, the mean operative time and estimated blood loss was 224 minutes and 36 mL, respectively. No intraoperative complications or urinary leaks occurred. CONCLUSIONS: Using the Lapra-Ty clip, we have safely and efficiently supplemented knot tying in patients undergoing reconstructive laparoscopic surgery.

Adult↗

PubMed2006

Open versus laparoscopic simultaneous bilateral adrenalectomy.

OBJECTIVES: To compare our experience with synchronous bilateral adrenalectomy using laparoscopic and open techniques. Laparoscopic adrenalectomy has become the reference standard for management of benign unilateral adrenal pathologic findings. METHODS: This was a nonrandomized retrospective chart review of 12 known patients who underwent simultaneous bilateral adrenalectomy, comparing five laparoscopic and seven open procedures. One urologic surgeon performed all laparoscopic cases, and one general surgeon performed all open procedures. RESULTS: All patients had Cushing's disease or syndrome. The average patient age was 47.4 years (range 24 to 71) and 42.4 years (range 19 to 70), with an average body mass index of 38.2 kg/m2 and 36.0 kg/m2 for the laparoscopic and open groups, respectively. The operating time was on average 60 minutes longer for the laparoscopic group. No open conversions were necessary. The median blood loss (100 versus 500 mL, P < 0.01) and hematocrit drop (8.5% versus 12.6%, P = 0.05) were lower for the laparoscopic group. The transfusion rates and hospital stay trended lower in the laparoscopic group (20% versus 57% and 3 versus 8.5 days, respectively). Specimen weights for both the right and left glands trended larger for the laparoscopic group. The complication rates were similar between groups at 60% for the laparoscopic versus 71% for the open groups. CONCLUSIONS: Simultaneous laparoscopic bilateral adrenalectomy is safe and effective. Compared with the open approach, it resulted in decreased blood loss, lower transfusion rate, and a trend toward a shorter hospital stay, although the operating time was longer. The laparoscopic approach should be the treatment of choice for bilateral adrenalectomy.

Adrenalectomy↗

PubMed2006

Robotic-assisted laparoscopic prostatectomy in overweight and obese patients.

OBJECTIVES: To assess outcomes of robotic laparoscopic radical prostatectomy (RLRP) in overweight and obese patients, defined as those with a body mass index (BMI) of 25 to 30 kg/m2 and greater than 30 kg/m2, respectively. METHODS: This was a nonrandomized study evaluating all of our RLRP patients. Patients were divided into three groups: BMI of 25 kg/m2 or less (group 1), BMI greater than 25 kg/m2 and less than 30 kg/m2 (group 2), and BMI of 30 kg/m2 or more (group 3). Patients were evaluated prospectively with the validated Rand 36-Item Health Survey (version 2) and with the University of California, Los Angeles Prostate Cancer Index questionnaire. RESULTS: Between February 2003 and November 2004, 150 RLRPs were performed at our center. Average follow-up was 8 months. Groups 1, 2, and 3 had 39, 65, and 46 patients, respectively. Average BMIs for all three groups were statistically different (P < 0.01). When compared with group 1, open conversion rates, hospital stay, positive margin, and complication rates were not statistically different for groups 2 or 3. Operative time (P < 0.004) and estimated blood loss (P < 0.03), however, were statistically greater for group 3 compared with group 1. Transfusion rate was highest in group 2 (P = 0.04 compared with group 1). Prostate weights were also statistically greater in groups 2 (P = 0.003) and 3 (P = 0.02) compared with group 1. Overall, BMI did not increase perioperative and postoperative morbidity. CONCLUSIONS: Robotic laparoscopic radical prostatectomy is safe in overweight and obese patients and might be the surgical management of choice in this subset of patients. Further long-term follow-up with more patients is required to verify this initial observation.

Adult↗

PubMed2006

Solitary ureteral metastases of renal cell carcinoma.

Metachronous presentation of metastatic renal cell carcinoma (RCC) to the ureter is extremely rare. We report a solitary metachronous metastatic RCC in the contralateral ureter 14 months after right radical nephrectomy for Fuhrman grade 2 pT3a clear cell disease after the patient re-presented with gross hematuria. The proximal left ureteral lesion was excised followed by ileal-ureteral interposition. Pathologic examination confirmed metastatic RCC. To date, only 51 cases of metastatic RCC to the ureter have been reported, with only 6 occurring metachronously in the contralateral ureter. Also, we report the presence of focal extramedullary hematopoiesis occurring within this metastatic lesion.

Carcinoma, Renal Cell↗

PubMed2006

Robotic-assisted laparoscopic prostatectomy: first 100 patients with one year of follow-up.

OBJECTIVES: To report our initial experience of 100 patients with robotic-assisted laparoscopic radical prostatectomy. Continued technological advances have expanded our armamentarium of minimally invasive devices and techniques to offer our patients. Robotic-assisted laparoscopic radical prostatectomy has been adopted at many centers. METHODS: This was a nonrandomized prospective study evaluating our initial 100 patients who underwent robotic-assisted laparoscopic radical prostatectomy. The follow-up data were obtained prospectively using the validated Rand 36-item health survey, version 2, and the University of California, Los Angeles, Prostate Cancer Index preoperatively and at 1, 3, 6, and 12 months postoperatively. Patients who required open conversion were excluded from the outcome analysis. Patients who received a sural nerve graft were excluded from the operative analysis. RESULTS: The average age and body mass index of all patients were 58.4 years (range 42 to 70) and 28.5 kg/m2 (range 18.1 to 50.6), respectively, with a median follow-up of 12 months. The average prostate-specific antigen level was 6.07 ng/mL. Seven patients required conversion to an open technique, and four underwent sural nerve grafting. The positive surgical margin rate was 16% (15 of 92). Using the Rand 36-item health survey, version 2, and the University of California, Los Angeles, Prostate Cancer Index health surveys, the average percentage of return to baseline urinary function was 52%, 70%, 79%, and 84% at 1, 3, 6, and 12 months, respectively. The overall average percentage of return to baseline sexual function was 51%, 58%, 66%, and 80% at 1, 3, 6, and 12 months, respectively. CONCLUSIONS: Robotic-assisted laparoscopic radical prostatectomy is a safe and efficient method for achieving prostate cancer control even during the initial learning curve for this procedure.

Adult↗

PubMed2006

Case report: laparoscopic resection of ureteral inverted papilloma.

Inverted papilloma of the ureter is a rare entity, often mistaken for malignancy during work-up. As such, many of these patients have been unnecessarily treated with nephroureterectomy. Herein, we describe a novel laparoscopic approach for the treatment of a ureteral inverted papilloma. To our knowledge, this approach is the first application of laparoscopy for the treatment of this lesion.

Humans↗

PubMed2006

Resident involvement in open radical prostatectomy: a review of urology surgical training.

PURPOSE: The Royal College of Physicians and Surgeons of Canada (RCPSC) and The American Accreditation Council for Graduate Medical Education (ACGME) general objectives mandate that all residents be competent to independently perform select surgical procedures. Unfortunately, no objective standardized measures presently exist for surgical training assessment. Operative logs have been implemented to quantify the number of cases the resident has been exposed to, however, these do not assess their degree of involvement or aptitude. An analysis of what exactly a resident performs, and how well, per case may assist in measuring their training progress. Herein, we evaluate a questionnaire to quantify the level of resident participation in radical retropubic prostatectomy (RRP) and assess whether resident perception of how much involvement in a case correlates with staff surgeons. METHODS AND MATERIALS: Identical, self-administered questionnaires were distributed simultaneously to the resident and staff urologist upon completion of radical prostatectomy. The questionnaire comprised of 14 items, which were completed independently by the resident and the staff urologist. The items assessed which of the 14 specific surgical steps were actually performed by the resident. An analysis was performed to assess the level of agreement. RESULTS: Among all cases performed between June 2002 and July 2003, 64 RRPs performed by two surgeons had completed questionnaires by both resident and staff. Twenty-one (32.8%) cases were performed with a senior resident (R4) and 43 (67.2%) cases were performed with a chief resident (R5). Twenty (31.3%) cases involved pelvic lymph node dissection. Resident performance of key surgical steps, namely dorsal venous ligation, urethral division, lateral pedicle dissection and urethrovesical anastamosis was 59.4%, 62.5%, 84% and 59.4% respectively. Global level of agreement between staff and resident responses was 94.9% (71.4%-100%). CONCLUSION: Our results suggest that there exists good agreement between resident perception of their level of involvement in RRP and staff validation. As such, a residents' assessment of their participation is likely to be accurate. Designation of performance of key operative steps into logs may be more relevant than recording simple exposure to index cases. Attempts at measuring quality of key operative steps in the future may be beneficial.

Canada↗

PubMed2006

Surgical modifications in bladder neck reconstruction and vesicourethral anastomosis during radical retropubic prostatectomy to reduce bladder neck contractures.

PURPOSE: We describe surgical modifications in radical retropubic prostatectomy (RRP) which have significantly reduced the incidence of bladder neck contractures (BNC). MATERIALS AND METHODS: Between March 1994-July 2005, 977 men underwent a RRP by a single surgeon. Group I comprised 548 patients operated upon July 1994-December 1999, without the modifications described below. Group II comprised 429 men operated upon January 2000-December 2004, with the following surgical modifications: 1) reconstruction of the bladder neck (BN) to a diameter of 28 French; 2) placement of the posterior (6 o'clock) vesicourethral suture on mild traction before placing this suture into the bladder, allowing inspection and, if necessary, replacement of any of the previously placed sutures; 3) bladder displacement when tying the vesicourethral sutures which allows the sutures to be tied under direct vision and prevents incorporation of extraneous tissue. Data were retrospectively analyzed. RESULTS: Demographic data were comparable between groups. In group I, 31/548 (5.7%) developed a BNC compared to 1/429 (0.2%) in Group II, p < 0.001. Urinary continence (no pads/maximum of one light pad for security in 24 hours) at 12 months in the 32 patients who developed a BNC was worse when compared to patients who did not develop a BNC (58% versus 80%, p = 0.003). After excluding the patients who developed a BNC, continence rates were comparable between both groups. The positive margin rate at the BN was not adversely affected by these modifications. CONCLUSIONS: Simple, easily applied modifications to the management of the BN and vesicourethral anastomosis can substantially reduce the incidence of BNC.

Adenocarcinoma↗

PubMed2005

Artificial ureters in renal transplantation.

Ureteral strictures in transplanted renal units are initially managed by balloon dilation and indwelling stents. When endourologic management fails, ureteroneocystostomy or pyeloureteral anastomosis to the native ureter is the treatment of choice. Nevertheless, such procedures are not always successful. We present what we believe to be the first two North American cases of silicone-polyester artificial ureters (pyelovesical bypass graft) after failed endourologic or open management of ureteral strictures after renal transplantation. After 12 and 15 months of follow-up, the renal function was stable, with no evidence of obstruction. Long-term follow-up is needed to monitor the rate of late encrustation and obstruction.

Adult↗

PubMed2005

Embolization of a massive retropubic hemorrhage following a tension-free vaginal tape (TVT) procedure: case report and literature review.

INTRODUCTION: Since its description by Ulmsten, the TVT procedure has been proven to be safe and well tolerated. Bleeding and hematoma formation, although rare, can occur. Both conservative and surgical managements of this complication have been described. MATERIALS: We report the first case in which a pelvic branch of the obturator artery was embolized using angiography. RESULTS: Our patient was spared surgical exploration and retained the TVT tape. CONCLUSION: Angiography with vessel embolization, when available, should be considered in the treatment of TVT-procedure retropubic hemorrhages.

Adult↗

PubMed2005

Mucocolpos associated with bladder exstrophy: a case report.

INTRODUCTION: We present the first reported case demonstrating an association of mucocolpos and bladder exstrophy. MATERIALS: A term baby girl presented with bladder exstrophy and underwent a successful primary bladder closure and ureteral reimplantation. Subsequently, she presented with a fluid-filled pelvic mass which was found to be a mucocolpos. RESULTS: Surgical drainage of the collection was required. CONCLUSION: Mucocolpos should be considered in the differential diagnosis of a pelvic mass in a patient with bladder exstrophy.

Bladder Exstrophy↗