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H Baumert

Publications and source records attributed to H Baumert.

At least 19 recordsLinked to original sources
PubMed2006

Laparoscopic versus open simple prostatectomy: a comparative study.

PURPOSE: Laparoscopic simple prostatectomy has recently been developed to remove large prostatic adenomas causing bladder outflow obstruction. To our knowledge the advantages of the laparoscopic vs the standard open approach to this procedure remain undefined. We compared laparoscopic and open simple prostatectomy. MATERIALS AND METHODS: Perioperative data on the first 30 consecutive laparoscopic simple prostatectomies performed by 1 surgeon were collected prospectively and compared with retrospectively collected data on a series of 30 consecutive open simple prostatectomies. A Millin and a transvesical-prostatic technique were used in the laparoscopic group and a transvesical technique was used in the open group. RESULTS: There was no significant difference in prostatic size, patient age or body mass index between the 2 groups. In the laparoscopic group the mean International Prostate Symptom score +/- SD improved from 22.4 +/- 6.9 to 5.7 +/- 3.6 and the urinary flow rate improved from 8.1 +/- 2.5 to 24.6 +/- 12.1 ml per minute (each p <0.001). Mean total blood loss (367 +/- 363 vs 643 +/- 647 ml), irrigation time (0.33 +/- 0.7 vs 4 +/- 3.5 days), duration of catheterization (4 +/- 1.7 vs 6.8 +/- 4.7 days) and hospital stay (5.1 +/- 1.8 vs 8 +/- 4.8 days) were significantly less in the laparoscopic group than in the open group. Mean operative time was longer in the laparoscopic group (115 +/- 30 vs 54 +/- 19 minutes). Of the 30 patients in the laparoscopic group 24 did not require bladder irrigation. There was no apparent difference in the incidence or severity of complications. There was no difference in perioperative parameters or functional results between the 2 different laparoscopic techniques. CONCLUSIONS: Laparoscopic simple prostatectomy has inherent advantages over the open technique. Further studies are indicated to determine whether this technique should be considered the treatment of choice for prostatic adenomas too large for safe endoscopic resection.

Aged↗
PubMed2004

Transperitoneal or extraperitoneal approach for laparoscopic radical prostatectomy: a false debate over a real challenge.

PURPOSE: With our extensive experience of transperitoneal laparoscopic prostatectomy, we evaluated the advantages and disadvantages of the extraperitoneal approach by comparing 2 consecutive series of each procedure. MATERIALS AND METHODS: We reviewed 200 consecutive procedures performed by 2 surgeons. A total of 100 transperitoneal procedures (designated group 1) were compared to the first 100 extraperitoneal cases (designated group 2). RESULTS: Mean operating time was 173 minutes in group 1 and shorter in group 2 at 163 minutes (p = 0.003). Mean blood loss (360 ml in group 1,375 ml in group 2) and transfusion rates (4% in group 1, 3% in group 2) were equivalent. There were no major complications. Minor complications were 10% in group 1 and 9% in group 2. There was no statistical difference in positive margin rate between groups 1 and 2. CONCLUSIONS: The 2 procedures are equivalent in terms of operative, postoperative and pathological data. Each surgeon has to choose considering personal experience, training and standardization.

Adenocarcinoma↗
PubMed2003

Laparoscopic partial nephrectomy for renal tumor: single center experience comparing clamping and no clamping techniques of the renal vasculature.

PURPOSE: We performed a nonrandomized retrospective comparison of 2 techniques for laparoscopic partial nephrectomy, that is without and with clamping the renal vessels. MATERIALS AND METHODS: Between December 1997 and February 2002, 28 consecutive patients underwent transperitoneal laparoscopic partial nephrectomy for renal tumor. In group 1 (12 patients) partial nephrectomy was performed with ultrasonic shears and bipolar cautery without clamping the renal vessels, while in group 2 (16 patients) the renal pedicle was clamped before tumor excision. In group 2 patients intracorporeal kidney cooling was achieved by a ureteral catheter connected to 4C solution. Intracorporeal freehand suturing techniques were used to close the collecting system when opened and approximate the renal parenchyma. RESULTS: All procedures were successfully completed laparoscopically. Mean renal ischemia time +/- SD was 27.3 +/- 7 minutes (range 15 to 47) in group 2 patients. Mean laparoscopic operating time was 179.1 +/- 86 minutes (range 90 to 390) in group 1 compared with 121.5 +/- 37 minutes (range 60 to 210) in group 2 (p = 0.004). Mean intraoperative blood loss was significantly higher in group 1 than in group 2 (708.3 +/- 569 versus 270.3 +/- 281 ml., p = 0.014). Three patients in group 1 and 2 in group 2 required blood transfusions. Immediately postoperatively mean creatinine was 1.26 +/- 0.36 and 1.45 +/- 0.61 mg./dl. in groups 1 and 2, respectively (p = 0.075). Surgical margins were negative in all specimens. Pathological examination revealed renal cell cancer in 18 cases (stages pT1 in 17 and pT3a in 1), oncocytoma in 4, angiomyolipoma in 5 and renal adenoma in 1. CONCLUSIONS: Laparoscopic partial nephrectomy represents a feasible option for patients with small renal masses. Clamping the renal vessels during tumor resection and suturing the kidney mimics the open technique and seems to be associated with less blood loss and shorter laparoscopic operative time.

Aged↗
PubMed2003

Laparoscopic radical prostatectomy: oncological evaluation after 1,000 cases a Montsouris Institute.

PURPOSE: We performed a prospective oncological evaluation of laparoscopic radical prostatectomy in regard to local tumor control and biochemical recurrence. MATERIALS AND METHODS: Between January 1998 and March 2002, 1,000 consecutive patients with a mean age +/- SD of 63 +/- 6.2 years and clinically localized prostate cancer underwent laparoscopic radical prostatectomy at 1 institution. Preoperative 1997 TNM clinical stage was T1a in 6 patients (0.6%), T1b in 3 (0.3%), T1c in 660 (66.5%), T2a in 304 (30.4%) and T2b in 27 (2.7%). Mean preoperative prostate specific antigen (PSA) +/- SD was 10 +/- 6.1 ng./ml. (range 1.5 to 55). Postoperatively, surgical specimens were assessed and positive surgical margins recorded. Factors that could influence the surgical margins status were evaluated. Irrespective of pathological stage or surgical margin status, no adjuvant treatment was proposed before an increasing PSA. PSA recurrence was defined as PSA greater than 0.1 ng./ml. and was confirmed by a second increase. Recurrence time was defined as the time of the first increase in PSA. RESULTS: Postoperative pathological stage was pT2aN0/Nx in 203 patients (20.3%), pT2bN0/Nx in 572 (57.2%), pT3aN0/Nx in 142 (14.2%), pT3bN0/Nx in 77 (7.7%) and pT1-3 N1 in 6 (0.6%). Positive surgical margin rate was 6.9%, 18.6%, 30% and 34% for pathological stages pT2a, pT2b, pT3a and pT3b, respectively (p <0.001). The main predictors of a positive surgical margin were preoperative PSA (p <0.001), clinical stage (p = 0.001), pathological stage (p <0.001) and Gleason score (p = 0.003). The overall actuarial biochemical progression-free survival rate was 90.5% at 3 years. According to the pathological stage, the progression-free survival rate was 91.8% for pT2aN0/Nx, 88% for pT2bN0/Nx, 77% for pT3aN0/Nx, 44% for pT3bN0/Nx and 50% for pT1-3N1 (p <0.001). Of the patients 94% with negative surgical margins and 80% with positive margins had progression-free survival (p <0.001). Preservation of the neurovascular bundles in patients with localized tumors had no significant effect on the subsequent risk of positive surgical margins or progression-free survival. CONCLUSIONS: Based on followup, our evaluation confirms that laparoscopic radical prostatectomy provides satisfactory results in regard to local tumor control and biochemical recurrence.

Actuarial Analysis↗
PubMed2003

Laparoscopic [correction of laproscopic] management of rectal injury during laparoscopic [correction of laproscopic] radical prostatectomy.

PURPOSE: Rectal injury is a potential complication of radical prostatectomy. Because laparoscopic radical prostatectomy is still a challenging procedure, we review the incidence and management of rectal injury in 1,000 cases of consecutive laparoscopic radical prostatectomy performed at our institution. MATERIALS AND METHODS: Of the first 1,000 laparoscopic transperitoneal radical prostatectomies performed between January 1998 and April 2002, 13 (1.3%) were complicated by rectal injury. Mean patient age was 66.5 years (range 58 to 76) and mean prostate specific antigen was 12.9 ng./ml. (range 2.9 to 26). Clinical stage was T1c, T2a and T2b in 5, 7 and 1 patient, respectively. Mean preoperative Gleason score was 5.8 (range 3 to 8). Once recognized the rectal defect was closed laparoscopically in 2 layers and tested for the absence of leakage. Broad-spectrum intravenous antibiotics were given for 7 days. Oral liquids were started the day after surgery with a low residue diet, and a regular diet was started on postoperative day 5. Healing of the vesicourethral anastomosis was confirmed by voiding cystourethrogram on postoperative day 5. RESULTS: All patients underwent a non-nerve sparing procedure except 1 in whom unilateral neurovascular bundle preservation was done. Of 13 injuries 11 were diagnosed and repaired intraoperatively, and 2 were diagnosed postoperatively. Of the 11 cases of intraoperative diagnosis and repair 9 healed primarily without colostomy and peritonitis was diagnosed in the remaining 2 on days 3 and 4, respectively. Of the latter 2 patients 1 required repair of a small rectal defect without colostomy while the other required colostomy. Colostomy was performed in the 2 patients with delayed diagnosis on days 3 and 4 but even then a rectourethral fistula developed in 1, necessitating secondary repair. Average urethral catheterization time was 8.6 days for the 9 patients with an uneventful immediate postoperative course and mean hospital stay was 6.8 days. For the remaining 4 patients urethral catheterization duration was 12, 13, 15 and 120 days, and hospital stay was 7, 16, 21 and 27 days, respectively. There was no perioperative mortality. CONCLUSIONS: Rectal injury during laparoscopic radical prostatectomy requires meticulous intraoperative repair in 2 layers, which allows primary healing without diversion colostomy. For injury prevention scrupulous attention is required during non-nerve sparing radical prostatectomy, particularly at the posterior surface of the prostatic apex.

Aged↗
PubMed2002

Complications of transperitoneal laparoscopic surgery in urology: review of 1,311 procedures at a single center.

PURPOSE: The development of laparoscopic surgery in urology is increasing rapidly. We describe our experience with complications during and after transperitoneal laparoscopic surgery after 9 years of practice. MATERIALS AND METHODS: A total of 1,311 laparoscopic procedures were performed by 5 senior urologists in the same department since 1992, of which 72% were classified as difficult or very difficult (prostatectomy, nephrectomy for cancer, nephroureterectomy, partial nephrectomy, cystectomy, para-aortic lymph node dissection), 27.5% as moderately difficult (nephrectomy for benign disease, adrenalectomy, genitourinary prolapse, ureteropelvic junction, pelvic and ureteral stones, ureterovesical reimplantation, pelvic lymph node dissection) and 0.5% as easy (lymphocele, renal cyst and so forth). RESULTS: There was no mortality or anesthetic complications. The overall transfusion rate was 2.4%. Complications were serious in 0.7% of cases, all of which required reoperation, intermediate in 1.8% of which 1% required reoperation and minor in 1.1%. The main complications were bowel (1.2%), vascular (0.5%) and ureteral injuries (0.8%). The conversion rate was 1.2% and the reoperation rate was 2.4%. Of the patients 1.2% had to be admitted to the intensive care unit. Postoperative complications were observed in 19% of cases. Laparoscopic surgery is associated with essentially the same complications as open surgery, and they, particularly bowel injuries and bleeding, can be diagnosed and often treated with repeat laparoscopy. CONCLUSIONS: Complications during and after transperitoneal laparoscopy remain low and are not superior to those observed during and after open surgery. As laparoscopy becomes more widely used, urologists wishing to learn this technique must realize that the learning process is long but essential.

Adult↗
PubMed2000

Protection of autotransplanted pig kidneys from ischemia-reperfusion injury by polyethylene glycol.

BACKGROUND: Ischemia-reperfusion injury (IRI) is often responsible for graft rejection and leads to delayed graft function of cadaveric kidneys. We have shown that adding polyethylene glycol (PEG 20M) to the preservation solutions helps protect isolated perfused pig kidneys against cold ischemia and reperfusion injury. METHODS: We compared the effects of adding PEG to a simplified high-K+ perfusion solution of cold-stored kidneys to Euro-Collins or University of Wisconsin solutions on the function of reperfused autotransplanted pig kidneys. The left kidney was cold-flushed with the preservation solutions and stored for 48 hr at 4 degrees C before reimplantation. Creatinine clearance and fractional excretion of sodium were analyzed 2 days before surgery and over 7 days after transplantation. Histological sections were obtained 40 min after reperfusion and on day 7 after surgery. RESULTS: Adding PEG to the perfusate significantly reduced IRI from autotransplanted pig kidneys. Creatinine clearance was significantly higher and fractional excretion of sodium was significantly lower in pigs transplanted with kidneys cold-flushed with PEG-supplemented perfusate than in those flushed with Euro-Collins or University of Wisconsin solutions. PEG supplementation also better preserved the integrity of kidney cells and markedly reduced interstitial cell infiltrates. CONCLUSION: PEG protects against IRI and reduces early cellular inflammation. PEG may impair the recruitment and migration of leukocytes into retransplanted pig kidneys. Cold preservation of donor organs with PEG-supplemented solutions may therefore help limit IRI in human renal transplantation.

Animals↗
PubMed2000

Noninvasive monitoring of citrate, acetate, lactate, and renal medullary osmolyte excretion in urine as biomarkers of exposure to ischemic reperfusion injury.

Injury during the transplant process affects the alloantigen-dependent factors and the alloantigen-independent processes of "chronic" rejection. Consequently, the determination of reliable parameters for the assessment of ischemic damage is essential for the prediction of renal changes after ischemia/reperfusion injury. The aim of this study was to assess the ability of (1)H NMR spectroscopy to predict the early graft dysfunction in an ischemia/reperfusion model after preservation in two standard preservation solutions, Euro-Collins (EC) and University of Wisconsin (UW). The second aim was to specify the role of the UW solution in preventing renal medullary injury. Urine and plasma samples from three experimental groups were examined during 2 weeks: control group (n = 5), EC group (cold flushed and 48-h cold storage of kidney in EC and autotransplantation, n = 12), and UW group (cold flushed and 48-h cold storage of kidney in UW and autotransplantation; n = 12). We also examined these kidneys 30-40 min after implantation and on the sacrifice day. Creatinine clearance was significantly reduced in the EC group during the second week. Fractional excretion of sodium and urine N-acetyl-beta-d-glucosaminidase activity were improved but not significantly different in the preserved groups. Urinary concentrations of the alpha-class glutathione S-transferase were significantly greater in the EC group during the first week after transplantation. The most relevant resonances for evaluating renal function after transplantation determined by (1)H NMR spectroscopy were those arising from citrate, dimethylamine (DMA), lactate, and acetate in urine and trimethylamine-N-oxide (TMAO) in urine and plasma. These findings suggest that graft dysfunction is associated with damage to the renal medulla determined by TMAO release in urine and plasma associated with DMA and acetate excretion. Citrate is also a urinary marker that can discriminate kidneys with a favorable evolution. Our results suggest that (1)H NMR spectroscopy is an efficient technique for detecting ischemic damage when accurate and precise data on graft injury is required. In addition, this study outlines the specific impact of the UW solution against injury to the renal medulla.

Acetic Acid↗
PubMed2000

Influence of cold-storage conditions on renal function of autotransplanted large pig kidneys.

BACKGROUND: The consequences of ischemia/reperfusion injury (IRI) on delayed graft function (DGF) and graft survival for kidney recipients remain a matter of debate. Several strategies have been proposed to reduce IRI. We have shown that adding the anti-ischemic drug trimetazidine (TMZ) to different preservation solutions had beneficial effects on the function of reperfused rat and pig kidneys. METHODS: We analyzed the renal parameters of reperfused, autotransplanted large pigs following transplantation. The left kidneys were first removed and cold flushed with Euro-Collins (EC) and University of Wisconsin (UW) solutions (with or without 10-6 mol/L TMZ) and were stored for 48 hours at 4 degrees C. The kidney was then autotransplanted, and the contralateral kidneys were removed. Creatinine clearance, natriuresis, proteinuria, the degree of interstitial fibrosis, the number of CD4, CD8, and macrophage-positive cells, and the amount of vascular cell adhesion molecule-1 were analyzed on kidney biopsies taken at 2, 4 to 5, and 10 to 12 weeks after surgery. RESULTS: The functions of the transplanted kidneys were better preserved after cold flushing with TMZ-supplemented solutions than with TMZ-free solutions. Creatinine clearance was higher, and proteinuria was lower in animals transplanted with kidneys cold flushed with TMZ-supplemented solutions than with TMZ-free solutions. The cytoprotective action of TMZ also reduced interstitial fibrosis and the numbers of infiltrating CD4- and CD8-positive cells. CONCLUSION: These results indicate that the condition of cold preservation may influence long-term kidney graft functions and suggest that, to a certain extent, TMZ reduces the degree of interstitial fibrosis.

Animals↗
PubMed2000

Citrate, acetate and renal medullary osmolyte excretion in urine as predictor of renal changes after cold ischaemia and transplantation.

In organ transplantation, the determination of reliable parameters to assess ischaemic damage is essential to predict renal injury after preservation. The aim of this study was to assess renal medullary injury by 1H NMR (proton nuclear magnetic resonance) spectroscopy after preservation and reperfusion. Three experimental groups of pigs were examined during a 2-week period: control group (n = 4), Euro-Collins group (EC) (cold flushed and 48 h cold storage of kidney in EC and autotransplantation, n = 7), and University of Wisconsin (UW) group (cold flushed and 48 h cold storage of kidney in UW and autotransplantation, n = 7). Creatinine and urea were improved in the two cold stored groups. The most relevant resonances determined by 1H NMR spectroscopy after transplantation were those arising from citrate and acetate in urine and trimethylamine-N-oxide (TMAO) in urine and plasma. We demonstrate that graft dysfunction is associated with damage to the renal medulla as determined by TMAO release in urine and plasma. Conversely, citrate excretion can discriminate kidneys with favourable outcome. This study outlines the specific and beneficial impact of UW solution on renal preservation and suggests that 1H NMR spectroscopy is efficient both to detect ischaemic damage of preserved kidneys and to discriminate the preservation quality between different preservation solutions.

Acetates↗
PubMed2000

Pharmacological limitation of damage to renal medulla after cold storage and transplantation by trimetazidine.

Delayed graft function remains an important complication after renal transplantation. In this study, we investigated the influence of trimetazidine (TMZ), a cytoprotective agent, on renal medullary damage after prolonged preservation and autotransplantation. Pig kidneys were cold-flushed and preserved (48 h at 4 degrees C) with two standard renal preservation solutions Euro-Collins and University of Wisconsin supplemented or not with TMZ (10(-6) M). Analysis of plasma and urine from 48-h-cold-stored and autotransplanted kidneys was performed with biochemical methods and proton NMR spectroscopy. Histological study by light and electron microscopy was performed after reperfusion (30-40 min) and on day 14. The results showed that the preservation in either Euro-Collins or University of Wisconsin solution containing TMZ improved significantly glomerular filtration rate compared with kidneys preserved without TMZ. TMZ significantly reduced renal medullary damage, evidenced by decreased excretion of trimethylamine-N-oxide, dimethylamine, dimethylglycine, and acetate in urine. Proximal tubular injury in TMZ-free groups was assessed by significantly greater Na(+) excretion, amino aciduria, and lactic aciduria than in TMZ-supplemented groups. Urinary concentrating ability was significantly improved in TMZ-preserved groups compared with TMZ-free groups. In TMZ-supplemented groups, there was also a greater excretion of citrate, which is a citric acid cycle metabolite. An extensive reduction in apical brush border of tubular cells, notably those of the proximal tubules, was noted in TMZ-free groups. This study clearly shows that TMZ has a beneficial action on in vivo renal preservation and its major impact is the vulnerable renal medulla.

Animals↗
PubMed2000

[Impact of genital prolapse on the upper urinary tract].

UNLABELLED: The authors reviewed five cases of genital prolapse affecting the upper urinary tract and causing renal failure. CLINICAL CASES: Five patients aged 55 to 75 years presented with genital prolapse, which was known by the patient in 3 cases for a period of 2 to 30 year, but left untreated. All cases had induced bilateral dilatation of the uretero-pyelocaliceal cavities with severe obstructive renal failure in 3 cases, moderate renal failure in 2 cases and associated with hypertension in 2 cases. Repair of prolapse, preceded by upper urinary tract diversion by ureteric and bladder catheters in 3 cases or pessary + bladder catheter because of the patient's age in 2 cases, cured or improved renal failure in 4 patients; only one patient had to be treated by dialysis because of the severity of the residual renal failure severity. DISCUSSION: The frequency (4%) of aetiopathogenic mechanisms (ureteric compression, progressive stretching of the ureter and posterior tilting of the trigone) are analysed. The delayed onset of sudden deterioration and the varying degrees of severity of renal failure demand emergency treatment of stage III prolapse with primary diversion of the upper urinary tract, currently by double J stents, until correction or improvement of renal function, after which surgical repair of the prolapse can be performed according to the usual surgical rules. Intravenous urography is still indicated in this situation. Palliative treatment is only indicated in elderly patients or patients with a high operative risk. The best treatment remains prevention by detection and treatment of prolapse before the development of this fortunately rare complication. CONCLUSION: This short clinical series emphasizes that undiagnosed prolapse can still be complicated by repercussions on the upper urinary tract with a risk of renal failure.

Aged↗
PubMed1999

Renoprotective effects of trimetazidine against ischemia-reperfusion injury and cold storage preservation: a preliminary study.

BACKGROUND: Initial ischemia-reperfusion injury is associated with organ retrieval, storage, and transplantation adversely affects early graft function and influences the development of chronic graft dysfunction. We have recently shown that the protective agent trimetazidine (TMZ) added to preservation solutions: Euro-collins (EC) and University of Wisconsin (UW) was efficient to protect kidneys from ischemia-reperfusion injury in an isolated perfused kidney model. We extended these observations to investigate the role of this drug in the development and progression of organ dysfunction in the autotransplant pig kidney model. METHODS: Five experimental groups were studied. After 48-hr cold preservation, autotransplantation and immediate controlateral nephrectomy was then performed in group EC (EC+placebo (n=8), EC+TMZ (n=8), UW+placebo (n=7), and (UW+TMZ) (n=7) and compared with control group (uninephrectomized, n=4) during 14 days. Blood and urine samples were collected for the measurement of creatinine and blood urea nitrogen on postoperative days 1, 3, 5, 7, 11, and 14. Histological analysis was performed after reperfusion and at day 14. RESULTS: Survivals were 100% in group B and D versus 42% in group A and 57% in group C. Urine production occurred earlier after autotransplantation from TMZ preserved kidneys than in placebo preserved groups. Peak creat and blood urea nitrogen was significantly greater in groups B and D than in groups A and C. TMZ was also efficient both to reduce ischemia-reperfusion injury and to decrease cellular infiltration. CONCLUSION: These results support the beneficial effect of TMZ against ischemia-reperfusion injury and its early effects on grafts in the form of delayed graft function and decreased graft survival. In addition, TMZ reduces inflammatory cellular infiltration in the renal parenchyma.

Adenosine↗
PubMed1998

Lipid peroxidation after cold storage and normothermic reperfusion: the effect of trimetazidine.

Ischemia reperfusion injury is still a leading cause of early graft dysfunction after transplantation. Trimetazidine (TMZ) has been postulated to be protective against renal damage from oxygen free radicals. The aim of this study was to assess the effect TMZ during cold storage (CS) and normothermic reperfusion in an isolated perfused pig kidney model. Three groups were studied: control group, immediately perfused (G0), 48 h CS in Euro-Collins solution (G1), and 48 h CS in Euro-Collins solution plus TMZ (G2). Glomerular filtration rate (GFR) and fractional sodium reabsorption (FRNa+) were calculated during reperfusion from urine and perfusate samples. Lipid peroxidation was determined by the renal tissue level of Schiff bases (SB) and malondialdehyde (MDA) after reperfusion. A histological evaluation was performed after reperfusion. Renal function was significantly improved and lipid peroxidation reduced after preservation in Euro-Collins solution plus TMZ. Functional data were closely related to histological damage. In conclusion, TMZ is a useful protective agent against renal damage induced by CS.

Animals↗