Partial nephrectomy with fibrin glue repair: measurement of vascular and pelvicaliceal hydrodynamic bond integrity in a live and abbatoir porcine model

PURPOSE: Some of the challenges during partial nephrectomy include control of bleeding and repair of the pelvicaliceal system. Fibrin tissue sealants have recently been used to achieve hemostasis and collecting system closure in open and laparoscopic partial nephrectomy. However, there exist little data regarding the intrinsic strength of the bond, especially when applied to the vasculature and the urinary collecting system of the transected kidney. We examined the hydrodynamic bond integrity of a commercially available fibrin tissue sealant in a live porcine animal model undergoing partial nephrectomy. MATERIALS AND METHODS: Open partial nephrectomy was performed in 19 porcine renal units. Collecting system entry was confirmed by methylene blue instillation into the proximal ureter. Fibrin tissue sealant was used to repair 16 renal units, that is 8 kidneys hardened in vivo for 10 minutes and 8 hardened in vivo for 60 minutes. In an additional 3 renal units monopolar electrocautery was used to achieve hemostasis (no fibrin glue used). The strength of vasculature repair was performed by infusing saline into the renal artery (renal vein ligated) and measuring pressure at bond rupture. Similarly the integrity of pelvicaliceal repair was evaluated by retrograde infusion of saline into the collecting system via the proximal ureter and measurement of pressure at bond rupture. RESULTS: Fibrin tissue sealant was successful in achieving prompt hemostasis and it was subjectively superior to cautery alone with regard to bleeding control. Mean renal vascular and pelvicaliceal burst pressure for fibrin sealant treated kidneys was 378 (median 420) and 166 mm Hg (median 170), respectively. There was no significant difference in 10 vs 60-minute hardening times in treated kidneys. In comparison, vascular and pelvicaliceal burst pressure for nontreated (cautery alone) kidneys was 230 (median 220) and 87 mm Hg (median 90), respectively. CONCLUSIONS: Commercially available fibrin tissue sealants can provide supraphysiological renal parenchyma and collecting system sealing pressures after partial nephrectomy. This information supports the potential use of fibrin sealants during open and laparoscopic partial nephrectomy.     

Novel technique for in situ cold perfusion in laparoscopic partial nephrectomy

Background  Following clamping of the renal hilus, warm ischemia is an issue in laparoscopic partial nephrectomy. If ischemia longer than 30 min is anticipated, special protective measures are needed. The aim of this study was to develop a solely laparoscopic technique for in situ cold perfusion of kidneys during laparoscopic partial nephrectomy to increase the tolerance of renal parenchyma to ischemic damage in a porcine model. Methods  Six animals were used in this study. We tried to develop a technique that allowed us to cannulate the renal artery, introduce a catheter to perform an in situ cold perfusion and—the most important feature—secure the catheter throughout the laparoscopic partial nephrectomy. Results  A modified laparoscopic vascular bulldog clamp was ultimately ideal to fulfil expectations. In five pigs, a successful partial nephrectomy in in situ perfusion was performed. The median warm ischemia time, starting from occlusion of the renal artery and vein to the commencement of cold perfusion, was 130 s (range 75–165 s). The subsequent median cold ischemia time in which a partial nephrectomy was simulated was 42 min (range 26–52 min). Conclusions  The newly developed technique expands the armamentarium of the urologist in laparoscopic partial nephrectomy, if the anticipated time of ischemia exceeds 30 min and renal hypothermia is indicated.     

Evaluation of microporous polysaccharide hemospheres for parenchymal hemostasis during laparoscopic partial nephrectomy in the porcine model.

OBJECTIVES: We evaluated the efficacy of Microporous Polysaccharide Hemospheres (MPH) for parenchymal hemostasis during laparoscopic partial nephrectomy (LPN) in the porcine model. METHODS: Six female farm pigs underwent a transperitoneal right lower-pole LPN during occlusion of the renal hilum. Renal parenchyma was excised using cold Endoshears. MPH was applied to the defect and the hilar clamp released. Animals were kept alive for one week. Before sacrifice, left LPN was similarly performed using MPH. Study variables included blood loss, number of MPH applications, hilar clamp time, hemostasis time, perioperative complications, and abnormalities noted at sacrifice. RESULTS: Hemostasis was achieved in all kidneys solely by using MPH. The average excised specimen represented 5.6% (range, 3.6 to 8.5) of renal weight. Mean hilar clamp and hemostatic times were 12.8 minutes (range, 6 to 18) and 2 minutes (range, 1 to 3), respectively. Hemostasis occurred after one MPH application in 8 kidneys (67%). In 3 kidneys, additional MPH powder was required to treat minor residual bleeding. In the remaining kidney, a second standard MPH application was required for hemostasis. No operative complications were encountered. No hematomas or residual MPH was found at necropsy; however, small urinomas were found in 2 of 6 kidneys. CONCLUSIONS: In the experimental porcine model, this initial study suggests that MPH provides effective parenchymal hemostasis during laparoscopic resection of an exophytic kidney lesion.     

Transperitoneal in situ intraarterial cooling in laparoscopic partial nephrectomy

Introduction  

Aiming the principles of open partial nephrectomy, warm ischemia time is the limiting factor especially in case of central or complex tumors in laparoscopy. We demonstrate a novel solely laparoscopic technique for in situ cold perfusion of kidneys with direct catheterization of the renal artery to increase the tolerance of renal parenchyma for ischemia.     

Evaluation of hydrogel tissue sealant in porcine laparoscopic partial-nephrectomy model

BACKGROUND AND PURPOSE: Laparoscopic partial nephrectomy (LPN) is technically challenging with a steep learning curve, primarily because techniques used to control bleeding on the cut surface of the kidney can be ineffective, inconsistent, or challenging. Hemostatic techniques can include intracorporeal suturing, vascular coagulation (argon-beam coagulator, bipolar cautery, laser), and application of various tissue sealants. There is no uniformity of opinion regarding which hemostatic technique is optimal for this application. CoSeal, a hydrogel (Baxter Healthcare Corp, Deerfield, IL), has been effective following vascular surgery but has not been applied to a partial-nephrectomy model. We evaluated the effectiveness of this hydrogel in controlling bleeding and sealing the collecting system by comparing it with intracorporeal suturing and fibrin sealant (Tisseel; Baxter) in a porcine laparoscopic partial-nephrectomy model. MATERIALS AND METHODS: Bilateral synchronous upper-pole partial nephrectomies were performed in two groups of 18 farm pigs, and the three hemostatic techniques (suturing, Tisseel, CoSeal) were applied. In the first group, partial nephrectomies were performed and the pigs sacrificed 3 days postoperatively (acute group). In the second group, the pigs were euthanized 6 weeks postoperatively (chronic group). In both groups, weight, blood pressure, estimated blood loss, weight of the partial and completion nephrectomy specimen, presence/ absence of urinary leak on retrograde study, histopathologic findings, and complications were recorded. RESULTS: The mean weight, blood pressure, estimated blood loss, histopathology findings, and weight of the partial and completion nephrectomy specimens were similar in the three groups. CoSeal did not adhere well to the renal parenchyma compared with Tisseel. All three animals in the acute CoSeal group and three of the six pigs in the sutured group had small urinary leaks during retrograde ureteral study, whereas none of the pigs in the fibrin-glue cohort had urinary leaks. There was one complication (urinary leak) in the CoSeal group, necessitating sacrifice of the animal on postoperative day 8 because of sepsis. CONCLUSIONS: CoSeal is not as effective as fibrin glue in adhering to the cut renal surface and sealing the collecting system during laparoscopic partial nephrectomy.     

New technique with combination of felt, Hem-o-lok and Lapra-Ty for suturing the renal parenchyma in laparoscopic partial nephrectomy

We reported a new technique for closure of the renal parenchyma in laparoscopic partial nephrectomy, shortening the suturing time. Between 2009 and 2011, 41 patients with renal masses 4 cm or smaller in diameter underwent transabdominal laparoscopic partial nephrectomy by a single surgeon in a single institution. The sutures were carried out using 2-0 vicryl CT-1 with a 1.2 × 1.2 cm piece of felt, and both sutures were temporarily held using a Hem-o-lok. After all sutures (median 3) were completed, they were sequentially fixed by sliding the Hem-o-lok, and then locked using the Lapra-Ty. The median times for suturing the renal parenchyma and ischemic time were 13 min and 28 min, respectively. The arrangement of the wound and hemostasis were good. No patients developed urinoma or postoperative bleeding.     

Limitations of laparoscopy for bilateral nephrectomy for autosomal dominant polycystic kidney disease

PURPOSE: We retrospectively studied outcomes following bilateral hand assisted laparoscopic nephrectomy. MATERIALS AND METHODS: We retrospectively reviewed the charts of 18 patients with symptomatic autosomal dominant polycystic kidney disease who underwent bilateral hand assisted laparoscopic nephrectomy. Preoperative radiographic imaging was reviewed retrospectively to determine kidney size based on an ellipsoid shape. A visual analog pain scale with scores of 0 to 10 to assess pain related to autosomal dominant polycystic kidney disease was measured preoperatively and postoperatively. RESULTS: Average patient age was 48.2 years (range 30 to 64). Of the patients 14 successfully underwent bilateral hand assisted laparoscopic nephrectomy, while 4 required open conversion. A total of 16 patients underwent nephrectomy for pain and 2 underwent surgery for frequent recurrent symptomatic urinary tract infections. All patients except 1 underwent renal transplantation before bilateral nephrectomy. There was a significant difference in the volume of the right and left kidneys between the hand assisted laparoscopic and open groups (mean +/- SD 1,043 +/- 672 and 1,058 +/- 603.8 vs 4,052 +/- 548 and 3,592 +/- 1,752 cm(3), p <0.001 and 0.06 respectively). There were 5 complications, including wound infection and protracted ileus in 2 patients each, and incisional hernia in 1. In addition, the difference in mean preoperative and postoperative visual analog pain scores was statistically significant (6.9, range 3 to 10 and 0.5, range 0 to 2, p <0.05). CONCLUSIONS: Bilateral laparoscopic hand assisted nephrectomy is a safe and reliable option in patients requiring removal of the 2 kidneys in a single setting. Rather than performing staged nephrectomies, hand assisted laparoscopic nephrectomy allows the single administration of general anesthesia and provides effective relief of bothersome symptoms in patients with symptomatic autosomal dominant polycystic kidney disease. This procedure is safe in patients with renal transplants. Patients with massive polycystic kidneys with a kidney volume of greater than 3,500 cc are at increased risk for open conversion and they may have improved outcomes if open nephrectomy is attempted from the outset.     

Application of novel hemostatic agent during laparoscopic partial nephrectomy

PURPOSE: We determined if QuikClot, a novel hemostatic agent made of a granulated mineral substance, could be used to control renal parenchymal bleeding and collecting system leakage during open and laparoscopic partial nephrectomy. MATERIALS AND METHODS: After obtaining renal hilar vascular control 2 domestic female pigs underwent bilateral open and 4 underwent unilateral laparoscopic partial nephrectomy. After excision of the lower pole without cautery the hemostatic agent was applied to the cut surface of the kidney and hilar vascular control was released. Additional QuikClot was added until complete hemostasis was achieved. One week postoperatively the animals were sacrificed and the operated kidneys were harvested for ex vivo retrograde pyelograms and histopathological analysis. RESULTS: All partial nephrectomies were performed without complication. Mean operative and warm ischemia times were 62 and 16 minutes, respectively. An average of 23% of renal mass by weight was resected with a mean blood loss of 73 ml per procedure. No cautery, additional hemostatic agents or techniques were used. No animal had clinical or radiographic evidence of urinoma or delayed hemorrhage. Histopathological analysis showed preservation of the renal parenchyma immediately beneath the QuikClot layer. CONCLUSIONS: In the porcine model QuikClot allowed the resection of large renal segments, while providing reliable hemostasis and closure of the renal collecting system. No deleterious effect on underlying renal parenchyma or surrounding tissues was observed.     

Impact of temporary hilar clamping during laparoscopic partial nephrectomy on postoperative renal function: a prospective study

PURPOSE: Laparoscopic partial nephrectomy for small renal tumors has been increasingly performed in the last few years. We prospectively evaluated preoperative and postoperative differential renal function by renal scan in patients with contralaterally functioning kidneys who underwent laparoscopic partial nephrectomy with hilar clamping. MATERIALS AND METHODS: From July 2002 to June 2003, 17 consecutive patients were included in this prospective protocol and underwent laparoscopic partial nephrectomy for exophytic tumors using en bloc hilar clamping. Preoperative renal scan with differential function was performed 1 month before and 3 months after surgery in all patients. technetium labeled diethylenetetraminepentaacetic acid scan was performed in all patients. RESULTS: Mean warm ischemia time was 22.50 +/- 9.78 minutes (range 10 to 44). Preoperative differential renal function and glomerular filtration rate (GFR) in the affected kidneys were 50.20% +/- 4.90% (range 43 to 58) and 75.56 +/- 16.45 ml per minutes (range 39.4 to 105). At postoperative month 3 differential renal function and GFR in the affected kidney were 48.07% +/- 7.16% (range 39% to 63%) and 72.03 +/- 18.17 ml per minutes (range 31 to 101). There was a nonsignificant negative association between hilar clamp time and change in renal function (postoperative - preoperative) of the affected kidney (r = -0.26, p = 0.31), and a positive correlation between clamp time and change in GFR (r = 0.39, p = 0.12) that did not reach statistical significance. CONCLUSIONS: In patients with contralaterally functioning kidney, temporary hilar clamping with a mean warm ischemia time of 22.5 minutes results in preservation of renal function in the affected kidney. Larger studies with longer followup are necessary to study the impact of warm ischemia further.     

Laparoscopic total and partial nephrectomy

Laparoscopic radical nephrectomy has established its role as a standard of care for the management of renal neoplasms. Long term follow-up has demonstrated laparoscopic radical nephrectomy has shorter patient hospitalization and effective cancer control, with no significant difference in survival compared with open radical nephrectomy. For renal masses less than 4cm, partial nephrectomy is indicated for patients with a solitary kidney or who demonstrate impairment of contralateral renal function. The major technical issue for success of laparoscopic partial nephrectomy is bleeding control and several techniques have been developed to achieve better hemostatic control. Development of new laparoscopic techniques for partial nephrectomy can be divided into 2 categories: hilar control and warm ischemia vs. no hilar control. Development of a laparoscopic Satinsky clamp has achieved en bloc control of the renal hilum in order to allow cold knife excision of the mass, with laparoscopic repair of the collecting system, if needed. Combination of laparoscopic partial nephrectomy with ablative techniques has achieved successful excision of renal masses with adequate hemostasis without hilar clamping. Other techniques without hilar control have been investigated and included the use of a microwave tissue coagulator. In conclusion, laparoscopic radical nephrectomy for renal cell carcinoma has clearly demonstrated low morbidity and equivalent cancer control. The rates for local recurrences and metastatic spread are low and actuarial survival high. Furthermore, laparoscopic partial nephrectomy has demonstrated to be technically feasible, with low morbidity. With short term outcomes demonstrating laparoscopic partial nephrectomy as an efficacious procedure, the role of laparoscopic partial nephrectomy should continue to increase.     

Sutureless laparoscopic heminephrectomy using laser tissue soldering

BACKGROUND AND PURPOSE: Widespread application of laparoscopic partial nephrectomy has been limited by the lack of a reliable means of attaining hemostasis. We describe laser tissue welding using human albumin as a solder to control bleeding and seal the collecting system during laparoscopic heminephrectomy in a porcine model. MATERIALS AND METHODS: Laparoscopic left lower-pole heminephrectomy was performed in five female domestic pigs after occluding the hilar vessels. Using an 810-nm pulsed diode laser (20 W), a 50% liquid albumin-indocyanine green solder was welded to the cut edge of the renal parenchyma to seal the collecting system and achieve hemostasis. Two weeks later, an identical procedure was performed on the right kidney, after which, the animals were sacrificed and both kidneys were harvested for ex vivo retrograde pyelograms and histopathologic analysis. RESULTS: All 10 heminephrectomies were performed without complication. The mean operative time was 82 minutes, with an average blood loss of 43.5 mL per procedure. The mean warm ischemia time was 11.7 minutes. For each heminephrectomy, a mean of 4.2 mL of solder was welded to the cut parenchymal surface. In three of the five acute kidneys and all five 2-week kidneys, ex vivo retrograde pyelograms demonstrated no extravasation. In addition, no animal had clinical evidence of urinoma or delayed hemorrhage. Histopathologic analysis showed preservation of the renal parenchyma immediately beneath the solder. DISCUSSION: Laser tissue welding provided reliable hemostasis and closure of the collecting system while protecting the underlying parenchyma from the deleterious effect of the laser during porcine laparoscopic heminephrectomy.     

Laparoscopic partial nephrectomy with a diode laser: porcine results

PURPOSE: To develop a safe and effective technique for laparoscopic partial nephrectomy without need for hilar occlusion. MATERIALS AND METHODS: Laparoscopic transperitoneal lower-pole partial nephrectomy was performed in five 45- to 50-kg female farm pigs using a 980-nm diode laser. Standard transperitoneal access was obtained, and a four-port approach was used to perform a laparoscopic right partial nephrectomy using a diode laser (23 W) without hilar occlusion. The pigs were allowed to recover and 2 weeks later underwent a left laparoscopic partial nephrectomy. Postoperatively, renal function was monitored by serial serum creatinine measurements. Both kidneys and ureters were removed for ex-vivo retrograde pyelograms and histologic analysis. RESULTS: The 980-nm diode laser resulted in successful lower-pole partial nephrectomy without hilar occlusion in all 10 of the kidneys. In three cases, laser hemostasis was insufficient, and adjunctive hemostatic clips were necessary to stop bleeding. The mean operative time was 126 minutes, and the mean laser time was 84 minutes. An average of 23% (range 13%-33%) of the kidney parenchyma was resected. The mean blood loss was 150 mL (range 50-300 mL). There was no evidence of urinary extravasation on ex-vivo retrograde pyelograms at 2 weeks in any of the kidneys. CONCLUSION: Laparoscopic partial nephrectomy without hilar occlusion using the 980-nm diode laser is feasible in the porcine model. Because adjunctive hemostatic measures may be necessary in some cases, clinical trials in humans should be limited to small exophytic tumors.     

原位肾低温灌注腹腔镜下肾部分切除术

目的 探讨一种改进的原位肾低温灌注方法在腹腔镜下肾部分切除术中的临床价值.方法 2009年3-5月,对5例解剖性或功能性孤立肾患者行原位肾低温灌注腹腔镜下肾部分切除术.男3例,女2例;平均年龄49(39～63)岁;肿瘤位于左侧2例,右侧3侧;肿瘤直径平均5.6(3.8～7.0)cm.慢性肾功能不全2例,孤立肾1例,对侧肾萎缩1例,较大良性肿瘤1例.术前经皮穿刺经股动脉介入方法在患侧肾动脉留置带球囊契压导管1根,术中契压导管的球囊注水以阻断患侧肾动脉,并通过契压导管在加压泵下持续向肾动脉内灌注4℃冰盐水约200 ml,以实现患侧肾脏低温原位灌注,同时行腹腔镜下肾部分切除术,术后抽出球囊水以解除肾动脉阻断.结果 5例均成功施行原位肾低温灌注腹腔镜下肾部分切除术,手术时间平均102(80～120)min,肾动脉阻断时间平均35(29～39)min,术中出血量平均190(50～300)ml.低温灌注后皮肤温度平均降低0.6℃,肾脏表面温度降低10.0℃,肿瘤表面温度平均降低9.8℃.术前、术后第1、3、5和10天患者肌酐清除率分别为(64.7±16.9),(48.9±14.5)、(52.1±12.4)、(54.5±13.8)和(54.6±11.7)ml/min,多个相关样本检验显示,各组之间肌酐清除率比较差异有统计学意义(P=0.001).术后第5天和第10天比较差异无统计学意义(P=0.125),其余组间比较差异有统计学意义(P=0.043),术后第5天肌酐清除率基本稳定.结论 原位肾低温灌注腹腔镜下肾部分切除术安全可行,同时解决了腹腔镜下动脉阻断和低温灌注难题,有利于延长肾缺血时间、保护肾功能.     

Laparoscopic partial nephrectomy in cold ischemia: renal artery perfusion

PURPOSE: Laparoscopic partial nephrectomy represents a feasible option for patients with small renal masses. We describe our initial experience with laparoscopic partial nephrectomy in cold ischemia achieved by renal artery perfusion. MATERIALS AND METHODS: From November 2001 to March 2003 laparoscopic partial nephrectomy in cold ischemia was performed in 15 patients with renal cell carcinoma. Cold ischemia was achieved by continuous perfusion of Ringers lactate at 4C through the renal artery, which was clamped. Tumor excision was performed in a bloodless field with biopsy taken from the tumor bed. The collecting system was repaired if needed. Renal reconstruction was performed by suturing over hemostatic bolsters. RESULTS: All procedures were successfully completed laparoscopically by our new technique. Mean operative time was 185 minutes (range 135 to 220). Mean ischemia time was 40 minutes (range 27 to 101). Estimated mean intraoperative blood loss was 160 ml (range 30 to 650). Entry to the collecting system in 6 patients was repaired intraoperatively. Additional vascular repair was done in 2 patients. There were no significant postoperative complications. Postoperative followup in 8 patients showed that the renal parenchyma was not damaged by the ischemic period. CONCLUSIONS: Our initial experience of incorporating cold ischemia via arterial perfusion into laparoscopic partial nephrectomy shows the feasibility and safety of the technique. We believe that this approach has the potential to make laparoscopic partial nephrectomy for renal cell carcinoma safe and reliable.     

Balloon occlusion and hypothermic perfusion of the renal artery in laparoscopic partial nephectomy

Objectives: We describe our initial experience with renal arterial catheterization for temporary balloon occlusion of renal artery and hypothermic perfusion during laparoscopic partial nephectomy and compare the preoperative and postoperative nephron function. Methods: Fifteen patients received laparoscopic partial nephrectomy from September 2005 to December 2006. During the operations, the balloons of the arterial catheters were filled with distilled water to achieve pedicle control. Chilled Ringers lactate was continuously infused into the catheters for renal hypothermia. Postoperative Tc‐99m diethylenetriamine pentaacetic acid (DTPA) renal scintigraphies were carried out to estimate differential renal function. The volumes of the renal tumors, tumor‐bearing and contralateral kidneys from CT scans were measured using commercial software. Estimated creatinine clearance was calculated with Cockroft Gault formula. Results: All procedures were successfully completed. Mean tumor size was 18.4 mL (range 2.14 to 59.0). Estimated mean intraoperative blood loss was 287 mL (range minimal to 1200). Mean estimated creatinine clearance per unit volume of functional renal parenchyma did not change statistically after the operation. Multiple regression analysis revealed that ischemic time was a significant variable which correlated with the value of lost total estimated creatinine clearance of the tumor bearing kidney. Conclusions: The initial experience shows that renal arterial catheterization for temporary balloon occlusion and hypothermic perfusion of the renal artery in laparoscopic partial nephectomy is safe, feasible and effective. The postoperative kidney function measured by mean estimated creatinine clearance per unit of functional renal volume was similar to the preoperative measurement.     

Outcome and complications of laparoscopic nephrectomy in patients with previous renal surgery

OBJECTIVE: The aim of this study was to evaluate the technical difficulties, limitations, outcome, and complications of laparoscopic nephrectomy in patients with previous ipsilateral renal surgery. MATERIALS AND METHODS: Eighteen patients with a history of epsilateral renal surgery underwent laparoscopic simple nephrectomy for benign renal disease at our center between November 2001 and March 2005. All patients were informed about the details of the laparoscopic procedure, and an informed consent was obtained that included the possibility of an emergency laparotomy. All procedures performed were carried out through a transperitoneal approach. A separate table with a laparotomy set was available in the room and ready for open conversion. RESULTS: The procedure was completed in 13 patients. Excluding the cases converted to open surgery, the operative time ranged from 120 to 210 minutes, with a mean of 170 +/- 32.9. The intraoperative blood loss ranged from 30 to 400 cc, with a mean blood loss of 100. Complications included minor visceral injury (liver) in 1 patient, minor bleeding in 2, major bleeding (open conversion) in 1, technical failure (open conversion) in 4, postoperative bleeding (reexploration) in 1, and postoperative renal bed collection in 1. CONCLUSIONS: Laparoscopic nephrectomy is an alternative to the open nephrectomy for the removal of nonfunctioning kidneys in benign diseases and results in less morbidity and a shorter hospital stay. A higher conversion to open and complication rate should be expected in patients with previous open or endoscopic renal surgery and postinflammatory conditions.     

Efficacy of ultrasonic tissue dissector and tissue glue for laparoscopic partial nephrectomy in a porcine model

The purpose of this study was to evaluate the efficacy and long-term tissue effects of ultrasonic dissector and cyanoacrylate glue during laparoscopic partial nephrectomy in a porcine model. Nine domestic pigs underwent laparoscopic left lower pole partial nephrectomy without vascular control. An ultrasonic tissue dissector was used to assist in the parenchymal incision, and the raw surfaces of the kidneys, including the exposed urinary system, were sealed with cyanoacrylate glue. No internal stents or additional sutures were placed. Intraoperative hemorrhages and urinary extravasation were recorded. The animals were humanely killed 28 days after undergoing the operations. The long-term effects of ultrasonic dissector and cyanoacrylate glue on the healing process of urothelium and renal parenchyma were determined histologically. All pigs survived the laparoscopic partial nephrectomy, and the blood loss ranged from 0 to 120 ml (mean, 60 ml). The average operative time was 89 +/- 10 min. The severity of the bleeding was minimal in six animals and moderate in three animals. No urinary extravasation was found using intravenous urography at the 28th postoperative day. No urinary fistula or renal abscess formation was found histologically. Cyanoacrylate glue infiltrated into the tissue defects and did not dissolve. The glue was encased by fibrotic tissue with minimal foreign body inflammatory reaction. Ultrasonic dissector was effective in achieving hemostasis during laparoscopic partial nephrectomy without the need of vascular control in pigs. Cyanoacrylate glue achieved good long-term adhesive power. The sealing effects provided by cyanoacrylate glue were adequate to prevent urinary extravasation from urothelial defects at least for 1 month.     

Comparison of laparoscopy-assisted partial nephrectomy using digital compression versus purely laparoscopic nephrectomy using vascular pedicle clamp in a porcine model

BACKGROUND AND PURPOSE: Laparoscopic partial nephrectomy raises a number of technical issues, particularly in the control of bleeding. We compared digital compression during hand assistance with a vascular clamp. MATERIALS AND METHODS: Laparoscopic transperitoneal bilateral lower-pole partial nephrectomy was performed on six pigs, with a vascular clamp being used on one side and digital pressure through an Omniport or Lapdisk on the other. The pigs were then euthanized and the kidneys harvested for histologic examination. RESULTS: Good hemostasis was obtained regardless of the technique. However, the estimated blood loss was significantly greater with digital compression (96.7 versus 9.6 mL). There were no significant micropathological differences in the kidneys. The surgeons rated suture tying and placement much easier with the purely laparoscopic technique. CONCLUSIONS: Both techniques are feasible. In experienced hands, the purely laparoscopic technique takes no longer than the hand-assisted technique and is associated with less blood loss, easier suturing, and better cosmesis. However, long-term follow-up is needed before clinical use can be contemplated.     

Water jet assisted laparoscopic partial nephrectomy without hilar clamping in the calf model

PURPOSE: Hemostasis represents a primary challenge during laparoscopic partial nephrectomy (LPN). We typically clamp the renal artery/vein en bloc and perform LPN expeditiously under warm ischemia conditions. We evaluated Helix Hydro-jet assisted LPN without renal hilar vascular control in the survival calf model. MATERIALS AND METHODS: Staged bilateral LPN using the Hydro-jet was performed without renal hilar vessel control in 10 survival calves (20 kidneys). Parenchymal hydrodissection was performed with a high velocity, ultracoherent saline stream at 450 psi through a small nozzle with integrated suction at the tip. The denuded intrarenal parenchymal blood vessels were precisely coagulated with a BIClamp bipolar instrument and transected. Followup involved biochemical, radiological and histopathological evaluation at designated sacrifice intervals of 1 and 2 weeks, and 1, 2 and 3 months, respectively. RESULTS: All LPNs were completed successfully without open conversion. Of 20 LPNs 18 (90%) were performed without hilar clamping. Pelvicaliceal suture repair was necessary in 5 of 10 chronic kidneys (50%). Mean Hydro-jet(R) partial nephrectomy time was 63 minutes (range 13 to 150), mean estimated blood loss was 174 cc (range 20 to 750) and mean volume of normal saline used for hydro-dissection was 260 cc (mean 50 to 1,250). No animal had a urinary leak. Histological sections from the acute specimen revealed a thin (1 mm) layer of adherent coagulum at the amputation site with minimal thermal artifact. At 2 weeks a layer of adherent fibro-inflammatory pseudomembrane with giant cell reaction was seen. CONCLUSIONS: In this more stringent and robust survival calf model Hydro-jet assisted LPN can be performed without hilar vessel control, thus, completely avoiding warm ischemia. This approach has the potential to decrease the level of technical difficulty inherent in LPN.     

Hemostatic techniques during laparoscopic partial nephrectomy

PURPOSE OF REVIEW: To review the current techniques and technologies being used for hemostatic control during laparoscopic partial nephrectomy. RECENT FINDINGS: Laparoscopic nephron-sparing surgery has become more common for the treatment of renal masses. With increasing experience, the indications for nephron sparing are increasing. Despite the increased use of these techniques in high-volume centers, however, more widespread application has been limited because of the need for advanced laparoscopic skills including the laparoscopic control of intraoperative renal bleeding. As a result, many techniques have been developed to achieve hemostasis, including conventional suture repair, tissue sealants, radiofrequency ablation, lasers, water dissection, and microwave tissue coagulation. SUMMARY: Laparoscopic partial nephrectomy is a technically challenging procedure. Many promising techniques are being developed currently, most geared toward improved hemostasis and collecting system repair. These techniques and products have made, and will continue to make, the procedure less demanding and more universally accepted.