Jose Benito A. Abraham

Robotic versus standard laparoscopic partial/wedge nephrectomy: a comparison of intraoperative and perioperative results from a single institution.

PURPOSE Laparoscopic partial/wedge nephrectomy, similar to laparoscopic radical prostatectomy, is a technically challenging procedure that is performed by a limited number of expert laparoscopic surgeons. The incorporation of a robotic surgical interface has dramatically increased the use of minimally invasive pelvic surgery such that robotic laparoscopic radical prostatectomy is commonly performed even by laparoscopically naïve surgeons. This analysis compares the outcomes of our initial experience with robot-assisted laparoscopic partial nephrectomy (RLPN) performed by an experienced open surgeon to that of standard laparoscopic partial nephrectomy (LPN) performed by two experienced laparoscopic surgeons. PATIENTS AND METHODS We reviewed the medical records of 11 consecutive patients who underwent 12 standard LPNs (EMM, RVC) (one patient had two unilateral tumors) and 10 consecutive patients (representing the first 11 of such robotic procedures performed at our institution) who underwent 11 RLPNs (one patient had bilateral tumors managed in an asynchronous manner) (DKO). RESULTS The mean tumor size was 2.3 cm (range 1.7-6.2 cm) for LPN and 3.1 cm (range 2.5-4 cm) for RLPN. The mean total procedure time was 289.5 minutes (range 145-369 min) for LPN and 228.7 minutes (range 98-375 min) for RLPN (P=0.102). The mean estimated blood loss was 198 mL (range 75-500 mL) for LPN v 115 mL (25-300 mL) for RLPN (P=0.169). The mean warm ischemia time was 35.3 minutes (range 15-49 min) in the LPN group and 32.1 minutes (range 30-45 minutes) in the RLPN group (P=0.501). CONCLUSIONS Introducing a robotic interface for laparoscopic partial/wedge resection allowed a fellowship-trained urologic oncologist with limited reconstructive laparoscopic experience to achieve results comparable to those for laparoscopic partial/wedge resection performed by experienced laparoscopic surgeons. In this regard, the learning curve appears truncated, similar to that with robot-assisted laparoscopic prostatectomy.

Rapid Communication: Robot-Assisted NOTES Nephrectomy: Initial Report

BACKGROUND AND PURPOSE Natural Orifice Transluminal Endoscopic Surgery (NOTES) using the daVinci robot (Intuitive Surgical, Sunnyvale, CA) has never been applied to urologic surgery. Here we present our initial experience with a combined transvaginal and transcolonic, single-port, robot-assisted NOTES nephrectomy. METHODS An acute experiment was performed in a female farm pig. A single 12-mm trocar was placed in the midline, and two 12-mm standard laparoscopic ports were placed into the abdomen via the vagina and the colon. The robotic ports were then telescoped into the 12-mm ports, and the daVinci S robot was docked. Dissection was performed using the Hot Shears and the ProGrasp instruments. The robotic camera was placed via the midline port and held by an assistant. Using the 12-mm transvaginal port, the renal artery and vein were divided separately with a vascular Endo GIA (US Surgical, Norwalk, CT) stapler. The kidney was placed into a 10-mm entrapment sack and removed intact via the vagina. RESULTS Total operative time was 150 minutes. Estimated blood loss was less than 50 mL. No intraoperative complications occurred. CONCLUSION A robot-assisted NOTES nephrectomy was accomplished in a porcine model using the daVinci S robot. Additional testing on survival animals is necessary to further explore this approach.

Comparative Analysis of Laparoscopic and Robot-Assisted Radical Cystectomy with Ileal Conduit Urinary Diversion

PURPOSE To compare our experience with laparoscopic radical cystectomy (LACIC) and robot-assisted laparoscopic radical cystectomy (RACIC) with ileal conduit urinary diversion. PATIENTS AND METHODS Prospective data were gathered on 20 consecutive patients undergoing LACIC performed between August 2002 and July 2005, and on 14 consecutive patients undergoing RACIC performed between March 2005 and December 2006. Radical cystectomy with pelvic lymphadenectomy was performed laparoscopically or robotically, and an ileal conduit urinary diversion was performed extracorporeally. RESULTS There was no significant difference in terms of preoperative factors or baseline tumor characteristics and no significant difference in mean operative time (410 min v 419 min) between groups. There was less blood loss (212 mL v 653 mL; P < 0.0001) and fewer transfusions (42.8% v 70%; P < 0.0011) in the RACIC group. There was one intraoperative complication (7%) and no conversions in the RACIC group. There were three (15%) intraoperative complications all leading to conversion in patients undergoing LACIC. Three (21%) patients in the RACIC group and 10 (50%) patients in the LACIC group had at least 1 post-operative complication. The mean number of days to oral intake was less in the RACIC group (2.3 v 6.1; P = 0.012). There was no significant difference in the number of lymph nodes excised (P = 0.09) between groups. Bilateral extended lymphadenectomy was performed in 10 (71%) RACIC patients with a mean of 22.3 lymph nodes harvested and in 16 (80%) LACIC patients with a mean of 16.5 lymph nodes harvested. There were no positive margins in patients in the LACIC group and one (7.1%) among patients in the RACIC group--a patient with pT4 disease. CONCLUSION Both laparoscopic and robot-assisted radical cystectomies can be performed safely without compromising oncologic standards for surgical margins and extent of lymphadenectomy. In this early experience, the robot-assisted approach appears to have a shorter learning curve, and it is associated with less blood loss, fewer postoperative complications, and earlier return of bowel function than LACIC.

Comparative Study of In Vivo Lymphatic Sealing Capability of the Porcine Thoracic Duct Using Laparoscopic Dissection Devices

PURPOSE Sealing the lymphatic vessels during abdominal and pelvic surgery is important to prevent the leakage of lymphatic fluid and its resultant sequelae. To our knowledge we compared for the first time the quality of lymphatic sealing by each of 4 commonly used laparoscopic dissection devices. MATERIALS AND METHODS A total of 12 domestic pigs were used to test dissecting devices, including monopolar scissors (Ethicon Endo-Surgery, Cincinnati, Ohio), Harmonic ACE Scalpel, LigaSure V, EnSeal and Trissector. A midline incision was made from mid sternum to umbilicus, the diaphragm was divided and the porcine thoracic duct was isolated. In all animals each device was used to seal an area of the duct and each seal was placed at least 2 cm from the prior seal. In group 1 the thoracic duct of 6 pigs was cannulated with a 5Fr catheter and the seal was subjected to burst pressure testing using a burst pressure measuring device (Cole-Parmer, Vernon Hills, Illinois). In the 6 pigs in group 2 each seal was immediately sent for histopathological evaluation. Specimens were given a score for the extent of cautery damage, including 0-none, 1-minimal, 2-moderate, 3-severe and 4-extreme. RESULTS A total of 64 seals were created, of which 35 were subjected to burst pressure testing. Mean size of the thoracic duct was 2.6 mm. No acute seal failures were observed with any bipolar device or the harmonic shears. However, 2 immediate failures (33%) were seen with monopolar scissors. Mean burst pressure for monopolar scissors, Harmonic ACE Scalpel, LigaSure V, EnSeal and Trissector was 46 (range 0 to 165), 540 (range 175 to 795), 258 (range 75 to 435), 453 (range 255 to 825) and 379 mm Hg (range 175 to 605), respectively (p <0.05). Trissector, Harmonic ACE Scalpel and EnSeal generated seals with significantly higher burst pressure than that of monopolar scissors (p <0.05). Histopathological evaluation revealed that LigaSure caused less thermal damage than Trissector and EnSeal (p <0.05). CONCLUSIONS Each device tested except monopolar scissors consistently produced a supraphysiological seal and should be suitable for sealing lymphatic vessels during laparoscopic surgery.

In Vitro Evaluation of Nitinol Urological Retrieval Coil and Ureteral Occlusion Device: Retropulsion and Holmium Laser Fragmentation Efficiency

PURPOSE Retropulsion of ureteral stones during laser lithotripsy may result in difficult and incomplete stone fragmentation. The Stone Cone nitinol urological retrieval coil and the NTrap nitinol ureteral occlusion device have been introduced into clinical practice to possibly limit stone retropulsion and enhance the efficiency of holmium laser (Convergent Laser Technologies, Alameda, California) stone fragmentation. MATERIALS AND METHODS A total of 360 BegoStone Plus phantom stones (Bego USA, Smithfield, Rhode Island) of similar mass and weight were divided into 3 groups, including control, Stone Cone and NTrap. The groups were further subdivided according to fiber size (200 or 400 microm) and pulse width (350 or 700 microsec). These stones were placed in a horizontal pipette 12 mm in diameter, submerged in normal saline and disintegrated at laser settings of 1 J and 10 Hz continuously applied for 300 seconds. Retropulsion in cm and fragmentation efficiency with mass loss in mg were measured after treatment. RESULTS The 2 devices were effective for preventing retropulsion. In the control group the mean +/- SD retropulsion distance using a 350-microsec pulse width with the 200 and 400 microm fibers was 18.4 +/- 5.9 and 14.1 +/- 4.6 cm, while it was 6.2 +/- 2.6 and 5.6 +/- 2.4, respectively, using the 700-microsec pulse width. There was a statistically significant higher loss of stone weight in the Stone Cone and NTrap experimental groups than in the control group (p <0.0001). However, there was no difference between the 2 experimental groups across all groups (p = 0.32). CONCLUSIONS The Stone Cone and NTrap eliminated retropulsion and equally improved fragmentation efficiency. The maximum efficiency of fragmentation was seen using the 200 microm fiber at a 700-microsec pulse width.

Third Prize: Flank Position Is Associated with Higher Skin-to-Surface Interface Pressures in Men Versus Women: Implications for Laparoscopic Renal Surgery and the Risk of Rhabdomyolysis

BACKGROUND AND PURPOSE There have been several reports of rhabdomyolysis occurring after prolonged laparoscopic procedures in the flank position. Accordingly, we evaluated interface pressures between the skin and three commonly used operating room table surfaces. The aim of our study was to determine if pressure changes could be related to body mass index (BMI), sex, position, and/or the table surface material. PATIENTS AND METHODS Ten men and 10 women were grouped according to BMI <25 or >or=25, with five participants in each group. Subjects were placed in the left lateral decubitus position with the operating table flat, half flexed, fully flexed, half flexed with the kidney rest elevated, and fully flexed with the kidney rest elevated. Interface pressures were recorded, using an X-Sensor pressure sensing mat, for 5-minute periods in each of the described positions on each surface. RESULTS Sex and BMI were statistically significant predictors of increased pressures (P= 0.0042 and 0.0402, respectively). The parameter estimate for the difference between men and women was 4.63 mm Hg (P= 0.0002), and the difference for BMI >or= 25 compared with <25 was also significant (P < 0.0209). Full table flexion (50-degree) produced significantly higher pressures than both flat (P= 0.0001) and the half-flexed (25-degree) position (P < 0.0001). Positions with the kidney rest elevated were associated with significantly higher pressures than without elevation (P < 0.0001). With regard to the surface used, egg crate provided lower pressures than gel pads (P= 0.0117). CONCLUSION Women have significantly lower interface pressures when compared with men. BMI >or= 25 also increases interface pressures. The use of the kidney rest is associated with markedly increased pressure; use of a half-flexed position is preferable to a full-flexed position. These data have implications for patient positioning and identification of persons at risk for rhabdomyolysis during laparoscopic renal surgery.

Laboratory Evaluation of Laparoscopic Vascular Clamps Using a Load-Cell Device—Are All Clamps the Same?

PURPOSE The use of effective vascular clamps is key to successful laparoscopic partial nephrectomy. Based on our clinical experience the occlusive capabilities of vascular clamps appeared to be quite variable. We compared the occlusive force of currently available laparoscopic vascular clamps. MATERIALS AND METHODS The jaw force of 3 laparoscopic vascular clamps (Aesculap(R), Klein Surgical Systems, San Antonio, Texas and Karl Storztrade mark) were measured by clamping a 2.2 mm compression load cell (Interface Advanced Force Measurement, Scottsdale, Arizona) in pound-force. The variables tested were handheld Satinsky, DeBakey and Storz clamps vs bulldog clamps, proximal, middle and distal application position, new vs used bulldog clamps and new vs used Satinsky handheld clamps. In addition, handheld clamps were tested according to the force generated by the notches in the locking mechanism. Force retention was also determined for all instruments after clamping a 20Fr latex rubber catheter for an hour. Finally, leak pressure studies were performed using a harvested porcine artery to determine the relationship between jaw force and leak pressure in mm Hg of bulldog and Satinsky handheld clamps using a pressure gauge (Cole-Parmer(R)). RESULTS Handheld vascular clamps provided greater force than bulldog clamps. The proximal position closest to the hinge provided the greatest force across all instruments. Compared to new clamps the 2-year-old Klein Surgical Systems bulldog clamps showed a greater than 40% decrease in jaw force at all positions, whereas the 3-year-old Aesculap bulldog clamps decreased in jaw force by less than 9% at all positions. The 2-year-old Satinsky handheld clamps showed a decrease of 20%, 9% and 0% at the distal, middle and proximal jaw positions, respectively. Also, there was a positive correlation between force and the number of notches applied in handheld clamps. In addition, all instruments maintained jaw force after 1 hour of continuous clamping. Finally, leak pressure studies performed with used clamps showed that Klein Surgical Systems bulldog, Aesculap bulldog and Satinsky handheld clamps leaked at a pressure of 153 to 223, 465 to 795 and 1,500 to 2,600 mm Hg, respectively. CONCLUSIONS Vascular clamps have varying occlusive forces according to clamp type, manufacturer, jaw and teeth characteristics, jaw clamping position and duration of use. However, across all clamps the jaw force was greatest at the proximal position. This is most important when applying laparoscopic bulldog clamps. In contrast, all handheld vascular clamps generated higher force than intracorporeal bulldog clamps. At 1 notch the handheld vascular clamps provided supraphysiological occlusion force regardless of position or manufacturer.

The UCI Seldinger technique for percutaneous renal cryoablation: protecting the tract and achieving hemostasis.

PURPOSE To describe our Seldinger technique of percutaneous renal cryoablation that was devised to facilitate renal biopsy, cryoprobe placement, and instillation of adjunctive hemostatics while protecting surrounding tissues from cryoinjury. PATIENTS AND METHODS This approach was used to manage 13 renal masses in 12 adult patients. Under CT-fluoroscopic guidance, an access needle was inserted to abut the surface of the tumor, followed by an Amplatz super-stiff guidewire and a customized coaxial catheter system, which was used as a conduit for needle biopsy, cryoprobe insertion, and FloSeal instillation. In addition, a porcine model was used to compare the temperature readings adjacent to the sheathed and the unsheathed cryoprobe during percutaneous renal cryoablation. RESULTS In all patients, the use of this access approach was accomplished without incident. Two patients needed blood transfusions. No patient had significant skin, muscle, or nerve debility. At a mean follow-up of 11 months, none had evidence of persistent disease on CT or MRI contrast imaging. In the porcine model, the customized sheath protected the surrounding tissues from reaching temperatures below 5 degrees C while temperatures down to -15 degrees C were obtained when no insulating sheath was used. CONCLUSIONS A modified Seldinger technique enabled us to perform percutaneous renal cryotherapy through a single access channel, which facilitated access for biopsy, cryoprobe placement, and instillation of hemostatic agents. This approach may provide a protective barrier against cryogenic damage to neighboring tissues and could theoretically help minimize the chance of tract seeding.

LapED® 4-In-1 Silicone Training Aid for Practicing Laparoscopic Skills and Tasks: A Preliminary Evaluation

OBJECTIVE We developed a simple, inexpensive model to simulate four reconstructive laparoscopic procedures: pyeloplasty, vesicourethral anastomosis, bladder injury repair, and partial nephrectomy. MATERIALS AND METHODS Liquid silicone was applied in layers to a mold to create the 4-in-1 model. A questionnaire evaluating its face and content validity was distributed to postgraduate urologists participating in a mini-residency program at the University of California-Irvine (UCI), and in the 2006 American Urological Association Hands-On course on reconstructive laparoscopic pyeloplasty. RESULTS A total of 56 postgraduate urologists used the model and completed an evaluation questionnaire. Ninety-four percent (51/54) and 96% (48/50) agreed that the model was helpful for practicing laparoscopic pyeloplasty and urethrovesical anastomosis, respectively. Urologists who were experienced in either performing laparoscopic pyeloplasty (n = 6) or robot-assisted and/or laparoscopic prostatectomy (n = 11) would recommend this model to surgeons in training. Overall, 94% (48/51) and 96% (50/52) of the respondents would recommend this model for postgraduate surgeons and residents, respectively. CONCLUSION We present a versatile model for practicing laparoscopic and robotic suturing and knot-tying skills in four reconstructive urologic procedures. Our results support the face and content validity of this model for performing pyeloplasty and vesicourethral anastomoses.

Laparoscopic partial nephrectomy: six degrees of haemostasis.

Study Type – Therapy (case series) 
Level of Evidence 4