- Email: [email protected]
Minimizing knot tying during reconstructive laparoscopic urology
ADULT UROLOGY
MINIMIZING KNOT TYING DURING RECONSTRUCTIVE LAPAROSCOPIC UROLOGY ARIEH L. SHALHAV, MARCELO A. ORVIETO, GARY W. CHIEN, ALBERT A. MIKHAIL, GREGORY P. ZAGAJA, AND KEVIN C. ZORN
ABSTRACT 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. UROLOGY 68: 508–513, 2006. © 2006 Elsevier Inc.
L
aparoscopic radical nephrectomy has rapidly evolved into the standard of care for patients with localized renal tumors1 since its introduction in 1991.2 However, reconstructive laparoscopic surgery in which substantial knot tying is necessary, such as laparoscopic partial nephrectomy (LPN), laparoscopic radical prostatectomy (LRP), and laparoscopic pyeloplasty (LP), has had slower adoption rates in the urologic community. This has largely been because of the high level of difficulty related to these procedures. In this study, we present a modification to simplify these procedures using the Lapra-Ty clip (LTc; Ethicon EndosurFrom the Section of Urology, University of Chicago Pritzker School of Medicine, Chicago, Illinois Reprint requests: Kevin C. Zorn, M.D., Section of Urology, Department of Surgery, University of Chicago Pritzker School of Medicine, 5841 South Maryland Avenue, MC6038 J-653, Chicago, IL 60637. E-mail: [email protected] Submitted: December 20, 2005, accepted (with revisions): March 29, 2006 © 2006 ELSEVIER INC. 508
ALL RIGHTS RESERVED
gery, Piscataway, NJ) during knot tying. The LTc is designed to substitute for a knot,3 thereby minimizing intracorporeal knot tying. It also reduces the “cheese slicing” effect of the suture when cinching a knot, such as can occur during conventional knot tying. In contrast to knot tying, the LTc also permits the surgeon to apply additional tension if needed. The clip is composed of absorbable polydioxanone and can be applied to a single strand of 1-0, 2-0, 3-0, or 4-0 suture. The clip maintains tensile strength for 14 days and is completely absorbed by 90 days.4 We assessed the feasibility and specific complication rates related to the use of the LTc in all LPN, robotic LRP (RLRP), and LP procedures performed at our institution. MATERIAL AND METHODS All data were retrospectively reviewed with the approval of the institutional review board. From October 2002 to July 2005, 75 patients underwent LPN for clinical Stage T1a (n ⫽ 67), T1b (n ⫽ 7), or T2 (n ⫽ 1) renal tumors. A single surgeon (A.L.S.) per0090-4295/06/$32.00 doi:10.1016/j.urology.2006.03.071
formed all LPN and LP procedures. A total of 300 patients underwent RLRP from February 2003 to July 2005. Two surgeons (A.L.S. and G.P.Z.) performed all procedures. Finally, 14 patients underwent LP from November 2003 to July 2005; all procedures were performed by one surgeon (A.L.S.).
defect remained in the renal pelvis, it was closed using additional suture. Similar postoperative drain management as that for the LPN group was used for the LP group. Perioperative complications related to the collecting system closure, such as urinary leakage and bleeding, were assessed.
TECHNIQUE FOR MINIMIZING KNOT TYING DURING LPN Our technique for eliminating knot tying during LPN has been previously described.5 In brief, 6-in. 2-0 Vicryl sutures (coated polyglactin 910) on CT-1 needles and 6-in. 3-0 Vicryl sutures on SH needles with an LTc at the tail end of each suture were used. After tumor excision and argon beam coagulation, the 3-0 sutures were used to close the collecting system and open-ended vessels. If any suspicion regarding margin status was present, deep tumor bed biopsies were sent for frozen section analysis. Once a figure-of-eight or running suture was completed, the needle end of the suture was cinched to the desired tension and a second LTc was placed on the suture at the level of the tissue. The renal parenchymal defect was then repaired using 2-0 Vicryl sutures starting at the capsular surface. Once the desired tissue compression was achieved, a second LTc was cinched down to the level of the tissue. Sometimes, additional tension might be needed on the suture to ensure hemostatic compression. Another LTc can be applied more proximally to provide additional tension. FloSeal (Fusion Medical Technologies, Mountain View, Calif) was then applied to the exposed defect. Excess tension should be avoided, especially with the additional tension that will be created by unclamping the renal artery. This auto-tension is created by the increased tissue turgor related to the return of blood flow. Standard postoperative drain management included routine removal of the Foley catheter the morning after surgery, with the Jackson-Pratt drain removed later that same afternoon if no increased output was noted. The warm ischemia time (WIT) and postoperative complications related to the use of the LTc, such as urinary leak and bleeding, were assessed.
TECHNIQUE TO MINIMIZE KNOT TYING DURING VESICOURETHRAL ANASTOMOSIS OF RLRP Our RLRP technique has been previously described.6 Before we had performed RLRP, we were using LTcs with our pure laparoscopic prostatectomy technique. Because of surgeon preference, we have continued using the clips for the robotic technique. The vesicourethral anastomosis was performed using a double-armed, van Velthoven suture7 composed of 3-0 Vicryl and 3-0 Monocryl, each 6 in. in length and connected at the terminal ends by a hand knot and LTc. The anastomosis was begun at the posterior bladder neck (6-o’clock position), running the left arm of the suture toward the 11-o’clock position. On completion, the suture line was cinched with an LTc at the level of the tissue. The same sequence was repeated on the right side. The assistant delivered constant tension on the suture with a grasper as the surgeon ran each respective bite until the LTc was placed. In all cases, the bladder was then filled with 120 mL of saline to verify a watertight closure. Postoperative complications related to the vesicourethral anastomosis, such as urinary leakage, bladder neck contracture, and urinary retention, were assessed.
TECHNIQUE TO MINIMIZE KNOT TYING DURING LP After dismembered pyeloplasty, a 6-in. 3-0 Vicryl suture was anchored at the spatulated ureteral apex and free-hand sutured to the lateral apex of the renal pelvis opening. The posterior wall of the renal pelvis was then sutured in a running fashion over a ureteral stent and secured with an LTc. The anterior closure was performed in the same sequence. If a UROLOGY 68 (3), 2006
RESULTS The perioperative variables of the patients who underwent LPN are presented in Table I. The mean tumor size was 2.53 cm (range 1.2 to 8.5). The overall mean estimated blood loss was 189 mL. The mean WIT was 30.1 minutes (range 13 to 55). In 44 (64%) of 69 patients, the collecting system was entered while excising the renal tumor. In this subset group of patients, the mean WIT was 34.6 minutes. In the remaining 25 patients who only required closure of the renal parenchyma, the mean WIT was 26.4 minutes. Four patients (5.3%) bled intraoperatively and required urgent open conversion. Of these 4 patients, 1 had a renal artery injury and one procedure was attempted on a complex Bosniak 3 renal cyst with no hilar clamping. Three patients (4%) bled postoperatively, two immediately in the recovery room, who required urgent open exploration and completion nephrectomy, and one on postoperative day 2 who stabilized after transfusion of 2 U of blood. Two patients (2.6%) had urine leaks in our series; both were treated conservatively with prolonged drainage. One patient had a positive surgical margin, and the procedure was converted intraoperatively to open partial nephrectomy. One other intraoperative conversion was required because of a tumor location adjacent to the hilar vessels. The perioperative variables for the RLRP group are also presented in Table I. The mean operative time in our series was 295 minutes, with a mean estimated blood loss of 303.6 mL. Seven patients required open conversion: two because of bleeding, two because of poor tissue dissection, one because of bladder perforation, one because of rectal injury, and one because of a bladder urothelial tumor at the bladder neck. All such conversions occurred within the learning curve of the initial 40 cases. The mean hospital stay was 1.53 days. The Foley catheter was removed at a mean of 6.1 days postoperatively. Cystography was routinely performed in the first 30 patients in our series. Thereafter, the Foley catheter was removed on postoperative day 6. Cystography was only performed in those patients in whom prolonged drainage was noted. Overall, 3 patients had postoperative urinary leakage (1%) detected by cystography. One patient had initially developed a urine leak more than 2 days after surgery. The cystographic findings on postoperative day 7 were normal; therefore, the urinary catheter and abdominal drain 509
TABLE I. Perioperative variables of patients who underwent LPN, RLRP, and LP Variable Patients Preoperative data Mean age (yr) Sex Male Female Laterality Left Right Mean tumor size (cm) Stage cT1c cT2a cT3b Mean PSA (ng/mL) Gleason score 5–6 7 8 9 Operative data Mean surgical time (min) Mean EBL (mL) Open conversion Major bleeding Approach Transperitoneal Retroperitoneal Collecting system repair WIT (min) Total Range Collecting system repair Yes No Postoperative data Hospital stay (days) Foley catheter (days) Complications Urine leak Bleeding BNC Urinary retention
LPN
RLRP
LP
75
300
14
60.9 (23–83)
59.3 (42–74)
37 38
300 —
8 6
— —
7 7
31 44 2.53 (1.2–8.5)
38 (22–61)
236 (78.7%) 50 (16.7%) 14 (4.6%) 6.3 (0.6–32) 236 (78.7%) 57 (19%) 5 (1.7%) 2 (0.6%) 242 (111–504) 189 mL (10–600) 6 (8%) 4 (5.3%)
295* (143–525) 303.6* (10–800) 7 (2.3%) 2 (0.7%)
224 (170–460) 36 (10–100) 0 0
67 8 44 (58.6%) 30.1 13–55 34.6 26.4 2.7 (1–15) NA 2 (2.7%) 3 (4%)
1.53 (1–9) 6.1 3 (1%) 3 (1%) 4 (1.4%) 3 (1%)
1.8 (1–3) NA 0 1 (7.1%)
KEY: LPN ⫽ laparoscopic partial nephrectomy; RLRP ⫽ robotic laparoscopic radical prostatectomy; LP ⫽ laparoscopic pyeloplasty; PSA ⫽ prostate-specific antigen; EBL ⫽ estimated blood loss; WIT ⫽ warm ischemia time. * Excluded open conversion cases and sural nerve grafting.
were removed at that time. Two patients demonstrated a very small leak on initial cystography. The catheter was removed on postoperative day 10 and 13, after a repeat study with normal findings. Four patients (1%) developed bladder neck contractures requiring endoscopic management. The perioperative details for the LP group are presented in Table I. Four patients had undergone previous retrograde endopyelotomy as their primary treatment. All cases were performed transperitoneally, with a mean operative time of 224 510
minutes (range 170 to 460) and a mean estimated blood loss of 36 mL (range 7 to 100). Seven patients (50%) had crossing vessels. No intraoperative complications of bleeding or open conversions occurred. No postoperative urinary leaks developed. One patient had postoperative bleeding treated conservatively. At a mean follow-up of 14 months, all patients had had symptom improvement and had improved to stable renal function on their 3-month mercaptotriglycylglycine renal scan. UROLOGY 68 (3), 2006
FIGURE 1. Laparoscopic repair during partial nephrectomy. (A) Placement of LTc on suture that is placed under tension in line with capsular surface. (B) Intracorporeal knot that, when fastened, delivers upward forces perpendicular to capsular surface. These forces (arrows) may tear through parenchyma (cheese slicing).
COMMENT In the past decade, numerous refinements in instrumentation and surgical techniques have allowed for wider application of laparoscopic surgery. Even though ablative laparoscopic techniques have become increasingly more common, the widespread use of reconstructive laparoscopy is still evolving. This is because of the high level of difficulty related to intracorporeal suturing and knot tying in procedures such as LPN, LRP, RLRP, and LP. For LPN, reconstructive surgery is performed during WIT, the most critical portion of the procedure. During this time, tumor excision and precise suturing must be completed within a 30-minute period before the renal parenchyma may sustain damage.8 Conventional closure of the collecting system and the renal parenchyma is performed with sutures that are tied intracorporeally.9 However, intracorporeal knot tying is time consuming and may result in prolonged WIT. In addition, with conventional knot tying, because the knots are fastened onto the renal parenchyma with an upward force, a “cheese-slicing” effect can occur in which the sutures may cut through the renal parenchyma, causing more bleeding (Fig. 1). Worse yet, the sutures can tear out completely during fastening of the knot. Using the LTc to cinch down on the renal parenchymal defect closure with one throw avoids this cheese-slicing effect. The force required to oppose the tissue is parallel to the kidney rather than tangential. However, one needs to perform the cinching with great care, because overdue force may pull the LTc through the renal parenchyma. During laparoscopic intracorporeal knot tying, the knot may loosen before the second knot is laid down, resulting in a loose suture. This will result in inefficient time consumption during warm ischemia. In the case in which further cinching is needed, placing an additional LTc proximal along UROLOGY 68 (3), 2006
the same suture allows for collecting system coaptation and parenchymal compression. Such a maneuver cannot be done once a square knot has been fastened with conventional knot tying. Thus, using the LTc, we could avoid many of these potential problems while achieving rapid closure of the renal defect. In our series, we used our knot-free method for repair of the collecting system and renal parenchyma in patients undergoing LPN. Our overall mean WIT was 30.1 minutes in a group of patients with a mean tumor size of 2.53 cm. Collecting system closure was required in 58.6% of all patients. Such results compared equally with those of other groups in which conventional suturing was performed. In a recent publication by Moinzadeh et al.,10 the WIT was 27 minutes in a group of 100 patients with a mean tumor size of 2.9 cm, and 65% required pelvicaliceal closure. Despite similar WITs, it was difficult to isolate the effect of LTcs on improving the operative time. Other factors such as tumor size and location, the need for collecting system closure, and the use of additional hemostatic techniques such as Surgicel bolsters, argon laser coagulation and FloSeal, as well as surgical experience, must be considered. Although we did not have a cohort of patients in which knot tying was performed to compare the WITs, we did demonstrate low postoperative complication rates related to collecting system and parenchymal closure. Postoperatively, 2 patients had urinary leakage (2.6%) and 3 had postoperative bleeding (4%). Four patients had uncontrollable bleeding intraoperatively and required urgent open conversion (5.3%). These complications compared favorably with other groups in which acute or delayed hemorrhage and urinary leakage was reported to be as great as 9.5% and 4.5%, respectively.10,11 511
During laparoscopic radical prostatectomy, most surgeons use a double-arm continuous running anastomosis.12 Appropriate tension must be maintained on the suture for watertight closure. Tension may be lost when the surgeon performs intracorporeal knot tying when throwing the knot. Similarly, because of the inability of the robot to transmit tactile sensation, it is difficult for the surgeon to judge the ideal suture tension. These factors may lead to postoperative urinary leakage. In our series, the assistant was able to follow the surgeon and keep a constant tension on the suture until it was ready to be locked with an LTc. The LTc was applied with a handheld device that allows the assistant surgeon to appreciate the tissue resistance and suture tension. In the event the first LTc was inadequately placed, the tension can be increased by the application of a second, more proximal clip. We have performed all vesicourethral anastomoses in this fashion. Although we have been unable to demonstrate quicker anastomosis times, our technique with the LTc has demonstrated low anastomotic complication rates. The Foley catheters were removed at a mean of 6.1 days. Our urine leak rate of 1% compared favorably with those of published RLRP series at 8.9% to 10%.13,14 Similarly, we report a very low bladder neck contracture rate of 1.4%. In our LP series, 14 successful dismembered pyeloplasties were performed without complications or postoperative urinary leakage. Our results compare with those of contemporary series. The most recent and largest published series to date, from Johns Hopkins, reviewed their experience of 147 LPs between 1993 and 2000. With a mean follow-up of 24 months, the overall success rate for all patients with primary ureteropelvic junction obstruction was 95%.15 Complications were noted in 11 patients, of whom 2 had urinary leakage (1.35%). The ability to quickly and reliably provide the ideal suture tension for collecting system closure may explain the lack of urinary leakage in our group. Some may be concerned about the potential for calculus formation using the LTc. However, the absorbable clip is never in contact with the urine. It simply rests on the outer aspect of the tissue. One report of a ureteral pseudodiverticulum with the LTc has been published16; however, such an event occurred in a patient who had previously undergone laparoscopic nondismembered pyeloplasty and antegrade endopyelotomy, complicated by postoperative bacteruria and funguria. Dismembered pyeloplasty was then performed, again with the use of the LTc, and was complicated by anastomotic extravasation and infection. As such, we believe the LTc can be safely used in all patients with primary and uncomplicated secondary uret512
eropelvic junction obstruction. In patients in whom the initial treatment has been fraught with infection, leading to poor tissue quality at reconstruction, the use of the LTc should be avoided. Finally, it must be noted that the LTc can be used in other instances of reconstructive laparoscopic surgery when knot tying is needed. A 4-0 Prolene suture with an LTc placed at the end can be used to quickly and efficiently repair venous injuries, limiting blood loss. In our experience, a 1-cm vena caval laceration during retroperitoneal pelvic lymph node dissection and a 5-mm laceration in a left iliac vein during pelvic lymph node dissection were safely and rapidly repaired using this method. Using conventional knot tying methods could potentially take longer and increase the blood loss. We have also used this method for bladder closure after partial cystectomy in 2 cases. Our study had limitations. Because of the retrospective nature of the study, a comparative analysis between a control group and randomization were not possible. Selection bias may have played a role in the LP group. However, the data were all inclusive, and no patients were excluded. Because of the lack of a cohort of patients in whom conventional knot tying was used, we were unable to demonstrate a shorter WIT or faster vesicourethral anastomosis or ureteropelvic junction reconstruction time in our patients. We have demonstrated in our series that one of the most technically challenging tasks, intracorporeal knot tying, can be safely and efficiently supplemented by a simpler method. Using LTcs, we have shown that we can secure the collecting system and achieve parenchymal hemostasis in LPN and create a watertight vesicourethral anastomosis in LRP and LP. The LTc allows the surgeon the ability to adjust suture tension, unlike during knot tying. Although we were unable to demonstrate a clear time advantage with the use of the LTc, our results favor low complication rates related to hemostasis and watertight urothelial closure. The LTc system does not, however, eliminate the need for intracorporeal knottying skills. LTc supplements this invaluable skill. We believe this method may make difficult reconstructive laparoscopic procedures easier to perform for urologists embarking on these procedures. CONCLUSIONS Our results have shown that the use of the LTc simplifies and allows safe and efficient performance of complex urologic laparoscopic procedures. It may allow more urologists to embark on reconstructive laparoscopic procedures with confidence. We believe it is an essential aspect of the UROLOGY 68 (3), 2006
surgical setup for laparoscopic surgery, in addition to the surgical skill of intracorporeal knot tying. REFERENCES 1. DeKernion J: “Management of Renal Cell Carcinoma” plenary session. Presented at the American Urological Association Annual Meeting, San Francisco, California, May 8 –13, 2004. 2. Clayman RV, Kavoussi LR, Soper NJ, et al: Laparoscopic nephrectomy. N Engl J Med 324: 1370 –1371, 1991. 3. Andrews SM, and Lewis JL: Laparoscopic knot substitutes: an assessment of techniques of securing sutures through the laparoscope. Endosc Surg Allied Technol 2: 62– 65, 1994. 4. Anderson KR, and Clayman RV: Laparoscopic lower urinary tract reconstruction. World J Urol 18: 349 –354, 2000. 5. Orvieto MA, Chien GW, Laven B, et al: Eliminating knot tying during warm ischemia time for laparoscopic partial nephrectomy. J Urol 172: 2292–2295, 2004. 6. Chien GW, Orvieto MA, Galocy RM, et al: Antegrade nerve preservation during robotic assisted laparoscopic radical prostatectomy. Video presented at the American Urological Association Annual Meeting, San Francisco, California, May 8 –13, 2004. 7. van Velthoven RF, Ahlerigh TE, Peltier A, et al: Technique for laparoscopic running urethrovesical anastomosis: the single knot method. Urology 61: 699 –702, 2003. 8. Novick AC: Renal hypothermia: in vivo and ex vivo. Urol Clin North Am 10: 637– 644, 1983.
UROLOGY 68 (3), 2006
9. Gill IS, Desai MM, Kaouk JH, et al: Laparoscopic partial nephrectomy for renal tumor: duplicating open techniques. J Urol 167: 469 – 471, 2002. 10. Moinzadeh A, Gill IS, Finelli A, et al: Laparoscopic partial nephrectomy: 3-year followup. J Urol 175: 459 – 462, 2006. 11. Gill IS, Matin SF, Desai MM, et al: Comparative analysis of laparoscopic versus open partial nephrectomy for renal tumors in 200 patients. J Urol 170: 64 – 68, 2003. 12. Hoznek A, Salomon L, Rabii R, et al: Vesicourethral anastomosis during laparoscopic radical prostatectomy: the running suture method. J Endourol 14: 749 –753, 2000. 13. Ahlering TE, Skarecky D, Lee D, et al: Successful transfer of open surgical skills to a laparoscopic environment using a robotic interface: initial experience with laparoscopic radical prostatectomy. J Urol 170: 1738 –1741, 2003. 14. Bentas W, Wolfram M, Jones J, et al: Robotic technology and the translation of open radical prostatectomy to laparoscopy: the early Frankfurt experience with robotic radical prostatectomy and one year follow-up. Eur Urol 44: 175–181, 2003. 15. Inagaki T, Rha KH, Ong AM, et al: Laparoscopic pyeloplasty: current status. BJU Int 92(suppl 2): 102–105, 2005. 16. Finley DS, Perer E, Eichel L, et al: Ureteral pseudodiverticulum associated with absorbable suture clips after laparoscopic pyeloplasty: case report. J Endourol 19: 726 –729, 2005.
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MINIMIZING KNOT TYING DURING RECONSTRUCTIVE LAPAROSCOPIC UROLOGY ARIEH L. SHALHAV, MARCELO A. ORVIETO, GARY W. CHIEN, ALBERT A. MIKHAIL, GREGORY P. ZAGAJA, AND KEVIN C. ZORN
ABSTRACT 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. UROLOGY 68: 508–513, 2006. © 2006 Elsevier Inc.
L
aparoscopic radical nephrectomy has rapidly evolved into the standard of care for patients with localized renal tumors1 since its introduction in 1991.2 However, reconstructive laparoscopic surgery in which substantial knot tying is necessary, such as laparoscopic partial nephrectomy (LPN), laparoscopic radical prostatectomy (LRP), and laparoscopic pyeloplasty (LP), has had slower adoption rates in the urologic community. This has largely been because of the high level of difficulty related to these procedures. In this study, we present a modification to simplify these procedures using the Lapra-Ty clip (LTc; Ethicon EndosurFrom the Section of Urology, University of Chicago Pritzker School of Medicine, Chicago, Illinois Reprint requests: Kevin C. Zorn, M.D., Section of Urology, Department of Surgery, University of Chicago Pritzker School of Medicine, 5841 South Maryland Avenue, MC6038 J-653, Chicago, IL 60637. E-mail: [email protected] Submitted: December 20, 2005, accepted (with revisions): March 29, 2006 © 2006 ELSEVIER INC. 508
ALL RIGHTS RESERVED
gery, Piscataway, NJ) during knot tying. The LTc is designed to substitute for a knot,3 thereby minimizing intracorporeal knot tying. It also reduces the “cheese slicing” effect of the suture when cinching a knot, such as can occur during conventional knot tying. In contrast to knot tying, the LTc also permits the surgeon to apply additional tension if needed. The clip is composed of absorbable polydioxanone and can be applied to a single strand of 1-0, 2-0, 3-0, or 4-0 suture. The clip maintains tensile strength for 14 days and is completely absorbed by 90 days.4 We assessed the feasibility and specific complication rates related to the use of the LTc in all LPN, robotic LRP (RLRP), and LP procedures performed at our institution. MATERIAL AND METHODS All data were retrospectively reviewed with the approval of the institutional review board. From October 2002 to July 2005, 75 patients underwent LPN for clinical Stage T1a (n ⫽ 67), T1b (n ⫽ 7), or T2 (n ⫽ 1) renal tumors. A single surgeon (A.L.S.) per0090-4295/06/$32.00 doi:10.1016/j.urology.2006.03.071
formed all LPN and LP procedures. A total of 300 patients underwent RLRP from February 2003 to July 2005. Two surgeons (A.L.S. and G.P.Z.) performed all procedures. Finally, 14 patients underwent LP from November 2003 to July 2005; all procedures were performed by one surgeon (A.L.S.).
defect remained in the renal pelvis, it was closed using additional suture. Similar postoperative drain management as that for the LPN group was used for the LP group. Perioperative complications related to the collecting system closure, such as urinary leakage and bleeding, were assessed.
TECHNIQUE FOR MINIMIZING KNOT TYING DURING LPN Our technique for eliminating knot tying during LPN has been previously described.5 In brief, 6-in. 2-0 Vicryl sutures (coated polyglactin 910) on CT-1 needles and 6-in. 3-0 Vicryl sutures on SH needles with an LTc at the tail end of each suture were used. After tumor excision and argon beam coagulation, the 3-0 sutures were used to close the collecting system and open-ended vessels. If any suspicion regarding margin status was present, deep tumor bed biopsies were sent for frozen section analysis. Once a figure-of-eight or running suture was completed, the needle end of the suture was cinched to the desired tension and a second LTc was placed on the suture at the level of the tissue. The renal parenchymal defect was then repaired using 2-0 Vicryl sutures starting at the capsular surface. Once the desired tissue compression was achieved, a second LTc was cinched down to the level of the tissue. Sometimes, additional tension might be needed on the suture to ensure hemostatic compression. Another LTc can be applied more proximally to provide additional tension. FloSeal (Fusion Medical Technologies, Mountain View, Calif) was then applied to the exposed defect. Excess tension should be avoided, especially with the additional tension that will be created by unclamping the renal artery. This auto-tension is created by the increased tissue turgor related to the return of blood flow. Standard postoperative drain management included routine removal of the Foley catheter the morning after surgery, with the Jackson-Pratt drain removed later that same afternoon if no increased output was noted. The warm ischemia time (WIT) and postoperative complications related to the use of the LTc, such as urinary leak and bleeding, were assessed.
TECHNIQUE TO MINIMIZE KNOT TYING DURING VESICOURETHRAL ANASTOMOSIS OF RLRP Our RLRP technique has been previously described.6 Before we had performed RLRP, we were using LTcs with our pure laparoscopic prostatectomy technique. Because of surgeon preference, we have continued using the clips for the robotic technique. The vesicourethral anastomosis was performed using a double-armed, van Velthoven suture7 composed of 3-0 Vicryl and 3-0 Monocryl, each 6 in. in length and connected at the terminal ends by a hand knot and LTc. The anastomosis was begun at the posterior bladder neck (6-o’clock position), running the left arm of the suture toward the 11-o’clock position. On completion, the suture line was cinched with an LTc at the level of the tissue. The same sequence was repeated on the right side. The assistant delivered constant tension on the suture with a grasper as the surgeon ran each respective bite until the LTc was placed. In all cases, the bladder was then filled with 120 mL of saline to verify a watertight closure. Postoperative complications related to the vesicourethral anastomosis, such as urinary leakage, bladder neck contracture, and urinary retention, were assessed.
TECHNIQUE TO MINIMIZE KNOT TYING DURING LP After dismembered pyeloplasty, a 6-in. 3-0 Vicryl suture was anchored at the spatulated ureteral apex and free-hand sutured to the lateral apex of the renal pelvis opening. The posterior wall of the renal pelvis was then sutured in a running fashion over a ureteral stent and secured with an LTc. The anterior closure was performed in the same sequence. If a UROLOGY 68 (3), 2006
RESULTS The perioperative variables of the patients who underwent LPN are presented in Table I. The mean tumor size was 2.53 cm (range 1.2 to 8.5). The overall mean estimated blood loss was 189 mL. The mean WIT was 30.1 minutes (range 13 to 55). In 44 (64%) of 69 patients, the collecting system was entered while excising the renal tumor. In this subset group of patients, the mean WIT was 34.6 minutes. In the remaining 25 patients who only required closure of the renal parenchyma, the mean WIT was 26.4 minutes. Four patients (5.3%) bled intraoperatively and required urgent open conversion. Of these 4 patients, 1 had a renal artery injury and one procedure was attempted on a complex Bosniak 3 renal cyst with no hilar clamping. Three patients (4%) bled postoperatively, two immediately in the recovery room, who required urgent open exploration and completion nephrectomy, and one on postoperative day 2 who stabilized after transfusion of 2 U of blood. Two patients (2.6%) had urine leaks in our series; both were treated conservatively with prolonged drainage. One patient had a positive surgical margin, and the procedure was converted intraoperatively to open partial nephrectomy. One other intraoperative conversion was required because of a tumor location adjacent to the hilar vessels. The perioperative variables for the RLRP group are also presented in Table I. The mean operative time in our series was 295 minutes, with a mean estimated blood loss of 303.6 mL. Seven patients required open conversion: two because of bleeding, two because of poor tissue dissection, one because of bladder perforation, one because of rectal injury, and one because of a bladder urothelial tumor at the bladder neck. All such conversions occurred within the learning curve of the initial 40 cases. The mean hospital stay was 1.53 days. The Foley catheter was removed at a mean of 6.1 days postoperatively. Cystography was routinely performed in the first 30 patients in our series. Thereafter, the Foley catheter was removed on postoperative day 6. Cystography was only performed in those patients in whom prolonged drainage was noted. Overall, 3 patients had postoperative urinary leakage (1%) detected by cystography. One patient had initially developed a urine leak more than 2 days after surgery. The cystographic findings on postoperative day 7 were normal; therefore, the urinary catheter and abdominal drain 509
TABLE I. Perioperative variables of patients who underwent LPN, RLRP, and LP Variable Patients Preoperative data Mean age (yr) Sex Male Female Laterality Left Right Mean tumor size (cm) Stage cT1c cT2a cT3b Mean PSA (ng/mL) Gleason score 5–6 7 8 9 Operative data Mean surgical time (min) Mean EBL (mL) Open conversion Major bleeding Approach Transperitoneal Retroperitoneal Collecting system repair WIT (min) Total Range Collecting system repair Yes No Postoperative data Hospital stay (days) Foley catheter (days) Complications Urine leak Bleeding BNC Urinary retention
LPN
RLRP
LP
75
300
14
60.9 (23–83)
59.3 (42–74)
37 38
300 —
8 6
— —
7 7
31 44 2.53 (1.2–8.5)
38 (22–61)
236 (78.7%) 50 (16.7%) 14 (4.6%) 6.3 (0.6–32) 236 (78.7%) 57 (19%) 5 (1.7%) 2 (0.6%) 242 (111–504) 189 mL (10–600) 6 (8%) 4 (5.3%)
295* (143–525) 303.6* (10–800) 7 (2.3%) 2 (0.7%)
224 (170–460) 36 (10–100) 0 0
67 8 44 (58.6%) 30.1 13–55 34.6 26.4 2.7 (1–15) NA 2 (2.7%) 3 (4%)
1.53 (1–9) 6.1 3 (1%) 3 (1%) 4 (1.4%) 3 (1%)
1.8 (1–3) NA 0 1 (7.1%)
KEY: LPN ⫽ laparoscopic partial nephrectomy; RLRP ⫽ robotic laparoscopic radical prostatectomy; LP ⫽ laparoscopic pyeloplasty; PSA ⫽ prostate-specific antigen; EBL ⫽ estimated blood loss; WIT ⫽ warm ischemia time. * Excluded open conversion cases and sural nerve grafting.
were removed at that time. Two patients demonstrated a very small leak on initial cystography. The catheter was removed on postoperative day 10 and 13, after a repeat study with normal findings. Four patients (1%) developed bladder neck contractures requiring endoscopic management. The perioperative details for the LP group are presented in Table I. Four patients had undergone previous retrograde endopyelotomy as their primary treatment. All cases were performed transperitoneally, with a mean operative time of 224 510
minutes (range 170 to 460) and a mean estimated blood loss of 36 mL (range 7 to 100). Seven patients (50%) had crossing vessels. No intraoperative complications of bleeding or open conversions occurred. No postoperative urinary leaks developed. One patient had postoperative bleeding treated conservatively. At a mean follow-up of 14 months, all patients had had symptom improvement and had improved to stable renal function on their 3-month mercaptotriglycylglycine renal scan. UROLOGY 68 (3), 2006
FIGURE 1. Laparoscopic repair during partial nephrectomy. (A) Placement of LTc on suture that is placed under tension in line with capsular surface. (B) Intracorporeal knot that, when fastened, delivers upward forces perpendicular to capsular surface. These forces (arrows) may tear through parenchyma (cheese slicing).
COMMENT In the past decade, numerous refinements in instrumentation and surgical techniques have allowed for wider application of laparoscopic surgery. Even though ablative laparoscopic techniques have become increasingly more common, the widespread use of reconstructive laparoscopy is still evolving. This is because of the high level of difficulty related to intracorporeal suturing and knot tying in procedures such as LPN, LRP, RLRP, and LP. For LPN, reconstructive surgery is performed during WIT, the most critical portion of the procedure. During this time, tumor excision and precise suturing must be completed within a 30-minute period before the renal parenchyma may sustain damage.8 Conventional closure of the collecting system and the renal parenchyma is performed with sutures that are tied intracorporeally.9 However, intracorporeal knot tying is time consuming and may result in prolonged WIT. In addition, with conventional knot tying, because the knots are fastened onto the renal parenchyma with an upward force, a “cheese-slicing” effect can occur in which the sutures may cut through the renal parenchyma, causing more bleeding (Fig. 1). Worse yet, the sutures can tear out completely during fastening of the knot. Using the LTc to cinch down on the renal parenchymal defect closure with one throw avoids this cheese-slicing effect. The force required to oppose the tissue is parallel to the kidney rather than tangential. However, one needs to perform the cinching with great care, because overdue force may pull the LTc through the renal parenchyma. During laparoscopic intracorporeal knot tying, the knot may loosen before the second knot is laid down, resulting in a loose suture. This will result in inefficient time consumption during warm ischemia. In the case in which further cinching is needed, placing an additional LTc proximal along UROLOGY 68 (3), 2006
the same suture allows for collecting system coaptation and parenchymal compression. Such a maneuver cannot be done once a square knot has been fastened with conventional knot tying. Thus, using the LTc, we could avoid many of these potential problems while achieving rapid closure of the renal defect. In our series, we used our knot-free method for repair of the collecting system and renal parenchyma in patients undergoing LPN. Our overall mean WIT was 30.1 minutes in a group of patients with a mean tumor size of 2.53 cm. Collecting system closure was required in 58.6% of all patients. Such results compared equally with those of other groups in which conventional suturing was performed. In a recent publication by Moinzadeh et al.,10 the WIT was 27 minutes in a group of 100 patients with a mean tumor size of 2.9 cm, and 65% required pelvicaliceal closure. Despite similar WITs, it was difficult to isolate the effect of LTcs on improving the operative time. Other factors such as tumor size and location, the need for collecting system closure, and the use of additional hemostatic techniques such as Surgicel bolsters, argon laser coagulation and FloSeal, as well as surgical experience, must be considered. Although we did not have a cohort of patients in which knot tying was performed to compare the WITs, we did demonstrate low postoperative complication rates related to collecting system and parenchymal closure. Postoperatively, 2 patients had urinary leakage (2.6%) and 3 had postoperative bleeding (4%). Four patients had uncontrollable bleeding intraoperatively and required urgent open conversion (5.3%). These complications compared favorably with other groups in which acute or delayed hemorrhage and urinary leakage was reported to be as great as 9.5% and 4.5%, respectively.10,11 511
During laparoscopic radical prostatectomy, most surgeons use a double-arm continuous running anastomosis.12 Appropriate tension must be maintained on the suture for watertight closure. Tension may be lost when the surgeon performs intracorporeal knot tying when throwing the knot. Similarly, because of the inability of the robot to transmit tactile sensation, it is difficult for the surgeon to judge the ideal suture tension. These factors may lead to postoperative urinary leakage. In our series, the assistant was able to follow the surgeon and keep a constant tension on the suture until it was ready to be locked with an LTc. The LTc was applied with a handheld device that allows the assistant surgeon to appreciate the tissue resistance and suture tension. In the event the first LTc was inadequately placed, the tension can be increased by the application of a second, more proximal clip. We have performed all vesicourethral anastomoses in this fashion. Although we have been unable to demonstrate quicker anastomosis times, our technique with the LTc has demonstrated low anastomotic complication rates. The Foley catheters were removed at a mean of 6.1 days. Our urine leak rate of 1% compared favorably with those of published RLRP series at 8.9% to 10%.13,14 Similarly, we report a very low bladder neck contracture rate of 1.4%. In our LP series, 14 successful dismembered pyeloplasties were performed without complications or postoperative urinary leakage. Our results compare with those of contemporary series. The most recent and largest published series to date, from Johns Hopkins, reviewed their experience of 147 LPs between 1993 and 2000. With a mean follow-up of 24 months, the overall success rate for all patients with primary ureteropelvic junction obstruction was 95%.15 Complications were noted in 11 patients, of whom 2 had urinary leakage (1.35%). The ability to quickly and reliably provide the ideal suture tension for collecting system closure may explain the lack of urinary leakage in our group. Some may be concerned about the potential for calculus formation using the LTc. However, the absorbable clip is never in contact with the urine. It simply rests on the outer aspect of the tissue. One report of a ureteral pseudodiverticulum with the LTc has been published16; however, such an event occurred in a patient who had previously undergone laparoscopic nondismembered pyeloplasty and antegrade endopyelotomy, complicated by postoperative bacteruria and funguria. Dismembered pyeloplasty was then performed, again with the use of the LTc, and was complicated by anastomotic extravasation and infection. As such, we believe the LTc can be safely used in all patients with primary and uncomplicated secondary uret512
eropelvic junction obstruction. In patients in whom the initial treatment has been fraught with infection, leading to poor tissue quality at reconstruction, the use of the LTc should be avoided. Finally, it must be noted that the LTc can be used in other instances of reconstructive laparoscopic surgery when knot tying is needed. A 4-0 Prolene suture with an LTc placed at the end can be used to quickly and efficiently repair venous injuries, limiting blood loss. In our experience, a 1-cm vena caval laceration during retroperitoneal pelvic lymph node dissection and a 5-mm laceration in a left iliac vein during pelvic lymph node dissection were safely and rapidly repaired using this method. Using conventional knot tying methods could potentially take longer and increase the blood loss. We have also used this method for bladder closure after partial cystectomy in 2 cases. Our study had limitations. Because of the retrospective nature of the study, a comparative analysis between a control group and randomization were not possible. Selection bias may have played a role in the LP group. However, the data were all inclusive, and no patients were excluded. Because of the lack of a cohort of patients in whom conventional knot tying was used, we were unable to demonstrate a shorter WIT or faster vesicourethral anastomosis or ureteropelvic junction reconstruction time in our patients. We have demonstrated in our series that one of the most technically challenging tasks, intracorporeal knot tying, can be safely and efficiently supplemented by a simpler method. Using LTcs, we have shown that we can secure the collecting system and achieve parenchymal hemostasis in LPN and create a watertight vesicourethral anastomosis in LRP and LP. The LTc allows the surgeon the ability to adjust suture tension, unlike during knot tying. Although we were unable to demonstrate a clear time advantage with the use of the LTc, our results favor low complication rates related to hemostasis and watertight urothelial closure. The LTc system does not, however, eliminate the need for intracorporeal knottying skills. LTc supplements this invaluable skill. We believe this method may make difficult reconstructive laparoscopic procedures easier to perform for urologists embarking on these procedures. CONCLUSIONS Our results have shown that the use of the LTc simplifies and allows safe and efficient performance of complex urologic laparoscopic procedures. It may allow more urologists to embark on reconstructive laparoscopic procedures with confidence. We believe it is an essential aspect of the UROLOGY 68 (3), 2006
surgical setup for laparoscopic surgery, in addition to the surgical skill of intracorporeal knot tying. REFERENCES 1. DeKernion J: “Management of Renal Cell Carcinoma” plenary session. Presented at the American Urological Association Annual Meeting, San Francisco, California, May 8 –13, 2004. 2. Clayman RV, Kavoussi LR, Soper NJ, et al: Laparoscopic nephrectomy. N Engl J Med 324: 1370 –1371, 1991. 3. Andrews SM, and Lewis JL: Laparoscopic knot substitutes: an assessment of techniques of securing sutures through the laparoscope. Endosc Surg Allied Technol 2: 62– 65, 1994. 4. Anderson KR, and Clayman RV: Laparoscopic lower urinary tract reconstruction. World J Urol 18: 349 –354, 2000. 5. Orvieto MA, Chien GW, Laven B, et al: Eliminating knot tying during warm ischemia time for laparoscopic partial nephrectomy. J Urol 172: 2292–2295, 2004. 6. Chien GW, Orvieto MA, Galocy RM, et al: Antegrade nerve preservation during robotic assisted laparoscopic radical prostatectomy. Video presented at the American Urological Association Annual Meeting, San Francisco, California, May 8 –13, 2004. 7. van Velthoven RF, Ahlerigh TE, Peltier A, et al: Technique for laparoscopic running urethrovesical anastomosis: the single knot method. Urology 61: 699 –702, 2003. 8. Novick AC: Renal hypothermia: in vivo and ex vivo. Urol Clin North Am 10: 637– 644, 1983.
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9. Gill IS, Desai MM, Kaouk JH, et al: Laparoscopic partial nephrectomy for renal tumor: duplicating open techniques. J Urol 167: 469 – 471, 2002. 10. Moinzadeh A, Gill IS, Finelli A, et al: Laparoscopic partial nephrectomy: 3-year followup. J Urol 175: 459 – 462, 2006. 11. Gill IS, Matin SF, Desai MM, et al: Comparative analysis of laparoscopic versus open partial nephrectomy for renal tumors in 200 patients. J Urol 170: 64 – 68, 2003. 12. Hoznek A, Salomon L, Rabii R, et al: Vesicourethral anastomosis during laparoscopic radical prostatectomy: the running suture method. J Endourol 14: 749 –753, 2000. 13. Ahlering TE, Skarecky D, Lee D, et al: Successful transfer of open surgical skills to a laparoscopic environment using a robotic interface: initial experience with laparoscopic radical prostatectomy. J Urol 170: 1738 –1741, 2003. 14. Bentas W, Wolfram M, Jones J, et al: Robotic technology and the translation of open radical prostatectomy to laparoscopy: the early Frankfurt experience with robotic radical prostatectomy and one year follow-up. Eur Urol 44: 175–181, 2003. 15. Inagaki T, Rha KH, Ong AM, et al: Laparoscopic pyeloplasty: current status. BJU Int 92(suppl 2): 102–105, 2005. 16. Finley DS, Perer E, Eichel L, et al: Ureteral pseudodiverticulum associated with absorbable suture clips after laparoscopic pyeloplasty: case report. J Endourol 19: 726 –729, 2005.
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