Urologic laparoscopic surgery: Whether open incision is waning

AK Hemal

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Year : 2001 \| Volume : 17 \| Issue : 2 \| Page : 103-110

Urologic laparoscopic surgery: Whether open incision is waning

AK Hemal
Department of Urology, All India Institute of Medical Sciences, New Delhi, India

Correspondence Address:
A K Hemal
Department of Urology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi - 110 029
India

Source of Support: None, Conflict of Interest: None

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Keywords: Laparoscopy; Retroperitoneal Space; Kidney Tumour; Nephrectomy; Ureter; Bladder; Urolithiasis; Incontinence; Lymphocele.

How to cite this article:
Hemal A K. Urologic laparoscopic surgery: Whether open incision is waning. Indian J Urol 2001;17:103-10

How to cite this URL:
Hemal A K. Urologic laparoscopic surgery: Whether open incision is waning. Indian J Urol [serial online] 2001 [cited 2023 Feb 5];17:103-10. Available from: https://www.indianjurol.com/text.asp?2001/17/2/103/21037

Introduction

Ignored for decades by urologists, Laparoscopy has finally entered urology as a subspeciality, within a decade. The skilled laparoscopic urologist can now effectively replace many incisional procedures. This aspect of urologic surgery is rapidly developing; its potential is limited only by the urologist's imagination. In the coming years, our methods of urologic practice will change dramatically. The necessity to harm in order to heal will be supplanted by laparoscopy. Laparoscopy surgery has the advantage of endoscopic surgery (less invasive nature) and the advantage of open surgery which is used for the removal and reconstruction of various organs. Thus, transferring benefits of early postoperative recovery, less hospital stay and early recuperation. After ESWL, probably the single most important development in the field of urology has been the emergence of laparoscopic urologic surgery.

I. History

The first urologic application of laparoscopy was localization of cryptorchid testis in adults, which was reported in 1976 by Cortesi.^[1] Wickham was first to perform laparoscopic ureterolithotomies in 1979.^[2] Similarly, Schussler et al in 1991 first described laparoscopic lymphadenectomy for staging prostate cancer.^[3] However, after the first laparoscopic nephrectomy by Clayman and associates in 1990 the whole scenario changed.^[4] Since then almost all urologic procedures that were being performed by open surgery have now been described laparoscopically. Retroperitoneoscopic surgery came into vogue in 1993.^[5]

II. Access

Laparoscopic urologic procedures can be performed either transperitoneally or retroperitoneally. In the transperitoneal approach, the anterior abdominal wall musculature is traversed by anterior ports and the line of Toldt is incised to reach the kidneys. To approach the kidney retroperitoneally, laparoscopic entry is via the superior or inferior lumbar triangle. The Urologic surgery is mostly retroperitoneal and extraperitoneal as these organs are located inherently in the retroperitoneum and extroperitoneally. However, with the advent of laparoscopic surgery, urologists once again found it necessary to traverse the peritoneal cavity in order to provide their patients with the benefit of this less invasive type of surgery. Creativity and perseverance led to use of laparoscopy via retroperitoneal approach. The concept of balloon dilatation of retroperitoneum was introduced by Gaur, which subsequently led to growth of retroperitoneoscopy.^[5]

Advantages of Retroperitoneal Approach:

It can be done safely even in patients, who have undergone multiple intraperitoneal interventions previously.
Less port sites are needed as retraction can be done from one trocar only as bowel retraction is not needed.
Less operative time - In transperitoneal approach more time is required as the position of the patient has to be changed from supine to lateral position after creation of pneumoperitoneum and mobilization of gut is required before exposing the kidney.
Less operative complication - With transperitoneal approach there is risk of injury to intraperitoneal organs like bowel and spleen during retraction.
No risk of development of intraperitoneal adhesions at a later date.
No risk of spillage of infected urine and content of kidney into the peritoneal cavity.
This approach is familiar to every urologist.

Disadvantages of Retroperitoneal Approach:

Less working space available for dissection and there is difficulty in dissecting large hydronephrotic kidneys and large renal tumours. However some authors have not found it true in all cases and modifications have been suggested for such situations.^[6]
Longer learning curve.
Although there are certain advantages and disadvantages of both the approaches, in a particular patient, the ideal approach should be individualized. Both the approaches are safe and complementary to each other and sometimes even combined access can be used.

III. Indications and Contraindications

Before undertaking any laparoscopic procedure the patient should be explained the risk of the procedure. The risks include common general risks (wound infection), uncommon risks (vascular and enteric injury) and catastrophic risks (death). The patient should clearly understand that the procedure can be converted to open surgery at any point of time. List of indications and contraindications are mentioned in [Table - 1],[Table - 2].

IV. Overview of Established Laparoscopic Urological Procedures

Although many urological procedures have now been performed laparoscopically there are some which have almost established themselves in routine practice now. Such common procedures include renal cyst decortication, simple nephrectomy, radical nephrectomy, ureterolithotomy, pelvic lymph node dissection, surgery for stress urinary incontinence, surgery for undescended testis and recently donor nephrectomy. The other interesting areas emerging are laparoscopic radical prostatectomy, radical cystectomy and urinary diversions.

A) Adrenal Gland:

Laparoscopic approach to adrenal gland has been used for various benign adrenal diseases. Laparoscopic surgery for malignant adrenal diseases is still controversial. Current indication, for laparoscopic adrenalectomy include nonfunctioning adenomas, phaeochromocytoma. Cushing's disease, aldosteronoma, angiomyolipoma and medullary cysts of adrenal gland. Open surgery is recommended for large (>6cm) functioning adrenal neoplasms and malignant neoplasm. Gasman et al reported retroperitoneoscopic adrenalectomy in 8 patients.^[7] 5 patients had aldosteronoma and 3 patients had Cushing's syndrome. The average adrenal tumor size was 31 mm (range 20 to 40). The average operating time was 84 minutes (range 45 to 140), and average hospital stay was 2.4 days (range I to 4). The average blood loss was 65 ml. No patient required conversion to open surgery. No complication was reported. We have performed 18 adrenalectomies in patients with phaeochromocytoma. Conn's disease, and myelolipoma and adrenal cyst with good results.^[8]

B) Kidney and Ureter:

1. Simple Nephrectomy and Nephroureterectomy - I have performed nephrectomy and nephroureterectomy for nonfunctioning kidneys due to benign diseases in about 200 patients since 1994. The indications have included nonfunctioning kidney due to pelviureteric junction obstruction, stone disease, renovascular hypertension, and tuberculosis . These also included patients of various congenital disorders like horseshoe kidney, ectopic kidney, vesicoureteric reflux and megaureter. Our conversion rate has been 8.5%. We have been able to complete the procedure successfully even in patients on nephrostomy, patients with pyonephrosis and previously operated cases. The specimen was removed intact by extending one of the port site incision to avoid the cost of various organ entrapment sacs and tissue morcellators, beside saving on operating time.

2. Radical Nephrectomy - The indications for removal of those kidneys harbouring malignancy are clear now. These organs are best removed intact by extending the port site incision. This allows adequate staging and grading of the tumour and reduces the risk of tumour spillage or tract seeding. In general, patients with tumours < 8cms and without renal vein or caval involvement, are considered candidates for laparoscopic nephrectomy. Location of tumour in relation to kidney is not a factor to consider in removal of kidney. Ono et al have compared the results of open and laparoscopic radical nephrectomy in a group of 100 patients treated from 1992-1998.^[9] 60 patients underwent laparoscopic and 40 patients underwent open surgery. There was only one conversion in laparoscopic group. The calculated blood loss was less than in open surgery. There was faster recovery and shorter hospital stay in the laparoscopic group. Abbou et al reviewed 58 consecutive patients of radical nephrectomy.^[10] 29 underwent open radical nephrectorny and 29 underwent laparoscopic radical nephrectomy. The laparoscopic radical nephrectomy group had significantly less operative blood loss, required less pain medication, had shorter hospital stay and had less complication rate as compared to open radical nephrectomy group. They recommend that laparoscopic approach is effective and safe for tumours less than 5 cms. In our centre, we are carrying out comparison of retroperitoneoscopic radical nephrectomy with open surgical nephrectomy as a pilot study and have performed over 17 cases with successful outcome.

3. Stone disease - With the development of extracorporeal shock wave lithotripsy (ESWL) and percutaneous nephrolithotomy (PCNL) the indications of open surgery have shrunken considerably. In those patients in whom there is an indication of open surgery laparoscopic approach has been suggested. 43 ureterolithotomies and 6 pyelolithotomies have been performed in our department and these were the cases where open surgery was contemplated otherwise. This is an area, where there is great scope in our country, especially for patients presenting with large size stones. However, a comparative study is required between PCNL, and laparoscopy with long-term follow-up. Similarity, nonfunctioning kidneys due to stone disease can be nephrectomized laparoscopically without any doubt.

4. Chyluria - Operative lymphatic disconnection is indicated once conservative measures and sclerotherapy fail to cure the patient. We have performed pyelolymphatic disconnection in 7 patients and have been successful in all of them. The average operative time was 114 mts (range 95-145 mts ) and blood loss was 125 ml. There were no major complications.^[11] This is another appropriate indication for retroperitoneoscopic management.

C) Laparoscopic Lymphadenectomy:

Retroperitoneal lymphadenectomy for testicular tumour is being done effectively and successfully. Pelvic lymphadenectomy can be performed safely and expeditiously. For prostate cancer it is now being performed by both accessing extraperitoneally and transperitoneally. It has been shown in many studies that the staging effectiveness of laparoscopic approach is comparable to open procedure. It also has role for other pelvic malignancies.^[12]

D) Laparoscopic Surgery for Female Urology:

1. Incontinence procedure - Initial reports of the laparoscopic bladder neck suspension have suggested success rates similar to other traditional bladder neck suspension procedures. The currently accepted theory of continence is that increase in urethral closure pressure during stress maneuvers arise because the urethra is compressed against the hammock-like supporting layer, rather than the urethra being truly intrabdominal. Delancey suggested that the treatment of female stress urinary incontinence should focus on reconstructing this supporting tissue, not on elevating or repositioning the bladder.^[13] Some investigators have suggested that patients with anatomic stress incontinence may also have an element of intrinsic sphincteric dysfunction, which may compromise the results of the bladder neck suspension procedure. Several investigators have advocated the use of the sling urethropexy for all patients with SUI to improve long-term success rates of surgical intervention. At the present juncture isolated laparoscopic bladder neck suspension has got limited role, exclusively in patients with anatomical SUI.

2. Laparoscopic sling urethropexy - For patients presenting with type II SUI, the widely accepted technique for surgical management has been the sling urethropexy. The sling procedure can be performed laparoscopically. Urethra is dissected including periurethral tissue and sling is applied laparoscopically. Continued clinical evaluation of these patients is being maintained in an effort to determine the long-term efficacy of this surgical procedure for SUL ^[14]3. Laparoscopic management of vaginal prolapse - Massive eversion of the vagina is one of the most disturbing, frustrating, and embarrassing disorders confronting the modem woman. The incidence of the massive vaginal erosion is not well established, but it probably occurs in about 0.5% of patients who have undergone vaginal or abdominal hysterectomy. The laparoscopic approach to surgical management affords the patient a minimally invasive procedure which can duplicate the technique used at open surgery to attach the vaginal vault to the hollow of the sacrum with either autologous (fascia lata, rectus fascia, cadaveric, etc.) or synthetic (Gortex, Mersilene, or Marlex mesh, etc.) materials. The laparoscopic sacrocolpopexy technique involves a transperitoneal approach to the pelvis.^[15]

4. Laparoscopic repair of vesicovaginal and vesicoureterine fistula - Vesicovaginal fistula is a commonly encountered problem in our country. Simple supratrigonal VVF can be repaired laparosocpically by separating both bladder and vagina. Interrupted sutures can be applied on either side. An omental twig can be interposed in between. Similarily vesico-uterine fistula can also be repaired laparoscopically by separating bladder from uterus and interposing omentum in between to prevent recurrence and make sure shot repair. Author has experience of reconstructing both the conditions laparoscopically.

E) Paediatric Urology:

Laparoscopy has firmly established itself in children with nonpalpable testes. The role is to localize an intra-abdominal testis in the hope of improving incision placement and avoiding intra-abdominal exploration. Laparoscopy has been seccessful in localizing or identifying the non-palpable testis in 85-100% patients. Laparoscopy has been described for intersex patients. It allows complete visualization of pelvic structure, gonadal biopsies can be taken or gonadectomy can be done in patients where indicated. It is safe to say that anything that can be done in adults can be done in children. However, it needs to be carefully addressed to various disease processes. A great deal of debate exist over the performance of nephrectomy in small children.^[16] Pyeloplasty has been performed in children. Adrenal laparoscopic surgery has not been aggressively pursued in children at this point. Laparoscopic pyelolithotomy, pelvic node dissection, cystoprostatectomy, appendicovesicostomy, ileal conduit, ileal vaginal reconstruction, bladder diverticulectomy, ureteroneocystomy have all been done in selected children. Author has reported retroperitoneal approach for nephrectomy, nephroureterectomy and nephrectomy with isthumusectomy in 11 children without any conversion. It was concluded that it is safe and effective in children.^[17]

F) Role of Hand-Assisted Laparoscopy in Urologic Practice:

Hand-assisted laparoscopy addresses many of the contemporary concern of urologists who are contemplating performing renal laparoscopy. The return of tactile feel, finger dissection, and vascular control will facilitate laparoscopic renal surgery for many urologists. Hand assistance may shorten the learning curve and minimize intraoperative complications by allowing less-experienced laparoscopists to dissect rapidly and efficiently and to control problematic bleeding more easily. The lack of abundant "training" cases has limited many urologists from embracing urologic laparoscopy. Hand assistance allows urologists to attempt more challenging procedures sooner, thereby increasing their caseload. Similarly, hand assistance enables experienced laparoscopists to tackle more complex procedures with greater confidence than they would have while using conventional laparoscopy alone. Cost remains a concern among all practitioners of minimally invasive surgery. It remains a challenge to create a cost scenario in which laparoscopic nephrectomy has to be equal to its open counterpart. Prolonged operative time has been a critical element in the increased cost of laparoscopic nephrectomy. Devices such as the Pneumodissector, Endohand, and Endostitch were all created to hasten tissue dissection and shorten operative times. Hand assistance has been quoted in shortening operating room times.^[18]

Despite this benefit, enthusiasm for hand assistance must be tempered. Urologists must consider the restrictions of the template on port placement, curtailment of operating space as a result of having a hand in the abdomen, the time required to set up the device, and the cost. Yet in cases requiring intact specimen removal where an incision must be made (laparoscopic live-donor nephrectomy or radical nephroureterectomy), hand assistance offers significant benefits during the procedure. The first hand-assisted livedonor nephrectomy has recently been reported. Similarly, conversion to hand assistance can be benefical if there is lack of progression of the dissection during a standard laparoscopic procedure. It is clear that hand assistance belongs in the arsenal of the practising urologic laparoscopist.

G) Laparoscopic Surgery in Renal Transplantation:

The major disadvantage of living donors is that a healthy person must undergo a major surgical procedure. It is also of paramount importance that surgery poses minimum risk to the healthy patient. The disincentives associated with donation include factors such as prolonged hospitalization, postoperative pain and the cosmetic results of major abdominal surgery. The other major indication for laparoscopic surgery in renal transplant patients is in the management of posttransplant lymphoceles. The technique of laparoscopic live-donor nephrectomy in humans was first developed by Ratner et al in 1995.^[12] Since then several investigators have reported their experience with this procedure. Laparoscopic live-donor nephrectomy has resulted in decreased hospital stay, less postoperative analgesic requirements and an earlier return to normal activities. Both the transperitoneal and retroperitoneal approaches can be used to do laparoscopic live-donor nephrectomies.

As advocated by Johnson et al^[20] the risk of complications can be minimized by

Identifying the correct plane between the mesocolon and retroperitoneal structures by tracing the gonadal vein as it crosses the iliac vein to the renal vein. .
Keeping the ureterogonadal vessels complex intact throughout the length of the graft ureter in order to prevent the risk of ureteral ischemia.
Confine renal vein dissection medial to the gonadal and adrenal vein origin so as to prevent injury to the renal pelvis.
Transect the lateral attachments and the ureter after the pedicle is free. This minimizes the likelihood of torsion of the renal pedicle and urine is kept out of the field.

Conversion to open surgery may be indicated if there is uncontrolled bleeding, trauma to adjacent organs, difficult anatomy, renal ischemia during the procedure and prolonged dissection time. The author has experience of retroperitoneoscopic donor nephrectomy and the technique is described below.

Retroperitoneal procedure:

The preparation for the patient is similar to the transperitoneal procedure and the patient is positioned in the standard kidney position. A 2cm incision is made a little below and posterior to the tip of the 12th rib down the thoracolumbar fascia into the retroperitoneal space and the retroperitoneal space created using blunt finger dissection. As with the transperitoneal approach the patient is kept volume expanded and the retroperitoneal space is insufflated to a pressure of 15cms of water. This is in order to ensure good renal blood flow. The second l0mm cannula is introduced in line with the first port, a little above the iliac crest in order to avoid hindrance to the maneuverability of the cannula by the bone. A third 10mm cannula is inserted under vision, in the midaxillary line two centimeters below the costal margin. During insertion of this third port, special care needs to be taken to prevent the trocar from traversing the peritoneum. A fourth port is inserted posteriorly later in the procedure. Initially the kidney is mobilized within the Gerota's fascia, which is then incised posteriorly, and the renal pedicle is dissected starting posteriorly. The renal artery and vein are freed from their adventitial attachments. The ureter is mobilized within the periureteral sheath along with the gonadal vessels. The rest of the kidney is dissected free from within the Gerota's fascia. Prior to transection of the ureter and the ligation of the renal vascular pedicle the primary port site incision is enlarged as for a flank incision down to muscular layers except thoraco-lumbar fascia, so that following ligation the kidney can be delivered with minimum delay. Once the kidney is freed all around and the ureter transected the pedicle is ligated and the kidney delivered. Mannitol, frusemide and heparin are given as in all cases of donor nephrectomy. It is important to dissect the kidney completely without undue traction on the renal pedicle. On the delivery of the kidney subsequent management is similar to that described for the transperitoneal route.

The overall performance of the allograft, measured by posttransplant serum creatinine, urine output, incidences of acute tubular necrosis, rejection episodes and ultimate graft survival appear to be similar to the kidneys obtained by open surgery.^[21]

H. Posttransplant Lymphocele:

The other major indication of laparoscopic surgery in the management of transplant patients is in the treatment of persistent lymphoceles. The reported incidence of lymphocele formation in recipients of renal allografts is of the order of 0.5% to 18.1 %. Large and symptomatic lymphoceles may cause hydronephrosis, impaired renal function, ipsilateral leg swelling, edema overlying the graft, venous and arterial obstruction and infection. Routine post-operative ultrasound is the best method of detection of the lymphocele. The first line of management of symptomatic lymphoceles is percutaneous drainage. It is however associated with prolonged catheter drainage, risk of infection and protein loss from the lymph and a high recurrence rate (50-80%). Laparoscopic internal drainage of the lymphocele was first reported by McCullough et al in 1991.^[22] Since then the over all success rate of the procedure is around 88%. The procedure of laparoscopic internal drainage of the lymphocele is done via the transperitoneal approach after the placement of a Foley catheter and nasogastric tube. Pre-operatively the sac may be filled with methylene blue in order to delineate the lymphocele better at surgery. The ports are inserted at the umbilicus, right mid-clavicular line just below the umbilicus and the third port in the hypogastrium. After the lymphocele is identified as a bulge any adhesions over it are removed, its wall incised and the fluid aspirated. A part of the wall is then removed and the omentum fixed around the edge of the cavity. This procedure should be avoided if the lymphocele is infected. Injury to the transplanted ureter can occur during the procedure especially if the lymphocele is located posteriorly and inferiorly.^[23]

V. Complications

There are a few complications which may be encountered during laparoscopic procedures. Subcutaneous emphysema, pneumomediastinum, pneumopericardium, pneumothorax may result because of the need for CO₂ insufflation for these procedures. Gill et al reviewed the complications of laparoscopic nephrectomy done between June 1990 and July 1993 at 5 centres of USA.^[24] The procedure was done in 185 patients. A total of 30 patients (16%) had 34 complications. Access related complications included 2 cases of hernia formation at the trocar site, abdominal wall hematoma and 1 trocar injury to a hydronephrotic kidney. Intra-operative complications included 5 cases of vascular injury, 1 splenic laceration and 1 pneumothorax. Postoperative complications involved the gastrointestinal tract in 6 cases, cardiovascular system in 6, genitourinary tract in 4, respiratory system in 4 and musculoskeletal system in 2. Miscellaneous complications occurred in 3 patients. Open surgical intervention was required electively in 8 patients and on an emergency basis in 2. The incidence of complications decreased with experience 71 % occurred during the initial 20 cases at each institution. In our series of 356 patients who underwent various laparoscopic procedures at our Institute, there were 11.4% complications rate and 11.1 % conversion rate, which includes our initial learning curve and wrongly chosen cases such as xanthogranulomatous pyelonephritis, genitourinary tuberculosis, medially located pelvic kidneys, severe pyonephrosis with dense perirenal adhesions due to urolithiasis. Peritoneal rents during port placement occurred in 13 (5.4%) patients. Excessive bleeding occurred in 7 patients. The causes were common iliac artery injury, slipped clip from the renal venous stump, injury to gonadal vessels and trocar injury to renal vein. Only 2 patients with gonadal vein injury could be managed endoscopically and the other 5 patients required conversion to open surgery. 7 patients had persistent fever in the postoperative period. The cause of fever was a retroperitoneal collection in 3 patients while the other 4 had pleural effusion, basal atelectasis, subcutaneous abscess at the port site and urinary tract infection. 1 patient developed a port site hernia following nephrectomy for a pyonephrotic kidney.

VI. Conclusions

Laparoscopic urologic surgery has advanced from ablative to reconstructive surgery. Though, only few centres are doing these procedures worldwide but gradually picking up all over. More advanced laparoscopic procedures like pyeloplasty, radical prostatectomy, radical cystectomy, urethral sling, sacrocolpopexy, deal loop conduit and other urologic bowel surgery are being done by only few surgeons. However, these techniques are being adopted now. It is also important to evaluate these procedures as what is possible laparoscopically does not mean it is reasonable. Before taking up these procedures, one should be properly trained and it requires patience and skill as learning curve is often steep and long. Thus, it is evident that there is substantial scope of laparoscopic urologic surgery.The time is ripe for the urologist to learn and practice this art of surgery. With the skills of endoscopic surgery and experience of endovision camera, I for one don't see any reason, why urologists cannot take up laparoscopic surgery. Dedication, training, perserverance are required. The next century is going to be an era of minimally invasive surgery. Therefore do not miss the opportunity to learn this new art to benefit your patients.

References

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