Laparoscopic Pyeloplasty

Laparoscopic pyeloplasty has evolved into a new standard of care for the treatment of ureteropelvic junction (UPJ) obstruction. Since it was introduced in the early 1990s, the laparoscopic approach has maintained the high efficacy of open surgery without the coincident morbidity of the open incision. In addition, the approach is favored over endopyelotomy because complex reconstruction can be performed, even in the presence of aberrant crossing vessels. The surgery does require intracorporeal suturing skills, which may be perfected in an inanimate trainer before operative intervention.

Indications and Contraindications

The indications for laparoscopic pyeloplasty include documented UPJ obstruction. Preoperative three-dimensional computed tomography (CT) reconstruction of the UPJ may allow visualization of crossing vessels but is not necessary in all patients. There are few contraindications to laparoscopic pyeloplasty. With the exception of routine surgical contraindications (medical comorbidities, multiple surgeries or infections, renal or ureteral adhesions, uncorrected coagulopathies), the operation may be performed in patients of virtually any age and with any anatomic abnormality. Crossing vessels, renal stones, and duplicated collecting systems can all be addressed laparoscopically. Laparoscopic pyeloplasty may also be performed after failed endopyelotomy, failed open pyeloplasty, or even failed laparoscopic pyeloplasty.

Patient Preoperative Evaluation and Preparation

In assessing the degree of obstruction, a diuretic renal scan may help quantify blockage and residual function. An intravenous urogram or retrograde pyelogram may help define anatomic considerations before reconstruction. A CT angiogram or three-dimensional reconstruction of the UPJ may reveal anterior crossing arteries or veins that will require dismembered pyeloplasty and transposition of the vessels. None of these studies, however, is absolutely compulsory because none of them is likely to change the need for surgical intervention. Nevertheless, the studies may produce a surgical map of the field, thus allowing for less intraoperative speculation.

Obtain informed consent from the patient and discuss major risks, benefits, and alternatives. Discuss general surgical risks and other risks more germane to the procedure, including the possibility of urine leak, injury to surrounding structures, failure of surgery, migration of stents and drains, open conversion, bleeding, loss of kidney function, and nephrectomy.

Patients may have existing indwelling stents from the diagnosis of obstruction and pain. Typically, indwelling stents may cause ureteral edema and thickening, and identification of the UPJ may be difficult. Consider removing the stent 1 week before surgery if the patient can tolerate this intervention.

Give the patient a bottle of magnesium citrate and clear liquids the day before surgery. This bowel preparation, although not completely necessary, allows decompression of the intestines and may help in visualization during dissection. A negative urine culture is needed, or antibiotics are given at the time of surgery. After induction of general anesthesia, place an orogastric tube. Perform flexible or rigid cystoscopy and place a stent into the affected kidney. Use a long stent (7 French × 28 cm) so that it does not migrate out of the bladder during reconstruction. Perform a retrograde pyelogram if it is indicated. Place a urethral catheter, and reposition the patient for the pyeloplasty.

Operating Room Configuration and Patient Positioning

The operating room is configured so that the surgeon and staff have excellent views of the laparoscopic surgical monitors ( Fig. 25-1 ).

Figure 25-1

To allow visualization of the procedure by all members of the surgical team, the surgeon and assistant stand on the side contralateral to the pathology. The scrub nurse or technician stands on the opposite side to help with management of instrumentation.

Positioning can be performed in a variety of methods. If a difficult dissection is anticipated, position the patient over the break in the table in case open conversion is needed. Place the patient into the full flank position (90 degrees) or the modified flank position (60 degrees, supported by a gel roll). Place the arms high so that they do not interfere with suturing ( Fig. 25-2 ). No flexion is necessary in most cases. Consider adding an axillary roll and ensure that adequate padding is used.

Figure 25-2

The umbilicus should be centered at the table break in the event that an open repair would be performed. An axillary roll is placed under the lower arm, which is brought out perpendicular to the patient. The arms are then positioned in a “praying position” near the patient’s head and separated by a small pillow. The contralateral lower knee is bent at a 90-degree position and the ipsilateral leg is kept straight with pillows or foam placed between them. Wide cloth tape is placed across the upper shoulder and arm and the hip and secured to the operative table.

Trocar Placement

Insert a Veress needle and establish a pneumoperitoneum. Place a 10/12-mm trocar at the umbilicus, a 5-mm trocar 6 to 8 cm superior to the umbilicus, and a 10/12-mm trocar 6 to 8 cm below the umbilical trocar. Place all trocars in the midline; this positioning facilitates ergonomic suturing ( Fig. 25-3 ).

Figure 25-3

Trocar placement includes three midline trocars. A 10/12-mm trocar is placed at the umbilicus. The second port (5 mm) is placed midway between the xiphoid process and the umbilicus. A third trocar is located midway between the umbilicus and the symphysis pubis.

Procedure (See )

Use a 30-degree lens throughout the operation. Deflect the colon using standard laparoscopic techniques, similar to a radical nephrectomy, and identify the ureter. Take care not to mobilize the ureter aggressively because it is necessary to preserve the periureteric blood supply.

Expose the ureter only at the UPJ. The area can be easily found because the pelvis is typically hydronephrotic and the stented ureter can be felt with laparoscopic graspers. The gonadal vein may be mistaken for the ureter, and palpation of the structure may clarify the structure’s identity. Take care in dissection of the UPJ because a crossing vessel may be present ( Fig. 25-4 ). Once the UPJ has been identified and crossing vessels have been recognized, free the renal pelvis from its peripelvic attachments near the UPJ. This allows mobilization of the pelvis and proximal ureter for the anastomosis. Important, during the dissection of the UPJ, avoid clips because they could erode into the repair. Control bleeding with energy sources (e.g., ultrasonic shears, bipolar cautery, monopolar cautery), but avoid direct use of energy on the ureter. Control oozing at the cut edge with the sutures during repair.

Figure 25-4

After the colon is deflected, the ureter is identified at the lower pole of the kidney. A crossing vessel is identified causing obstruction at the level of the ureteropelvic junction.

Hynes-Anderson Dismembered Pyeloplasty

Once a crossing vessel is suspected during preoperative imaging or observed during the procedure itself, a Hynes-Anderson dismembered pyeloplasty is the treatment of choice. This approach can also be used in virtually any UPJ obstruction.

A segmental renal vessel can be identified in close proximity to the UPJ in up to 60% of patients, and its anterior position may be the cause of the obstruction. Perform the anastomosis between the ureter and the renal pelvis anterior to the vascular obstructing component.

When the renal pelvis is identified, mobilize it along with a small portion of the proximal ureter. Take care not to damage the small vessels supplying the pelvis; theoretically this could provide better viability of the anastomosis.

Make a circumferential incision over the renal pelvis above the anastomotic area ( Fig. 25-5 ) and insert the stent. Complete the incision around the stent and along the renal pelvis wall. Take down redundant tissue to enable better approximation and technical results. Distally transect the UPJ using laparoscopic scissors and either remove the ring of ureteral obstructing tissue or incorporate it in the spatulation. Take care not to damage the ureteral stent during this manipulation. Make a 1-cm spatulation incision along the lateral or posterior wall of the proximal ureter. Spatulate the renal pelvis, if needed. Place a 4-0 polyglactin stitch at the tip of the spatulated ureter and then through the renal pelvis.

Sep 11, 2018 | Posted by in ABDOMINAL MEDICINE | Comments Off on Laparoscopic Pyeloplasty
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