Лапароскопический доступ

Renal cancer. Contemporary management. Editor John A. Libertino. Springer New York 2013.

Laparoscopic access


Трансперитонеальный

For the transperitoneal approach, five or six trocars are generally utilized. A 12 mm incision is made at the ipsilateral border of the rectus muscle at a midpoint between the umbilicus and anterior superior iliac spine. Intraperitoneal access is obtained via Hassan (open) or Veress technique depending on surgeon preference, and pneumoperitoneum is achieved to 15 mmHg. Remaining trocars are placed under direct vision. A 12 mm subcostal port for the surgeon’s right (if left-sided tumor) or left (if right-sided tumor) hand is placed. An intervening 12 mm camera trocar is placed just medial and caudal to the subcostal trocar. A 12 mm trocar along the anterior axillary line is placed for use by the assistant. For a right-sided tumor, a 5 mm subxiphoid trocar is inserted for liver retraction (Фиг. 14.2).

Renal Cancer_ Contemporary Management-Springer New York (2013) 14.1

Фиг. 14.1. Patient positioning for left renal surgery. Таблица is maximally flexed. Patient is at 45° modified flank position. White arrows: pressure points padded at knee and hips. Black arrows: tape securing patient to bed. Arms are placed in padded double arm boards (Image courtesy of use, www.urologybook.com)

Ретроперитонеальный

For the retroperitoneal approach, the patient is in the full flank position. A 12 mm incision in the posterior axillary line between the iliac crest and tip of the 12th rib is made. Using blunt dissection, a working space is created and a blunt tip trocar is inserted through the incision. Three additional trocars are used: a 5 mm port placed at the tip of the 12th rib, a 12 mm port at the level of the umbilicus in the anterior axillary line, and a 12 mm port just superior to the umbilicus in the midaxillary line. Retroperitoneal access is best suited for posterior tumors or a patient with multiple prior abdominal procedures. The limited working space reduces visualization and makes suturing more technically challenging if performed laparoscopically. Comparisons of transperitoneal and retroperitoneal LPN have shown similar blood loss, perioperative complication rates, and postoperative creatinine.

Ассистирование руками

Hand-assisted laparoscopic (HAL) partial nephrectomy offers the benefit of tactile feedback, similar to open surgery, while maintaining a more cosmetically appealing incision. It is the authors’ preference not to employ hand assistance for partial nephrectomy cases as typically a large extraction incision is not necessary. Usually, the surgeon’s nondominant hand is inserted through a periumbilical working port. The exception is when right-handed surgeons operate on rightsided tumors, the hand incision is made in the right lower quadrant. The optimal length of the working port incision corresponds to the width of the surgeon’s hand to prevent gas escaping. Two or three additional ports are utilized and location may vary. One example of trocar placement is as follows: 12 mm camera port is placed midline between the epigastrium and umbilicus and a 10/12 mm working port in the midclavicular line lateral to the umbilicus.

Renal Cancer_ Contemporary Management-Springer New York (2013) 14.2

Фиг. 14.2. Лапароскопический доступ для правой трансперитонеальной частичной нефрэктомии. LR 5 mm liver retraction port placed subxiphoid, R right-hand working trocar, C camera trocar, L left-hand working trocar, LA 5 mm lateral assistant trocar

Процедура

Once transperitoneal access is safely obtained, the ascending (right) or descending (left) colon is mobilized medially. On the right, using blunt dissection, the hepatic flexure is mobilized and the duodenum is Kocherized. On the left side, the splenorenal, splenocolic, and splenophrenic ligaments are released, and the spleen and pancreas tail are mobilized medially. The gonadal vessels and ureter are identified and retracted laterally for left-sided renal dissection then traced proximally to the renal hilum. For right-sided procedures, the gonadal vein is preserved medially adjacent to the inferior vena cava while the ureter is retracted laterally. Significant dissection of the ureter is avoided to minimize the risk of devascularization. The renal artery and vein are dissected to allow adequate placement of clamps.

In patients with multiple veins and/or arteries, intraoperative Doppler ultrasound may be used to help identify their location. In a study of 53 consecutive patients undergoing RALPN by Hyams et al., utilization of Doppler ultrasound reduced mean hilar dissection time and aided in the detection of accessory vessels not seen on preoperative imaging. Gerota’s fascia is then incised and the tumor is identified. If possible, a portion of Gerota’s fascia is preserved over the tumor to allow for T3 staging as well as serving as a handle during excision of the tumor. The adrenal gland may be separated from the upper pole in sparing procedures or included en bloc for upper pole medial tumors. The 2010

European Association of Urology update on renal cell carcinoma guidelines does not recommend routine adrenalectomy unless preoperative imaging reveals an abnormal-appearing adrenal gland or operative findings include a grossly abnormal adrenal gland or adrenal nodule.

The role of lymph node dissection in renal cell carcinoma remains controversial [38, 39]. In patients with stage 1 renal cell carcinoma and clinically negative lymph nodes, lymph node dissection offers no survival benefit. Despite this, some continue to advocate lymph node dissection in patients undergoing radical nephrectomy and partial nephrectomy with larger T1b tumors because of the minimal added morbidity and chance for cure in patients with micrometastatic disease.

Hilar clamping

Depending on surgeon preference, various devices can be utilized for hilar clamping. A Satinsky clamp can be used for en bloc clamping or bulldog clamps for selective clamping. Significant variation in clamping technique exists. Gong et al., in a retrospective casecontrolled study, reported their experience of artery-only clamping in 25 patients compared to artery and vein clamping in 53 patients. Each group had similar blood loss. The artery and vein group had a significant increase in their postoperative creatinine, while the artery-only group had no significant change. Of the patients without preexisting kidney disease, there was no difference in the number of patients from each group developing renal insufficiency.

Renal hypothermia and administration of diuretics prior to hilar clamping have been employed to theoretically reduce cellular oxidative damage during renal ischemia and renal perfusion. A combination of mannitol and/or Lasix may be given prior to clamping. Methods of renal hypothermia including renal arterial perfusion with cold crystalloids, retrograde transurethral saline infusion, and kidney cooling with intraperitoneal ice slush are not routinely utilized given the technical challenges.

Early unclamping represents a significant technical improvement in reducing warm ischemic times. Utilizing this technique, the kidney is reperfused immediately after placement of the initial central running suture and prior to placement of mattress or bolster sutures. Our preference is to use a barbed unidirectional suture for this running anastomosis (V-Loc, Covidien, Mansfield, MA, USA). With the kidney unclamped, Vicryl (Ethicon, Somerville, NJ, USA) sutures are then placed on bleeding vessels until hemostasis is obtained. In their series of 100 patients, Nguyen et al. compared early unclamping to the standard technique and found similar intraoperative blood loss. The average clamp time in the early unclamping group was 13.9 min, which was about 6 min shorter than clamping times for open partial nephrectomy published in Gill’s comparison of open and laparoscopic partial nephrectomy. There was a trend towards fewer postoperative complications in the early unclamping group, although this was not statistically significant. The group hypothesized that early unclamping exposes bleeding that would otherwise not be exposed with clamped vessels. This allows for directed suture placement by the surgeon, which may translate into a reduced incidence of postoperative hemorrhage.

Guillonneau et al. published an initial retrospective comparison of clamping (n = 16) and non-clamping (n = 12) LPN. In the non-clamping group, tumor excision was performed using ultrasonic shears and bipolar electrocautery for hemostasis of the tumor bed. Oncologic control was not compromised as all patients had negative margins. Both groups had the same number of complications demonstrating the feasibility of non-clamping LPN. Rais-Bahrami and colleagues report their experience in off-clamp LPN in 126 patients. The off-clamp group had significantly more blood loss, but did not require more transfusions than the on-clamp cohort. At 6 months postoperatively, serum creatinine was found to be significantly less changed in the offclamp group suggesting the potential for improved renal functional outcomes. Performing off-clamp MIPN for more complex (central or hilar) tumors is typically not feasible given excessive blood loss and poor visualization.

Gill et al. described microdissection of tumor-specific arterial branches to eliminate global renal ischemia with the aid of preoperative 3-D CT imaging and color Doppler ultrasonography when needed. Clamping of select renal artery segment(s) supplying the tumor allows for partial nephrectomy while maintaining perfusion to the remaining kidney (Фиг. 14.3). Given its recent introduction, reproducibility of this technique and its benefits on renal functional outcomes are not yet clear.

Renal Cancer_ Contemporary Management-Springer New York (2013) 14.3

Фиг. 14.3. Selective clamping of one of three right-sided secondary renal artery branches (A1–A3) during roboticassisted laparoscopic partial nephrectomy. Intraoperative ultrasound with Doppler was performed demonstrating A2 as the renal artery branch supplying area of renal tumor (RT)

Резекция опухоли

Once the kidney is fully mobilized and access to the renal pedicle isolated, intraoperative ultrasound is utilized to confirm tumor location and depth, as well as the absence of other renal tumors. Using electrocautery, the tumor is demarcated circumferentially with ultrasound guidance. Tumor excision then proceeds with cold cutting with the goal of obtaining a small surrounding rim of normal renal tissue. The excised mass should be placed in a specimen retrieval bag to be removed prior to fascial closure. Data suggests that only minimal normal peritumor renal parenchyma is necessary for adequate local control. The reported rate of positive surgical margins after MIPN ranges from 0.7% to 5.7%. Data on the effect of positive surgical margin on local and distant disease recurrence appears to show minimal risk [52, 53], but long-term data on the effect on overall survival is lacking. The utility of frozen section in decreasing positive margins is also controversial with several studies reporting discrepancies with final pathology results [53–55]. Frozen section of random tissue samples from the tumor bed is low yield given the small sampling size. The surgeon’s gross inspection of the resected specimen seems to provide an accurate assessment of margin status. Frozen section may have a role in confirming suspicion that tumor was left in the tumor bed based on gross inspection of both the renal defect and the specimen.

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