Partial nephrectomy





Introduction


The incidence of renal cell carcinoma (RCC) has increased by 1.5% per year over the last decade and remains a primarily surgical disease. Nephron-sparing surgery for RCC was developed in the 1980s and is now the standard of care for small renal masses where technically feasible. This treatment paradigm has been driven by long-term oncologic and functional outcomes with proven equivalence to radical nephrectomy in addition to the established correlation of significant cardiovascular events to renal compromise.


Laparoscopic radical nephrectomy for the treatment of RCC was first reported in 1991, and the first laparoscopic partial nephrectomy by Clayman and colleagues quickly followed in 1992. The benefits of a minimally invasive approach include shorter hospital stays, less painful and more expeditious recoveries, and improved cosmesis. As minimally invasive surgery has evolved, the robotic approach with wristed instruments and improved three-dimensional visualization has largely replaced the laparoscopic partial nephrectomy.


This chapter highlights the technique for both laparoscopic and robotic minimally invasive partial nephrectomy with an emphasis on the transperitoneal approach and also discusses the retroperitoneal approach.


Indications and contraindications


Minimally invasive partial nephrectomy was historically indicated for only those patients with bilateral renal tumors, a renal mass in a solitary kidney, or a patient with significant preexisting chronic kidney disease. However, the indications for partial nephrectomy have expanded over the years to include even complex tumors in expert hands. Nephron-sparing surgery should now be attempted in any case where the procedure is technically feasible without fear of compromising outcomes. Laparoscopic or robotic partial nephrectomy should be attempted for all amenable tumors in patients with a hereditary syndrome (i.e., von Hippel-Lindau) or those at risk for end-stage renal disease. In select patients, such as those with an absolute indication for a nephron-sparing approach, a neoadjuvant trial of tyrosine kinase inhibitors can be used in an effort to downsize tumor burden to make the partial nephrectomy feasible as an alternative to radical nephrectomy and hemodialysis.


As experience with robotic partial nephrectomy has grown, the number of absolute contraindications to the approach has decreased. Contraindications to attempt a laparoscopic or robotic partial nephrectomy include a clinical stage above T3, significant renal vein or inferior venal caval thrombus in the presence of a normal contralateral kidney, significant prior abdominal surgery preventing a minimally invasive approach, and uncontrolled coagulopathy.


Transperitoneal partial nephrectomy


Patient preoperative evaluation and preparation


A detailed history and physical examination, along with a preoperative evaluation from an anesthesiologist, are required. Attention to prior surgical scars, body habitus, and any abnormalities that might limit patient positioning must be noted. Depending on the patient’s age and comorbidity profile, the patient should have an electrocardiogram and chest X-ray. Patients must undergo medical and cardiac clearance where appropriate. Laboratory evaluation including a urinalysis, urine culture, serum chemistry, clotting parameters, and a complete blood count should be available. In cases where blood loss is expected, a blood type and screen should also be performed. Anticoagulation should be held preoperatively, at the discretion of the surgeon.


Contrast-enhanced cross-sectional imaging should be completed and reviewed preoperatively when the patient’s renal function allows. The hilar vasculature must be studied, and identification of any aberrant vessels is critical, along with close inspection of the renal vein which may harbor tumor thrombus. In any case where a tumor thrombus is suspected, magnetic resonance imaging should be obtained to delineate the presence and extent of thrombus. Ipsilateral nephrolithiasis should be identified and treated prior to the partial nephrectomy if necessary to avoid postoperative ureteral obstruction. The appearance and health of the contralateral kidney must also be noted, along with the evaluation of the adrenal gland and neighboring retroperitoneal lymph nodes. Tumor details including location and proximity to surrounding structures, such as the hilum, are mandatory. For this detailed analysis, narrow 3–5 mm slices are preferred. While not widely available, three-dimensional rendered or printed models of the kidney illustrating the tumor details and vasculature can be useful in surgical planning. A staging chest film or chest computed tomography should also be completed, when clinically indicated.


A clear liquid diet is recommended starting the evening before surgery and stopped 2 hours prior to surgery, and a bowel preparation maybe utilized at the discretion of the surgeon. Our practice is to have the patient self-administer magnesium citrate the night prior to minimize colonic distension. Informed consent should be obtained and should review all risks associated with surgery, including bleeding, inability to cure, need for radical nephrectomy, urine leak and the possibility of conversion to an open procedure. In a patient with a solitary kidney or preexisting chronic kidney disease, the possible need for postoperative hemodialysis should be discussed.


Operating room configuration


Laparoscopy


The anesthesia team is always at the head of the bed and the scrub nurse and sterile instruments opposite the surgeon. The surgical assistant and surgeon are on the same side of the bed and face the patient’s abdomen for transperitoneal cases and the patient’s back or opposite one another for retroperitoneal cases. A monitor must be positioned such that it is easily visible for both individuals ( Fig. 17.1 ).




Fig. 17.1


A, Operating room configuration for laparoscopic transperitoneal partial nephrectomy. The patient is in a modified lateral position. Mayo, Mayo instrument table. B, Operating room configuration for laparoscopic retroperitoneal partial nephrectomy. The patient is in a full lateral position.




Robotic approach


For a robotic approach, the anesthesia team is again at the head of the bed. The surgeon and surgical assistant stand on opposite sides of the bed during port placement, but during robot docking and thereafter the surgical assistance stands or sits facing the patient’s abdomen for transperitoneal approach, and the patient’s back for a retroperitoneal approach. A monitor must be positioned such that it is easily visible for the bedside assistant. The robot is docked opposite the side of the surgical assistant when space allows, although with the da Vinci Xi robot (Intuitive Surgical, Sunnyvale, CA, USA), docking can be from either side and the boom rotated. The surgeon breaks scrub after the robot is docked to sit at the nearby console. The scrub technician and instrument table are generally at the foot of the bed near the surgical assistant so that the handing of instruments is unobstructed by the surgical robot ( Fig. 17.2 ).




Fig. 17.2


A, Operating room configuration for a robotic-assisted transperitoneal partial nephrectomy including the location of the surgical robot and surgeon console. B, Operating room configuration for robotic-assisted retroperitoneal partial nephrectomy. Note, in this case the robot is docked over the shoulder if using the Si, but more flexibility with docking is achieved with the Xi.


Patient positioning and preparation


Within 60 minutes of the incision, prophylactic antibiotics should be administered and sequential compression devices should be on and functioning. Data to support or refute pharmacologic prophylaxis for deep vein thrombosis (DVT) in the partial nephrectomy patient are lacking and thus are surgeon-dependent. After induction, an orogastric or nasogastric tube should be placed along with a Foley catheter. The team should verify that all required equipment is in the room and functioning. Robotic instruments for this procedure generally include fenestrated bipolar forceps, monopolar scissors, ProGrasp forceps and two needle drivers (Intuitive Surgical, Sunnyvale, CA, USA). The surgeon must also verify the availability of his or her preferred locking clips and sutures, ultrasound probes, and bulldog clamps. Especially in complex cases, an open surgical instrument set should also be available in the case of a need for conversion.


The patient is then anesthetized and placed in a modified flank position with the bed in a mild to moderate degree of flex to provide room between the costal margin and the anterior superior iliac spine. The patient is secured to the bed with silk tape or Velcro straps at the chest, hip and knee, and all pressure points are padded with care. Joints are slightly flexed where possible and attention must be given avoid hyperextension of these joints during the procedure. The bottom leg is bent, and pillows are used to separate the legs in an ergonomic position. The top leg is generally straight, and the legs are then also secured to the bed. The ipsilateral arm can either be positioned at the patient’s side with foam padding or can be placed over the chest usually at the nipple line (the latter is preferred if using all four robotic arms) but varies by surgeon preference. The contralateral arm is generally placed out on an arm board, and an axillary roll is utilized as needed. The bed must be rotated laterally and tested in a position 10–20 degrees from level in either direction to be sure that the patient’s position and head are secure before the patient is prepped and draped. A forced air patient warming device can then be attached.


Retroperitoneal cases require the patient to be placed in a full lateral position with the arms and legs positioned and padded as in transperitoneal cases. In addition, there should be ample space to allow for the most lateral instrument to have full range of motion, free from the straps and rolls used to secure the patient, as well as the drapes.


Abdominal access


A Veress needle is used to insufflate the abdomen in uncomplicated cases. The Veress needle is often placed at the umbilicus when prior abdominal surgery is not a concern. Penetrating towel clamps can be used to lift the patient’s abdominal wall away from underlying bowel. The proper placement of the Veress needle is verified first by aspiration and then by a saline drop test using a 10-cc sterile syringe; saline should immediately and freely flow into the peritoneum if the needle is in the correct place. The insufflator is then connected, and the initial pressures should be low accompanied by high flow and rise gradually to 12–15 mm Hg as a maximum. Veress needle placement in the right or left upper quadrants just off the costal margin is also acceptable. Attempts at needle placement should always avoid areas with prior scarring.


Once insufflated, a skin incision is made, and a visual port is used to enter the abdomen under direct vision as the port travels through the layers of the abdominal wall. As an alternative, the Hassan cut down technique can be employed to place the first port under direct visualization. Once the camera port is placed, the surgeon should check the prior Veress needle insertion, where applicable, and verify that there is no underlying injury. The patient should then be rotated toward the surgeon to allow the bowel to fall medially.


Trocar placement


Laparoscopy


For most cases of laparoscopic partial nephrectomy, three trocars are used. For the transperitoneal approach, a 10-mm camera trocar is generally placed near the umbilicus (but may be moved lateral and cranial in the obese patient) and the remaining two ports are triangulated and placed thereafter, with the first trocar just lateral to the rectus muscle in the midclavicular line. The second trocar, which is generally a 5-mm port, can be placed midline cephalad to the camera port, about halfway between the umbilicus and the xyphoid. An additional midline trocar can be placed cephalad to the second trocar, just below the xiphoid as a liver retractor for right-sided tumors ( Fig. 17.3 ). Some surgeons prefer to place an additional 10/12-mm port more inferiorly to allow for placement of a Satinsky clamp if laparoscopic bulldogs are not being used.




Fig. 17.3


A, Trocar placement for left-sided transperitoneal laparoscopic nephron-sparing surgery. B, Trocar placement for right-sided transperitoneal laparoscopic nephron-sparing surgery. C, In the obese patient, the entire trocar configuration is shifted so that what would have been the umbilical trocar is in line with the umbilicus but placed lateral to the rectus muscle.


For the retroperitoneal approach, an incision is made just above the anterior superior iliac spine (historically, the 12th rib was used as the landmark, but given the variation in anatomy, we have found this to be less helpful), and the retroperitoneal space can be bluntly probed with the surgeon’s finger. The camera is placed through a 10-mm balloon trocar. The space may be developed by blunt dissection with the camera or a space-making balloon. If a balloon is used, care must be taken to ensure it is positioned in the correct plane prior to dilation, otherwise the surgery may be greatly complicated ( Fig. 17.4 ). Often the ureter and gonadal vessels can be seen during balloon inflation. Ultimately, the psoas muscle should be visualized inferiorly (which is the primary working landmark), the Gerota fascia cephalad, and peritoneum anteriorly. A trocar with an inflatable cuff is preferred as this can be pulled to the skin to prevent carbon dioxide leakage. Once a large enough space is created using blunt dissection or balloon dilation, a 5-mm trocar is placed laterally. A Kittner dissector may be introduced through this trocar to sweep the peritoneum medially to make room for the additional medial trocar and assistant port ( Fig. 17.5 ).




Fig. 17.4


A, In the retroperitoneal approach, an incision is made off about one finger breadth above the ASIS, large enough to allow placement of the index finger into the retroperitoneal space. The surgeon’s finger is used to develop a space above the psoas muscle, posterior to the kidney. B, The camera or a SpaceMaker balloon (Medtronic, Minneapolis, MN, USA) is used to devolve the plan anterior to the psoas fascia but posterior to the kidney to create the working space.



Fig. 17.5


Trocar placement for retroperitoneal laparoscopic nephron-sparing surgery.


Robotic approach ( )


For an intraperitoneal robotic approach, the camera trocar is placed just lateral and cephalad to the umbilicus, or at the umbilicus, depending on patient habitus, using a visual obturator as above. The use of two versus three robotic arms is surgeon-dependent. For a three-arm configuration, one port is placed under direct vision two fingerbreadths off of the iliac crest, inferior and lateral to the camera port. The second robotic arm is placed along the mid-clavicular line just below the costal margin. A 3- or 5-mm port can be placed subxiphoid for liver retraction in the case of a right-sided tumor. In the three-robot arm approach, two assistant ports are utilized, and at least one is 12 mm in size to allow for the laparoscopic bulldogs to be transferred. The first assistant port is placed between the camera and lower robotic arm port in the mid-clavicular line. The second assistant port is placed between the camera and the upper robotic arm port, a handbreadth cephalad and slightly medial to the camera. For the four–robotic arm approach, a similar placement of ports can take place but with a slight cephalad shift to allow room for an additional robotic arm caudal to the camera port ( Fig. 17.6 ). All ports should have approximately one handbreadth between them, which is generally made possible with pneumoperitoneum.


Aug 8, 2022 | Posted by in UROLOGY | Comments Off on Partial nephrectomy
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