Clinical Essentials: Interpretation of Guidelines for Robot-Assisted Radical Prostatectomy via Transvesical Approach

Robot-assisted radical prostatectomy (RARP) was first reported by Abbou in France in 2000
.

The prognosis of this procedure is no less than that of open surgery and laparoscopic surgery in early tumor control, urinary continence and erectile function recovery after prostate cancer surgery
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At present, the relatively popular and recognized nerve-sparing RARP surgery takes the bladder as a reference.
According to the initial approach, it can be divided into two categories: anterior approach and posterior approach: one is to find the separation plane from the front of the bladder, that is, through the retropubic space.
The VIP (Vattikuti institute prostatectomy) procedure, represented by the anterior approach, has the advantages of large operating space, obvious anatomical landmarks, and convenient urethra-bladder neck anastomosis.
However, it is necessary to better preserve and protect the neurovascular bundle (NVB).
Long learning curve and high technical requirements
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The other is to look for the separation plane from the back of the bladder, that is, the retropubic space preservation or the transvesicorectal depression RARP represented by the Bocciardi procedure.
Compared with the anterior approach, there are fewer surgical steps, but the intraoperative visual field is poorly exposed.
, the learning curve is longer, and the proportion of complete urinary continence within 7 days of catheter removal can be as high as 90%; among the patients who could have normal sexual life before surgery, >40% of the patients had their first sexual life 1 month after surgery.
>70% of patients resumed sexual activity within 1 year after surgery
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With the continuous development of robotic minimally invasive surgical technology, and in order to better achieve the surgical goal of "three consecutive victories", the surgical approach of RARP has also been innovated and developed to varying degrees
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Among them, the transvesical approach is an antegrade approach that separates the prostate and surrounding tissue structures through the bladder cavity.
Studies have confirmed that the transvesical approach to RARP is one of the options for the treatment of localized low-risk prostate cancer.
The results of immediate postoperative urinary continence between the approach and the posterior approach RARP were similar, and both were superior to the anterior approach
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In order to better standardize and popularize transvesical approach RARP (TvRARP) and single-port extraperitoneal transvesical RARP (SETvRARP), many medical centers have invited people with rich experience in robotic surgery on the basis of summarizing their units to carry out such operations.
This consensus was formulated by domestic experts from experts and related literatures at home and abroad for the selection of patients through the transvesical approach, the key points of intraoperative operations, and the prevention and treatment of surgical complications
.

At present, for patients with benign prostatic hyperplasia with a prostate volume of more than 100ml, the EAU guideline has included simple prostatectomy through the bladder robot as one of the optional surgical procedures.
The surgical methods and steps have been standardized, suggesting that transvesical prostate dissection has Feasibility
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The surgical operation of the transvesical approach is limited to the pelvic space around the prostate, and the damage to other surrounding tissues is less.
The tumor control effect is ideal
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Theoretical basis and key technical design 1.
In addition to the neurovascular bundles that run on the posterolateral side of the prostate, the neurovascular network (Veil of Aphrodite, Veil of Aphrodite) attached to the anterior surface of the prostate is also accessible to the patient.
Recovery of urinary continence and erectile function after surgery is of great significance
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The retropubic space preservation or transvesicorectal depression RARP represented by the Bocciardi procedure (posterior approach) starts from the back of the bladder without nerve distribution to find the separation plane.
The surgical scope is relatively small and the steps are less, and the urinary catheter is removed.
The proportion of complete urinary continence within 7 days is as high as 90%
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The ideal degree of immediate urinary continence recovery after catheter removal 1 week after surgery has also been further validated in randomized controlled clinical trials
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The transvesical approach is used to perform RARP.
After incising the bladder, exposing the internal orifice of the urethra and bilateral ureteral openings, and circularly incising the mucosa along the internal orifice of the urethra, the posterior approach surgical separation technique is used to separate the vas deferens behind the prostate.
and seminal vesicles, and then find the correct extrafascial, interfascial, and intrafascial planes on the posterior surface of the prostate without nerve distribution, and use this plane as a reference to continue to perform follow-up on the lateral side of the prostate and the vascular pedicle located on the posterolateral side of the prostate.
Isolation of neurovascular bundles (NVBs)
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2.
The separation of prostate vascular pedicle and neurovascular bundle The prostate vascular pedicle and the neurovascular bundle, which are important for postoperative urinary continence and erectile function, are located at 4-5 o'clock (right) and 7-8 o'clock (left) on the posterolateral side of the prostate
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When performing RARP through the bladder approach, when exposing these two key structures, the lateral approach technique can be used for reference.
When separating the right side, the separation plane between the prostate capsule and the fascia around the prostate is first constructed at 3 points
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After the plane is fully constructed, first use Hem-o-Lok to close the prostate capsule to clamp and cut off the prostate vascular pedicle at 4-5 points with a cold knife.
Between the visceral layers of the membrane (intrafascial or interfascial layer), anterograde blunt dissection of the NVB running on the posterolateral side is performed to achieve the preservation of the NVB trunk
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The left NVB was dissected and separated in the same way
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3.
Vesicourethral anastomosis The operation habit of vesicourethral anastomosis through the bladder approach is almost exactly the same as that of the anterior approach
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The Bocciardi procedure (posterior approach) performs vesicourethral anastomosis behind the bladder, which is different from the anterior approach familiar to most urologists
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Prostate cancer with limited indications and low recurrence risk was selected for the patient, and no extracapsular invasion was found in preoperative imaging examination; tPSA<20ng/mL; Gleason score≤7; clinical stage cT1-T2cN0M0; prostate volume <80ml; patient life expectancy >10 years
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Contraindications Non-localized prostate cancer (≥T3); tPSA>20ng/ml; Gleason score>7; life expectancy <10 years; uncorrected coagulation dysfunction; patients with severe underlying diseases such as severe pulmonary insufficiency intolerance The patients who underwent surgery and the patients or their families did not undergo radical prostatectomy
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Preoperative preparation of patients Preoperative routine comprehensive and systematic physical examination, laboratory tests and imaging examinations for patients.
Physical examinations and laboratory tests mainly include digital rectal examination, cardiopulmonary function test, electrocardiogram, blood routine, blood biochemistry, coagulation Function, blood type, etc.
; imaging examinations mainly include prostate MRI, bone scan, chest CT examination, etc.
to evaluate the patient's basic state and tumor clinical staging
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A good nutritional status before surgery can enhance the ability to resist risks such as infection, and a normal diet can be maintained before surgery
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According to the requirements of general anesthesia, the patients were fasted for 6 hours and water for 4 hours before the operation.
The night before the operation, laxatives were taken orally to prepare the gastrointestinal tract to empty the residues in the gastrointestinal tract
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Preoperative routine prophylactic use of broad-spectrum antibiotics
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Operating room preparation, patient position and cannula position 1.
TvRARP/SETvRARP patient position The patient is under general anesthesia with endotracheal intubation
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For TvRARP, the lithotomy position was slightly lower than the head (about 15°), and the lower extremities were separated by 80°~90°.
Since the lens was located in the bladder most of the time during the operation, it was not easily disturbed by the abdominal contents
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In SETvRARP, the lens is always located in the bladder and is completely uninterrupted by the contents of the abdominal cavity.
Therefore, it can be performed in the same way as retropubic extraperitoneal prostatectomy, and the operation can be performed in a mild head-down position or a horizontal supine position (Figure 1)
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Routine preoperative disinfection, laying sheets, inserting a 14F catheter, and fixing the balloon with an appropriate amount of normal saline
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2.
TvRARP/SETvRARP tube placement 2.
1TvRARP tube placement The lens tube poking hole (C) is located 1cm above or below the umbilicus, and the 8mm R1 and R2 manipulator tube poking holes are located in the lens tube poking holes respectively On both sides, the 8mm R3 manipulator casing punch hole is located outside the R2 manipulator casing punch hole, and the 12mm assistant casing punch hole (A1) is located outside the 1 manipulator casing punch hole, as shown in Figure 2A
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2.
2 Placement of the SETvRARP cannula to set up the single-port PORT: after emptying the bladder, inject 400~600ml of normal saline into the bladder through the urinary catheter, so that the bladder is in a fully filled state, at least 2 fingers above the pubic symphysis.
Touch the bladder horizontally; make a longitudinal or transverse incision about 5cm long below the umbilicus, which is located at about the midpoint of the umbilicus and the pubic symphysis, and can be moved up or down appropriately according to the patient’s body size; The white line bluntly separates the rectus abdominis, anterior bladder fat, and bladder wall until the bladder mucosa layer is exposed; 6-8 interrupted sutures are used to fix the incision edge of the bladder wall to the skin; The 8~12mm channel is located on both sides (for placing the 8mm cannula of the Da Vinci Xi surgical robot system and the left and right hand manipulation instruments), and the third 8~12mm channel is located on the caudal side (for placing the da Vinci Xi surgical robot 8mm cannula and lens of the system), and another 5–12mm channel on the cephalic side (used as an assistant hole for the use of the 5mm aspirator and the 10mm Hem-o-Lok clip applier), as shown in Figure 2B
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TvRARP/SETvRARP pneumoperitoneal pressure setting 1.
TvRARP pneumoperitoneum pressure is the same as other transabdominal surgery: 12~15mmHg, high pneumoperitoneum pressure may lead to excessive carbon dioxide accumulation in the body, causing harmful blood gas changes, especially in elderly patients who need Special attention; pneumoperitoneal pressure can be appropriately reduced to 5~10mmHg when hemostasis is performed on the prostate fossa to find potential bleeding points
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2.
Units with SETvRARP conditions for intravesical air pressure can choose an automatic constant pressure pump device to keep the operating environment at constant pressure and a clear field of vision; when hemostasis in the prostate fossa, the pneumoperitoneum pressure can be appropriately reduced to 5-10mmHg to detect potential Bleeding point; when performing vesicourethral anastomosis, it is necessary to reduce the air pressure in the bladder to 5~10mmHg in order to achieve tension-free anastomosis
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Prostate cancer patients who underwent TvRARP and SETvRARP for lymph node dissection were selected for localized and low-risk patients due to their indications, and pelvic lymph node dissection was often not required
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Current guidelines recommend against extended pelvic lymphadenectomy for low-risk patients, and not recommended for limited pelvic lymphadenectomy
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In addition, intraoperative frozen pathological examination is not recommended to determine whether there is lymph node metastasis
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If lymph node dissection is required for intraoperative assessment, TvRARP can be performed with pelvic lymph node dissection before or after radical prostatectomy; SETvRARP cannot be performed concurrently with pelvic lymph node dissection unless re-abdominal cannula placement and anchoring are performed
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The surgical steps and technical points of TvRARP/SETvRARP are shown in Figures 3 and 4
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TvRARP/SETvRARP cystotomy direction TvRARP/SETvRARP surgery should be longitudinal incision of the bladder
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Whether TvRARP uses suspension sutures to make a longitudinal incision on the upper bladder wall, the longitudinal incision can be opened into a diamond shape by indwelling indwelling sutures on both sides of the incision edge and traction to both sides, so as to obtain sufficient intravesical structure.
exposed
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If the surgeon is skilled, no sutures can be considered
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Needles and sutures for TvRARP/SETvRARP vesicourethral anastomosis According to reports, 2 reversely running RB-1 needles with 3-0 barbed sutures can be used to complete vesicourethral anastomosis, and the final knot is tied at the bladder-urethral anastomosis.
outside to avoid irritation of the triangular area of ​​the intravesical line knot (which may lead to postoperative dysuria) and stone formation
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Other needle and thread options include 1 3-0 barbed thread and 1 reverse run 3-0 PDS thread, a single 3-0 barb thread, or a single 3-0 PDS thread,
etc.

The TvRARP/SETvRARP bladder is sutured in two layers to close the bladder mucosa/superficial muscle layer and deep muscle layer/serosa, respectively
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Optional sutures include 3-0 barbed thread, 3-0 plain Vicryl thread, 3-0 PDS thread,
etc.

The suture is continuous suture
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If pelvic lymph node dissection is not performed at the same time for postoperative drainage of TvRARP/SETvRARP, the pelvic drainage tube outside the bladder may not be indwelled, but only the indwelling catheter can be used to drain the bladder
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Some scholars have also proposed that the suprapubic cystostomy tube is used to replace the urinary catheter to drain the bladder, and the postoperative discomfort of patients is lower.
Prevention and treatment of major surgical complications, ureteral orifice and ureteral injury are less likely to occur during TvRARP/SETvRARP surgery.
See, because the position of the ureteral opening can be observed under direct vision in the bladder
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If the surgeon considers that there is a risk of ureteral injury during the separation of the prostate, retrograde indwelling ureteral stents can be considered during the operation
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Posterior infiltration of rectal injury tumor, transrectal prostate biopsy, pelvic radiotherapy, etc.
can lead to unclear anatomical plane between prostate and rectum.
Preoperative bowel preparation can be considered for patients with high risk of rectal injury assessed before operation; intraoperative use can be considered A rectal probe aids in positioning, and the surgeon and assistant collaborate to fully expose the plane of separation between the posterior surface of the prostate and the anterior wall of the rectum
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In the vast majority of cases, one-stage repair, indwelling anal canal, and short-term postoperative parenteral nutrition can be performed
;
Selecting early, limited, low-risk cases and standardizing surgical procedures can often avoid this complication
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Major hemorrhage in radical prostatectomy is mainly from the damage of the doral vascular complex (DVC) and the vascular pedicle of the prostate side
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For radical prostatectomy, if the operation is performed in accordance with the aforementioned requirements, accidental injury to the DVC and the vascular pedicle on the prostatic side can often be avoided
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Anastomotic leakage is often caused by excessive anastomotic tension and poor coaptation during vesicourethral anastomosis
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When performing vesicourethral anastomosis, the tension should be minimized and the involution should be good
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When urinary leakage and extravasation occur after surgery, the catheter indwelling time should be appropriately extended
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The occurrence of urethral stricture is usually caused by too small vesicourethral anastomosis or urine leakage, and urethral cystography can be used to assist in diagnosis and treatment
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Urinary tract dilation or transurethral resection can be considered when it does occur
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Urinary incontinence TvRARP/SETvRARP can maximize the protection of urinary continence muscles and other structures, so as to obtain a better immediate postoperative urinary continence advantage
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Erectile dysfunction TvRARP/SETvRARP can usually preserve the erectile neurovascular bundle NVB, so that the erectile function can be better protected and restored after surgery
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During the operation, cold knife should be used as much as possible to avoid thermal damage to the erectile nerve
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Robotic transvesical radical prostatectomy with positive margins is usually performed in patients with early-stage, limited cancer, and low-risk patients.
If the indications are appropriate and the surgical operation is rigorous and standardized, the positive rate of margins should not be high
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However, due to the certain learning curve of transvesical surgery, positive margins may occur in first-timers
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For patients with positive margins, adjuvant endocrine therapy or adjuvant radiotherapy can be selected after surgery
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Precautions for surgery TvRARP/SETvRARP is recommended to select those with smaller prostate volume (<50g) due to its relatively small surgical area in the initial stage of the operation.
In patients with localized prostate cancer, better tumor control can be guaranteed
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Patients are encouraged to adopt the concept and measures of enhanced recovery after surgery.
Under the premise of no special discomfort or other systemic conditions, they can try to get out of bed under close supervision for 6-12 hours after surgery as appropriate; gradually return to normal diet after anal exhaust
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SETvRARP is an extraperitoneal route, which has almost no interference with the abdominal organs, and can be properly restored to normal diet earlier
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Urinary catheters were routinely removed 7 days after surgery
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The postoperative follow-up plan refers to the latest guidelines for follow-up management of patients after RARP
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References: [1] Wang Gongxian, Zhou Xiaochen.
Chinese expert consensus on robotic-assisted radical prostatectomy via transvesical approach (2021 edition) [J].
Journal of Robotic Surgery (Chinese and English), 2022,3(02):149- 160.
Revision: XY Typesetting: LR Execution: LR