Open Radical Prostatectomy

Radical retropubic prostatectomy: surgical anatomy

• See Prostate Anatomy Chapter Notes
• During radical perineal prostatectomy, the endopelvic and anterior pelvic fasciae are reflected off the prostate in an effort to avoid injury to the dorsal vein of the penis and Santorini plexus. Therefore, the dorsal vein complex is not divided during perineal prostatectomy because the dissection occurs beneath the endopelvic fascia and anterior pelvic fascia.
• In performing radical retropubic prostatectomy, the prostate is approached from outside these fascial investments. For this reason, the dorsal vein complex must be ligated and the lateral pelvic fascia must be divided
• Radical prostatectomy may compromise arterial supply to the penis.
  • Although the major arterial supply to the corpora cavernosa is derived from the internal pudendal artery. pudendal arteries can arise from abberant branches the obturator (most commonly), inferior vesical, and superior vesical arteries. These aberrant branches travel along the lower part of the bladder and anterolateral surface of the prostate and are typically divided during radical prostatectomy.
• Pelvic plexus
  • The branches of the inferior vesical artery and vein that supply the bladder and prostate perforate the pelvic plexus.
    • Division of the so-called lateral pedicles of the bladder and prostate proximally/in its midportion not only interrupts the vessels but also transects the nerve supply to the prostate, urethra, and corpora cavernosa with attendant postoperative impotence. Ligation is best carried out near the bladder to avoid nerve damage.
  • The cavernous nerve branches join the capsular arteries and veins in a spraylike distribution to form the NVB 20 to 30 mm distal to the junction of the bladder and prostate. The NVBs are located between the prostatic and the endopelvic/levator fascia.
• Striated urethral sphincter
  • In the adult, the fibers at the apex of the prostate are horseshoe shaped and form a tubular, striated sphincter surrounding the membranous urethra. Near the apex of the prostate, the edges fuse in the midline posteriorly
  • Contains fatigue-resistant, slow-twitch fibers that are responsible for passive urinary control.
  • The pudendal nerve provides the major nerve supply to the striated sphincter and levator ani.

Surgical technique of open radical retropubic prostatectomy

• Timing
  • Deferred for 6-8 weeks after needle biopsy of the prostate and 12 weeks after transurethral resection of the prostate
• The anesthesiologist is encouraged to maintain relative hypotension with systolic blood pressure of ≤ 100 mm Hg and to limit the replacement of crystalloid to 1500 mL until the prostate is removed
• Summary of steps:
  • See BJUI Surgical Atlas and Video
  • Position: supine; table can be flexed in obese men to increase the distance between the umbilicus and pubis.
  • Preparation: the skin is prepared and draped in the usual way. A No. 16 Silastic Foley catheter is passed into the bladder, inflated with 20 mL of saline, and connected to sterile, closed, continuous drainage. The use of a 16-Fr catheter facilitates placement of sutures in the mucosa of the urethra.
  • Incision: An extraperitoneal, lower abdominal incision is made extending from the pubis toward the umbilicus. The anterior fascia is incised down to the pubis, the rectus muscles are separated in the midline, and the transversalis fascia is opened sharply to expose the Retzius space.
  • Laterally, the peritoneum is mobilized off the external iliac vessels to the bifurcation of the common iliac artery. Care is taken to preserve the soft tissue covering the external iliac artery that contains the lymphatics draining the lower extremity. Interruption of these lymphatics may lead to lower extremity edema and lymphocele formation. This maneuver is accomplished without dividing the vas deferens.
  • Next, a self-retaining Balfour retractor is placed. Exposure for the lymph node dissection is facilitated by placement of a narrow, malleable blade attached to the Balfour retractor beneath the mobilized vas deferens to displace the peritoneum superiorly and a deep Deaver retractor to retract the bladder medially
  • Pelvic lymph node dissection is performed before the radical prostatectomy.
    • Internal iliac lymph nodes (hypogastric) have the highest risk of being positive for metastasis.§
    • The lymphatics overlying the external iliac artery are preserved; the dissection proceeds beneath the external iliac vein
    • Limits of dissection:
      • Inferiorly: femoral canal or circumflex vein
      • Superiorly: ureter/bifurcation of the common iliac artery
      • Medially: bladder
      • Laterally to the pelvic side wall
      • Posteriorly: obturator nerve (internal iliac vein in extended PLND)
        • The obturator lymph nodes are removed with care to avoid injury to the obturator nerve.
        • The obturator artery and vein are skeletonized but usually are left undisturbed and not ligated unless excessive bleeding occurs.
  • If the patient has a well-differentiated to moderately well-differentiated tumor (Gleason grade < 8) and the lymph nodes are normal to palpation, frozen-section analysis is not performed
  • To expose the anterior surface of the prostate, it is necessary to displace the peritoneum superiorly. A malleable blade is used to retract the peritoneum superiorly and to gently displace the bladder posteriorly.
  • The fibroadipose tissue covering the prostate is carefully dissected away to expose the pelvic fascia, puboprostatic ligaments, and superficial branch of the dorsal vein.
  • The endopelvic fascia is entered where it reflects over the pelvic sidewall, well away from its attachments to the bladder and prostate. The point of incision is where the fascia is transparent, revealing the underlying levator ani musculature. Incision more medially can lead to entry into the lateral venous plexus of Santorini running alongside the prostate, resulting in persistent venous bleeding. Beneath this venous complex lie the prostatic arteries and the branches of the pelvic plexus that course toward the prostate, urethra, and corpora cavernosa.
  • The incision in the endopelvic fascia is then extended in an anteromedial direction toward the puboprostatic ligaments. This allows the surgeon to palpate the lateral surface of the prostate. At this point, small arterial and venous branches from the pudendal vessels are encountered that perforate the pelvic musculature to supply the prostate. These vessels should be ligated with clips to avoid coagulation injury to the pudendal artery and nerve, which are located just deep to this muscle as they travel along the pubic ramus.
  • The fibrofatty tissue covering the superficial branch of the dorsal vein and puboprostatic ligaments is gently teased away to prepare for division of the puboprostatic ligaments without injury to the superficial branch of the dorsal vein. After the superficial branch has been dissected away from the medial edge of the ligaments, it is coagulated and divided. After all fibrofatty tissue has been removed, a sponge stick is used to gently displace the prostate posteriorly and scissors are used to divide each ligament superficially, just enough to expose the juncture between the apex of the prostate and the anterior surface of the dorsal vein complex at the point where it will be divided. The pubourethral component of the complex should be spared to preserve the anterior fixation of the striated urethral sphincter to the pubis
  • The goal is to divide the dorsal vein complex with minimal blood loss while avoiding damage to the striated sphincter and inadvertent entry into the anterior apex of the prostate. With use of the sponge stick to push the prostate posteriorly, a 3-0 Monocryl suture is passed through to ligate the dorsal vein complex just distal to the apex of the prostate
  • The apical dissection is the most complex and important step in the operation. The striated sphincter and the surrounding dorsa vein must be divided with care to avoid inadvertent incision into the apex of the prostate, the most common site for positive margins.
    • Most patients with positive surgical margins are cured by the radical prostatectomy
  • With the application of gentle downward pressure on the anterior surface of the prostate with a sponge stick, Metzenbaum scissors or a No. 15 blade is used to divide the dorsal vein complex
    • See Figure for representation of DVC in relationship to other surrounding veins
    • When the dorsal vein complex is divided anteriorly, the striated sphincter complex is the most common major structure that can be damaged, increasing the risk of incontinence
  • To avoid back-bleeding from the anterior surface of the prostate, the edges of the proximal dorsal vein complex on the anterior surface of the prostate are sewn in the shape of a V with a running 2-0 absorbable suture. If one tries to pull these edges together in the midline, the neurovascular bundles can be advanced too far anteriorly on the prostate.
  • With scissors, the anterior two thirds of the urethra is divided with care to avoid damage to the Foley catheter. This provides excellent exposure for placement of six sutures in the distal urethral segment at the 1-, 3-, 5, 7-, 9- and 11-o’clock positions. With 3-0 Monocryl on a 5 8 circle tapered needle, the needle should incorporate just the urethral mucosa and submucosa but not the smooth muscle.
  • The posterior band of the urethra is now divided to expose the posterior portion of the striated urethral sphincter complex
  • To divide the posterior portion of the sphincter safely, a right-angled clamp is passed immediately beneath the left edge of this complex. The clamp should pass midway between the apex of the prostate and the urethra
  • The neurovascular bundle is outside the prostate between the prostatic and endopelvic/levator fascia. If nerve sparing is performed correctly, the prostatic fascia must remain on the prostate. This is called an interfascial dissection.  
    • In performing nerve-sparing surgery, the neurovascular bundles are identified at the apex of the prostate, and the bundles are dissected free of the posterolateral surface of the prostate gland. When the neurovascular bundle is released, there should be no upward traction on the prostate. Rather, the prostate should be rolled from side to side.
    • Preoperatively, no definite decision is made as to when and where to excise the NVB. Consideration is given to the status of sexual function, but in impotent patients, there is evidence that the bundles provide both somatic and autonomic innervation to the continence mechanism and that patients who undergo excision of both NVBs have more incontinence than do patients in whom the NVBs are preserved. However, no final decision is made until the time of surgery.
    • When the endopelvic fascia is opened, if induration is palpable, the NVB on that side is widely excised. If there is no induration but the NVB appears to be fixed to the prostate at the time it is being released, it is also excised. However, the final decision about preservation or wide excision of the NVB does not need to be made until the prostate is removed. If there appears to be inadequate tissue over the posterolateral surface after the prostate has been removed, the NVB can then be widely excised.
    • The advantages of releasing the levator fascia higher at the apex is to speed up recovery of sexual function by reducing traction on the branches of the nerves to the cavernous bodies and striated sphincter and/or avoiding inadvertent transection of the small branches that travel anteriorly. However, because there is less soft tissue at the apex, the risk of positive margins may be increased.
  • The vascular branches to the NVBs are best controlled by small hemoclips placed parallel to the bundle. Thermal energy of any form (unipolar, bipolar, or harmonic scissors) should never be used on the NVB or its branches
  • Once the NVBs have been either preserved at the apex or widely excised and the prostate has been mobilized to the level of the seminal vesicles, the catheter is replaced and, with light upward traction on the catheter, the attachment between the rectum and Denonvilliers fascia is divided in the midline posteriorly
  • After the plane between the rectum and prostate in the midline has been developed, it is possible to release the neurovascular bundle from the prostate, beginning at the apex and moving toward the base, by using the sponge stick to roll the prostate over on its side. Beginning on the rectal surface, the bundle is released from the prostate by spreading a right angle gently. With use of this plane, Denonvilliers fascia and the prostatic fascia remain on the prostate; only the residual fragments of the levator fascia are released from the prostate laterally.
    • The surgeon does not have to make the decision about whether to excise or preserve the neurovascular bundle until the prostate is removed, and, if there is not enough soft tissue covering the prostate, one can excise the neurovascular bundle then.
  • Before the lateral pedicles are divided, the posterior branch of the NVB that must be identified and released. At this point the lateral pedicle can be divided safely on the lateral surface of the seminal vesicles without injury to the NVB
  • The prostate has now been mobilized almost completely. The bladder neck is incised anteriorly at the prostatovesicular junction. The incision is carried down to the mucosa, the mucosa is incised, the Foley balloon is deflated, and the two ends of the catheter are clamped together to provide traction.
  • After the posterior bladder wall is divided, the bladder neck is retracted with an Allis clamp, and the vasa deferentia are ligated with hemoclips and divided. The seminal vesicles are dissected free from surrounding structures. Recall that the pelvic plexus is located on the lateral surface of the seminal vesicles.
    • Sparing of the seminal vesicles has not improved incontinence, potency, or margin status, and there have been no reported cases of pelvic abscess.
    • Sparing of the bladder neck has not improved incontinence, potency, margin status, or stricture rates.
  • During placement of the anterior vesicourethral anastomotic sutures, a red rubber catheter is placed transurethrally and used to identify the membranous urethral stump and also provide traction on the urethra to assist in placement of the sutures. The red rubber catheter is then removed, and the indwelling Foley catheter is then placed retrograde into the bladder. Simple interrupted sutures are placed for the anastomosis.
  • A tennis-racquet technique with a running suture or interrupted 2-0 absorbable sutures to approximate full-thickness muscularis and mucosa is used for bladder neck reconstruction if necessary.

Radical perineal prostatectomy

• Advantages compared to radical retropubic prostatectomy
  1. Shorter hospital stays and lower costs
  2. Blood loss is significantly lower than with the retropubic approach.
  • • The dorsal venous complex is usually not encountered, resulting in relatively lower blood loss when compared with the retropubic approach.
    • Transfusion rates are generally around 5%.
    • A blood type and antibody screen are performed in the days or hours before surgery, but a crossmatch is generally unnecessary.
• Disadvantages
  1. Inability to perform lymph node dissection
     • In the 1970s, the procedure fell out of favor because the importance of pelvic lymphadenectomy was understood for the purposes of staging. However, with the advent of nomograms, surgeons could accurately predict the chances of lymph node involvement, obviating the need for staging lymphadenectomy.
     • Concomitant radical perineal prostatectomy and laparoscopic lymph node dissection results in little increased morbidity and remains cost effective when compared with radical retropubic prostatectomy.
  2. Potential post-operative sensory neurapraxia of the lower extremity due to positioning
  • • Occur in approximately 2% of cases, significantly more often than with retropubic prostatectomy.
    • Transient in nature, true motor defecits are rare
• Similarities
  • Pathologic outcomes are not significantly different for either procedure
  • A nerve-sparing technique can be accomplished.
• Indications
  • Patients with prior renal transplantation or morbid obesity are often better candidates for a perineal approach than for the retropubic approach.
• Contraindications
  • Ankylosis of the hips or spine
    • Procedure necessitates either an exaggerated lithotomy or a modified exaggerated lithotomy position
    • A history of degenerative disk disease is not a contraindication to surgery.
• Procedure
  • Exposure of the urethra is facilitated by the Lowsley retractor
    • Traction on the Lowsley tractor during division of the rectourethralis muscle tents the rectum upward and increases the likelihood of injury during radical perineal prostatectomy. Traction should not be placed until after the rectourethralis muscle is divided.
      • If a rectal injury occurs, a fistula may ensue.
        • Incidence of rectal injury: 1-5%.
        • When the injury is recognized and repaired at the time of occurrence, the operation can continue without a problem

Postoperative Management

• Patients are offered a clear liquid diet on the evening of surgery and a regular low-fat diet the next day.
• A single closed-suction drain is left in place until discharge or it produces <50 mL/day off of suction.
• Patients ambulate early
• The overwhelming majority of patients are discharged by the second postoperative day.
• The urinary catheter is left in place for 3-21 days postoperatively
  • Risk of removal before 7 days is associated with a 15-20% risk of urinary retention
  • Bladder spasms will generally spontaneously subside, and reassurance is often sufficient.
    • In cases of severe bladder spasms, an oral anticholinergic agent (oral oxybutynin [Ditropan] 5 mg) or diazepam (oral Valium, 5 to 10 mg) may be administered.
  • After the catheter has been removed, Kegel exercises should be initiated

Complications

• Intraoperative
  • Hemorrhage
    • <1% require intraoperative transfusion
    • If there is troublesome bleeding from the dorsal vein complex at any point, completely divide the dorsal vein complex over the urethra and oversew the end. This is the single best means to control bleeding from the dorsal vein complex.
  • Obturator nerve injury
    • Can occur during the pelvic lymphadenectomy
    • An attempt should be made at reanastomosis with fine non-absorbable sutures
    • When a tension-free primary nerve repair is not feasible, nerve grafting can be performed by a cutaneous or genitofemoral nerve graft.
    • Even without a nerve repair, conservative management with physical therapy can compensate for the deficit, and therefore many patients do not have a significant thigh aDDuctor deficit after the injury
  • Rectal injury
    • An infrequent (<0.3%) but serious complication
      • Occurs more commonly in salvage prostatectomy setting
        • Rates of rectal injury with salvage prostatectomy have decreased with increasing experience
    • Occurs during apical dissection while attempting to develop the plane between the rectum and Denonvilliers fascia
    • Methods to detect rectal injury:
      • Insert gloved finger through anus and look for rectal defect
      • Fill pelvis with saline and inject air through rectum
    • When rectal injury occurs, the prostatectomy should be completed, the bladder neck should be reconstructed, and hemostasis should be excellent.
    • Principles of Rectal Injury Repair
      1. General surgery consultation
      2. Copious irrigation of wound with antibiotic solution
      3. Excellent visualization of the extent of rectal injury and freshen edges of the rectal wound
      4. Multi-layer closure
      5. Interpose omentum between the rectal closure and the vesicourethral anastomosis to reduce the possibility of a rectourethral fistula.
         • Can be accomplished by making a small opening in the peritoneum; finding the omentum and fashioning a slender, well-vascularized pedicle that will be long enough to reach the pelvic floor; dividing the peritoneum in the rectovesical cul-de-sac; and feeding the end of an omental pedicle through this opening. The anal sphincter is digitally dilated widely by an assistant, and the rectal injury is clearly delineated.
         • The vesicourethral anastomosis is performed after suturing the omental pedicle in place.
      6. Post-operative antibiotics
      • • Several days on broad-spectrum antibiotics for both aerobic and anaerobic bacteria.
    • Indications to consider a diverting colostomy (3):
      1. Large rectal defect
      2. History of pelvic radiotherapy
      3. Long-term pre-operative glucocorticoid therapy
  • Ureteral injury
    • Very rare
    • Usually occurs secondary to inadvertent dissection within the layers of the trigone while attempting to identify the proper cleavage plane between the bladder and seminal vesicles.
    • If this injury occurs, ureteral reimplantation should be undertaken.
• Early post-operative complications
  • Ileus, wound infection, UTI
  • Thromboembolic events
    • DVT with PE is a major cause of mortality after RP.
    • Highest likelihood 14-28 days after the procedure.
    • Support stockings and early ambulation are recommended.
      • Prophylactic anticoagulation and sequential compression devices are advisable in patients at high risk for thromboembolic complications. However, perioperative subcutaneous heparin injection may predispose to lymphoceles, and many surgeons reserve pharmacologic prophylaxis for high-risk patients
  • Lymphocele
    • Pelvic lymphoceles can cause compression of the bladder resulting in reduced capacity and increased urinary frequency and urgency.
      • The possibility of a pelvic lymphocele should be ruled-out in patients who present with new onset, worsening irritative voiding symptoms and incontinence following uneventful robotic prostatectomy. These patients can often be misdiagnosed as experiencing normal post-operative recovery of urinary continence and be prescribed pelvic physiotherapy and anticholinergic medications.
  • Urine leak
  • Life-threatening delayed hemorrhage
    • Rare
    • Patients requiring acute transfusions for severe hypotension after radical prostatectomy should be explored early to evacuate the pelvic hematoma.
      • In patients managed non-operatively, the pelvic hematoma may drain through the urethrovesical anastomosis, resulting in symptomatic bladder neck contractures and long-term problems with continence.
• Late post-operative complications
  • Bladder neck contracture
    • Arises from inadequate coaptation of the mucosal surfaces.
    • May be due to (3):
      1. Inadequate approximation at the time of surgery
      2. Urinary extravasation
      3. Distraction of the bladder neck from a hematoma.
    • Should be considered in any patient who complains of a poor urinary stream or in patients who have prolonged unexplained incontinence
    • Management:
      • Options:
        • Simple cystoscopic dilation
        • Direct cold-knife incision of the bladder neck at 3-, 6-, and 9-o’clock followed by intermittent self-catheterization for a limited time.
        • Injection of triamcinolone acetonide (200 mg in 5 mL) at the bladder neck after cold-knife incision may be useful in patients with recalcitrant bladder neck contractures.
  • Urinary Incontinence
    • Generally good outcomes
      • Relatively few require implantation of an artificial urinary sphincter or a sling procedure for stress urinary incontinence.
    • Varies according to (2):
      1. Patient age
         • Mostly closed associated with continence
           • ≈95% of males < 60 years can attain pad-free urinary continence after surgery
           • 85% of males > 70 years regain continence
      2. Experience and skill of the surgeon
      • A 2014 meta-analysis found that nerve-sparing in patients undergoing radical prostatectomy was associated with improved time to continence but not long-term continence rates§
      • A 2015 meta-analysis found that nerve-sparing technique, not nerve-sparing, was associated with improved long-term continence§
  • Erectile Dysfunction:
    • Factors predicting recovery of erectile function after radical prostatectomy:
      1. Age of the patient (younger than 65 years)
      2. Status of potency pre-operatively
      3. Extent of nerve-sparing surgery
      • • ≈26% of males who underwent bilateral sural nerve grafting demonstrated full erections (sufficient for penetration). Sural grafts are placed in reverse to the natural position (proximal to distal and distal to proximal).
        • Up to 70% of the patients were potent postoperatively in a series of radical perineal prostatectomy patients.
        • Pharmacotherapy has been demonstrated to improve potency outcomes.
    • Erections usually begin to return as partial erections 3-6 months after surgery and may continue to improve for up to 3 years or more
    • In those who maintain erectile function following radical prostatectomy, the erection is generally less firm than it was preoperatively
    • Patients should be encouraged to use erectile aids postoperatively, including PDE5 inhibitors, intraurethral suppositories, intracavernosal injections, or vacuum erection devices. Erection rehabilitation programs using intracavernosal injection therapy or PDE5 inhibitors might hasten the return of erections and increase the proportion of men who recover erections
    • “On-demand,” rather than nightly, administration of PDE5 inhibitors may be more efficacious in men with erectile dysfunction after bilateral nerve-sparing radical prostatectomy
  • Urethral stricture
  • Hernia

References

• Wein AJ, Kavoussi LR, Partin AW, Peters CA (eds): CAMPBELL-WALSH UROLOGY, ed 11. Philadelphia, Elsevier, 2015, chap 114