Patient selection and indications for surgery
In situ neobladder surgery has a number of contraindications. Similar to the indications for radical cystectomy for bladder cancer, bone, lung and lymph node metastases must be excluded preoperatively to determine the need for surgery. Patients with severe hepatic, renal or small bowel insufficiency, or urethral sphincter dysfunction must be treated with alternative urinary diversions. The presence of urothelial cancer or a pre- or postoperative paraurethral biopsy suggesting the presence of tumor at the margin of the future anastomosis is an absolute contraindication.
The most important factor determining the success of in situ cystectomy is the patient’s ability to accept long-term follow-up compliance. The patient must be physically and mentally healthy and able to recognize and understand the new bladder and how it functions. Without these prerequisites, only other urinary diversion options can be considered. Postoperative patient management is more important than surgical manipulation if good long-term outcomes are to be achieved.
Patient preparation and position
Preoperative bowel preparation requires only two clean enemas. Subcutaneous injection of low-molecular heparin into the upper extremity starting the evening before surgery to prevent deep vein thrombosis also helps to prevent postoperative pelvic lymphatic cyst formation. Patients are allowed to use compression stockings and are started on the floor on the first postoperative day. Intraoperative amoxicillin/clavulanic acid, aminoglycosides and metronidazole were started to prevent infection, with aminoglycosides and metronidazole continued for 48 h, while amoxicillin/clavulanic acid was not discontinued until all drains and urinary catheters were removed.
Patients were prepared only when they were about to undergo surgery, which was performed in a mildly hyperextended supine position. Operative instruments for total cystotomy and ileal bladder were sufficient for the procedure. Curved Babcock forceps were used to handle the dorsal penile vein complex, and no special instruments were required to create the urinary storage bladder.
Intraoperative sutures used include.
– No. 0 absorbable thread, FSL needle – ligation of the dorsal venous complex
– No. 0 absorbable thread, UR-5 stitches – suturing the dorsal venous complex
– 4C0 absorbable thread, V-5 stitches – anastomosis of the ureter and neobladder
– 4C0 absorbable thread, RB-1 plus stitch – securing ureteral catheter to ureter
– 2C0 absorbable thread, SH stitch – suturing of the neobladder
– 2C0 absorbable thread, UR-6 stitches – urethral anastomosis
Preoperative planning and preparation checklist includes.
-Patient consent for long-term postoperative follow-up
-good psycho-psychological status and good physical activity
-Blood creatinine level <150 mmol/L
– Good liver function
-Good bowel function
-No tumor in the distal urethra, pars seminis (male) or bladder neck (female)
-Good urinary control
-Prevention of deep vein thrombosis
-Prophylactic use of antibiotics
-Overstretched supine position
Figure 1
The length of the ileo-intestinal segment required to construct the urinary storage sac was approximately 54 cm, taken from 25 cm from the ileocecal region, and the intestinal continuity was restored using a single continuous plasma-muscle anastomosis with 4-0 absorbable thread. The length of the ileal intestinal segment was measured using a ruler, and a 10-cm or 15-cm segment was measured at a time along the mesenteric margin, without stretching the intestinal tube during the measurement. Flush the intestinal canal. Avoid epidural anesthesia because it can cause spasm of the intestinal canal, which can make the canal “shorten” and appear too long when the canal is relaxed. The distal mesentery can be transected to the primary arch vessels, while the proximal mesentery should not be dissected too much to protect the primary arch vessels and thus allow for a better blood supply to the future urinary bladder.
Figure 2
The mesenteric fissure is closed with continuous sutures using 2C0 absorbable thread. The sutures must be superficial when suturing the mesentery of the urinary bladder in order to protect the new blood supply. A single continuous pulpy suture with 4C0 absorbable thread is used to close the two broken ends of the ileocecal segment. The distal 40-44 cm of the ileocecal segment is opened along the opposite mesenteric margin.
Figure 3
The distal end of the ureter was split 1.5-2 cm and the input loops of the ureter and the storage sac were anastomosed with 4-0 absorbable thread by continuous sutures according to the Nesbit method. That is, the two ureters were anastomosed separately by using the end-lateral anastomosis method to anastomose the ureter with the ileal input loop of the storage bladder with a median paramedian longitudinal incision of the opposite mesenteric margin. A 7F or 8F ureteral catheter is placed into the ureter. To prevent slippage of the ureteral catheter, the ureter and stent tube are sutured together at 3-4 cm proximal to the anastomosis with a quick absorbable 4C0 suture. The knot should be tied very loosely so as not to interfere with the ureteral blood supply. The tissue surrounding the most distal part of the ureter is sutured to the ileal input loop to reduce the tension on the anastomosis.
Figure 4
The ureteral catheter is passed through the mesenteric-covered intestinal wall at the most distal end of the input loop. This allows the intestinal wall fistula to close on its own after the ureteral stent tube is sequentially removed 5-8 days postoperatively. The open intestinal tube is folded into a U-shape and then the middle two sides are sutured continuously using 2-0 absorbable thread to construct a urinary storage capsule.
Figure 5
The two ends of the U-shaped bowel loop are then folded in half to form a spherical urinary storage bladder containing four folded ileal segments.
Figure 6
With the lower half of the anterior wall opening completely closed and the upper half half half closed, the surgeon inserts a finger through the opening to find the lowest point of the urinary bladder. An opening of 8-10 mm in diameter is made at the lowest point of the storage bladder, which should be close to the mesentery and 2-3 cm from the folded edge of the ileum, taking care to leave the suture. The outlet should be parallel to the pelvic floor and not form a funnel shape to prevent torsion.
Figure 7
The lower opening of the neobladder is anastomosed to the membranous urethra with 6 2-0 absorbable sutures. The 2 posteriormost paramedian sutures are passed through Denonvilliers’ fascia and carry only 3-4 mm of extra-membranous urethral tissue. The two anteriormost stitches carry only a minimal amount of urethral tissue and pass through the deep dorsal penile vein complex. The lateral two stitches are made with 3-4 mm of extraurethral tissue and only a small amount of tissue at the edge of the urethral mucosa. By suturing between the exit edge of the intestinal wall of the urinary bladder and the urethral mucosa, the two are perfectly aligned so that the plasma muscle layer of the urinary bladder and the urethral sphincter are well aligned. This prevents the mucosa of the small intestine from lying between the muscle layers and reduces the chance of postoperative anastomotic fistula. Tension on the anastomosis can be reduced by suturing with the dorsal Denonvilliers’ fascia and the ventral ligature of the deep dorsal penile vein complex. The 18F urethral tube was inserted before tying the 6 sutures together, tying the two ventral stitches at points 1 and 11, followed by the middle stitches at points 3 and 9, and finally the dorsal stitches at points 5 and 7.
Figure 8
The 10F cystostomy tube is placed into the storage bladder through the fatty part of the mesentery before completely closing the storage bladder. The urinary bladder is then flushed to remove any clots and checked for leaks.
Postoperative care
The urinary catheter and suprapubic fistula are flushed with saline every 6 hours to prevent the risk of rupture of the new bladder due to catheter blockage. This risk is greatest when bowel function is restored and the urinary catheter is still in place.
Parenteral nutrition was started on the first postoperative day and stopped as soon as the patient resumed eating and drinking. Parasympathomimetic drugs (e.g., subcutaneous 0.5 mg neostigmine for 3-6 days) can be added starting 3 days after surgery to prevent postoperative bloating and to promote recovery of bowel function. The external ureteral catheter can be flushed if ureteral obstruction is suspected. Ureteral catheters are sequentially removed 5-8 days postoperatively. The suprapubic fistula can be removed 8-10 days postoperatively after the urethrocystography has ruled out leakage. The ureter is removed 48 hours after the removal of the fistula to facilitate the healing of the suprapubic fistula. The risk of metabolic acidosis is significantly increased after removal of the urinary catheter. If patients develop acidosis, they may complain of drowsiness, fatigue, nausea, vomiting, anorexia, and burning sensation in the abdomen. Acidosis can be detected by monitoring alkaline residuals with venous blood gas analysis, initially once every 2-3 days and subsequently at longer intervals depending on the blood gas profile. If the alkaline residual is negative, it needs to be corrected. Practically all patients need to be treated with sodium bicarbonate (2C6 g/day) for 2-6 weeks. The salt loss syndrome caused by the urinary bladder can cause hypovolemia, dehydration and weight loss. Therefore, it is important to ensure 2-3 L of fluid intake per day postoperatively, as well as to increase the patient’s dietary salt intake; weight is also monitored daily.
Patients can urinate on their own early on in a sitting position, once every 2h during the day and once every 3h at night by setting an alarm clock. During urination, the pelvic floor muscles should be relaxed and then the abdominal pressure should be slightly increased. Urination can be assisted by hand pressure on the lower abdomen and bending forward. Residual urine was earlier measured by catheterization combined with suprapubic ultrasound and is now measured using ultrasound only. Patients presenting with urinary tract infections and bacteriuria should be managed aggressively. If the results of blood gas analysis show that the organism is well compensated, the voiding interval can be gradually extended (by 1 hour at a time) from 2 h to 4 h. The patient must extend the voiding interval thus increasing the bladder volume to the ideal capacity of 500 ml, which should be maintained even if incontinence occurs. Laplace’s law (pressure = tension/radius) states that as the radius of the bladder increases, the pressure inside the bladder decreases, creating a low pressure system.
The ability to control urine after surgery is related to the following factors: surgical technique (intraoperative protection of the urethra and pelvic floor nerves), pelvic floor muscle training and the age of the patient. The patient can be taught to perform effective sphincter training by rectal palpation. The examiner can instruct the patient to adjust the sphincter contraction training by perceiving the sphincter contraction force with the finger, so that the patient can contract only the anal sphincter, which will ensure that the patient can perform satisfactory sphincter training in the future. Pelvic floor sphincter training should be maintained daily with 10 contractions per hour, each contraction lasting 6 seconds, until more satisfactory urinary control is achieved.
Difficulties
Stumpy patients have the greatest difficulty in performing in situ bladder surgery because of their narrow pelvic cavity. The ileocecal mesentery used for the urinary storage bladder is thick in these patients. Folding the ileocecal segment into a spherical shape is therefore more difficult, but usually successful. The mesentery is also shorter in these patients, resulting in a longer distance between the urinary bladder and the urethra than expected. In order to obtain sufficient length to achieve a tension-free anastomosis, the distal mesentery must be dissected and released to the greatest extent possible without damaging the blood supply to the urinary bladder or ileum. The peritoneum on the mesenteric surface of the urinary bladder is carefully incised in a direction perpendicular to the mesenteric vessels, thus allowing further lengthening of the mesentery. The sigmoid colon or small intestine between the mesentery of the urinary bladder and the sacral promontory must be removed prior to anastomosis of the urinary bladder to the urethra. The distance between the urinary bladder and urethra can be shortened by stretching or bending the pelvis appropriately. A stitch can be placed on each side of the anastomosis to reduce the tension on the anastomosis by bringing the urinary bladder to the pelvic floor. With these methods, construction of a tension-free anastomosis is usually achievable.