Rectal prolapse

What is rectal prolapse?

Rectal prolapse is a condition in which the rectum (the last part of the large intestine before the anus) loses its normal attachments that keep it fixed inside the body and slips outside the anus, turning itself inside out. Although this can be unpleasant, it rarely leads to a medical emergency. However, it can be quite bothersome and can often impact negatively the patients’ quality of life.
Overall, rectal prolapse affects relatively few patients (2.5 cases / 100,000 people). This condition mainly affects adults and women over 50 are six times more likely than men to experience it. Most women with prolapse are usually in their 60s, while the few men who develop prolapse are much younger, with an average age of 40 or younger. In these younger patients, there is a higher rate of autism, developmental delay, and psychiatric problems that require multiple medications.
Although not always required, the definitive treatment of rectal prolapse is surgical.

Risk factors

While several factors appear to be related to the occurrence of rectal prolapse, there is no definite cause of the condition. Chronic constipation (irregular bowel movements or straining) is present in 30-67% of patients, while an additional 15% experience diarrhea. There is a hypothesis that the occurrence of rectal prolapse is a consequence of multiple vaginal deliveries. However, up to 35% of patients with prolapse are asymptomatic.

Occurrence

Rectal prolapse tends to occur gradually. Initially, prolapse occurs with bowel movements, and then the rectum returns to its normal position. Patients may later describe a mass or “something falling out” that they may have to “push back” after a bowel movement. Until the rectum retracts, patients may feel like they are “sitting on a ball.” Rectal prolapse can be confused with serious hemorrhoid disease and can even be a diagnostic problem for physicians who do not often see patients with the condition.
Once prolapse becomes apparent, fecal incontinence (inability to control gas, liquid, or solid bowel movements) occurs in 50-75% of cases and may be due to a variety of factors. The anal sphincter is a structure made up of many muscles that allow one to control and retain the contents of the bowel when they have the urge to have a bowel movement. When the rectum prolapses, it passes through the anal sphincter and this allows stool and mucus to escape uncontrollably. Pelvic nerve (vulva nerve) damage has been found in many patients with prolapse. The vulva nerve contributes to the control of the anal sphincter, and damage can be caused by direct trauma (birth injury), chronic diseases such as diabetes, and by injury or surgery to the lower back. The anal sphincter is constantly stretched by the prolapse itself, adding an additional risk factor for incontinence.

More than 25% to 50% of patients will report constipation. Constipation associated with prolapse can result from the accumulation of contents in the rectum, creating an obstruction that deteriorates with increasing strain, generalized problems of coordination with the pelvic floor, and problems with the colon’s ability to propel contents forward at a normal rate. It is not unusual for some patients to experience periods of constipation and periods of incontinence.
Over time, the rectal mucosa may thicken and ulcerate with significant bleeding. Rarely, the prolapse can become strangulated outside the anus – a condition that could require emergency surgery.

Investigation of patients with prolapse

Prior to potential surgery, the patient’s medical history is obtained and a careful physical examination is performed. As mentioned above, attention should be focused on the presence of constipation, fecal incontinence and the possible presence of urinary incontinence (inability to control urine) or vaginal swelling.
Direct examination of the anal area is important and often reveals low tone of the anal sphincter (the sphincter appears “loose”). The patient may be asked to tighten and relax the anal sphincter while the doctor places a finger in the patient’s rectum. This helps the doctor get a sense of how well the anal sphincter is working. Standard rectal manometry (a test that directly measures anal sphincter pressures) could be performed, as low sphincter pressures may influence the choice of surgery to repair rectal prolapse.
While a spontaneous prolapse is obvious, there can be a diagnostic problem between significant hemorrhoidal disease and rectal prolapse. To demonstrate rectal prolapse, the patient may be asked to flex while being observed sitting on a toilet or chair. While this can be somewhat distressing for patients, it is very important to make an accurate diagnosis, as the treatments for hemorrhoids and rectal prolapse are quite different.
A colonoscopy is often necessary to rule out a polyp or a neoplasm before choosing treatment for rectal prolapse. A colonoscopy is a procedure where a long, flexible instrument called a colonoscope is used to examine the entire inside of the colon (large intestine) and rectum.
When the diagnosis remains in doubt, a defecogram can reveal the problem. During this examination, the patient is given an enema containing a radiopaque contrast medium, and then x-rays are taken during the bowel movement. Occasionally, additional contrast may be administered orally or vaginally. As mentioned, rectal prolapse can occur in the case of a generalized pelvic floor problem. About 20% to 35% of patients with prolapse experience urinary incontinence, while another 15% of women have significant vaginal prolapse (a bulging feeling in the vagina). These additional problems may also be demonstrated on a defecogram and may require surgery, which usually involves the intervention of other surgical specialties during the surgical repair of the prolapse. Importantly, if these additional issues are not addressed during rectal prolapse repair, the symptoms associated with these problems may worsen.

As mentioned, many patients will experience rectal prolapse with chronic constipation. Depending on the severity of symptoms, a patient may need to undergo a transit study to assess the colon’s ability to move contents through. A colonic transit study involves swallowing a capsule containing multiple markers that are imaged on an abdominal x-ray. A number of x-rays are then taken over a five-day period to visualize how the capsule moves through the small and large intestine, referred to as “transit time”. Patients with an unusually long transit time may benefit from resection of part or, less likely, all of the colon during prolapse repair.

What happens if a patient chooses not to treat rectal prolapse?

Patients that have been evaluated by a surgeon familiar with the diagnosis and treatment of prolapse and has been diagnosed with rectal prolapse, could potentially choose not to do anything about it. Patients who choose not to treat the problem should expect that their prolapse will likely worsen over time and that the rectum will prolapse more easily (it may just appear in an upright position). If a patient chooses to delay treatment for an extended period of time, they should be aware that the longer the prolapse remains untreated, the greater the chance of permanent fecal incontinence problems, as the anal sphincter continues to stretch and the potential for nerve damage is also increasing. The length of time it takes for these differences to appear is widely variable and varies from person to person. In some cases, the prolapse is too small or the patient is too frail to undergo surgery. In these cases, conservative means such as special underwear can prevent recurrent rectal prolapse.
If left untreated, rectal prolapse does not turn into malignancy.

Surgery for rectal prolapse

There are two general approaches to surgery for rectal prolapse – transabdominal procedures (through the abdomen) and perineal procedures (from the anus). Both approaches aim to prevent recurrence of prolapse and usually result in a significant improvement in quality of life.
The type of surgery chosen depends on factors related to both the patient and the procedure. Patient factors include the patient’s age, sex, bowel function, continence, previous surgeries, and comorbidities. Factors related to surgery include the extent of prolapse, the effect of surgery on bowel function and incontinence, complication rates, recurrence rates, and surgeon experience.
The majority of surgeons would agree that if a patient is a viable candidate for surgery, the abdominal approach may have a better chance of a long-term successful rectal prolapse repair. The perineal approach is often a better choice for very elderly patients or for patients with very severe comorbidities other than rectal prolapse. A perineal approach may also be considered in young men, as there is a small chance (1-2%) of sexual dysfunction due to nerve injury while preparing the pelvis as part of an abdominal approach. While this is very uncommon, it should be taken into account when making decisions about the type of surgery. Young men may need to consider sperm storage before surgery, in the very rare event that they experience sexual dysfunction afterward.
Rectal prolapse surgeries can be performed under various types of anesthesia. The patient and the surgeon can decide what is appropriate for each patient according to their particularities. Possible options include:
• General anesthesia (patient in deep sleep with “breathing tube” inserted)
• Spinal anesthesia (similar to an epidural injection during labor)
• A combination of intravenous relaxant drugs and local anesthesia (a drug that “numbs” the area) injected around the anus after the relaxant drugs are given. This is called monitored anesthesia with perianal block.

 

Transabdominal Approaches

Transabdominal colopexy with possible colectomy
Most transabdominal techniques involve making an incision in the lower abdomen and dividing the loose attachments of the rectum with the pelvic walls down to the pelvic floor. A colopexy is then performed, in which the rectum is pulled up and anchored to the sacrum (back of the pelvis) in various ways. Depending on the surgeon’s preference, the rectum may be sutured directly to the sacrum or a prosthetic material (mesh) may be placed. Regardless of the specific technique used, the goal is to keep the rectum in place until scar tissue has formed to fix it. Overall, both of these techniques have very good results, with recurrence of the prolapse limited to approximately 2-5% of cases.
When patients report a history of chronic constipation, removal of a portion of the colon may be included in the operation in an attempt to improve bowel function. The size of the part of the colon removed is determined by the severity of the constipation and may depend on the results of the previously described colon transit study. Interestingly, in patients with fecal incontinence before surgery, this symptom improves in about 35% of patients, even with part of the colon resected. This improvement often occurs within 2 to 3 months.
It is important to note that although prolapse can be repaired, functionality (incontinence or constipation) may not always improve. In a small number of cases, a possible complication of transabdominal colopexy is the development of new or worsening constipation. After colopexy, 15% of patients will experience constipation for the first time, and at least half of those who had constipation before surgery will see it worsen. It is unclear what accounts for these findings. Fiber, liquids, and stool softeners can be used to manage constipation after rectal prolapse repair of any type. Occasionally, mild laxatives may be needed temporarily after surgery. Some patients may report sexual dysfunction after extensive pelvic preparation included in this surgery.

Minimally invasive colopexy with possible colectomy

Minimally invasive techniques such as laparoscopy or robotic surgery are used in some centers with comparable success to conventional, open trans-abdominal operations. Laparoscopy refers to the use of small incisions through which the surgeon can insert a camera and surgical instruments, allowing him to perform the same procedures described above for transabdominal approaches.

The robotic approach similarly uses smaller incisions to perform transabdominal surgery with the assistance of a surgical robot. In each of these cases, the operation performed is the same as the open approach, only through smaller incisions and with the help of a camera. Potential benefits of a laparoscopic approach include less pain, a shorter hospital stay, and a quicker return to full activity and work. Complication rates appear to be lower than open procedures and recurrence rates appear to be the same as open procedures (less than 5%). Not all surgeons have the experience or expertise to perform these procedures, and therefore they may not be available in all centers.

 

Perineal approaches

It is generally believed that the perineal approach results in fewer complications and pain, with a reduced length of hospital stay. These advantages were until recently thought to be offset by higher recurrence rates. The most recent data are however inconclusive on this point, and a proper perineal operation may yield good long-term results.

Perineal rectosigmoidectomy

The most common perineal approach is often referred to as a perineal rectosigmoidectomy or “Altemeier procedure,” named after the surgeon who made it famous. This approach to rectal prolapse surgical repair is carried out through the anus, without an abdominal incision. During surgery, prolapse of the rectum is deliberately caused, the former then being divided. The extra rectum and colon are pulled down and out of the body. The rectum and colon are resected, with the remaining colon pulled down and sutured to the anus. The lack of an abdominal incision, minimal pain, and shorter hospital stay make this procedure an attractive option for suitable patients.
Patients undergoing perineal rectosigmoidectomy tend to be older and with more severe medical problems than those undergoing transabdominal repair. Additionally, patients with minor prolapse or patients with strangulated prolapse (the rectum does not return to position) where there is concern for a nonviable (or “dead”) rectum may need to undergo this procedure, even though medically they could undergo trans-abdominal surgery. Recurrence rates have been reported to be much higher (> 10%) than transabdominal approaches (2-5%). Complication rates range from 5-24% and include bleeding or leakage from the anastomosis into the pelvis and pelvic inflammation. Fecal incontinence may be a greater problem after this procedure compared to transabdominal colopexy, although most patients had pre-existing incontinence. The role of the rectum is to serve as a reservoir to hold the contents and this operation removes the rectum. This leaves the colon to take over the role of the rectum and may not be able to hold contents as effectively as the rectum. A plastic repair of the elevators can be performed to solve this problem. This repair takes place at the same time as the perineal rectosigmoidectomy and involves the “tightening” of the muscles of the pelvic floor by bringing some of them together with sutures. This appears to contribute to stool continence in about two-thirds of patients.

Rectal mucosal resection (Delorme’s procedure)

Occasionally, a surgeon may choose a perineal procedure less extensive than a perineal rectosigmoidectomy. Delorme’s procedure does not involve a full-thickness excision, as described in perineal rectosigmoidectomy. Instead, the inner lining of the rectum is separated from the muscle and removed. The rectus muscles are then folded and sewn back on themselves (folded) to reverse the prolapse. This operation may be appropriate to correct a small prolapse or if the prolapse is of full thickness but does not involve the entire diameter of the rectum, where a perineal rectosigmoidectomy may be difficult to perform. Incontinence improves in 40-50% of patients after this procedure.
The range of complications is quite wide (0-76%) and most are due to pre-existing medical problems. Complications associated with surgery are bleeding, anastomotic leakage, and rectal stricture. Prolapse recurrence rates (6-26%) appear to be higher than in perineal rectosigmoidectomy.

Questions For The Surgeon

• Do I need surgery?
• What are my options for surgery?
• What options do I have with regards to anesthesia for surgery?
• What should I expect after surgery?
• How do you plan to manage my pain after surgery?
• What if I do not want any treatment for rectal prolapse?