Full-thickness rectal prolapse





Introduction


Full-thickness rectal prolapse is a benign but debilitating condition involving full-thickness descent of the rectum through the anal canal ( Fig. 30.1 ). It is important to distinguish full-thickness rectal prolapse from simple prolapse of the rectal mucosa on physical examination ( Fig. 30.2 ). This chapter will focus on full-thickness rectal prolapse. The true cause of rectal prolapse is unknown, despite its long and extensive presence in medical history and literature. Numerous operations have been described in the literature since 1889, when Mikulicz described his series of six patients undergoing perineal excision for prolapse, and great variation in surgical management and approach still exists. In this chapter, we discuss the etiology, epidemiology, clinical features, evaluation, common surgical techniques, results, and our experience regarding rectal prolapse. This is an update from a previous chapter by , incorporating the latest clinical evidence and decision-making.




Fig. 30.1


Full-thickness rectal prolapse showing concentric folds of rectal mucosa indicating full–thickness protrusion of the rectum.



Fig. 30.2


Partial-thickness mucosal-only prolapse showing short segment protrusions and radial folding of the mucosa.


Etiology


A renowned English colorectal surgeon, Hugh Lockhart-Mummery of St. Marks’ Hospital in London, wrote in 1972: “It is interesting to note that we still know so little about the cause of such a common condition.” The most current and accepted theory was proposed by after they demonstrated with cinedefecography that full-thickness prolapse starts as an internal intussusception of the rectum with a lead point proximal to the anal verge. Years later, radiopaque markers were applied to the rectal mucosa in studies to demonstrate this phenomenon in real time and support the current theory that rectal prolapse is attributed to internal intussusception of the rectal wall.


There are many common anatomic features that may relate to rectal prolapse: a deep peritoneal cul-de-sac or pouch of Douglas, enterocele, loss of posterior rectal fixation, a patulous anal sphincter, diastasis of the levator ani, redundant rectum and sigmoid colon, and loss of the rectum’s horizontal position may all contribute to the pathology. It is unclear whether these findings are a cause of the rectal prolapse, or if they are merely associated abnormalities. The goals of any operation to repair rectal prolapse should be to correct the prolapse of tissue, avoid worsening any concurrent issues such as incontinence or constipation, and avoid causing new problems, particularly new-onset constipation.


Epidemiology


Rectal prolapse is a relatively uncommon phenomenon, occurring in an estimated 0.5% of the population; however, the true incidence and prevalence are unknown, primarily because of underreporting, especially in the elderly population. The peak incidence is in the seventh decade of life, and it occurs more commonly in women, who are six times more likely to suffer from prolapse than are men ( ). Although rectal prolapse is often associated with multiparity, nearly one-third of women with rectal prolapse are nulliparous. Male patients, although they represent a very small portion of this population, generally develop prolapse at a younger age than female patients (<40 years). There is also an association between younger presentation and psychiatric conditions requiring multiple medications, such as autism and developmental delay.


Clinical features


Patients with rectal prolapse generally present with fecal soilage, prolapse of tissue through the anal sphincter complex, mucoid discharge, and bleeding. Although the precise pathophysiology is unclear, found that 18% of patients with prolapse reported straining, and 42% had constipation as the most common associated symptom.


A complete assessment of female patients with rectal prolapse should include evaluation for constipation, urinary and fecal incontinence, and other pelvic floor disorders such as uterine prolapse, rectocele, cystocele, or enterocele. Staged or combined surgical correction of pelvic floor disorders, should they exist concurrently, is imperative for resolution of symptoms.


Evaluation


Patients are often quite anxious when they present for evaluation for rectal prolapse. After a complete history of the type and duration of symptoms, a simple examination in the office is often sufficient. Symptoms related to fecal and urinary incontinence and constipation should be especially emphasized.


Physical examination entails visual inspection of the perineum, which often reveals a patulous anus. Additionally, mucous soiling of the perineum is often present because of the chronic external prolapse of the rectum. The examiner should be sure to rule out the presence of any palpable masses, and proctoscopy should be done to rule out a malignancy as a potential lead point. If the patient is overdue for a screening colonoscopy, or if symptoms suspicious for cancer are present, they should be referred for colonoscopy before surgical correction of the prolapse. Occasionally, rectal prolapse is not externally visible on initial examination. Examination of the patient in a squatting position or with Valsalva maneuver on a commode may be needed to reproduce the prolapse, but this is a necessary maneuver to distinguish between full-thickness and mucosal prolapse. During inspection, it is important to differentiate full-thickness rectal prolapse (concentric folds) from prolapsing internal hemorrhoids (radial invaginations) (see Figs. 30.1 and 30.2 ). Associated vaginal prolapse such as rectocele (posterior vaginal prolapse), cystocele (anterior vaginal prolapse), or enterocele (prolapse of small intestine, usually at the vaginal apex or posterior vagina) should be identified, if present.


When outlet obstruction or pelvic support disorders are suspected, defecography should be performed. (See Video 13.1 for a detailed description and demonstration of defecography.) This may provide important information like the presence of additional pathology, such as enterocele, rectocele, sigmoidocele, or concomitant vaginal vault prolapse. Additionally, looking at the anorectal angle at rest and straining can be used to assess for appropriate relaxation of the puborectalis muscle and whether or not conditions such as anismus need to be addressed before surgery. Although additional tests such as anal physiology testing can be done, they are typically not necessary in the work-up of an isolated rectal prolapse.


Nonsurgical options for prolapse


No studies exist that compare operative repair with nonoperative therapy for rectal prolapse, nor are there definitive nonoperative alternatives to correct this condition. Aggressive treatment of constipation, if present, with medications may lessen symptoms. Applying table sugar to the prolapsed segment draws edema out of the segment and may facilitate reduction of the prolapse. Placing the patient in Trendelenburg position and administering intravenous benzodiazepines may ease reduction as well. However, none of these nonsurgical options will definitively repair prolapse, and surgery continues to be the preferred treatment.


Common surgical repairs for prolapse


There are more than 300 procedures described to treat rectal prolapse, and new techniques are continually introduced in the literature. Despite this, there is no single operation that is preferred over the rest, and choosing the most appropriate procedure depends on individual patient factors. These factors include medical comorbid conditions, risk of recurrence, bowel function (fecal incontinence and constipation), degree of prolapse, and presence of associated pelvic disorders. Regardless of approach, the goals of any prolapse surgery are to treat the prolapse and to address associated constipation or incontinence.


Procedures for rectal prolapse can be classified into two main categories: perineal and transabdominal repairs. Perineal repairs are less invasive, cause less perioperative pain and morbidity, and are associated with reduced lengths of stay. They are often favored for frail, elderly patients, but at some institutions perineal repairs are recommended in healthy patients, too. The perineal approach includes a risk of infection and complications related to the suture line or wound. In addition, the perineal approach is known for recurrence rates that are four times higher than those of transabdominal operations; thus, the abdominal approach is often favored for medically-fit patients who can tolerate this operation.


A transabdominal repair requires general anesthesia and may have more devastating complications, such as anastomotic leak, abdominal sepsis, stricture, and adhesions. The introduction of minimally invasive approaches since the 1990s has added a new dimension to transabdominal prolapse surgery and has been shown to reduce postoperative convalescence, making this approach more appealing. Historical data have suggested a higher incidence of complications following an abdominal approach, and higher recurrence with a perineal approach. randomized 293 patients with rectal prolapse to abdominal versus perineal surgery. Recurrence occurred in 20% of perineal procedures and 26% of abdominal procedures ( P = .80). However, the recurrence from abdominal procedures in this study was much higher than that typically reported in the literature. In another small study, randomized 50 patients to ventral mesh rectopexy versus Delorme procedure. Clinical recurrence occurred in 8% of abdominal procedures versus 16% of perineal procedures ( P = .66).


Perineal repairs


Mucosal sleeve resection (delorme procedure).


The choice between a mucosal sleeve resection such as Delorme or a full-thickness procedure such as an Altemeier is at the discretion of the surgeon, as most will choose the method they are most comfortable with. After positioning the patient, the perineum and vagina are prepared with an aseptic solution. The operation commences by injecting 1:100,000 epinephrine solution circumferentially into the submucosal plane just proximal to the dentate line. This allows delineation of the dissecting plane and diminishes blood loss. Using electrocoagulation, the dissection begins in circumferential manner 1 to 1.5 cm above the dentate line ( Fig. 30.3 ), creating a plane between the submucosa and the internal anal sphincter. Once this plane is started, the free edge of the mucosa and submucosa is tagged with sutures for ease of handling and in creating traction for easier dissection. Continuing in a circumferential direction and using liberal amounts of injectable saline in the plane between the submucosa and the muscular cuff, scissors are used to divide the attachments and to deliver the submucosa and mucosal cuff out of the rectum and anus ( Fig. 30.4 ). Penetrating blood vessels encountered during the dissection can be treated with electrocoagulation. It is important to maintain strict hemostasis during the dissection to avoid hematomas after the procedure. The dissection continues until the rectal mucosa cannot be pulled down any farther; usually, 10 to 15 cm can be mobilized. During this phase of the operation, we use copious amounts of antibiotic solution such as tetracycline to irrigate the surgical field. After the dissection is completed, the rectal muscle is plicated with suture such as No. 2-0 Polyglactin 910 suture on a UR-6 needle (Vicryl; Ethicon, Inc., Somerville, NJ). A total of eight sutures are spaced circumferentially for this plication. The dissected mucosa is excised, and the proximal line of resection is approximated to the distal incision line. Interrupted sutures of No. 2-0 Vicryl on a UR-6 needle work well for this circumferential suture line ( Fig. 30.5 ).




Fig. 30.3


Incision for a Delorme procedure 1 to 1.5 cm above the dentate line. The incision goes through the mucosa and submucosa initially, stripping this tube from the underlying internal anal sphincter and, more proximally, from the rectal muscular cuff.



Fig. 30.4


Delorme procedure with stripping of the mucosa.



Fig. 30.5


Completed Delorme procedure. Notice that the rectal wall is plicated with sutures in an accordion-type fashion and is situated above the anal sphincters. The anastomosis is just above the dentate line.


The reported rate of prolapse recurrence after the Delorme procedure varies from 10% to 15% in different series. The procedure is well tolerated in high-risk patients but still carries a risk for complications of bleeding, urinary retention, and fecal impaction in up to 12% of patients. In general, constipation and fecal incontinence tend to improve after surgery, the latter perhaps owing to the rectal muscular wall plication that creates a bulky, donut-like circumferential mass around the upper anal canal.


Perineal rectosigmoidectomy (altemeier procedure).


Perineal rectosigmoidectomy was first described in 1889 by Mikulicz; in 1952, Altemeier and coworkers described excellent results in elderly debilitated patients. This approach involves a full-thickness removal of the rectum and sigmoid colon via the perineum, with a coloanal anastomosis. This is a minimally invasive procedure, which is ideal for patients deemed too unhealthy for an abdominal procedure. However, in patients who have undergone previous rectal or sigmoid resections, care must be exercised in performing this operation, as the inferior mesenteric vessels may have been previously ligated, and the blood supply to this area may have been altered. Another application of this procedure is in the setting of incarcerated, irreducible prolapse.


First, the prolapse is established by gentle traction with the use of Allis or Babcock clamps. A circumferential incision is made 1.5 to 2.0 cm above the dentate line ( Fig. 30.6 ) with electrocautery or a scalpel. The incision is deepened through the muscular layer until perirectal fat is encountered ( Fig. 30.7 ). Mesorectal vessels are ligated ( Fig. 30.8 ), proceeding in a circumferential manner. As the dissection continues in the cephalad direction, a hernia sac may be encountered anteriorly and opened, and the abdominal cavity may be entered ( Fig. 30.9 ). When no additional bowel can be delivered without tension, the bowel is marked, as this will become the line of transection ( Fig. 30.10 ). At this stage, particularly in incontinent patients, a levatorplasty can be performed by placing sutures such as No. 2-0 polypropylene suture (Prolene; Ethicon, Inc.) anteriorly to loosely approximate the levator muscles. The prolapsed rectal segment is transected ( Fig. 30.11 ). An anastomosis is created with circumferential full-thickness interrupted No. 2-0 Vicryl sutures ( Fig. 30.12 ).




Fig. 30.6


Altemeier procedure (perineal proctosigmoidectomy). An incision is made with electrocautery (as shown here) or knife 1.5 to 2 cm above the dentate line. Note that the patient is in the prone jackknife position.



Fig. 30.7


The incision for the perineal proctosigmoidectomy divides all layers of the rectal wall until the extrarectal fat is encountered.



Fig. 30.8


The mesorectal vessels are divided and ligated.



Fig. 30.9


The anterior peritoneal reflection is opened to enter the pelvis and allow more proximal dissection.

Nov 27, 2021 | Posted by in GYNECOLOGY | Comments Off on Full-thickness rectal prolapse
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