Current Therapy in Colon and Rectal Surgery Volume 7435 || RECTAL PROLAPSE
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23 - RECTAL PROLAPSE Conor P. Delaney, MD, MCh, PhD, FRCSI (Gen), FACS Anthony J. Senagore, MD, MBA, MS, FACS - Rectal prolapse occurs when the full thickness of the rec- tal wall protrudes through the anal canal. The condition is most commonly seen in older females, but may occur in both sexes and at any age. Although rectal prolapse has fascinated surgeons for many years, the optimal surgical approach has not been determined. Over 100 surgical operations have been reported, and these procedures can be grouped into perineal and abdominal approaches. Choosing the optimal repair for an individual patient involves consideration of many factors, including the patient’s general health and whether there is a history of constipation (present in 25 to 50%) or fecal incontinence (present in approximately 75%). ■ PATHOPHYSIOLOGY The mechanisms by which prolapse occur remain poorly understood. Broden and Snellman suggested that pro- lapse is initiated by a midrectal intussusception, which commences 8 to 10 cm inside the rectum. One initiating factor may be chronic straining, which might explain the association with colitis cystica profunda and solitary rec- tal ulcer. Prolapse is also thought to be related to abnor- mal intestinal motility, such as is seen in slow-transit constipation. Low anal resting pressures are frequently observed in patients with prolapse and may be caused by continuous rectoanal inhibition, or by the dilating effect of the pro- lapse itself, with or without pudendal neuropathy. However, others feel that an initial increase in external sphincter tone may cause a cycle of outlet obstruction, constipation, and straining. An impaired tolerance to dis- tention, with reduced compliance and tone, may con- tribute to incontinence. Obviously it is difficult to determine which physiologic alterations are direct etio- logic factors and which are secondary to the progressive prolapse of the rectum, especially a reduced internal sphincter pressure. Internal intussusception, also called internal or hidden prolapse, occurs when the prolapse does not protrude through the anal orifice. Mucosal prolapse is diagnosed when the mucosa slides on the submucosa and protrudes through the anal canal. It is generally treated along the lines of hemorrhoidal disease. ■ CLINICAL FEATURES Except when occurring in infants or the senile elderly patient, the patient is immediately aware of the prolapse. Prolapse initially occurs only with defecation and strain- ing. Later as the tissues become more lax, the rectum may prolapse with the mildest straining, or even when the patient stands up. Tenesmus, bleeding, and mucus dis- charge are associated symptoms. Incontinence may range from mucus leakage to complete fecal incontinence. A his- tory of bladder and gynecologic dysfunction and prolapse should be sought in appropriate cases. On examination, the anus may be patulous. Visualization of everted bowel with concentric folds allows definitive diagnosis. If prolapse is not evident, the patient should be examined while straining on the commode. The left lateral and jack-knife positions are frequently inadequate to reproduce the prolapse, and more important, they are inadequate to rule out a diagnosis of prolapse. Occasionally the prolapse is incarcerated and requires the application of hypertonic sugar or honey to allow shrinkage and reduc- tion. If a small prolapse is difficult to distinguish from hem- orrhoids, the index finger should be introduced to display the sulcus between the layers of prolapsed bowel. As well as confirming the diagnosis of prolapse, exam- ination is performed to check for an anterior enterocele or rectocele. The sphincters are carefully examined. Proctosigmoidoscopy is the minimum requirement to look at the mucosa and evaluate for a lead point or other pathologic change. The majority of patients have already been examined by colonoscopy because of their age and the presence of rectal bleeding that is associated with their presentation. The diagnosis of rectal prolapse is usually straightfor- ward, but hemorrhoids, prolapsing polyps, and anorectal neoplasia must be excluded. Conditions such as solitary rectal ulcer and colitis cystica profunda may present with similar symptoms, but may also coexist in the patient with prolapse. Some authors advocate evaluating transit time in those with constipation. We do not do this routinely, but only in those with a history of severe constipation and associated sphincter weakness, in order to get evidence to avoid colectomy in patients without definite slow transit. Those with chronic straining at stool should have evaluation for paradoxic contraction of the anal sphincters, or anismus, so that biofeedback therapy may be instituted prior to repair of the prolapse. The clinical and cost benefit of rou- tine preoperative studies, including anal manometry, pudendal nerve terminal motor latency, colonic transit studies, and defecography is unclear. ■ PREOPERATIVE CONSIDERATIONS The general health of the patient is of great importance in preoperative decision making. The elderly with extremely poor health may be more suitable for a perineal approach. However, increasing experience with the laparoscopic
Transcript of Current Therapy in Colon and Rectal Surgery Volume 7435 || RECTAL PROLAPSE
23-
RECTAL PROLAPSEConor P. Delaney, MD, MCh, PhD,
FRCSI (Gen), FACSAnthony J. Senagore, MD, MBA, MS, FACS
-Rectal prolapse occurs when the full thickness of the rec-tal wall protrudes through the anal canal. The condition ismost commonly seen in older females, but may occur inboth sexes and at any age. Although rectal prolapse hasfascinated surgeons for many years, the optimal surgicalapproach has not been determined. Over 100 surgicaloperations have been reported, and these procedures canbe grouped into perineal and abdominal approaches.Choosing the optimal repair for an individual patientinvolves consideration of many factors, including thepatient’s general health and whether there is a history ofconstipation (present in 25 to 50%) or fecal incontinence(present in approximately 75%).
■ PATHOPHYSIOLOGY
The mechanisms by which prolapse occur remain poorlyunderstood. Broden and Snellman suggested that pro-lapse is initiated by a midrectal intussusception, whichcommences 8 to 10 cm inside the rectum. One initiatingfactor may be chronic straining, which might explain theassociation with colitis cystica profunda and solitary rec-tal ulcer. Prolapse is also thought to be related to abnor-mal intestinal motility, such as is seen in slow-transitconstipation.
Low anal resting pressures are frequently observed inpatients with prolapse and may be caused by continuousrectoanal inhibition, or by the dilating effect of the pro-lapse itself, with or without pudendal neuropathy.However, others feel that an initial increase in externalsphincter tone may cause a cycle of outlet obstruction,constipation, and straining. An impaired tolerance to dis-tention, with reduced compliance and tone, may con-tribute to incontinence. Obviously it is difficult todetermine which physiologic alterations are direct etio-logic factors and which are secondary to the progressiveprolapse of the rectum, especially a reduced internalsphincter pressure.
Internal intussusception, also called internal or hiddenprolapse, occurs when the prolapse does not protrudethrough the anal orifice. Mucosal prolapse is diagnosedwhen the mucosa slides on the submucosa and protrudesthrough the anal canal. It is generally treated along thelines of hemorrhoidal disease.
■ CLINICAL FEATURES
Except when occurring in infants or the senile elderlypatient, the patient is immediately aware of the prolapse.Prolapse initially occurs only with defecation and strain-ing. Later as the tissues become more lax, the rectum mayprolapse with the mildest straining, or even when thepatient stands up. Tenesmus, bleeding, and mucus dis-charge are associated symptoms. Incontinence may rangefrom mucus leakage to complete fecal incontinence. A his-tory of bladder and gynecologic dysfunction and prolapseshould be sought in appropriate cases.
On examination, the anus may be patulous.Visualization of everted bowel with concentric folds allowsdefinitive diagnosis. If prolapse is not evident, the patientshould be examined while straining on the commode. Theleft lateral and jack-knife positions are frequently inadequateto reproduce the prolapse, and more important, they areinadequate to rule out a diagnosis of prolapse. Occasionallythe prolapse is incarcerated and requires the application ofhypertonic sugar or honey to allow shrinkage and reduc-tion. If a small prolapse is difficult to distinguish from hem-orrhoids, the index finger should be introduced to displaythe sulcus between the layers of prolapsed bowel.
As well as confirming the diagnosis of prolapse, exam-ination is performed to check for an anterior enteroceleor rectocele. The sphincters are carefully examined.Proctosigmoidoscopy is the minimum requirement tolook at the mucosa and evaluate for a lead point or otherpathologic change. The majority of patients have alreadybeen examined by colonoscopy because of their age andthe presence of rectal bleeding that is associated with theirpresentation.
The diagnosis of rectal prolapse is usually straightfor-ward, but hemorrhoids, prolapsing polyps, and anorectalneoplasia must be excluded. Conditions such as solitaryrectal ulcer and colitis cystica profunda may present withsimilar symptoms, but may also coexist in the patient withprolapse.
Some authors advocate evaluating transit time in thosewith constipation. We do not do this routinely, but only inthose with a history of severe constipation and associatedsphincter weakness, in order to get evidence to avoidcolectomy in patients without definite slow transit. Thosewith chronic straining at stool should have evaluation forparadoxic contraction of the anal sphincters, or anismus,so that biofeedback therapy may be instituted prior torepair of the prolapse. The clinical and cost benefit of rou-tine preoperative studies, including anal manometry,pudendal nerve terminal motor latency, colonic transitstudies, and defecography is unclear.
■ PREOPERATIVECONSIDERATIONS
The general health of the patient is of great importance inpreoperative decision making. The elderly with extremelypoor health may be more suitable for a perineal approach.However, increasing experience with the laparoscopic
