- prolapse is protrusion of a portion of the rectum or rectal mucosa through the anus, usually caused by an underlying disorder. Just about any gastrointestinal (enteritis ) or urogenital condition (dystocia, urethral calculus [Ureter: urolithiasis] ) that causes tenesmus can result in rectal prolapse. The problem is most commonly seen in young dogs afflicted with endoparasitism. Laxity of the anal sphincter or perianal connective tissue (perineal hernia with rectal sacculation) may also predispose small animals to this condition. It is critical for the surgeon to be aware of predisposing cause(s) because the success of the surgery often correlates with proper treatment of the primary cause of tenesmus. (Figs. 1-2)
- There are three surgical techniques designed to treat/prevent rectal prolapse (perianal pursestring suture, colopexy, and rectal resection). The choice of technique depends on the underlying condition (whether it can be successfully treated and if it is recurrent or not) and on the viability of the prolapsed tissue.
- A thorough physical and rectal examination should be performed. Additional diagnostics such as fecal analysis , complete blood count , chemistry panel, urinalysis and culture , abdominal and thoracic imaging may be required. It is critical that the primary cause of the prolapse be identified and treated.
- Rectal prolapse must be differentiated from intussusception . The latter must be approached from the abdomen for treatment. Insert a finger or probe alongside the prolapse: if the probe can be inserted cranially more than a few centimeters, the condition is an intussusception.
- Treatment of the prolapse should be prompt to reduce further trauma. Extensive colorectal preoperative preparation is often not necessary.
- Pursestring sutures are relatively quick and easy to perform with little risk of complications. Since this is the least expensive and least invasive technique, it is usually chosen first when the condition causing the tenesmus is expected to be eradicated with medical therapy.
- Colopexy requires an invasive midline laparotomy , but the technique is readily performed, with little additional risk to the patient.
- Rectal resection is performed outside the patients body to excise diseased tissue, so contamination of sterile tissues during surgery is minimized. Rectal resection has the advantage of removing the diseased portion of the rectum and additionally it eliminates redundant rectum, thereby decreasing the risk of re-prolapse. There is more danger of serious complications with this technique so it is performed only when absolutely necessary and with owners full understanding about the risks.
- Pursestring sutures are often unsuccessful unless the condition causing the problem is readily treatable, and tenesmus can be controlled.
- Colopexy is an invasive treatment, and recurrence may occur if the cause of the tenesmus is not controlled.
- Rectal resection has several serious postoperative complications, such as stricture formation , incontinence, and dehiscence which may be life-threatening.
- General surgery pack of instruments.
- Balfour retractors to help with exposure during colopexy.
- Suture material (see technique below for suggestions).
- 4x4 sponges.
- Draping and laparotomy pads for the colopexy.
- Pursestring : reduction is usually completed within 10 minutes. Skin preparation, 5 minutes.
- Colopexy : abdominal skin preparation, 10 minutes.
- Rectal resection : lavage and cleansing of prolapse, 10 minutes.
- The prognosis after surgery with all techniques is generally good provided the primary cause of the prolapse has been managed successfully, straining is controlled, and the appropriate surgical procedure was performed correctly.
- For example, in a young patient with endoparasites, successful treatment of the parasite and temporary pursestring suture of a viable prolapse is usually curative. On the other hand, a dog with permanent anal laxity following anorectal surgery (which is usually untreatable and permanent), the prognosis is guarded at best since recurrence is likely.
Reasons for treatment failure
- Wrong choice of procedure for condition, failure to treat primary cause of the prolapse, failure to manage straining after surgery, poor technique.