Perioperative management - STARR procedure

Transanal stapled rectal resection (STARR, “stapled transanal rectal resection”) has established itself as a surgical option for the treatment of obstructive defecation syndrome (ODS; synonym: outlet obstruction). The STARR method aims to reduce rectal intussusception (= internal rectal prolapse) and/or rectocele as morphological causes of outlet obstruction by combining a transverse tightening of the rectovaginal septum through the staple line with circular rectal mucosal resection.

Obstructive defecation in the sense of outlet obstruction is a form of chronic constipation. It is a pathology with high incidence that significantly restricts the quality of life of many people.

The causes are varied: On the one hand, stenoses in the anal and lower rectal area can cause defecation disorders. On the other hand, functional disorders of the pelvic floor structure are found.

Pelvic floor dyssynergia, i.e., a paradoxical contraction of the puborectalis muscle and the anal sphincter during defecation, and anismus (involuntary, uncontrollable, spontaneous contraction of the pelvic floor musculature) are considered the most important functional causes.
Common morphological changes in the pelvic floor in defecation disorders are rectoceles, distal rectal intussusception, and enteroceles/sigmoidoceles (prolapse of small bowel segments or the sigmoid into the deep Douglas pouch, especially after hysterectomy and in the context of general prolapse issues). Rectocele and intussusception are held responsible for mechanical closure.
Enterocele/sigmoidocele and genital prolapse are possible extrarectal causes. Stool retention in the sagging sigmoid colon (cul de sac) or compression of the rectum by the bowel loop can lead to defecation disorders.
The clinical significance of the various morphological anomalies has not yet been fully clarified.

Since correction of the morphological changes does not necessarily lead to an improvement in function, surgical intervention should only be considered after failure or ineffectiveness of conservative measures.

• Slow-transit constipation with hypo- or aganglionosis
• Functional outlet obstruction, e.g., paradoxical puborectalis syndrome, anismus
• Pathology of the sigmoid colon (diverticulitis, pronounced sigmoidocele) → rel. contraindication, here a laparoscopic sigmoid resection with ventral or dorsal rectopexy should be performed.
• Anal fissure
• Anal stenosis
• Fistulas
• Inflammatory bowel diseases in the rectum such as IBD, proctitis
• Tumor diseases in the rectum
• Previous operations in the pelvis, especially status post rectum resection
• Foreign material from previous operations (e.g., indwelling mesh after rectopexy or gynecological previous operation)

Pelvic floor diagnostics begin after the exclusion of pathological changes such as chronic anal fissure, possibly with consecutive anal stenosis, prolapsing hemorrhoidal disease, anal prolapse, manifest rectal prolapse, through proctological basic diagnostics.
Stenoses of the colon and rectum due to malignancies or a chronic inflammatory bowel disease must of course be clarified in the context of primary diagnostics. Therefore, a total colonoscopy is required in all patients with defecation disorders. After exclusion of these changes that need to be treated primarily, the medical history provides the most important information about the present complaint picture.

Medical history using standardized questionnaires to assess constipation or incontinence. The typical symptomatology consists of delayed and incomplete bowel emptying, a feeling of blockage, excessive straining during defecation, digital support of emptying, fecal smearing (often evaluated as incontinence for soft stool), use of laxatives, and anal bleeding.

To differentiate from irritable bowel syndrome with an obstructive component, further complaints should be inquired about, especially abdominal pain and meteorism. Urological and gynecological complaints should also be checked. They are often together a sign of a complex organ descent.

Clinical proctological examination with inspection, rectal-digital examination, proctoscopy and rectoscopy, total colonoscopy, CT of the abdomen in case of pronounced pain symptoms during defecation as an indirect indication of sigma pathology, functional diagnostics. The most important examination is the radiological representation of the emptying process.

Conventional Defecography:

Besides rectal prolapse, changes such as rectocele, intussusception, and sigmoidocele can be assessed by conventional defecography. Since defecography can differentially diagnose both functional and morphological changes of the pelvic floor including the rectosigmoid – with oral contrast administration also enteroceles – it is especially an examination with high informative value in pelvic floor insufficiency with the leading symptom “emptying disorder”.
Due to the multifactorial etiology of pelvic floor insufficiency with involvement of usually several compartments and often combined disorders, the dynamic imaging of all pelvic organs is crucial.
Changes in the middle “gynecological” compartment and in the anterior “urological” compartment of the pelvic floor cannot be imaged. This was only possible indirectly in the past through additional contrasting of the accessible organs using colpocystorectography, whereby the radiation exposure and the psychological burdens from the examination itself must not be neglected.

Dynamic Pelvic Floor MRI:

The dynamic pelvic floor MRI has the possibility, compared to conventional defecography, to ensure a complete representation of the pelvic floor and its organs, since with one examination pass the anterior, middle, and posterior compartments and additionally enteroceles can be depicted without radiation exposure.
Seated and lying examination positions do not lead to different results. However, in general, the image-morphological relevance of the dynamic MRI examination has not yet been fully clarified, as normal and pathological findings overlap.

Ultrasound as Dynamic Perineal or Endorectal Ultrasound:

Recommended as a non-invasive examination, especially if no dynamic MRI is available. The quite simple examination can provide additional information on pelvic floor pathologies, among others enterocele, rectocele, and cystocele.

Colon Transit Time:

The performance of a transit examination (Hinton test) is only indicated in case of anamnestic suspicion of a transport disorder with significantly reduced defecation frequency.

• For bowel preparation, a simple enema treatment on the evening before the operation as well as on the morning of the operation day is sufficient.
• Perioperative antibiotic prophylaxis (and if necessary, in individual cases also short-term therapy) with a 2nd generation cephalosporin and metronidazole i.v. or ampicillin/sulbactam i.v..

• When establishing the indication and during patient informed consent, the relatively high complication rate must be taken into account.
• Postoperative bleeding
• septic complications
• imperative urge to defecate
• urinary retention
• staple line insufficiency
• fecal incontinence
• Recurrence of the intussusception and/or of the obstructive defecation syndrome
• Rectovaginal fistula