Perioperative management - Transanal mucosal resection according to Rehn-Delorme

• External full-thickness rectal prolapse (Grade III) in patients for whom an abdominal procedure should be avoided (high-risk patients).
• Internal rectal prolapse (intussusception) as part of an obstructive defecation syndrome (ODS) with very critical indication by an experienced colorectal surgeon.

• relative contraindication with large prolapse
• general inoperability
• lack of suffering pressure

History
Does the prolapse occur only during defecation and physical exertion, or is it persistent?
Perianal bleeding is often reported, e.g., due to a simple rectal ulcer (benign, common in rectal prolapse, always located anteriorly).
Is there constipation or diarrhea, possibly alternating?
Other complaints include the feeling of incomplete evacuation (= repetitive toilet visits with intense, frustrating straining), tenesmus, and mucus discharge.
Almost always, there is fecal incontinence with social impairments: For example, a toilet must always be nearby, fasting period before leaving the house.
In women, there is often a concurrent pelvic floor descent with urinary incontinence.

Proctological Basic Examination with inspection,
palpation, and proctorectoscopy

• Inspection/Straining Test: As impressive as an advanced rectal prolapse may be, it can be easily overlooked if it only occurs during defecation and the patient avoids strong straining during the examination out of embarrassment or – which is not uncommon – confuses straining with squeezing. The prolapse often appears only after several straining attempts. If necessary, examination in a squatting position or on the toilet chair. Circular mucosal folds are typical for complete rectal prolapse.

• Digital Rectal Examination: Active contraction or relaxation allows a rough assessment of the sphincter apparatus. During straining, an intussusception or rectocele may be palpable. Induration of mucosal areas: Could indicate a simple rectal ulcer.

• Proctoscopy: Intussusception is often (not always) recognizable by a bulging of the ventral rectal wall through the anal canal when the proctoscope is withdrawn to the outer end of the anal canal and the patient is asked to strain.

• Rectoscopy: Can show a simple rectal ulcer (always located anteriorly).
  A distal proctitis beginning at the anorectal junction and abruptly ending at 10-12 cm from the anus is often accompanied by a rectal prolapse.

Functional Diagnostics

Defecography can confirm a prolapse; if the diagnosis is clear, it can be omitted.

• Conventional Defecography
  Besides rectal prolapse, changes such as rectocele, intussusception, and sigmoidocele can be assessed by conventional defecography. Since defecography can diagnostically differentiate both functional and morphological changes of the pelvic floor, including the rectosigmoid – with oral contrast also enteroceles – it is a highly informative examination, especially in pelvic floor insufficiency with the leading symptom "evacuation disorder."
  Due to the multifactorial etiology of pelvic floor insufficiency involving usually several compartments and often combined disorders, the dynamic imaging of all pelvic organs is crucial.
  Changes in the middle "gynecological" compartment and the anterior "urological" compartment of the pelvic floor cannot be imaged. This was previously only indirectly possible through additional contrast of accessible organs using colpocystography, where the radiation exposure and psychological stress of the examination itself should not be neglected.

• Dynamic Pelvic Floor MRI
  Dynamic pelvic floor MRI, compared to conventional defecography, provides the possibility of a complete depiction of the pelvic floor and its organs, as it can display the anterior, middle, and posterior compartments and additionally enteroceles without radiation exposure. Dynamic pelvic floor MRI
  can simultaneously depict the anatomical position of all pelvic organs during breathing, straining, and squeezing phases both in single images and in video sequences with high informational value.
  In general, dynamic pelvic floor MRI (as MR defecography) offers the advantage of dynamic imaging of all compartments or organ systems with improved patient comfort compared to conventional defecography, especially in typically female patients.
  The main advantages lie in the absence of radiation exposure. Sitting and lying examination positions do not lead to different results. However, the image morphological relevance of dynamic MRI examination is not yet fully clarified, as normal and pathological findings overlap.

• In case of suspected sphincter defect, Endosonography is helpful.

• Additional functional tests such as Electromyography and nerve conduction velocity measurement are reserved for exceptional cases.

Colonoscopy
Preoperative standard for examining colorectal topography and excluding other pathologies.

• For bowel preparation, a simple enema treatment the evening before the operation and on the morning of the operation day is sufficient.

• Orthograde bowel lavage optional

In the operating room:

• Perioperative antibiotic prophylaxis as a single shot with 1.5-3.0 g ampicillin/sulbactam i.v.
• Indwelling urinary catheter

General Risks

• Bleeding
• Rebleeding
• Need for transfusions with associated transfusion risks
• Thromboembolism
• Wound infection
• Abscess
• Injury to adjacent organs/structures (internal genitalia in women, bladder)

Specific Risks

• Abscess formation
• Change in bowel habits
• Recurrent prolapse
• Persistent fecal incontinence or residual incontinence
• Supranal rectal stenosis