Читать книгу Small Animal Surgical Emergencies - Группа авторов - Страница 198

Evaluation of patients with rectal prolapse begins with a thorough medical history which frequently includes signs such as tenesmus, diarrhea, constipation, or stranguria. Additional required information should include diet, deworming history, concurrent medical problems, and current medications. This information is integral to determining a primary cause for the prolapse [5].

A thorough physical exam will readily lead to a diagnosis of rectal prolapse. Rectal prolapse is considered to be partial when only the rectal mucosa protrudes from the anus whereas a complete prolapse occurs when all layers of rectum are protruding through the anal orifice [6, 7]. A digital rectal exam is a critical part of the physical but may be impossible in more severely affected patients at the time of presentation. Additionally, a complete prolapse must be differentiated from a prolapsed intussusception which is a surgical emergency. To differentiate the two conditions, the clinician should pass a blunt, lubricated instrument or thermometer between the prolapsed tissue and the anal wall. The instrument tip cannot be advanced due to the presence of the fornix between the rectum and the anus in cases of rectal prolapse (Figure 7.1) [5].

Depending on the underlying cause of the prolapse, patients may present dehydrated, hypovolemic, hypotensive, tachycardic, painful, and exhibiting other signs consistent with shock. These patients should be stabilized with intravenous fluids and pain medications prior to pursuing additional diagnostics or treatment. In many cases, patients are relatively stable, even when suffering with large, complete prolapses. The affected tissues can exhibit severe edema, swelling, and congestion. Viability of the prolapsed tissues must be determined; evidence of significant trauma or necrosis are both indications for urgent surgical intervention for rectal resection and anastomosis.

Diagnostics should be tailored toward each patient based on the history and physical exam findings. At a minimum, fecal flotation, fecal culture, complete blood count, serum chemistry, urinalysis with or without urine culture, and abdominal radiography or ultrasonography should be recommended. Abdominal computed tomography, thoracic radiographs, and endoscopic imaging and biopsies can also be considered, especially in cases of recurrent prolapse or when a neoplastic process is suspected.