Rectal prolapse
The case
A 55-year-old man presents with a painful anorectal mass. He reports a history of chronic constipation and hemorrhoids, and frequently strains to have a bowel movement. He states that, while straining about 2 hours prior, he felt "something come out" and was unable to "push it back in." He denies any previous abdominal or anorectal surgeries.
Vital signs are as follows: T 98.8 F, HR 99, BP 140/90, RR 18, SpO2 100% on room air
On physical examination, the patient is lying on his right side and appears uncomfortable due to pain. Heart and lung exams are unremarkable. Abdomen exhibits normal bowel sounds and is soft and non-tender. External anal exam reveals a pink edematous complete prolapse of about 4 centimeters of rectum. The surrounding anal area had multiple external non-thrombosed hemorrhoids.
After applying lidocaine jelly to the area, you apply gentle manual internal pressure to the prolapsed bowel. However, the patient reports significant pain with this and asks you to stop the procedure.
The brush up
Rectal prolapse, while uncommon, is typically a disease of older women, regardless of parity; however, it can happen to anyone. It almost always occurs as a result of increased intra-abdominal pressure.
There are 3 types of rectal prolapse: complete, mucosal, and incomplete. Consider prolapsed internal hemorrhoids in your differential as well. Externally, you can distinguish complete (A) and mucosal (B) rectal prolapses by the presence of concentric vs radially oriented tissue folds, respectively:
An incomplete prolapse (A) may only be detected on digital rectal examination, depending on proximity to the anal verge (B demonstrates complete prolapse):
Only attempt to manually reduce a viable rectal prolapse (the tissue should be pink; any dusky or necrotic tissue requires urgent surgical consultation). Reduction involves applying gentle but continuous pressure on the medial luminal surface while rolling the tissue internally with both thumbs. It is easiest to perform with the patient in the dorsal lithotomy or prone knee-chest position:
For a large or edematous prolapse, you can apply up to a half cup of table sugar (sucrose, NOT a sugar substitute) as an osmotic agent to aid reduction. It is not known what, if any, effect this has on the patient's serum glucose measurement.
The conclusion
The patient underwent successful manual reduction after sucrose desiccation. He tolerated the procedure well and a subsequent digital rectal exam was normal. He was discharged home to follow up with general surgery the following day, and was prescribed stool softeners and home care instructions including a high fiber diet, increased water intake, and avoidance of straining.
References
Varma MG and Steele SR. Overview of rectal procidentia (prolapse). In: UpToDate, Weiser M and Chen W (Eds), UpToDate, Waltham, MA, 2017.
https://commons.wikimedia.org/wiki/File:Full_thickness_rectal_prolapse_%26_mucosal_prolapse..jpg
https://commons.wikimedia.org/wiki/File:Internalrectalintussusceptionexternalrectalprolapse.JPG
https://www.flickr.com/photos/internetarchivebookimages/14781546371
Coburn WM, Russell MA, Hofstetter WL. Sucrose as an aid to manual reduction of incarcerated rectal prolapse. Ann Emerg Med 1997 Sep;30(3):347-9.