Fiser Chapter 37 ANAL AND RECTAL Flashcards
Thrombosed external hemorrhoid tx
< 72 hours: elliptical excision to relieve pain (can also use elliptical excision to resect external hemorrhoids)
> 72 hours: lance open
Surgical tx of anal fissure
Lateral subcutaneous internal sphincterotomy
Complication: fecal incontinence
Do NOT perform if d/t Crohn’s or UC
Rectal prolapse
Starts 6-7 cm from anal verge, involves all layers of rectum
Etiology: pudendal neuropathy and laxity of anal sphincters
Risk factors: Female, straining, chronic diarrhea, previous pregnancy, and redundant sigmoid
Tx: High-fiber diet, surgery (Altemeier or LAR)
Tx of anal canal adenocarcinoma
Usually APR, Postop chemoXRT (same as rectal cancer)
WLE if <3cm, <1/3 circumference, limited to submucosa (T1 tumors, 2-3 mm margin needed), well-differentiated, no lymphovascular invasion; needs about 1 cm margin
Etiologies of anal incontinence
Neurogenic (gaping hole): no good tx
Abdominoperineal descent: chronic damage to levator ani muscle and pudendal nerves (obesity, multiparity) and anus falls below levators; Tx high fiber diet, limit to 1 BM a day, hard to tx!
Obstetrical trauma: Tx anterior anal sphincteroplasty
Ulcerating, slow growing anal margin lesion
Anal margin squamous cell cancer
Men have better prognosis
Metastasizes to inguinal nodes
Tx: WLE for <5cm (need 0.5 cm margin)
>5 cm or involving sphincter or positive nodes, Chemo-XRT (5-FU and cisplatin), trying to preserve sphincter and avoid APR; inguinal node dissection if clinically positive
Anal canal lesion with pruritis, bleeding, and palpable mass
Squamous cell CA (e.g. epidermoid CA, mucoepidermoid CA, cloacogenic CA, basaloid CA)
-Tx: Nigro protocol (chemo-XRT with 5-FU and mitomycin), NOT surgery; cures 80%; APRT for tx failure or recurrence
Anal canal versus anal margin squamous cell cancer
Margin (below dentate line) better prognosis
Surgical tx of rectal prolapse
Perineal rectosigmoid resection (Altemeier) transanally if patient old and frail
LAR and pexy of residual colon if good condition patient
Anus blood supply
Inferior rectal artery
Internal hemorrhoid plexus (above dentate line) and external hemorrhoid plexus (below dentate line)
Anal margin central ulcer with raised edges
Basal cell CA
Rare mets
Tx: WLE usually sufficient (3 mm margins, rarely need APR unless sphincter involved)
AIDS patient presents with RLQ pain, fever, with shallow anorectal ulcers
CMV: similar presentation as appendicitis, tx Ganciclovir
1 rectal ulcer etiology
HSV, can see in AIDS patients
Nigro protocol
Anal canal SqCC: Chemo-XRT, 5-FU, mitomycin
Anal margin SqCC: Chemo-XRT, 5-FU, cisplatin
Tx of anal canal melanoma characteristics and tx
Is 3rd most common site (1. skin, 2. eyes, 3, anal canal)
1/3 has mesenteric LN spread; if symptomatic, often significantly metastatic
Hematogenous spread to liver and lungy is early and accounts for most deaths
Most common symptom rectal bleeding
Most tumors lightly pigmented or not at all
Tx: Usually APR, margin dictated by depth of lesion (standard for melanoma)
Hemorrhoids tx
Fiber
Stool softeners
Sitz baths
AIDS patient with anal nodule and ulceration
Kaposi’s sarcoma, most common cancer in AIDS patients
Internal hemorrhoid surgical tx
Primary and secondary can be banded
Tertiary and quaternary: 3-quadrant resection
-Resect down to internal anal sphincter (but NOT through)
Do NOT band external hemorrhoids (painful)
Difference between internal and external hemorrhoids
- Internal hemorrhoids: cause bleeding or prolapse
- Primary: slides below dentate with strain
- Secondary: prolapses but reduces spontaneously
- Tertiary: must be manually reduced
- Quaternany: unable to reduce
- External hemorrhoids: distal to dentate line, covered by sensate squamous epithelium, can cause pain/swelling/itching, especially when thrombosed
Surgical indications for hemorrhoids
Recurrence
Thrombosis multiple times
Large external component
Anal margin (below dentate line) lesions
Squamous cell CA
Basal cell CA
Pilonidal cyst
Sinus or abscess formation over sacrococcygeal junction, increased in men
Tx: Drain and pack, follow-up surgical resection of cyst
Anal cancer associated with what
HPV
XRT
Fistula-en-ano tx
- Often occurs after anorectal abscess
- Do NOT need to excise tract
Tx:
Upper 2/3 of external anal sphincter -> rectal advancement flap (incontinence most worrisome complication)
Lower 1/3 of external anal sphincter -> fustulotomy (open tract up, curettage out, let heal by secondary intention)
Anal fissure
Split in anoderm (90% in posterior midline) -> pain and bleeding after defecation -> if chronic will see a sentinel pile
Medical tx: sitz baths, bulk, lidocaine jelly, stool softeners (90% heal)
Surgery: lateral subcutaneous internal sphincterotomy (do NOT perform if d/t Crohn’s or UC; higher suspicion if lateral or recurrent fissures)
Anorectal abscess
Antibiotics for cellulitis, DM, immunosuppressed, or prosthetic hardware
- Perianal, intersphincteric, or ischiorectal: drain through skin, since are below levator muscles
- intersphincteric and ischiorectal abscesses can form horseshoe abscess
- Supralevator abscess: must drain transrectally
Anal canal and margin
Canal above dentate line
Margin below dentate line
Why is fistulotomy NOT used for fistulas in upper 2/3 of external anal sphincter?
Risk of incontinence
Simple and complex rectovaginal fistulas
Simple (low to mid-vagina)
Tx: Trans-anal rectal mucosa advancement flap
Many obstetrical fistulas heal spontaneously
Complex (high in vagina):
-Tx: abdominal or combines abdominal and perineal approach usual; resection and re-anastomosis of rectum, close hole in vagina, interpose omentum, temporary ileostomy
AIDS patients with anorectal ulcer
Kaposi’s sarcoma
CMV (similar presentation as appendicitis)
HSV (#1 rectal ulcer)
B cell lymphoma (can look like abscess or ulcer)
-Need to biopsy these ulcers to r/o cancer and differentiate problems
Hemorrhoidal plexuses
Left later, right anterior, right posterior
Anorectal nodal mets
Superior and middle rectum -> IMA nodes
Lower rectum -> Primarily IMA nodes, but also internal iliac nodes
Upper 2/3 anal canal -> internal iliac nodes
Lower 1/3 anal canal -> inguinal nodes
Goodsall’s rule
Anterior fistulas connect with anus/rectum in a STRAIGHT line
Posterior fistulas go toward a midline internal opening in the anus/rectum
Anal canal (above dentate line) lesions
Squamous cell CA (e.g. epidermoid CA, mucoepidermoid CA, cloacogenic CA, basaloid CA)
Adenocarcinoma
Melanoma
Condylomata acuminata
Cauliflower mass
HPV papillomavirus
Tx: laser surgery
