Class 14: Anus, Rectum and Prostate

Anal canal

Approx 3.8 cm long . This canal is surrounded by two layers of muscles called sphincters. Contains an internal and external sphincter

Internal sphincter

Under autonomic nervous system control

External sphincter

Wraps around the internal sphincter and is under voluntary control

What do the sphincters do?

Keep anus tightly closed

Anal columns

folds in the mucosa and each column has an artery and  vein

Hemorrhoid

• When there is increased pressure in the anal columns and the vein becomes engorged with blood

• Small grape like sacs

Rectum

distal position of the large intestine and is 12 cm long. It starts at the sigmoid colon and extends to the anal canal

Prostate gland

lies in front of the rectum and 2 cm behind the symphysis pubis.

It surrounds the bladder neck and the urethra and has 15-30 ducts opening into the urethra.

Its job is to secrete a fluid and semen that contains sperm

Seminal vesicles

secrete a fluid important for nourishment of sperm and fluid that will eventually become sperm

The bulbourethral glands (aka Cowper’s glands)

inferior to the prostate on either side of the urethra and their job is to secrete a fluid that neutralizes the acidity in the urethra that would be harmful to sperm

Combined length of anal canal and rectum in adults

16 cm

Benign prostate hypertrophy

The prostate gradually increases in men at around age 40

This eventually impeded urine flow by obstructing the urethra

Subjective data

1. Usual bowel routine

2. Change in bowel habits

3. Rectal bleeding, blood in the stool

4. Medications

• Laxatives, stool softners, iron

5. Rectal conditions

• Pruritus, hemorrhoids, fissure, fistula

6. Family history

7. Self-care behaviours

• diet of higher fibre foods, most recent examinations

Recommendations for screening

• • Canadian Cancer Society (2016) recommends screening for men and women aged 50+ years every 2 years

  • People at high risk can be screened at an earlier age

  • Fecal occult blood test (FOBT)

  • Positive FOBT may be followed up with colonoscopy, sigmoidoscopy, double-contrast barium enema

Risk factors for prostate cancer

–Most common cancer in canadian men

—Age >65 years

–Family history

–Diet high in fat

–African ancestry

Screening

–Discuss risks and benefits of testing with men age 50 years and older

–DRE (digital rectal examination)

–PSA (prostate-specific antigen)

•Canadian Cancer Society, 2016

Rectal examination positions

Left lateral, lithotomy, or standing position

Inspection

• Perianal area

• Skin

  • The anus is usually it is moist and hairless with coarse folded skin that is more pigmented than the perianal skin

• Anal opening

  • normally tightly closed. Take note of any inflammation, lesions, splits, protrusions, or scars

• Sacrococcygeal area

• Valsalva manoeuvre

  • Ask the patient to bear down (perform the valsalva maneuver) – there should be no break in skin integrity

Inspection abnormalities

• Pilonidal cyst or sinus

• Anorectal fistula

• Fissure

• Hemorrhoids

• Rectal prolapse

• Pruritis ani

Rectal prolapse

when part of the mucous membrane of the rectum protrudes out through the anal opening and almost appears like a little red donut

Pruritis ani

intense perianal itching and burning with reddened, thickened skin around the anus