Structure and Function: Anal Canal
-Outlet of gastrointestinal -
tract; lined with modified skin;
no hair or sebaceous glands
-Contains only autonomic
nerves, but numerous somatic
sensory nerves present in
anal canal and external skin,
so one feels sharp pain with
trauma to anal area
-Surr
Structure and Function: Anal Canal
Under voluntary control; except for passing feces and gas, sphincters keep anal canal tightly closed
Intersphincteric groove separates internal and external sphincters and is palpable
Anal columns, or columns of Morgagni, are folds of mucosa; extend verti
Structure and Function: Rectum
Rectum is distal portion of large intestine
It extends from sigmoid colon, at level of third sacral vertebra, and ends at anal canal
Just above anal canal, rectum dilates and turns posteriorly, forming rectal ampulla
-Rectal interior has three
semilunar t
Structure and Function: Peritoneal Reflection
Peritoneum covers only upper two thirds of rectum
In male, anterior part of peritoneum reflects down to anal opening, forming rectovesical pouch and then covers bladder
In female, it is termed the rectouterine pouch
Prostate Gland
-Lies in front of anterior wall
of rectum and 2 cm behind
symphysis pubis
-Surrounds bladder neck and
urethra and has 15 to 30 ducts
that open into urethra
-Two seminal vesicles project
above prostate
-Secrete a fluid rich in
fructose, which nourishes
spe
Regional Structures
-Uterine cervix, in females, lies
in front of anterior rectal wall
and may be palpated through
it
-Combined length of anal
canal and rectum is about 16
cm in adult
-Sigmoid colon, S-shaped
course in pelvic cavity
-Extends from iliac flexure of
descending
Children and adults
At male puberty, prostate gland undergoes a very rapid increase to more than twice its prepubertal size; during young adulthood size remains fairly constant
Prostate gland commonly starts to enlarge during middle adult years; increases with age
Thought th
Culture and Genetics: Prostate Cancer
-More common in North
America and northwestern
Europe; less common in
Central and South Americas,
Africa, and Asia
Incidence higher for black men than other racial groups, and more likely to be diagnosed at advanced stage
Mortality rates are two times hig
Prostate cancer
Screening recommendations vary for racial groups
Men at high risk, black men, and men with first-degree relative with disease should begin screening at age 45
Colorectal cancer also has racial variation
Incidence in black women and men is almost 20% higher than in white women and men
Mortality is 50% higher in black men and women than in white men and women
Rectal conditions
pruritus, hemorrhoids, fissure, fistula
Position for exams
Examine male in left lateral decubitus or standing position; instruct standing male to point his toes together; this relaxes regional muscles, making it easier to spread buttocks
Place female in lithotomy position if examining genitalia as well
Use left l
Inspect Perianal Area
Spread buttocks wide apart, and inspect perianal region
Anus normally looks moist and hairless, with coarse folded skin more pigmented than perianal skin
Anal opening tightly closed; no lesions present
Inspect sacrococcygeal area; normally appears smooth
Palpate Anus and Rectum
Instruct person that palpation is not painful but may feel like needing to move bowels
Drop lubricating jelly onto gloved index finger; place pad of index finger gently against anal verge
You will feel sphincter tighten, then relax; as it relaxes, flex ti
Palpate Anus and Rectum II
Rotate examination finger to palpate entire muscular ring
Canal should feel smooth and even; note intersphincteric groove circling canal wall
To assess tone, ask person to tighten muscle; sphincter should tighten evenly around with no pain to person
Use a
Palpate Anus and Rectum III
Above anal canal, rectum turns posteriorly, following curve of coccyx and sacrum
Insert examination finger farther and explore all around rectal wall; normally feels smooth with no nodularity
Promptly report any mass you discover for further examination
Prostate Gland II
On anterior wall in male, note elastic, bulging prostate gland
Palpate entire prostate in a systematic manner; note that only superior and part of lateral surfaces is accessible to examination
Press into gland at each location; when nodule occurs, it will
Prostate Gland Characteristics
-Size: 2.5 cm long by 4 cm
wide; should not protrude
more than 1 cm into rectum
-Shape: heart shape, with
palpable central groove
-Surface: smooth
-Consistency: elastic, rubbery
-Mobility: slightly movable
-Sensitivity: nontender to
palpation
Cervical Examination
Palpate cervix in female through anterior rectal wall
Normally feels like small round mass
May palpate retroverted uterus or tampon in vagina
Withdraw examination finger; normally no bright red blood or mucus is on glove
To complete examination, offer per
Examination of Stool
Inspect any feces remaining on glove
-Normally color is brown and
consistency is soft
-Test any stool on glove for
occult blood using specimen
container that your agency
directs
-Negative response is normal
-If stool Hematest is positive,
it indicates occ
Aging Adult
As an aging person performs Valsalva maneuver, you may note relaxation of perianal musculature and decreased sphincter control
Otherwise, full examination proceeds as that described for younger adult
Colorectal Cancer (CRC) Screening
Currently second leading cancer killer in the U.S.
However, it should not be; if everyone age 50 or older had regular screening tests, 60% deaths from this cancer could be avoided
Screening identifies precancerous polyps so they can be removed before they
CRC Screening Tests
Fecal occult blood test (FOBT)
Flexible sigmoidoscopy
Combination of FOBT and flexible sigmoidoscopy
Colonoscopy
Double-contrast barium enema
Pilonidal cyst or sinus
It occurs in the cleft at the top of the buttocks. A pilonidal cyst usually contains hair, dirt, and debris. It can cause severe pain and can often become infected. If it becomes infected, it may ooze pus and blood and have a foul odor
Anorectal fistula
An infected tunnel between the skin and the anus.
Fissure
very painful condition caused by trauma to the anus and anal canal, which then cuts or tears the anus and anal canal tissue.
Hemorrhoids
Swollen and inflamed veins in the rectum and anus that cause discomfort and bleeding.
Rectal prolapse
A condition that occurs when part of the large intestine slips outside the anus.
Pruritus ani
is a bothersome and sometimes intense itching or burning sensation of the skin around the anus (rectal opening). It is most noticeable at night or after a bowel movement. The most common complaint is an irresistible urge to scratch.
Abscess
A confined pocket of pus
rectal polyp
Polyps are abnormal growths that start in the inner lining of the colon or rectum
Fecal impaction
Hardened stool that's stuck in the rectum or lower colon due to chronic constipation.
Carcinoma
a cancer arising in the epithelial tissue of the skin or of the lining of the internal organs.
Benign prostatic hypertrophy (BPH)
Age-associated prostate gland enlargement that can cause urination difficulty.
Prostatitis
Swelling of the small walnut-sized gland (prostate) that produces seminal fluid.