Anus, Rectum and Prostate

Question 1

What is defacation controlled by?

Answer 1

Striated external sphincter, which is under voluntary control
Lower half of rectal canal is supplied with somatic senory nerves, making it sensitive to painful stimuli
Upper half is autonomic

Question 2

Columns of Morgagni

Answer 2

Anal canal lines by columns of mucosal tissue part of anorectal junction
Inflammation of crypts (lie between columns of mucosa) can cause fistula or fissure formation

Question 3

Zona Hemorrhoidalis

Answer 3

Anastomosing veins that cross the columns

Dilation of these veins cause internal hemorrhoids

Question 4

Lower segment contains plexus veins

Answer 4

Drains into inferior rectal veins

Dilation of these veins can result in external hemorrhoids

Question 5

Rectal Ampulla

Answer 5

Stores flatus and feces

Question 6

Houston Valves

Answer 6

Three semilunar transverse folds that line the rectal walls

Question 7

A&P of Infants

Answer 7

Anal opening developed by 8 weeks of gestation
Meconium stool first passed within first 24 to 48 hours
Gastrocolic reflex - passing of stool after each breastfeeding
Internal and external sphincters are involuntary d/t myelination of spinal cord is not complete
1-2 BMs daily after first year
Toileting begins at age 2-4 years old
Girls develop bladder control before boys
Bowel control is achieved first
Prostate develops at puberty

Question 8

A&P of pregnant

Answer 8

Pressure increases in veins below uterus
Constipation d/t dietary habity and hormonal changes decrease GI tone and motility
Predispose pregnant women to developing hemorrhoids
Labor may cause protriusion and inflammation of hemorrhoids

Question 9

A&P of Older Adults

Answer 9

Degeneration of afferent neurons interferes with relaxation of internal anal sphincter in response to distention of rectum
Causes retention of stool
External sphincter cannot control bowels by itself and causes fecal incontinence
Atrophy of aging obscured by benign hyperplasia
Prostate replaced by collagen

Question 10

Positioning of the patient

Answer 10

Knee-chest, lithotomy, left lateral with hips and knees flexed or standing with hips flexed and the upper body supported on the table
Latter two positions are satisfactory in adult males

Visualize perianal and sacrococcygeal areas

Question 11

Sacrococcygeal and Perianal Areas

Answer 11

Skin should be smooth and uninterrupted
Inspect for lumps, rashes, inflammation, excoriation, scars and pilonidal dimpling and tufts of hair
Fungal infection and pinworm can cause irritation
Fungal infection more common in those with DM, and pinworms more common in children
Palpate the area for tenderness inflammation, abscess, fistula or fissurem pilonidal cyst or pruritus ani

Question 12

Anus

Answer 12

Darker pigmented
Lesions, tags and warts, external hemorrhoids, fissures and fistulae
Bearing down will reveal fistulae, fissures, rectal prolapse, polyps and internal hemorrhoids

Question 13

Sphincter

Answer 13

Should tighten evenly with no discomfort
Lax sphincter may be neurologic defecit or SA
Extremely tight sphincter can result from scarring, spasticity caused by a fissure or other lesion, inflammation or anxiety
Anal fistula or fissure can produce extreme tenderness
Rectal pain usually means local infection
Look for inflammation, rock-hard constipation, rectal fissures, fluctulance from perirectal abscess or thrombosed hemorroids

Question 14

Anal Ring

Answer 14

Smooth and exert pressure on finger

Note nodules or irregularities

Question 15

Lateral and Posterior Walls

Answer 15

Nodules, masses, irregularities, polyps, tenderness
Smooth, even, uninterrupted
Finger can palpate a distance of 6-10cm
Internal hemorrhoids usually not felt unless thromboses

Question 16

Bidigital Palpation

Answer 16

Useful for detecting perianal abscesses

Question 17

Anterior Rectal Wall

Answer 17

Shelf lesiosn are palpable above prostate and in the cul-de-sac of females

Question 18

Prostate

Answer 18

Size, contour, consistency and mobility
Should feel firm, smooth, and slightly movable and nontender
Healthy prostate has diameter of 4cm with less than 1cm protrusion into rectum
Greater protrusion could be enlargement

Question 19

Abnormalities of Prostate

Answer 19

Rubbery or boggy consistency is usually benign hypertrophy
Stony hard nodularity indicates carcinoma, prostatic calculi or chronic fibrosis
A tender softness indicates prostatic abscess
Prostatic lobes should be symmetric
Seminal vesicles not palpable unless inflammed
Palpation can force secretions through the urethral orifice which should be collected

Question 20

Stool

Answer 20

Should be soft and brown
Note any blood or pus
Very light tan or gray stool can indicate obstructive jaundice
Tarry black stool is usually intestinal tract bleeding
Use chemical guaiac procedure to test for blood

Question 21

Inspection of infants

Answer 21

Examination usually only required when there are symptoms present
Mass, tenderness, bladder distention, bleeding, or rectal or bowel abnormalities
Inspect tender perirectal protrusion, abscesses, and possibly rectal fistulae
Shrunken buttocks indicates chronic disease
Asymmetric creases indicates congenital dislocation of the hips
Pinworms or candida = redness and irritation

Question 22

Palpation of Infants

Answer 22

Rectal prolapse results from constipation, diarrhea or sometimes severe cough
Hemorrhoids are rare and indicate serious problem like portal HTN
Small flat flaps of skin around rectum indicate HPV
Sinuses, or tufts of hair and dimping of pilonidal area indicate lower occult spinal deformity

Question 23

More palpation of infants

Answer 23

Lightly touch anal opening to produce “anal wink”. Lack of contractions may indicate lower spinal cord lesion or chronic abuse
Test patency by confirming passage of meconium or initial rectal temperature
Perianal fistula may be confused with anal orifice
Suspect rectal atresia, Hirschsprung disease, or CF if not passage of stool in first 24 hours.

Question 24

Rectal Exam in infants

Answer 24

Tight spincters can lead to stool retention or pain on BM
Lax spincter is associated c llesions of peripheral spinal nerves or spinal cord, Shigella infection and previous fecal impactions
Bruises, anal scars and dilation = SA
Cognitive deficiency or emotional problems lead to constipation
Hirschsprung = empty rectum in presence of constipation
Fecal mass acoompanying diarrhea suggests overflow diarrhea
Stool recovered should be tested for occult stool

Question 25

Palpation of prostate in infants

Answer 25

Usually not felt, but if felt before puberty indicates precocious puberty or virilizing disease process
Rectum can be examined with proctoscope or otoscope

Question 26

Pregnant Women

Answer 26

Assess for internal and external hemorrhoids
More common late pregnancy
Size, extent, location, discomfort, signs of infection or bleeding

Question 27

Older Adults

Answer 27

Sphincter tone decreased
More likely to have enlarged prostate, smooth, rubbery and symmetric
Median sulcus may be obliterated
More likely to have polyps and carcinoma