CERTIFIED OSTOMY CARE NURSE (COCN) — 100 Practice
Questions with Rationales
This comprehensive resource contains 100 practice questions for the COCN® certification
exam through WOCNCB. Questions focus specifically on ostomy care (fecal and urinary diversions,
stoma types, complications, pouching, and patient education). Each question includes four answer
options, the correct answer, and a detailed rationale.
PART 1: OSTOMY TYPES AND SURGICAL CONSTRUCTION (1-20)
Question 1
An end colostomy is created by:
A) Bringing a loop of bowel to the skin surface with a supporting rod
B) Transecting the bowel and bringing the proximal end to the skin as a single stoma
C) Bringing both ends of transected bowel to the skin (functional end and mucous fistula)
D) Creating an internal reservoir without an external stoma
Correct Answer: B
Rationale: An end colostomy is created by transecting the bowel and bringing the proximal
(functional) end to the skin surface as a single stoma. The distal segment may be removed, oversewn
(Hartmann's pouch), or brought to skin as a mucous fistula (then called a double-barrel colostomy -
option C). Loop colostomy (A) involves a loop of bowel with a supporting rod. Continent diversion (D)
has no external stoma.
Question 2
A patient with a descending colostomy will most likely have stool that is:
A) Liquid to semi-liquid
B) Pasty to semi-formed
C) Formed solid stool (similar to pre-surgery)
D) Watery with high enzyme content
Correct Answer: C
Rationale: Descending and sigmoid colostomies are located in the left colon, where most water
absorption has already occurred. Output is typically formed solid stool (similar to normal bowel
movements). Ascending colostomy (A) produces liquid to semi-liquid. Transverse colostomy (B)
produces pasty to semi-formed. Ileostomy (D) produces watery, enzyme-rich output.
,Question 3
A Kock pouch (continent ileostomy) differs from a conventional ileostomy because:
A) It has an external stoma with continuous drainage
B) It has an internal reservoir and a nipple valve that allows intermittent catheterization (no external
pouch needed)
C) It is not connected to the bowel
D) It is temporary only
Correct Answer: B
Rationale: A Kock pouch (continent ileostomy) uses an ileal reservoir with a nipple valve
(intussuscepted segment) that prevents leakage. Patients catheterize the stoma 3-6 times daily to drain
the reservoir; no external pouch is needed. This is different from conventional ileostomy, which
continuously drains into an external pouch.
Question 4
An ileal conduit (urostomy) is constructed using:
A) Sigmoid colon
B) Terminal ileum (ileal segment)
C) Jejunum
D) Stomach
Correct Answer: B
Rationale: An ileal conduit uses a segment of terminal ileum (10-15 cm) that is isolated (bowel
continuity re-established). The ureters are implanted into the isolated ileal segment (ureteroileal
anastomosis), and one end is brought to the skin as a stoma. Urine drains continuously into an
external pouch. Sigmoid colon (A) can be used for a colon conduit but is less common.
Question 5
The optimal stoma site is located:
A) Within 2 cm of the umbilicus
B) Through the rectus abdominis muscle, away from bony prominences, skin folds, and belt line, visible
to the patient
C) Over the iliac crest for stability
D) In the midline directly over the previous surgical incision
Correct Answer: B
,Rationale: Optimal stoma site: through the rectus abdominis muscle (reduces hernia risk), away from
bony prominences (costal margin, iliac crest), away from skin folds/creases (for better pouching seal),
below the belt line (so clothing/belt doesn't compress stoma), and visible to the patient (for self-care).
Marked preoperatively with patient in sitting, standing, lying positions.
Question 6
Why should the stoma be sited away from the umbilicus?
A) Umbilicus is too high
B) Umbilicus is a common site for hernias, scars, and skin folds, making pouching difficult
C) Blood supply is poor
D) Stoma would be invisible to the patient
Correct Answer: B
Rationale: The umbilicus is a scarred, often concave area with potential for skin folds and hernias
(incisional or umbilical). Pouching over the umbilicus leads to poor seal, leakage, and skin breakdown.
Stoma should be placed at least 3-5 cm away from the umbilicus.
Question 7
A patient with an ileostomy is at risk for which type of obstruction?
A) Fecal impaction
B) High fiber food obstruction (e.g., corn, nuts, mushrooms, seeds)
C) Hard stool obstruction
D) Urinary stones
Correct Answer: B
Rationale: Ileostomy patients have a narrow lumen and must avoid high-fiber foods (raw vegetables,
corn, nuts, seeds, popcorn, mushrooms, dried fruit, celery) that can cause food bolus obstruction
(mechanical blockage). Obstruction presents with cramping, nausea, vomiting, and no output. Hard
stool obstruction (C) is more common in colostomies.
Question 8
The normal color of a healthy stoma is:
A) Pale pink
B) Bright red to dark pink (like oral mucosa)
C) Dusky purple
D) Black
, Correct Answer: B
Rationale: A healthy stoma is bright red to dark pink (similar to the color of the inside of the
mouth/oral mucosa), moist, and slightly raised. Pale (A) suggests anemia or ischemia. Dusky purple (C)
suggests venous congestion or early ischemia. Black (D) indicates necrosis requiring surgical revision.
Question 9
Stomal edema is expected in the immediate postoperative period and typically resolves within:
A) 2-4 hours
B) 1-2 days
C) 6-8 weeks
D) 1 year
Correct Answer: C
Rationale: Stomal edema is normal postoperatively, peaking in the first 48-72 hours. Edema gradually
subsides over 6-8 weeks. The stoma will shrink in size (often from 35-40mm to 25-30mm), requiring
re-measurement and recutting of the wafer opening during this period.
Question 10
A patient with a colostomy reports the stoma is 45 mm on postoperative day 2. For a well-fitting wafer,
the nurse should cut the opening:
A) To 45 mm (exact size of stoma)
B) To 46-47 mm (1-2 mm larger than stoma)
C) To 50 mm (much larger than stoma)
D) To 40 mm (smaller than stoma)
Correct Answer: B
Rationale: The wafer opening should be cut 1-2 mm larger than the stoma measurement to prevent
friction/abrasion (which causes bleeding, trauma, and stenosis) while avoiding skin exposure to
effluent. Exact size (A) risks trauma. Too large (C) exposes skin to effluent. Too small (D) cuts into
stoma.
Question 11
The optimal stoma height for an ileostomy is:
A) Flush to skin (0 cm)
B) 0.5-1.5 cm
Questions with Rationales
This comprehensive resource contains 100 practice questions for the COCN® certification
exam through WOCNCB. Questions focus specifically on ostomy care (fecal and urinary diversions,
stoma types, complications, pouching, and patient education). Each question includes four answer
options, the correct answer, and a detailed rationale.
PART 1: OSTOMY TYPES AND SURGICAL CONSTRUCTION (1-20)
Question 1
An end colostomy is created by:
A) Bringing a loop of bowel to the skin surface with a supporting rod
B) Transecting the bowel and bringing the proximal end to the skin as a single stoma
C) Bringing both ends of transected bowel to the skin (functional end and mucous fistula)
D) Creating an internal reservoir without an external stoma
Correct Answer: B
Rationale: An end colostomy is created by transecting the bowel and bringing the proximal
(functional) end to the skin surface as a single stoma. The distal segment may be removed, oversewn
(Hartmann's pouch), or brought to skin as a mucous fistula (then called a double-barrel colostomy -
option C). Loop colostomy (A) involves a loop of bowel with a supporting rod. Continent diversion (D)
has no external stoma.
Question 2
A patient with a descending colostomy will most likely have stool that is:
A) Liquid to semi-liquid
B) Pasty to semi-formed
C) Formed solid stool (similar to pre-surgery)
D) Watery with high enzyme content
Correct Answer: C
Rationale: Descending and sigmoid colostomies are located in the left colon, where most water
absorption has already occurred. Output is typically formed solid stool (similar to normal bowel
movements). Ascending colostomy (A) produces liquid to semi-liquid. Transverse colostomy (B)
produces pasty to semi-formed. Ileostomy (D) produces watery, enzyme-rich output.
,Question 3
A Kock pouch (continent ileostomy) differs from a conventional ileostomy because:
A) It has an external stoma with continuous drainage
B) It has an internal reservoir and a nipple valve that allows intermittent catheterization (no external
pouch needed)
C) It is not connected to the bowel
D) It is temporary only
Correct Answer: B
Rationale: A Kock pouch (continent ileostomy) uses an ileal reservoir with a nipple valve
(intussuscepted segment) that prevents leakage. Patients catheterize the stoma 3-6 times daily to drain
the reservoir; no external pouch is needed. This is different from conventional ileostomy, which
continuously drains into an external pouch.
Question 4
An ileal conduit (urostomy) is constructed using:
A) Sigmoid colon
B) Terminal ileum (ileal segment)
C) Jejunum
D) Stomach
Correct Answer: B
Rationale: An ileal conduit uses a segment of terminal ileum (10-15 cm) that is isolated (bowel
continuity re-established). The ureters are implanted into the isolated ileal segment (ureteroileal
anastomosis), and one end is brought to the skin as a stoma. Urine drains continuously into an
external pouch. Sigmoid colon (A) can be used for a colon conduit but is less common.
Question 5
The optimal stoma site is located:
A) Within 2 cm of the umbilicus
B) Through the rectus abdominis muscle, away from bony prominences, skin folds, and belt line, visible
to the patient
C) Over the iliac crest for stability
D) In the midline directly over the previous surgical incision
Correct Answer: B
,Rationale: Optimal stoma site: through the rectus abdominis muscle (reduces hernia risk), away from
bony prominences (costal margin, iliac crest), away from skin folds/creases (for better pouching seal),
below the belt line (so clothing/belt doesn't compress stoma), and visible to the patient (for self-care).
Marked preoperatively with patient in sitting, standing, lying positions.
Question 6
Why should the stoma be sited away from the umbilicus?
A) Umbilicus is too high
B) Umbilicus is a common site for hernias, scars, and skin folds, making pouching difficult
C) Blood supply is poor
D) Stoma would be invisible to the patient
Correct Answer: B
Rationale: The umbilicus is a scarred, often concave area with potential for skin folds and hernias
(incisional or umbilical). Pouching over the umbilicus leads to poor seal, leakage, and skin breakdown.
Stoma should be placed at least 3-5 cm away from the umbilicus.
Question 7
A patient with an ileostomy is at risk for which type of obstruction?
A) Fecal impaction
B) High fiber food obstruction (e.g., corn, nuts, mushrooms, seeds)
C) Hard stool obstruction
D) Urinary stones
Correct Answer: B
Rationale: Ileostomy patients have a narrow lumen and must avoid high-fiber foods (raw vegetables,
corn, nuts, seeds, popcorn, mushrooms, dried fruit, celery) that can cause food bolus obstruction
(mechanical blockage). Obstruction presents with cramping, nausea, vomiting, and no output. Hard
stool obstruction (C) is more common in colostomies.
Question 8
The normal color of a healthy stoma is:
A) Pale pink
B) Bright red to dark pink (like oral mucosa)
C) Dusky purple
D) Black
, Correct Answer: B
Rationale: A healthy stoma is bright red to dark pink (similar to the color of the inside of the
mouth/oral mucosa), moist, and slightly raised. Pale (A) suggests anemia or ischemia. Dusky purple (C)
suggests venous congestion or early ischemia. Black (D) indicates necrosis requiring surgical revision.
Question 9
Stomal edema is expected in the immediate postoperative period and typically resolves within:
A) 2-4 hours
B) 1-2 days
C) 6-8 weeks
D) 1 year
Correct Answer: C
Rationale: Stomal edema is normal postoperatively, peaking in the first 48-72 hours. Edema gradually
subsides over 6-8 weeks. The stoma will shrink in size (often from 35-40mm to 25-30mm), requiring
re-measurement and recutting of the wafer opening during this period.
Question 10
A patient with a colostomy reports the stoma is 45 mm on postoperative day 2. For a well-fitting wafer,
the nurse should cut the opening:
A) To 45 mm (exact size of stoma)
B) To 46-47 mm (1-2 mm larger than stoma)
C) To 50 mm (much larger than stoma)
D) To 40 mm (smaller than stoma)
Correct Answer: B
Rationale: The wafer opening should be cut 1-2 mm larger than the stoma measurement to prevent
friction/abrasion (which causes bleeding, trauma, and stenosis) while avoiding skin exposure to
effluent. Exact size (A) risks trauma. Too large (C) exposes skin to effluent. Too small (D) cuts into
stoma.
Question 11
The optimal stoma height for an ileostomy is:
A) Flush to skin (0 cm)
B) 0.5-1.5 cm
