Small Bowel Obstruction

Question 1

What percentage of all small bowel obstruction (SBO) cases are due to postoperative adhesions?

Answer 1

75% to 80%

Question 2

Name some congenital anatomic abnormalities that can cause SBO.

Answer 2

Midgut volvulus
Ileal atresia
De novo adhesions

Question 3

What are some disorders of the bowel wall that can lead to SBO?

Answer 3

Intussusception
Stricture
Tumor

Question 4

List examples of extrinsic compression causes of SBO.

Answer 4

Compression from a mass

Question 5

What are some intraluminal disorders that can cause SBO?

Answer 5

Meconium ileus
Gallstones
Foreign body
Bezoar

Question 6

What is the most common cause of SBO in undeveloped countries?

Answer 6

Strangulated hernias

Question 7

Give examples of foreign bodies that can cause SBO.

Answer 7

Bezoars
Swallowed objects
Gallstones

Question 8

Name additional causes of SBO not related to adhesions or hernias.

Answer 8

Radiation
Endometriosis
Infection (e.g., tuberculosis)

Question 9

In the absence of prior intraabdominal surgery, what is the most common cause of SBO?

Answer 9

Abdominal wall hernia with small bowel incarceration

Question 10

What should be considered in older patients with suspected SBO, no prior abdominal surgery, and no hernia on examination?

Answer 10

Evaluation for malignancy

Question 11

Leukocytosis with a left shift in SBO

Answer 11

nonspecific indicator of inflammation and/ or infection

does not correlate with disease severity.

Question 12

The typical gas pattern for SBO on plain film demonstrates

Answer 12

dilated gas- or fluid-filled loops of small bowel in the setting of a gasless or nondistended colon

Question 13

what may be given in partial adhesive SBO at a later point to expedite resolution of the obstruction

Answer 13

Gastrografin

Question 14

Ct Findings concerning for bowel wall compromise include

Answer 14

bowel wall edema or hemorrhage
altered bowel wall enhancement (Decreased,Absent or Delayed hyperenhancement)
interloop ascites
mesenteric edema/ fat stranding
vascular engorgement
vessel occlusion

Question 15

late signs of bowel wall compromise and indicate bowel wall necrosis in the setting of SBO.

Answer 15

pneumatosis of the bowel wall
mesenteric and/ or portal venous gas,
extraluminal free air

Question 16

When to use MRI ?

Answer 16

Pregnant
Children

Question 17

the three CT patterns of closed-loop small bowel obstruction

Answer 17

1- typical closed-loop obstruction, the afferent loop and closed loop are dilated and the efferent loop is collapsed.

2- collapsed closed-loop obstruction, the closed loop is collapsed, the afferent loop is dilated, and the efferent loop is collapsed

3- flat-belly closed-loop obstruction, the closed loop is dilated and the afferent and efferent loops are collapsed.

Question 18

partial small bowel obstruction (pSBO)

Answer 18

contents continue to pass through the intestine.

Patient exhibit a benign abdominal examination and continue to pass bowel movements and flatus.

Question 19

Concerning Radiographic Signs other than Previous mentioned

Answer 19

-Multiple transition zones: Closed-loop obstruction demonstrates radial small bowel arrangement with a U- or C-shaped configuration, converging at the site of obstruction.

-Swirling of mesenteric vessels (also known as the swirl sign or whirl sign) may indicate volvulus and/ or closed-loop obstruction.

Question 20

When to do Expectant therapy for SBO

Answer 20

recommended for patients without peritonitis or hemodynamic instability

Question 21

Patients with partial adhesive SBO without strangulation are good candidates for

Answer 21

-Gastrografin (diagnostic and therapeutic)

-Doses of 100 mL in 50 mL of water

-Either immediately at admission, or if conservative therapy with decompression fails, after 48 hours.

-Gastrografin appearing in the colon within 24 hours on x-ray study predicts resolution without surgical intervention.

-The radiograph can be repeated every 8 to 12

Question 22

Nonoperative techniques can be utilized for how long ?

Answer 22

2 to 3 days

spontaneous resolution decreases after the third day

Question 23

Predictors for successful laparoscopic treatment

Answer 23

history of ≤ 2 laparotomies
appendectomy as the sole previous operation and cause of the obstruction
no previous median laparotomy incision
and a single adhesive band.

Question 24

Patient with irreducible hernia SBO

Answer 24

You can reduce the bowel and monitor post– hernia reduction (typically at least 24 hours) if there are no concerns for bowel compromise.

Question 25

One-half of reported SBO cases during pregnancy are

Answer 25

caused by adhesions.

Question 26

Fetal mortality averages 21% and is more likely with surgery in the (Which Trimester ?)

Answer 26

first trimester

Question 27

Obstruction Due to Inflammatory Bowel Disease

Answer 27

-Early CT enterography is essential

-The team should determine early surgery versus neoadjuvant antiinflammatory therapy and the need for antibiotics and/ or abscess drainage.

Question 28

Malignancy Causing SBO like ?

Answer 28

neuroendocrine tumors
adenocarcinomas
lymphomas
gastrointestinal stromal tumors.

Question 29

How would you Treat the Previous ?

Answer 29

oncologic principles > resection of the involved segment of bowel along with a 5- to 10-cm margin proximally and distally as well as removal of all associated mesentery.

Question 30

When to Consider A small bowel bypass

Answer 30

If the tumor causing the obstruction cannot be completely resected and multiple sites of bowel obstruction exist

Question 31

SBO in virgin abdomen (VA) Benign or Malignant ?

Answer 31

-mostly benign cause; in contrast with older literature and surgical textbooks that suggest malignancy as the main cause of obstruction in VA patients.

Question 32

How would you Tx the Previous

Answer 32

can be treated by nonoperative trial initially.

Nevertheless, a laparotomy remains indicated in case of a nonresolving obstruction.

Question 33

Post Bariatric Surgery at risk of What ?

Answer 33

same causes as all other patients +
risk of internal hernia
intussusception
and closed-loop obstructions resulting from surgical creation of mesenteric defects.

Question 34

Findings for patient post Bariatric Sx

Answer 34

-significantly dilated small bowel with a transition point is often a late finding.

-Elevated amylase and/ or lipase may be a significant finding , especially with acute obstruction of the biliopancreatic limb.

lower threshold to proceed to the operating room for any suspicious findings is recommended.