Small bowel obstruction Flashcards
Mechanical obstruction to the passage of intraluminal contents
SBO
What are the signs and symptoms of SBO
Abdominal discofort Cramping nausea Abd distention Emesis HIGH-PITCHED bowel sounds
What are classic electrolyte/acid base findings with proximal obstruction
HYPO:volemic, chloremic, kalemic
ALKALOSIS
What must be ruled out on PE in patients with SBO
Incarcerated hernia (look for surgical scars)
What major Abdominal Xray
AIR-Fluid levels
Define complete SBO
Complete obstruction of the lumen
PAUCITY or NO colon gas
Danger of Complete SBO
Closed loop STRANGULATION of the bowel leading to bowel NECROSIS
Define partial SBO
some colon gas
What is the initial management of all patients with SBO?
NPO, NGT, IVF, FC
What TESTS can differentiate PARTIAL form COMPLETE SBO?
CT with oral contrast, small bowel follow-through
Causes of SBO? (ABCs)
- Adhesions
- Bulge (hernias)
- Cancer and tumors
What are other causes of SBO?
GIVES BAD CRAMPS! G allstone ileus I intussusception V olvulus E xternal compression S MA syndome
Bezoars, Bowel wall hematoma
A bscesses
D iverticulitis
C rohn's disease Radiation enteritis A Annular pancreas M eckel's P ertioneal adhesions S tricture
What is superior mesenteric artery (SMA) syndrome?
Seen with weight loss - SMA compresses duodenum, causing obstruction
What is the treatment of complete SBO?
Laparotomy and lysis of adhestions (LOA)
Treatment of incomplete SBO?
Initially, conservative treatment with close observation plus NGT decompression
Intraoperatively, how can the level of obstruction be determined in patients with SBO?
DILATED proximal to DECOMPRESSED bowel distal to the obstruction
What is the most common indication for abdominal surgery in patient’s with Crohn’ss disease?
SBO due to STRICTURES!
Can a patient have complete SBO and bowel movements and flatus?
Yes, the bowel distal to the obstruction can clear out gas and stool
After small bowel resection, why should the mesenteric defect always be closed?
To prevent internal hernia
What may cause SBO if patient is on COUMADIN?
Bowel wall ischemia
What is the #1 cause of SBO around the world?
Hernias
What is the #1 cause of SBO in children?
Hernias
What are the signs of strangulated bowel with SBO?
FEVER PAIN -severe/continuous SHOCK hematemesis gas in bowel wall or portal vain abdominal free air PERITONEAL SINGS ACIDOSIS(inceased lactic acid)
What are the clinical parameters that will lower the the threshold to operate on a partial SBO?
Increasing WBC
Fever
Tachycardia
Abdominal pain
What is the absolute indication for operation with PARTIAL SBO
Peritoneal signs, free air on AXR
What classic saying is associated with complete SBO?
“Never let the sun set or rise on complete SBO”
What condition commonly MIMICS SBO?
Paralytic ileus (AXR reveals gas distention THROUGHOUT, including the colon)
What is the differential diagnosis of paralytic (non obstructive) ileus?
Post operative ileus after abdominal surgery (usually resolves 3-5 days)
Electrolyte abnormalities (hypokalemia MC)
Medications (anticholinergics, narcotics)
Inflammatory intra-abdominal process
Sepis/shock
Spine injury
What tumor classically causes SBO due to “mesenteric fibrosis”?
Carcinoid tumor
