INTESTINAL OBSTRUCTION Flashcards
what are abdominal quadrants important for?
- subdivide the anterolateral abdominal wall
- allows for more precise localization of clinical findings
- formed by the transumbilical line that crosses the umbilicus and the midline
what is the definition of an intestinal obstruction?
condition in which digested material is prevented from the passing normally though the bowel
what is intestinal obstruction classified by?
- mechanical obstruction
- functional obstruction
what is mechanical obstruction d/t?
physical blockage
what is functional obstruction d/t?
disruption of normal motility
where are the majority of intestinal obstructions?
small bowel (80%)
large is only 20%
what is a partial vs complete intestinal obstruction?
partial: some intestinal contents pass through
complete: no passage of luminal contents beyone obstruction point
what is the big 3 etiologies of mechanical obstruction?
- adhesions (post-surgical)
- tumors
- hernias
what are the other etiologies of mechanical SMALL BOWEL obstruction?
crohns
gallstones
volvulus
intussusception
foreign body ingestion
what are the big 2 etiologies of functional SMALL BOWEL obstruction?
- surgery
- medications: opiates, CCB, diuretics
what are the other etiologies of functional SMALL BOWEL obstruction?
peritonitis
trauma (pelvic, spinal fractures)
intestinal ischemia
electrolyte imbalance (hypokalemia)
what is the abc mnemonic for most common causes of SBO ?
A- adhesions
B- bulge (hernias)
C- cancer (tumor)
what are the big 2 etiologies of mechanical LBO?
- colorectal cancer: MOST COMMON CAUSE
- volvulus (sigmoid and cecal): MOST COMMON BENIGN CAUSE
what are the other etiologies of mechanical LBO?
- metastatic cancers (ovarian, pancreatic, lymphoma)
- strictures from: 1. prior colon resection, 2. inflammatory disease (diverticulitis, ischemic colitis, inflammatory bowel disease)
- post-surgical adhesions
- hernias
what are the 2 big etiologies of functional LBO?
- severe systemic illness
- surgery (most commonly from cesarean section or hip surgery)
what are the other etiologies of functional LBO?
- trauma
- spinal anesthesia
- medications (opiates, anticholinergics, CCB)
what is the pathogenesis of bowel obstruction?
- ingested fluids and food, digestive secretions, and gas accumulate above the obstruction causing the proximal bowel to distend
- bowel segment distal to obstruction collapses
- secretory and absorptive functions become depressed and bowel becomes edematous and congested
- distention is self- perpetuating and can lead to vascular compromise (venous then arterial)-> ischemia-> gangrene-> PERFORATION
when do sx of SBO occur?
they occur shortly after onset
what are the sx of SBO?
abdominal pain
- crampy or colicky in nature
- most often diffuse and intermittent
- severe and constant -> ischemia of perforation has developed
vomiting (bilious) - may report temporarily feels better because you relieve pressure
abd distention/bloating
obstipation
what are the sings of SBO?
bowel sounds are hyperactive, and high pitched EARLY ON
bowel sounds are decreased or absent LATER ON
percussion reveals tympany or hyper-resonance; dullness if fluid filled
what are the sx of LBO?
- mild and develop gradually
- abdominal pain usually below umbilicus that is crampy in nature
- abdominal distention/bloating
- vomiting (more common with right colon obstruction)
- obstipation
what are the signs of LBO?
- distended abdomen
- percussion: tympany
what are the 2 dx studies done for SBO?
- supine and upright abdominal x-rays with upright chest x-ray
- CT abdomen/pelvis
what dx study is usually adequate to dx obstruction?
supine and upright abdominal x-rays with upright chest x-ray
