Intestinal Obstruction Flashcards
What are the sx of bowel obstruction?
Vomiting
-undigested food in gastric outlet obstruction
-bilious vomiting in upper SBO
-faeculent vomiting in distal SBO
Pain
-colicky abdo pain in early obstruction
-pain absent in long-standing obstruction
Constipation (not absolute in proximal obstruction)
What are the signs of bowel obstruction?
Distention
Tinkling bowel sounds
Dehydration
Central resonance to percussion w/ dull flanks
Scars (prev surgery causing adhesions)
Palpable mass (causing obstruction)
NO ABDO TENDERNESS (unless strangulation)
What are the common causes of small bowel obstruction?
Adhesions (80%)
Herniae
Chron’s disease
Intussusception
What are the common causes of large bowel obstruction?
Carcinoma of the colon
Diverticular disease
Sigmoid volvulus
Constipation
What are the complications of bowel obstruction?
Strangulation (ischaemia & necrosis)
Bacterial proliferation
Bowel perforation
What are the appropriate investigations in suspected bowel obstruction?
Bloods - FBC, U&Es, amylase, LFTs, ABG
Urinalysis
Supine AXR (distended proximal bowel, absent gas distally)
Erect CXR (fluid levels in SBO, air under diaphragm)
Contrast enema (obstruction vs pseudo-obstruction)
CT
What is a paralytic ileus?
Temporary disruption of normal peristaltic activity w/o mechanical blockage
What are the causes of a paralytic ileus?
Post-surgery (normal <4/7)
Due to anastamotic leak/intra-abdominal sepsis
Electrolyte disturbances
Critically unwell pts on ITU w/ multiple injuries
What is the management of a paralytic ileus?
NBM w/ NG feeding
What is the main potential complication of a post-op paralytic ileus?
May develop into mechanical ileus caused by adhesions
How can a paralytic and mechanical ileus be distinguished?
Bowel sounds -absent in paralytic -present in SBO AXR -one air-fluid level in paralytic -variable air-fluid levels in SBO
What is pseudo-obstruction?
Large bowel obstruction when no identifiable cause can be found
What are the clinical features of strangulation?
Increasing pain/tenderness Peritonism Absent bowel sounds Leukocytosis Systemic upset
What is a volvulus?
Twisting loop of bowel around mesenteric axis, resulting in obstruction and venous occlusion at base of mesentery
What are the two common types of volvulus?
Sigmoid
Caecal
What are the features of a sigmoid volvulus?
Most common in elderly, constipated pts
‘Coffee bean’ appearance on AXR
Treated by insertion of long flatus tube into sigmoid
-can require emergency laparotomy
What are the features of a caecal volvulus?
Due to congenital malrotation
‘embryo’ appearance of ectopically placed caecum on AXR
Treated by untwisting at laparotomy
How can small and large bowel obstruction be distinguished?
Vomiting -absent/faeculant in LBO -bilious in SBO Constipatin -absolute in LBO -may not be absolute in SBO Progression -more rapid in SBO
How should small bowel obstruction be managed?
A-E resus
NBM + NG decompression of stomach (Ryle’s tube)
Surgical management & a/b if signs of strangulation
How should large bowel obstruction be managed?
Operative management (Hartmann's procedure) If due to faecal impaction enemas/manual evacuation
What are the most common causes of intestinal obstruction in children?
Intussusception Incarcerated hernias Malrotation of bowel w/ midgut volvulus Hirschsprung's disease Meconium ileus (CF pts)
What are the features of intussusception in children?
3mo-6yrs Intermittent colic Redcurrent jelly PR bleeding (late sign) Sausage shaped mass in upper abdo TREAT W/ AIR INSUFFLATION
What are the features of malrotation in children?
Obstruction
PR blood/mucous
Abnormal bowel positioning on AXR w/ contrast
What are the features of Hirschsprung’s in children?
Failure to pass meconium
Bilious vomiting
