GI 1 Flashcards
(54 cards)
Clinical features of SBO?
VITAL SIGNS - tachycardia - hypotension - pyrexia TENDERNESS --> If localised = impending perforation --> If diffuse = perforation SWELLING - discrete lump/diffuse (=more common) RESONANCE --> tympanic if gas filled, dull if fluid filled. BOWEL SOUNDS --> Increased in early stage and absent at late stage.
What does ‘thumb-printing’ of bowel indicate? (seen on XR)
Ischaemia
Why would you not do CT in pt with peritonitis and SBO?
Pt will be v unwell and will hurt to move and regardless of CT result will require surgery, therefore CT unnecessary.
In what pt group is intussusception most common and why?
Infants/toddlers - mesentery less formed and more easily inverted. (more supple)
When would you operate IMMEDIATELY in a pt with SBO?
- signs of strangulation (radiologically/clinically)
- perforation (clinical peritonitis &/or free air on radiological imaging)
Why would you find low Hb levels in LBO?
Anaemia due to chronic occult blood loss.
What is the most commonly used investigation to diagnose LBO and what would it show?
CT - shows underlying cause, dilation of colon and risk of perforation –> allows staging of disease
Mx of non-perforated sigmoid volvulus?
Flexible/rigid sigmoidoscopy
Mx of perforated sigmoid volvulus?
Surgical resection and wash out
Pathophysiology of familial adenomatous polyposis?
BETA CATENIN not broken down ∴ levels increase –> Beta-catenin entering nucleus & binding to DNA which triggers epi. proliferation –> polyps formation –> adenoma formation.
Pathophysiology of hereditary nonpolyposis colorectal cancer (HNPCC)?
Loss of DNA repair proteins ∴ no DNA repair occurs. This –> to cancer as damaged DNA not recognised, apoptosis not triggered and ∴ cancer cells persist.
Define adenoma
A benign epithelial tumour in which the cells are derived from glandular epi.
What investigation is most commonly used to detect volvulus and what would it show?
Abdominal XR - shows characteristic INVERTED “U-LOOP” (looks like a coffee bean)
Who is most likely to develop sigmoid volvulus?
Elderly
Constipated
Comorbid pts
Complications of volvulus
Perforation and FATAL peritonitis
Presentation of gastro-oesophageal obstruction?
Classic triad of: - vomiting (then retching) - pain - failed attempts to pass a NG tube (Also see regurgitation of saliva)
3 possible (broad) locations/mechanisms of intestinal obstruction
- Intraluminal obstruction
- -> tumour/diaphragm disease/ meconium ileus/ gallstone ileus
- Intramural obstruction
- -> inflam. (eg. Crohn’s)/tumours/neural (eg. Hirschsprung’s disease)
- Extraluminal obstruction
- -> adhesions/volvulus/tumour
What must be present in order for volvulus to occur?
Mesentery
How do you eradicate H. pylori
Triple therapy
- amoxicillin
- clarithromycin
- PPI eg. omeprazole
define atresia
= Absence of opening/failure of development of hollow structure.
What is a feature of LBO not seen in SBO?
Weight loss
What is paralytic ileus
Abnormal peristalsis causing an a-dynamic bowel –> function bowel obstruction
- -> decrease bowel sounds
- -> absence of pain
where do you find Pseudo-obstruction of bowel
Only in large bowel causing pain and obstruction
What is the clinical presentation of acute mesenteric ischaemia?
triad:
abdo pain
no abdo signs
hypovolaemia –> shock
