Gastro Flashcards
hepatic causes of jaundice (high indirect bilirubin)
Gilbert’s (decr UDPG activity)
Crigler Najjar (no UDPG)
Hepatitis
Newborn jaundice (not enough UDPG or lignin to deal with incr haem catabolism from conversion of HbF to HbA)
hepatic causes of jaundice (high direct bilirubin)
Hepatitis Drugs that impair excretion Rubin Johnson syndrome (no cMOAT for excretion) Tumours Cirrhosis
Post-Hepatic causes of jaundice
Due to high conjugated bilirubin:
Gallstones
Biliary strictures/obstruction
Cholangitis
Pancreatic or biliary tree cancer
All lead to cholestasis
What happens to bilirubin when it is unconjugated in the blood and liver?
Blood - bound to albumin
Liver - bound to ligandin
What sort of bilirubin is toxic and what does it cause in the brain?
Indirect is insoluble so cannot be excreted and builds up
Kernicterus due to brain toxicity
Which enzyme conjugates bilirubin and what happens if it is not present or has decr activity?
UDPG
Decr activity: Gilbert’s
Not present: Crippler Najjar
what happens to bilirubin in the gut?
Converted to urobilinogen via gut bacteria
then 90% is converted to stercobilin and excreted in faeces
10% absorbed into portal circulation and goes back to liver. 9% of this is recycled back to gut and 1% goes to kidneys and is excreted in urine
What colour is the pee and poo with:
obstructive jaundice?
pre-hepatic jaundice?
Obstructive: Dark wee, pale poo
Pre-hepatic: dark wee and poo (overwhelm liver conjugating enzymes)
What is a potential consequence of pre-hepatic jaundice?
Excess haem from haemolysis results in excess synthesis of bile salts which can result in precipitation of GALLSTONES
-> cholestasis -> obstructive jaundice
4 categories of mechanisms of diarrhoea
Osmotic
(excess unabsorbed substrates in gut lumen retain fluids)
Secretory
(stimulation of excretory mechanisms from enterocytes)
Inflammatory
(altered membrane permeability leads to exudation of protein, blood, mucus)
Altered intestinal motility
(slow or fast)
Common underlying cause of osmotic diarrhoea
FODMAPS (IBS)
Common underlying causes of secretory diarrhoea
Bacterial toxins
- ETEC
- Cholera
Laxative abuse
Hyperthyroidism
Common underlying causes of inflammatory diarrhoea
IBD
Invasive bacteria
- Shigella
- Salmonella
- Clostridium difficile
- Campylobacter
Entamoeba histolytica
CMV colitis
Common underlying causes of altered motility diarrhoea
SLOW: Anatomical defects causing intestinal stasis -strictures -blind loops (diverticulitis) -surgery
FAST:
- IBS
- Thyrotoxicosis
- Diabetic neuropathy
Appearance of poo with - inflammatory - secretory - osmotic Diarrhoea
Inflamm - blood and mucus, small volume
Secretory: watery, >1Lvol
Osmotic: fatty,
Acute abdomen - which causes need laparotomy and which don’t
Need laparotomy:
- Generalised peritonitis (perf ulcer, diverticulum, appendix, bowel, gallbladder)
- Ruptured organ (liver, spleen, AAA, ectopic pregnancy)
Doesn’t need:
- local peritonitis (cholecystitis, diverticulitis, salpingitis)
- suspected abscess
- localised ileus
- colicky pain (patient restless)
Maybe:
-SBO
Management of Acute abdomen
Treat shock w 2 large bore cannulas w crystalloid (Hartmann's) fluids ECG Vitals Group and hold Blood cultures Antibiotics (cef and met) Analgesia (IV morphine PRN) IV fluids Plain AXR and erect CXR Nil by mouth Antiemetics
Management of abdominal trauma (blunt)
§ ABCs, fluid resus and stabilisation
§ Surgery ?
□ Hollow organ injuries -> laparotomy
□ Solid organ injuries -> laparotomy if hemodynamically unstable or high transfusion requirements
Management of abdo trauma (penetrating)
§ ABCs § Fluid resuscitation and stabilization § Gunshot wounds require laparotomy § Laparotomy if penetrating trauma and □ Shock □ Peritonitis □ Evisceration □ Free air in abdomen □ Blood in NG tube, catheter or on DRE
§ Local wound exploration in some instances
Treatment for peritonitis
IV rehydration and electrolyte balance correction
IV antibiotics (cephalosporin, tazosin or carbepenem)
Laparotomy - exploratory peritoneal lavage and correction of anatomical defects
Treatment of ascites
1st line ○ Salt restriction (>2g daily) ○ Diuretics: spironolactone, frusemide ○ Weight loss If refractory (treatment with diuretics is inadequate) ○ Therapeutic/palliative ascitic taps ○ IV albumin ? Liver transplant
Complications of ascites and the treatment
Spontaneous bacteiral peritonitis if they develop fever, chills, abdo pain, hypotension, ARF etc
Treatment: IV antibiotics (cephalosporin) and IV albumin
Investigations for a suspected hernia
Ultrasound +/- CT
List different types of hernias
Inguinal hernias (direct vs indirect)
Femoral hernia
Umbilical
Paraumbilical (below or above umbilicus)
Epigastric (through lines alba above umbilicus)
Incisional hernia
Obturator hernia