Intestinal Problems 1, 2 and 3 - Intestinal failure, pathology of small bowel, malabsoprtion Flashcards
What is intestinal failure?
The inability to maintain adequate nutrition or fluid status via the intestines - can result from a number of things such as obstruction, dysmotiltiy, surgical resection, congenital defect, or disease associated with loss of absorption and is characterised by the inability to maintain protein-energy, fluid, electrolyte, or micronutrient balance
How can IF be classified in terms of time frame?
Acute short term = days/ weeks/ months e.g. mucositis post chemotherapyChronic long term e.g. short gut syndrome
How many different types of IF are there?
3
What types of IF are classified as acute short term?
Types 1 and 2
What types of IF are classified as chronic long term?
Type 3
What is type I intestinal failure?
Self-limiting short term postoperative or paralytic ileus (usually on wards, sometimes HDU/ ITU)
What is type 2 intestinal failure?
Prolonged, associated with sepsis and metabolic complications. Often related to abdominal surgery with complications (mainly HDU/ ITU or wards)
What is type 3 intestinal failure?
Long term but stable - home parenteral nutrition often indicated (usually seen in wards to home)
How malnourished will a patient with type I intestinal failure be?
Normal/ moderately malnourished
Treatment of a patient with type I intestinal failure? (7)
Replace fluids, correct electrolytesParenteral nutrition if unable to tolerate food/ fluids for greater than or equal to 7 days post opAcid suppression: PPIOctreotide (reduces GI secretions)Alpha hydroxycholecalciferol to preserve MgIntensive multi-disciplinary inputAllow some diet/ enteral feeding
What does parenteral nutrition rely on?
Venous access e.g. PICC line, tunnelled catheter (central line), vascuport (portacaf) - US guided placement
Parenteral nutrition complications?
Nutrient toxicityLiver diseaseMetabolic disturbancePhyscho-social effectsInappropriate usageSepsisSVC thrombosisLine fractureLine leakageLine migrationMetabolic bone disease
How long do patients with type 2 IF usually have it for?
Weeks/ months
What type of feeding should patients with type 2 IF usually receive?
Parenteral +/- some enteral feeding
What are some examples of causes of type 2 intestinal failure?
Usually a surgical complication but can be due to crohns, coeliac disease, malignancy, ischaemia, radiation, etc.
What is the treatment of choice for patients with chronic IF? (type III)
Home parenteral nutrition
What is another 3 treatment options for patients with type 3 intestinal failure, apart from parenteral nutrition?
Intestinal transplantation (specific indications, long term survival lower than HPN)Bowel lengthening (not validated yet in adults)GLP2 (teduglutide) treatment for SBS
What are examples of conditions that can cause type 3 intestinal failure?
Short gut syndromeCrohns diseaseNeoplasiaVascularMechanicalRadiation enteritisDysmotiity
What length must the bowel be to be classified as short bowel syndrome?
Less than 200cm - insufficient length of small bowel to meet nutritional needs without artificial nutritional support
What length of bowel is indicative that the patient requires HPN for their short bowel syndrome?
Less than 50cm of small bowelAlthough patients usually need it before due to a poor quality of life e.g. 100cm of small bowel
Do patients who go on HPN usually get weaned off it eventually/
Very rarely - there are usually dependent for life
What is the advantages of intestinal transplantion compared to HPN?
Transplantation = survival 5 years = 50-60% and the patient requires a stoma, risk of immunosuppression but eatingHPN = 5 year survival 80% but not eating
What are the main indications of small bowel transplant compared to HPN?
Loss of venous accessLiver disease (usually combined with a liver transplant)Last resort
Do palliative patients tend to get sent home with HPN?
Not usually - look at individual cases
What are the 2 causes of ischaemia of the small bowel?
Mesenteric arterial occlusionNon occlusive perfusion insufficiency
What are the 2 causes of mesenteric arterial occlusion?
Mesenteric artery atherosclerosisThromboembolism from the heart e.g. A fib
What are 4 causes of non occlusive perfusion insufficiency?
ShockStrangulation obstructing venous return e.g. hernia adhesionDrugs e.g. cocaineHyperviscosity
Is bowel ischaemia usually acute or chronic?
Usually acute but can be chronic
What part of the small bowel is most sensitive to the effects of hypoxia?
The mucosa - most metabolically active part
In non-occlusive ischaemia, when does most of the tissue damage occur?
After reperfusion
How is acute ischaemia classified?
By degree of infarction caused - mucosal infarct, mural infarct or transmural infarct (depending on the length of time of the ischaemia)
What are the 3 types of outcomes of acute ischaemia depending on the length of time the ischaemia has been present for?
RegenerationStrictureGangrene
What type of outcome does mucosal infarct usually have?
Regeneration - mucosal integrity restored
What type of outcome does mural infarct have?
Repair and regeneration = fibrous stricture
What type of outcome does transmural infarct have?
Gangrene - patient death if not resected
Complications of ischaemia of the small bowel? (10)
FibrosisStrictureChronic ischaemiaMesenteric anginaObstructionGangrenePerforationPeritonitisSepsisDeath
What is Meckel’s diverticulum?
A tubular structures, 2 inches long, 2 foot above the IC valve in 2% of people due to incomplete regression of vital-intestinal duct (may contain heterotopic gastric mucosa)
Symptoms of a meckels diverticulum?
May cause bleeding, perforation or diverticulitis which mimics appendicitis - commonly asymptomatic, incidental finding
Are primary or secondary tumours of the small bowel more common?
secondary (metastases) - ovary, colon, stomach
What type of primary tumours of the small bowel are found? (3)
LymphomasCarcinoid tumoursCarcinomas