Flashcards in Week 101 - Diarrhoea Deck (81)
What is considered a slow capillary refill time?
What are the signs of moderate dehydration?
What are the signs of severe dehydration?
• Unable to drink
What is the definition of diarrhoea?
3 or more loose/watery stools within 24 hours.
What are the four causes of diarrhoea?
What is infective diarrhoea?
This is diarrhoea caused by an infective agent. It typically has sudden onset and comes with associated fever and cramp-like abdominal pain.
What is Inflammatory diarrhoea?
This is diarrhoea caused by an inflammatory condition such as IBD. Often occurs with a blood stained stool.
What is steatorrhoea?
This is pale, offensive floating stool. It often coincides with weight loss and appetite loss.
• Giardiasis and Coeliac disease.
What is functional diarrhoea?
Small volume and often semi-formed.
What are the two main mechanisms of diarrhoea?
Osmotic and Secretory
What is osmotic diarrhoea?
• This is where there are large amounts of hypertonic substances in the lumen which may be due to substances that can't be digested, general malabsorption.
• Moderate volume
• Stops on fasting
• High osmolality of stool
What is secretory diarrhoea?
• Active secretion of fluid and electrolytes from gut wall which may be due to irritants and hormones.
• High volume
• Continues on fasting (Still secreting)
• Normal osmolality of stool
Which mechanism of diarrhoea is halted by fasting?
Which mechanism of diarrhoea produces high volume of stools?
Which mechanism of diarrhoea produces stools with a high osmolality?
What are the initial investigations for diarrhoea?
Stool sample - Osmolality, microbiology, culture and sensitivity.
What investigation may be needed for persistent diarrhoea?
Sigmoidoscopy and rectal biopsy.
What is the initial stage of treatment for diarrhoea?
Assess fluid status and rehydrate if required.
Once fluid status is assessed and managed how should acute diarrhoea be managed?
• Treat cause - Antibiotics/ stop drugs causing.
• Treat diarrhoea - Loperamide - Opioid agonist, decreases motility and increase anal sphincter tone.
• (Infective diarrhoea is often self-limiting so let it run it's course)
101 Diarrhoea: What are the three steps of treatment for acute diarrhoea?
1) Replace fluids.
2) Address the underlying cause.
3) Stop Diarrhoea.
101 Diarrhoea: Describe (briefly) how oral rehydration solutions work?
They are composed of glucose and sodium, which get actively pumped into the cell, this causes water to follow and the glucose and sodium are then excreted.
101 Diarrhoea: What is the main drug used to stop acute diarrhoea? What class is it?
Loperamide, anti-motility drug.
101 Diarrhoea: What is the mechanism of Loperamide?
It is an opioid receptor agonist which causes decreased motility of the bowel and increases the tone of the anal sphincter.
101 Diarrhoea: What is the role of Racecadotril and what is it's mechanism?
Treatment of acute diarrhoea. Inhibits enkephalinase, therefore prolonging the life of enkephalins, which are opioid receptor agonists, causing decreased motility of the bowel.
101 Diarrhoea: How long would you expect a skin pinch on a child abdomens to revert back to normal shape in a healthy child?
Immediate, 1s=slow, ≥2s = very slow.
101 Diarrhoea: In what part of the bowel does the majority of fluid resorption take place?
101 Diarrhoea: By which part of the bowel is the absorption of <95% of macronutrients completed by?
101 Diarrhoea: Which part of the bowel has specialised transport mechanisms for bile acids and Vitamin B12-IF?
101 Diarrhoea: What role does the colon play in nutrient absorption?
Carbohydrate digestion and absorption, enzymes produced by colonic bacteria break the carbohydrates into short-chain fatty acids which can then be absorbed.