Diabetes - Pathophysiology and Pharmacology Flashcards
What are the nonmodifiable risks of developing diabetes?
Genetics (family)
Age
Gender
Post menopausal
What are the modifiable risks of developing diabetes?
Smoking Hypertension Dyslipidaemia Obesity Physical inactivity Excess alcohol Stress
What is diabetes mellitus and its symptoms?
A disorder of the pancreas
Inadequate insulin for carbohydrate metabolism
What is diabetes insipidus (rare) and its symptoms?
Disorder of the endocrine system
Inadequate anti-diuretic hormone (ADH)
Blood glucose levels are normal
Excessive thirst
Excessive production of dilute urine
What is the reason for diabetes mellitus resulting to inadequate insulin for carbohydrate metabolism?
Glucose absorbed from the gastrointestinal tract cannot be metabolised or stored and so reaches higher than normal levels in the bloodstream
How big is the pancreas in length?
12-15cm long
Where does the pancreas lie in the body?
lies in the epigastric and left of the hypochondriac region
Where does the head of the pancreas lie?
It curves into the shape of the duodenum
Where does the body of the pancreas lie?
Behind the stomach
Where does the tail of the pancreas lie?
In front of left kidney
What space is the pancreas located in?
Retroperitoneal space
What is unique about the pancreas?
It is both endocrine and exocrine
What is the exocrine function of the pancreas?
Digestive enzymes released into duodenum via ducts
What is the endocrine function of the pancreas?
Insulin and glucagon directly into the bloodstream
What are the three cells that the Islets of Langerhaans contains?
Alpha cells
Beta cells
Delta cells
F cells
What is the role of alpha cells?
(Unaffected in diabetics) Secretes the hormone glucagon which raises blood glucose levels
What is the role of the beta cells?
Secretes the hormone insulin which lowers blood glucose levels
What is the role of the delta cells?
Secretes growth hormone inhibiting cells (GHIH) or somatostatin, which inhibits secretion of insulin and glucagon
What is the role of the F cells?
Secretes pancreatic polypeptide which regulates digestive enzymes
What is the process called where glucose is regulated?
Negative feedback
What are the effects of glucagon release?
Stimulates the liver to breakdown glycogen to be released into the blood as glucose
Activates gluconeogenesis which is the conversion of amino acids into glucose
Breakdown stored fat (triglyceride) into fatty acids for use as fuel by cells
What is gluconeogenesis?
Conversion of amino acids into glucose
What are the effects of insulin release?
Conversion of glucose into glycogen for storage in the liver and muscles (glycogenesis)
Accelerates the transport of glucose from blood into cells (especially skeletal muscle)
Allows entry of amino acids into cells and synthesises proteins
Converts glucose into fatty acids (lipogenesis)
What is glycogenesis?
Conversion of glucose into glycogen for storage in the liver and muscles
What is glycogenolysis?
Breakdown of glycogen into glucose
How does the binding of insulin result to glucose entering the cell?
Insulin binds to complimentary receptor on cell
Opens channel for glucose to enter through
What are the different type of Mellitus?
Type 1 (IDDM) Type 2 (NIDDM)
What is Diabetes Mellitus Type 1 (Insulin Dependent Diabetes Mellitus)?
More common in children and young adults
Sudden onset
Deficiency/absence of insulin
Treated with insulin
What is Diabetes Mellitus Type 2 (Non-insulin Dependent Diabetes Mellitus)?
More common in the elderly, late onset
Normally obese
Diet controlled with tablets (can be insulin)
How would you treat Type 1 diabetes?
Absolute deficiency of insulin
Regular injections required to prevent death
What causes Type 1 diabetes?
Autoimmune genetic disorder where pancreatic beta cells are destroyed
What is the metabolism of untreated Type 1 (IDDM)?
Insulin not present to aid entry of glucose into cells
Cells instead use fatty acids to produce adenosine triphosphate (ATP)
By-products of fatty acid catabolism are organic acids called ketones
Ketone bodies form acidosis which lower pH of the blood and result in death
By-product of ketones is acetone smell on breath
What is ketones?
By-products of fatty acid catabolism of organic acids
What are some common types of insulin?
Human Actrapid Human Insulatard ge Human Mixtard 30 ge Human Monotard Human Ultratard Human Velosulin Humulin 1 Humulin Lente Humulin M1 Humulin S Humulin Zn Hypurin Human Actrapid Penfill (pen) Human Insulatard Penfill (pen) Human Mixtard 10 Penfill (pen)
What is the cause of Type 2 diabetes?
Cells in the body are less sensitive to insulin probably through downregulation of insulin receptors
What are the three oral hypoglycaemic agents?
Biguanides
Sulfonylureas
Alpha-Biguanides
What is the role of the oral agent Biguanides?
Stops the liver making extra sugar when it is not needed
Increases uptake of glucose by cells
What is the role of the oral agent Sulfonylureas?
Helps pancreas make extra insulin
What is the role of the oral agent Alpha-Biguanides?
These are inhibitors that slow the digestion of starches
What is the role of the drug called Sulphonylureas?
Helps pancreas produce more insulin
What are the four Sulphonylureas that helps with increased production of insulin?
Gliclazide
Glibenclamide
Tolbutamide
Chlorpropamide
What is the only form of Biguanide available?
Metformin
When is the use of Biguanide contraindicated?
Renal impairment
Risk of lactic acidosis in hepatic/respiratory and cardiac failure
What are some causes of hypoglycaemia?
Overdose of insulin Not enough food or delay in food intake Overdose of medication Too much exercise Alcohol Pregnancy Gastrointestinal disturbances (D&V) Recent illness
What are some causes of hyperglycaemia?
Undiagnosed diabetes
Incorrect medication
Inadequate adjustment to dose of insulin during illness
What are the symptoms of hyperglycaemia?
Polyuria
Polydipsia
Polyphagia
What is polyuria?
Excessive urine
What is polydipsia?
Excessive thirst
What is polyphagia?
Excessive eating
What is the onset of hypoglycaemia?
Sudden and rapid - minutes
What is the onset of hyperglycaemia?
Gradual - hours or days
What happens to the skin in response to hypoglycaemia?
Profuse sweating/pale
What happens to the skin in response to hyperglycaemia?
Dry and flushed
What are the resps like for hypoglycaemia?
Normal to shallow
What are the resps like for hyperglycaemia?
Deep and sighing (Kaussmauls)
What is Kaussmauls?
Deep, laboured breathing often associated with metabolic acidosis, particularly diabetic ketoacidosis but also kidney failure
Refers to high pressure in the jugular vein when a person inhales
What is the pulse like for someone with hypoglycaemia?
Fast and full
What is the pulse like for someone with hyperglycaemia?
Fast and weak
What would the BP be like for someone with hypoglycaemia?
Normal
What would the BP be like for someone with hyperglycaemia?
Low
What is normal blood sugar levels?
4-7mmol/l but 4-5.4mmol/l is without food consumption
What is the breath like for hypoglycaemia?
No odour
What is the breath like for hyperglycaemia?
Sweet/fruity
What is the food intake like for hypoglycaemia?
Low
What is the food intake like for hyperglycaemia?
High
What is the insulin level like for hypoglycaemia?
Excessive
What is the insulin level like for hyperglycaemia?
Insufficient
What are the symptoms for hypoglycaemia?
Hunger Headache Dizzy Confused Seizures Aggressive
What are the symptoms of hyperglycaemia?
Pain Nausea Fever Vomiting Thirst Drowsiness Low BP
How would you pre-hospitally manage hypoglycaemia?
ABCs Oxygen (if hypoxemic) Administer Hypostop (if conscious) Recovery positon Monitor blood glucose IM glucagon Reassurance Consider paramedic assistance for IV glucose
How would you pre-hospitally manage hyperglycaemia?
ABCs Oxygen (if hypoxemic) Recovery position Monitor blood glucose Reassurance Consider paramedic assistance for IV fluid if hypoperfused
On what circumstances should a hypoglycaemic patient be transported to hospital?
Elderly
Are taking oral hypoglycaemic agents, as hypoglycaemia may occur
Have no history and 1st hypo episode
Have blood glucose level greater than 5mmol/l after treatment
Have not returned to normal mental state within 10 minutes of IV glucose (paramedic intervention)
Have been treated with glucagon
Have any additional disorders or complicating factors eg. chest pain, arrhythmias, alcohol, dyspnoea
Exhibits signs of infection (urinary, upper resp tract) and/or unwell
What are some long term complications of diabetes?
Cardiovascular problems
Infection
Renal failure
Optical
What cardiovascular problems can arise from diabetes?
Atheroma leading to Peripheral Vascular Disease and MI
Thickening of arteries leading to retinopathy, renal failure and peripheral neuropathy
Why would renal failure arise from diabetes?
Due to vascular changes
Excessive glucose damages renal blood vessels because its not reabsorbed by the tubules
The remaining glucose raises osmotic pressure, reducing water reabsorption, increased urine volume, electrolyte imbalance, polyuria, hypovolaemia, extreme thirst and polydipsia
Why would an infection arise due to diabetes?
Phagocytic activity may be depressed by insufficient intracellular glucose
Complications occur in areas affected by neuropathy:
Feet when sensation and blood supply impaired
Boils
Carbuncles
Vaginal candidiasis (thrush)
Pyelonephritis (bacterial infection of the kidney)
How would optical issues arise due to diabetes?
Loss of vision due to cataracts as excessive glucose attaches to lens proteins causing cloudiness or damage to blood vessels in the retina
