Week 23 - Diabetes Type 1 and 2 and all complications! Flashcards
what is type one diabetes
where the pancreas stops being able to produce adequate insulin.
what is the result of not having insulin
the cells of the body cannot absorb glucose from the blood and use it as fuel.
therefore the cells think there is no glucose available, meanwhile the glucose level in the blood keeps rising causing hyperglycaemia
what is the classic triad of symptoms seen in type one diabetes (hyperglycaemia)
- polyuria (excessive urine)
- polydipsia (excessive thirst)
- weight loss (mainly through dehydration)
how else may patients present
with ketoacidosis
the body ideally wants to keep blood glucose concentration at what range
The body ideally wants to keep blood glucose concentration between 4.4 – 6.1 mmol/L.
where is insulin produced and what cell
the beta cells in the islets of langerhans in the pancreas
what are the two ways that insulin acts on the blood sugar levels
Firstly, it causes cells in the body to absorb glucose from the blood and use it as fuel. Secondly, it causes muscle and liver cells to absorb glucose from the blood and store it as glycogen in a process called glycogenesis. Firstly, it causes cells in the body to absorb glucose from the blood and use it as fuel.
Secondly, it causes muscle and liver cells to absorb glucose from the blood and store it as glycogen in a process called glycogenesis.
what is glucagon and what is its role in glucose metabolism
Glucagon is a hormone produced by the alpha cells in the Islets of Langerhans in the pancreas.
It is released in response to low blood sugar levels and stress and works to increase blood sugar levels. It tells the liver to break down stored glycogen and release it into the blood as glucose in a process called glycogenolysis. It also tells the liver to convert proteins and fats into glucose in a process called gluconeogenesis.
when does ketogenesis occur
when there is insufficient glucose supply and glycogen stores are exhausted, such as in prolonged fasting
what is converted to ketones and by what
fatty acids are converted to ketones by the liver
what is the characteristic about ketosis
acetone smell to their breath
what is diabetic ketoacidosis
The kidneys buffer ketone acids (ketones) in healthy people, so the blood does not become acidotic. When type 1 diabetes causes extreme hyperglycaemic ketosis, this results in a life-threatening metabolic acidosis. This is called diabetic ketoacidosis.
when does diabetic ketoacidosis occur
as a consequence of inadequate insulin
what are the three key features of diabetic ketoacidosis
ketoacidosis
dehydration
potassium imbalance
what happens in dehydration
high blood glucose levels overwhelm the kidneys, and glucose leaks into the urine. the glucose in the urine draws water out by osmotic diuresis. this causes increased urine production and resulting in severe dehydration
what does dehydration result in
polydipsia - excessive thirst
what does insulin normally do to potassium
normally drives potassium into cells.
what happens with insulin to potassium and what does this mean for the potassium imbalance
without insulin, potassium is not added to and stored in cells.
the serum potassium can be high or normal as the kidneys balance blood potassium with the potassium excreted into the urine
why is total body potassium low
because no potassium is stored in the cells
what call happen to the potassium imbalance when patients are treated with insulin
patients can develop severe hypokalaemia very quickly leading to severe arrhythmias
what are the symptoms of diabetic ketoacidosis
Polyuria
Polydipsia
Nausea and vomiting
Acetone smell to their breath
Dehydration
Weight loss
Hypotension (low blood pressure)
Altered consciousness
what may diabetic ketoacidosis be triggered by
an underlying infection.
what does a diagnosis of diabetic ketoacidosis require
Hyperglycaemia (e.g., blood glucose above 11 mmol/L)
Ketosis (e.g., blood ketones above 3 mmol/L)
Acidosis (e.g., pH below 7.3)
what is the priority treatment in diabetic ketoacidosis
fluid resuscitation to correct dehydration, electrolyte imbalance and acodisosi
what is fluid resuscitation followed by in diabetic ketoacidosis treatment
insulin infusion to get the cells to start taking up and using glucose and stop producing ketones
what is the pneumonic used for diabetic ketoacidosis treatment
FIG PICK
what does FIG PICK stand for
F – Fluids – IV fluid resuscitation with normal saline (e.g., 1 litre in the first hour, followed by 1 litre every 2 hours)
I – Insulin – fixed rate insulin infusion (e.g., Actrapid at 0.1 units/kg/hour)
G – Glucose – closely monitor blood glucose and add a glucose infusion when it is less than 14 mmol/L
P – Potassium – add potassium to IV fluids and monitor closely (e.g., every hour initially)
I – Infection – treat underlying triggers such as infection
C – Chart fluid balance
K – Ketones – monitor blood ketones, pH and bicarbonate
what should happen before stopping the insulin and fluid infusions in diabetic ketoacidosis
Ketosis and acidosis should have resolved
They should be eating and drinking
They should have started their regular subcutaneous insulin
TOM TIP: Remember, under normal circumstances, the rate of potassium infusion should not exceed 10 mmol/hour, as there is a risk of inducing an arrhythmia or cardiac arrest. In DKA, rates up to 20 mmol/hour may be used. Higher rates are only used in specific scenarios under expert supervision with cardiac monitoring and through a central line (rather than a peripheral cannula).
what are the autoantibodies seen in type one diabetes
Anti-islet cell antibodies
Anti-GAD antibodies
Anti-insulin antibodies
what is a measure of insulin production and how does it work
Serum C‑peptide is a measure of insulin production. It is low with low insulin production and high with high insulin production.
what does long term management of type one diabetes involve
Subcutaneous insulin
Monitoring dietary carbohydrate intake
Monitoring blood sugar levels upon waking, at each meal and before bed
Monitoring for and managing complications, both short and long term
what does a basal bolus regime of insulin involve a combination of:
background, long acting insulin injected once a day
short acting insulin injected 30 mins before consuming carbohydrates
what are insulin pumps
small devices that continuously infuse insulin at different rates to control blood sugar levels
what are insulin pumps alternative to
a basal bolus regime
what are the disadvantages of insulin pumps
Difficulties learning to use the pump
Having it attached at all times
Blockages in the infusion set
A small risk of infection
what are tethered pumps
devices with replaceable infusion sets and insulin. they are usually attached to the patient’s belt or around the waist with a tube connecting the pump to the insertion site. the controls for the infusion are on the pump itself
what are patch pumps
Patch pumps sit directly on the skin without any visible tubes. When they run out of insulin, the entire patch pump is disposed of, and a new pump is attached. A separate remote usually controls patch pumps.
what does Hb1AC measure
glycated haemoglobin which is how much glucose is attached to the haemoglobin molecule.
This reflects the average glucose level over the previous 2-3 months (red blood cells have a lifespan of about 4 months). It is measured every 3 to 6 months to track the average sugar levels. It is a lab test.
describe capillary blood glucose
Capillary blood glucose (finger-prick test) can be measured using a blood glucose monitor, giving an immediate result. Patients with type 1 and type 2 diabetes rely on these machines for self-monitoring their sugar levels.
what is continuous glucose monitors
similar to flash glucose monitors in that a sensor on the skin monitors the sugar level in the interstitial fluid
However, continuous glucose monitors send the readings over bluetooth and do not require the patient to scan the sensor.
what is a closed loop system for diabetes type one
also called an artificial pancreas, involves a combination of a continuous glucose monitor and an insulin pump. The devices communicate to automatically adjust the insulin based on the glucose readings. Patients still need to input their carbohydrate intake and adjust the system to account for strenuous exercise.
what are symptoms of hypoglycaemia
Typical symptoms are hunger, tremor, sweating, irritability, dizziness and pallor. More severe hypoglycaemia will lead to reduced consciousness, coma and death unless treated.
what does hypoglycaemia need to be treated initially with
rapid acting glucose
high sugary energy drink
after treating hypoglycaemia with rapid acting glucose, what is the next step
Once the blood glucose improves, they consume slower-acting carbohydrates (e.g., biscuits or toast) to prevent it from dropping again. Options for treating severe hypoglycaemia are IV dextrose and intramuscular glucagon.
what are the macrovascular complications of diabetes type one
Coronary artery disease is a significant cause of death in diabetics
Peripheral ischaemia causes poor skin healing and diabetic foot ulcers
Stroke
Hypertension
what are the microvascular complications of diabetes type one
Peripheral neuropathy
Retinopathy
Kidney disease, particularly glomerulosclerosis
what are the infection-related complications of diabetes type one
Urinary tract infections
Pneumonia
Skin and soft tissue infections, particularly in the feet
Fungal infections, particularly oral and vaginal candidiasis
what is type two diabetes
a condition where there is a combination of insulin resistance and reduced insulin production causing persistently high blood sugar levels
what is the simple pathophysiology behind diabetes type 2
Repeated exposure to glucose and insulin makes the cells in the body resistant to the effects of insulin. More and more insulin is required to stimulate the cells to take up and use glucose. Over time, the pancreas becomes fatigued and damaged by producing so much insulin, and the insulin output is reduced.
A high carbohydrate diet combined with insulin resistance and reduced pancreatic function leads to chronic high blood glucose levels (hyperglycaemia). Chronic hyperglycaemia leads to microvascular, macrovascular and infectious complications, as described in the type 1 diabetes section.
what are the non-modifiable risk factors for type two diabetes
older age
ethnicity - black
family history
what are the modifiable risk factors for type two diabetes
Obesity
Sedentary lifestyle
High carbohydrate (particularly sugar) diet
what is the presentation of diabetes
tiredness, polyuria, polydipsia, unintentional weight loss, opportunistic infections, slow wound healing, glucose in urine
