Diabetic Emergencies Flashcards
Ketone bodies are formed where?
Liver mitochondria
Ketone bodies are derived from which chemical?
Acetyl-CoA
DKA is rare in T2DM, why?
Insulin prevents ketone body overload (by inhibiting lipolysis & hence production of acetyl-CoA from fats) and T2DM often have residual insulin
When is Acetyl-CoA diverted into ketone bodies?
When there is no oxaloacetate available for it to enter the TCA
List 3 ketone bodies
1) Acetone
2) Acetoacetic acid
3) Beta-hydrobutyric acid
DKA only occurs in T1DM. True/false?
False
Counter-regulatory hormones are increased/decreased in DKA. True/false?
True
The underlying cause of DKA is…
An absolute or relative insulin deficiency
How does DKA lead to ketogenesis? (3)
1) A lack of insulin increases counter-regulatory hormones.
2) These hormones encourage lipolysis.
3) Fatty acids are brought to the liver, where they are made to ketones for emergency energy.
Blood glucose is usually low/normal/high in DKA?
High (but euglycaemic DKA exists)
On a dipstick, how many +’s would indicate significant ketonuria?
> 2
What 3 factors need to be tested for a diagnosis of DKA to be made?
Ketones in blood, blood glucose, bicarbonate/ pH
Bicarbonate is usually < what in DKA?
<15mmol/L (gives pH <7.3)
Describe the common precipitants of DKA (4)
1) Infection
2) Illicit drugs + alcohol
3) Non-adherence to treatment (majority)
4) Newly diagnosed diabetes
What are the osmotic symptoms of DKA?
Thirst, polyuria, dehydration
What are the ketone symptoms of DKA?
Flushing, vomiting, abdominal pain, Kussmaul’s respiration (although not all patients can smell this), bad taste in mouth
Lactate is often raised/lowered in DKA?
Raised
In DKA, a raised amylase is a sign of pancreatitis?
No, it’s often salivary in origin
What’s a cause of death in children with DKA?
Cerebral oedema
What’s a cause of death in adults with DKA? (3)
ARDS, aspiration pneumonia, hypokalaemia.
In the HDU, DKA is managed by fluid replacement initially. Which fluid is given? What is switched to?
0.9% sodium chloride initially, then switch to dextrose once glucose falls to around 15mmol/L
DKA patients should be given potassium and insulin, true/false?
True
In DKA, phosphate and bicarbonate are frequently replaced, true/false?
False
Which ketone type is measured in urine?
Acetoacetate
Ketones in urine lag behind blood ketones by how long?
2-4 hours
After an episode of DKA, it is normal to have persisting ketonuria. True/false?
True (ketones are mobilised from fat tissue)
Hyperglycaemic hyperosmolar syndrome occurs in youth/elderly?
Elderly
HHS often presents in those who’s diabetes is dietary-lone managed. True/false?
True
HHS is usually preceded by what event?
High intake of CHOs
HHS can be precipitated by what factors? (2)
1) CV event
2) Sepsis
HHS is defined as which 3 factors being present? (3)
1) Hypovolaemia
2) Hyperglycaemia (BG>30mmol/L without acidosis or ketonaemia)
3) Hyperosmolar
The BG is often higher in HHS than DKA, true or false?
True
HHS presents with significant X impairment.
X = renal
Ketones are raised in HHS higher than DKA. True/false?
False
HHS is commoner in which type of DM?
T2DM
What has higher mortality - DKA or HHS?
HHS
How is HHS treated? (3)
Dietary intervnetion, hypoglycaemic drugs, insulin.
HHS patients should be given insulin faster than those in DKA. True/false?
False (some patients do not even require insulin)
Fluids should be given rapidly in HHS. True/false?
Slowly (risk of overload)
Lactate is produced where (4)
Red blood cells, muscle, brain, renal medulla
Lactate is cleared via the
Liver
Lactate is converted to what?
Pyruvate (then into glucose)
Type A lactic acidosis occurs in response to…
Tissue hypoxia (e.g. infarcted tissue, hypovolaemic shock, sepsis)
Type B lactic acidosis occurs in response to…
Liver disease, diabetes.
Treatment of lactic acidosis (2)
1) Fluids
2) Antibiotics
What is a non-insulin related cause of ketoacidosis?
Alcohol
How is alcoholic ketoacidosis treated? (2)
1) Pabrinex
2) IV fluids (esp. dextrose)
Rarely insulin
What’s the main difference between regular DKA & euglycaemic DKA?
Euglycaemic has a lower BG (<15mmol/L)
What should the HbA1c be before elective surgery is carried out?
<75mmol/L