High Glucose States Flashcards
Diabetic Ketoacidosis
Diabetic Ketoacidosis (DKA) is a disordered metabolic state that usually occurs in the context of an absolute or relative insulin deficiency accompanied by an increase in the counter-regulatory hormones i.e. glucagon, adrenaline, cortisol and growth hormone
Why do people die from diabetic ketoacidosis?
Adults: Hypokalaemia, Aspiration Pneumonia, ARDS, Co-morbidities Children: Cerebral oedema
Common precipitants of DKA
infections (20 to 25%) – may be an over-estimate
Illicit drugs and alcohol (10 to 15%)
non-compliance with treatment (45 to 50%) – may be under-estimate
newly diagnosed diabetes (25% and falling?)
Diabetic Ketoacidosis Diagnosis
Ketonaemia > 3mmol /L, or significant ketonuria (>2+ on standard urine stick)
Blood glucose > 11.0 mmol /L or known diabetes (NB euglycaemic DKA)
Bicarbonate < 15 mmol /L or venous pH < 7.3
Classical biochemistry DKA
Glucose -Median level around 40 mmol/L -From 10 [‘euglycaemic ketosis’] to 100 mmol/L Potassium -Usually raised above 5.5 mmol/L -Beware the low normal Creatinine: often raised Sodium: often reduced Raised lactate is very common
Management of DKA
Replace losses Fluid Initially with 0.9% sodium chloride Glucose falls to about 15, switch to dextrose Insulin Potassium Phosphate [rarely] and Bicarbonate [almost never] replaced Address risks ? is a naso-gastric tube required? Monitor K+ Prescribe prophylactic LMWH Source sepsis: CXR, Blood Culture, MSSU +/- viral titres, etc
Urine ketone testing
Measures acetoacetate
Indicates levels of ketones 2-4 hours previously
Ketonuria persists after clinical improvement due to mobilisation of ketones from fat tissue
Blood ketone testing
Optium meter
Measures beta-hydroxybutyrate
Meter range 0 - 8mmol/L
< 0.6 mmol/L normal
When should you admit someone to hospital for DKA
Unable to tolerate oral fluids Persistent vomiting Persistent hyperglycaemia Persistent positive/increasing levels of ketones Abdominal pain / breathlessness
Clearance of lactate?
Clearance requires hepatic uptake and aerobic conversion to pyruvate then glucose
Where does lactate come from?
Lactate comes from red cells, skeletal muscle, brain and renal medulla
Type A lactic acidosis
Associated with tissue hypoxaemia Infarcted tissue, eg ischaemic bowel Cardiogenic shock Hypovolaemic shock Sepsis [endotoxic shock] Haemorrhage
Type B lactic acidosis
May occur in Liver disease
Associated with drug therapy, eg Metformin
Associated with Diabetes
10% of cases of DKA associated with lactate >5 mmol/L.
With Metformin usually in severe illness states or renal failure
Also consider rare inherited metabolic conditions if well and non-diabetic
Which type of lactic acidosis is associated with diabetes?
Type B lactic acidosis
also associated with metformin
Normal range of lactate
0.6 - 1.2. is normal range for lactate
