DKA & HHS Flashcards
What is the criteria for diagnosis HHS?
Dehydration Osmolality >320 mosmol/kg Hyperglycaemia > 30 mmol/l Minimal ketonaemia <3 mmol/l Minimal acidosis - pH >7.3, bicarbonates >15mmol/l
What investigations do you need to do in a patient with suspected HHS?
FBC U&E LFTs Plasma osmolality Venous blood gas - pH, bicarbonate, lactate Plasma glucose Blood ketones HbA1c Blood cultures if septic/febrile Urinalysis ECG, CXR
How do you calculate plasma osmolality?
2Na + glucose + urea
What are the principles of initial management of HHS?
- LMWH prophylaxis
- Fluid hydration - 0.9% sodium chloride
- Insulin treatment - only if meets criteria
- K+ replaced
- Avoid hypoglycaemia - glucose infusion if required
What fluid regimen should you follow in HHS?
0.9% sodium chloride
1,22,44,66,888
1L in 1 hr 1L in 2 hr 1L in 2 hr 1L in 4hr 1L in 4hr 1L in 6hr 1L in 6hr 1L in 8hr 1L in 8hr 1L in 8hr
When would you prescribe insulin in the treatment of HHS?
- Blood glucose failed to fall further after initial fluid resuscitation
- Blood ketones > 1mmol/l
How much K+ would you add to the fluids in HHS management?
Once urine starts to flow…
If > 5.5 None
If 3.5-5.5 40 mmol/l
If <3.5 seek help as additional K+ needed
What CBG should you aim for in patients with HHS and why?
10-15 mmol/l for first 24hours
Avoid cerebral oedema
How can you avoid hypoglycaemia in patients with HHS?
If CBG <14 mmol/l, start glucose infusion while continuing with fluids.
After initial management of HHS, what must you do?
Catheterise - measure fluid balance
Look for cause - sepsis, MI, drugs, bowel infarct
How does HHS present?
Generalised weakness, leg cramps Visual impairment Nausea + vomiting (less than DKA) Confusion Focal neurological symptoms -confused with stroke Seizures (25%)
What signs would you see in HHS?
Tachycardia
Hypotension
Raised RR
What are differential diagnosis for HHS?
Delirium (older patients)
Acute poisoning
Metabolic acidosis
What is the mechanism behind DKA?
Starvation state where lipids are broken down to form FFA which are substrates for ketones.
FFA also substrates for gluconeogenesis, causing hyperglycaemia.
High glucose but no insulin so cannot be taken into cells.
Severe acidosis and hyperglycaemia combination is dangerous.
How does DKA present?
Develops within 24 hours Usually T1DM Drowsiness Vomiting Dehydration Non-specific abdo pain Altered mental state- coma if severe Kussmual respiration (to compensate for acidosis)
