[Endo] Diabetic Ketoacidosis Flashcards
what is diabetic ketoacidosis (DKA)?
diabetic emergency typically seen in T1DM and to a lesser extent, T2DM
what is DKA defined as?
- hyperglycaemia >11 mmol/L
- ketones ≥3 mmol/L (blood) or ≥2+ in urine (serum more accurate)
- acidaemia pH <7.1 or bicarb <15 mmol (caused by ketone bodies)
what is the 1st line ix for DKA?
venous blood gas and serum ketones
what are the initial ix for DKA?
- blood ketones
- capillary blood glucose
- venous blood gas
- FBC, U+E, blood cultures
- MSU (midstream specimen urine)
- ECG
- CXR (if indicated)
- continuous cardiac monitoring
you think a pt has DKA. you perform an A-E assessment. what next?
give 1L 0.9% NaCl over 1 hour (stat if systolic BP <90mmHg)
you gave 1L 0.9% NaCl, what next?
commence Fixed Rate Insulin Infusion (FRII) 0.1 units/kg/hour of Actarapid / Humulin S
until when should you continue FRII for?
until blood ketones <0.6, pH >7.3+ / HCO3 >18
what do you do when glucose <14 mmol/L?
replace with 10% glucose
what is the fluid mx like for DKA over 1-12 hours?
0.9% NaCl (1L) + KCl over 2 h ↓ 0.9% NaCl (1L) + KCl over 2 h ↓ 0.9% NaCl (1L) + KCl over 4 h ↓ 0.9% NaCl (1L) + KCl over 4 h ↓ 0.9% NaCl (1L) + KCl over 6 h
what should be assessed hourly?
blood ketones and CBG
- blood ketones should fall by 0.5 mmol/L/hr
- bicarb should rise by 0.5 mmol/L/hr
- blood glucose should fall by 3.0 mmol/L/hr
if not: increase FRII by 1.0 unit/hr
how often should you check VBG for pH, HCO3 and K+?
at 60 mins
at 2 hours
and then 2 hourly
what should you assess at 12 hours?
cardiovascular status
do you need to replace potassium if K+ >5.5?
no
do you need to replace potassium if K+ 3.5-5.5?
yes + 40mmol to NaCl
what do you do if K+ <3.5?
senior review, may need to go to HDU
when should DKA resolve if appropriately treated?
within 12-24 hours
if the pt is not eating/drinking, what do you do?
continue IV fluids and commence VRII
if the pt is eating/drinking, what do you do?
commence subcutaneous insulin* 1 hour before stopping FRII
*involve diabetes specialist team for advice
what should you treat in DKA?
the precipitating cause
what complications do you need to reassess for in DKA?
- hypoglycaemia
- hypo/hyperkalaemia
- pulmonary and cerebral oedema
what are the signs of hypokalaemia?
- muscle weakness
- hypotonia
- hyporeflexia
- cramps
- tetany
what are the causes of hypokalaemia?
- drugs (K+ wasting diuretics, insulin, steroids, terbutaline)
- vomiting and diarrhoea
- Conn’s
- Cushing’s
- renal tubular acidosis (type 1)
- hypomagnesemia
what are the ECG changes seen in hypokalaemia?
- small T waves
- prominent U waves
- depressed ST segment
- prolonged PR interval
what is the rx for hypokalaemia?
- KCl
- sando-K
- stop K+ wasting drugs
what are the signs of hyperkalaemia?
- chest pain
- palpitations
- tinnitus
- light headedness
- tachycardia
what are the causes of hyperkalaemia?
- AKI
- drugs (ACEi, K+ sparing diuretics, cyclosporin, tacrolimus)
- pseudohypokalaemia
- metabolic acidosis
- renal tubular acidosis (type 4)
- Addison’s
young pt treated for DKA with reduced GCS, severe acidosis and relative bradycardia. dx?
iatrogenic cerebral oedema
metformin use and impaired renal function and acidosis. dx?
metformin induced lactic acidosis
elderly T2DM pt, hyperglycaemia and hypernatraemia. dx?
hyperosmolar hyperglycaemic state
why is the initial rx of DKA with 0.9% NaCl fluid bolus?
these pts are significantly dehydrated
what is key to avoiding complications in DKA?
careful mx of glucose and potassium
what do you do if the DKA does not resolve within 24 hours?
senior/critical care input
