Day 1 - Diabetic Ketoacidosis
Pillars of management:
Volume resuscitation
Insulin to correct anion gap
Correction of electrolyte abnormalities
Treatment of precipitating cause
Treatment:
Potassium replacement - total body deficit despite normal or elevated serum K+
Do NOT start insulin if less than 3.3 - replete K+ then proceed
If patient is anuric, volume resuscitate and ensure urine output prior to K+ administration
Volume resuscitation
Severe volume depletion (6-8 L) given osmotic diuresis, vomiting and decreased oral intake
Start by giving fluid boluses 1-2L for the first 1-2hrs followed by
500 mL/hr for 4 hours then decrease to 250 mL/hr thereafter
*Ensure caution in patients with CHF or renal failure, and insert a urinary catheter to monitor accurate urine output
Insulin infusion
Insulin is used to stop ketone production & close anion gap, therefore infusion is adjusted to anion gap
Start at 0.1units/kg/hr
No need to use an insulin bolus, as this has not been shown to improve outcomes
You only consider stopping the insulin infusion in cases where potassium is much less than 3.3
Avoid decreasing blood glucose by more than 5 mmol/L/hr, adjust insulin infusion accordingly
Target glucose between 12-15 mmol/L
If glucose drops below 15, add D5W to your fluids to compensate
Never stop your insulin infusion because of drop in blood glucose. Instead add dextrose to your fluids
4. Serum osmolality - Cerebral edema is of concern if osmolality or sodium are corrected too quickly
Avoid correcting glucose by more than 5mmol/L/hr or plasma osmolality faster than 3 mOSm/kg/h
*Hyperglycemia can create pseudo-hyponatremia - correct Na by 3 mmol/L for every increase in glucose of 10 above 10 mmol/L
If the patient has hypernatremia, drop the sodium content of your fluids by using 1/2NS instead
5. Sodium Bicarbonate
May only be beneficial if the pH is less than 6.9
In these cases, you can give 1 amp of sodium bicarbonate in 200 mL D5W over 1 hour and repeat every 2 hours until pH is more than 7
Avoid giving bicarbonate if K is less than 3.3 as this can exacerbate hypokalemia
6. Precipitating factors
Must be addressed for management to be successful
Consider: insulin non-adherence (socioeconomic factors, sick day, etc), infection, myocardial infarction, stroke, intoxication, exogenous steroids, etc.
Involve appropriate services, ie. surgical consultation, cardiology, when appropriate
7. Transition to subcutaneous insulin when:
AG closes
BG < 15mM
Insulin requirements are 0.5-1 unit per hour or requiring near baseline insulin requirements
Patient is hungry and tolerating PO intake
Patient can be closely monitored during the transition
Overlap IV insulin with subcutaneous rapid acting insulin for 1-2 hours before stopping your insulin infusion altogether
Investigations:
Glucose - capillary if accurate, but may require serum if severely elevated
*Consider euglycemic DKA in patients with anion gap but normal glucose - seen often in patients on SGLT2 inhibitors or presenting with starvation ketosis
Electrolytes & serum bicarbonate to calculate anion gap
AG = sodium - [chloride + bicarbonate]
Venous blood gas to assess for metabolic acidosis
β-hydroxybutarate
May be negative depending on assay and stage of metabolites
Identification of underlying cause
ECG & troponin
Chest x-ray
Blood cultures, urinalysis
Osmolar gap for co-ingestions
βHCG if childbearing age