Confirm diabetic ketoacidosis - pH < 7.3

  • DKA =
    • Ketonaemia > 3.0mmol/L or significant ketonuria (> 2+ on urine sticks)
    • Blood glucose > 11.0mmol/L or known diabetes mellitus
    • Bicarbonate (HCO3-) < 15.0mmol/L and/or venous pH < 7.3
  • hyperosmolar non-ketotic coma in the elderly - may have + or ++  urinary ketones but are not acidotic.


Relative insulin deficiency = ↑Glu, ↓pH and ketonaemia.

↑glucagon, cortisol, catecholamines⇒ ↑ gluconeogenesis ⇒ ↑↑ glucose.

↑ lipolysis ⇒ ↑ free fatty acids - ketogenesis - metab acidosis (3-beta-hydroxybutyrate).

Dehydration 2°: osmotic diuresis and vomiting = electrolyte (K+⇑ or K+⇓) shifts.

Mortality from

  • Children: Cerebral oedema
  • Adults: ⇓K+, ARDS, co-existing sepsis/ AMI etc

Aims and principles

1. Correction of ketoacidosis by

* insulin suppression of ketogenesis

* insulin stimulated entry of glucose into cells (correct ketonaemia)

To achieve this you need to give enough insulin to correct the acidosis. Once the blood glucose falls you will often need to support the insulin with infused dextrose

3. Replace lost fluid and electrolytes

2. Controlled, steady correction of abnormalities 

* aim for glucose fall 3-5 mmol/l/hr only

* allow acidosis to correct as above

Do not consider bicarbonate unless pH < 6.9  If necessary use IL 1.26% solution + 20 mmol KCl 


4. Establish and treat cause

Emergency department management DKA

Initial assessment

For DKA For underlying cause

Urinary ketones

Do not catheterise unless comatose)

Lab serum glucose

Arterial pH, PO2, PCO2, HCO3

U & E



Urinary and blood cultures

Pregnancy test


Patient details / addressograph



D.O.B, Ward

Initial treatment

A)   Replacement of fluid and electrolyte losses

Normal saline +/- KCL until hydration restored
(See documentation chart page 2 )

B)  Correction of ketoacidosis

i.v. insulin +/- 10% dextrose until venous pH > 7.3
  (insulin infusion = 4 - 6 units / hr  =  0.05 - 0.1 units/kg/hr) (See documentation chart page 3)

Aim for glucose fall 3 - 5 mmol/hour only

Do not give bicarbonate unless pH < 6.9 
(SpR or consultant decision only)

C) Treat

Monitoring and continued care


One hour after starting treatment and 

   2 hourly until acidosis corrected

Venous pH

   (in heparinised or ABG syringe)

Plasma glucose

Na+, K+, HCO3-

Record results in documentation chart page 4


Pulse and BP hourly  (Notify Dr if pulse > 100/min or systolic BP < 100 mmHg)

Hourly Neuro Obs if drowsy (Notify Dr. if any fall in GCS or pupillary size)

Capillary blood glucose hourly

Fluid balance chart - with hourly urine output

   Ask patient to pass urine every hour. If no urine after 2 hours - catheter

    Withdraw catheter if good urine output after 1 hour

   Contact Dr if hourly urine < 20 ml or < 30 ml for two consecutive hours

Other measures     NG Tube if vomiting and impairment of conscious level          Coma management as indicated

Recovery phase (this is when most problems occur)

Continue IV regimen with infusion rate constant until acidosis corrected (pH > 7.3), then
If patient eating: Give sc insulin (6 - 8 units Actrapid or patient's normal dose) 30 min before meal. Discontinue i.v. 1 hour after s.c. insulin given and meal eaten
If patient nauseated 
or anorectic:
Continue 10% dextrose infusion (75 ml/hr) with KCL and i.v. insulin at rate necessary to control blood glucose
When patient eating and drinking normally
Newly diagnosed: Start twice daily Mixtard 30:  8 - 12 units b.d. and adjust dose as necessary
Contact diabetes medical firm and specialist nurses for further management
Known IDDM: Recommence normal insulin and adjust as necessary. Consider temporary use of qds regimen if precipitating factor means that the patient is still unwell 
Monitor with capillary blood glucose and urine testing for ketones before meals and bedtime

Most common errors in management of diabetic ketoacidosis

Insulin pump not connected to patient

Failure to review fluid replacement, particularly in the elderly

Failure to act on results (e.g. serum potassium)

Loss of continuity or attention in recovery phase

Stopping IV insulin before SC given

Failure to identify underlying cause

Print protocol (including documentation sheet and insulin sliding scale)