Paeds DKA

Question 1

What are the important principles underpinning DKA management?

Answer 1

Consider underlying cause: non-compliance, new diagnosis, sepsis, other illness

Prevent, seek and treat complications: shock, hypokalaemia, cerebral oedema (overaggressive fluid resus)

Question 2

How do you determine the fluids required for a paediatric DKA patient?

Answer 2

Estimate deficit + maintenance.

Deficit = % dehydrated x 10 x weight in kg (eg. 5% dehydration = 50 ml/kg)

Maintenance = use 100/50/20 rule (per day) or 4/2/1 (per hour)

Correct over 48 hours using normal saline.

Question 3

Describe how you would sort out the insulin for DKA patients.

Answer 3

Start at 0.05-1 unit/kg/hr aiming for a BSL fall of <5 mmol/L/hr.

Once BSL <17, change fluids to 0.45% saline + 5% dextrose from 0.9% normal saline.

Question 4

Describe how you would manage potassium in DKA.

Answer 4

Add KCl 40 mmol/L of maintenance fluid and titrate the KCl replacement, aiming for a [K+] of 4-5 mmol/L. DO not add K+ to bolus fluids.

Question 5

What would you do if you suspect a DKA patient has cerebral oedema?

Answer 5

Stop fluids, give mannitol 0.5-1 g/kg IV and consider need for intubation + ventilation + CT brain

Question 6

What is the key life threatening complication of DKA?

Answer 6

Cerebral oedema

Question 7

What are the biochemical criteria for DKA?

Answer 7

(1) Serum glucose >11 mmol/L, (2) Venous pH <7.3 or bicarb <15, (3) Presence of ketonaemia/ketonuria

Question 8

What condition may children who have hyperglycaemia and ALOC but no ketonaemia and normal pH have?

Answer 8

Hyperglycaemic-hyperosmolar non-ketotic coma

Question 9

At what percent of dehydration do patients present with shock?

Answer 9

> 7%

Question 10

Differentiate mild, moderate and severe DKA.

Answer 10

Mild = pH <7.3, bicarb <15
Mod = pH <7.2, bicarb <10
Severe = pH <7.1, bicarb <5

Question 11

What are the goals with treatment for DKA?

Answer 11

(1) Correct dehydration
(2) Reverse ketosis, correct acidosis and glucose
(3) Monitor for the complications of DKA
(4) Identify and treat the possible precipitating cause

Question 12

How do you correct sodium for hyperglycaemia?

Answer 12

Corrected Na = measured Na + 0.3 x (glucose - 5.5) mmol/L

Question 13

If the sodium does not rise as the glucose falls during the treatment of DKA (or hyponatraemia develops) what could be the cause of this?

Answer 13

Excessive fluid correction

Question 14

How do you make up the insulin infusion for DKA?

Answer 14

50 units of clear/rapid acting insulin (Actrapid or Huulin) to 49.5 ml of 0.9% sodium chloride to form a 1 unit/ml solution

Question 15

What are the most important complications of DKA?

Answer 15

Cerebral oedema, hypoglycaemia, hypo/hyperkalaemia, hypo/hypernatraemia, aspiration (if obtunded)

Question 16

What are the risk factors for cerebral oedema in DKA?

Answer 16

First presentation diabetes, long hx of poor control, age <5 years old

Question 17

What can be said about the timing and presence of cerebral oedema with DKA?

Answer 17

Some degree of subclinical swelling is present during most episodes of DKA. Clinical cerebral oedema occurs suddenly, usually between 6-12 hours after starting therapy (range 2-24 hours).

Question 18

What are the signs for cerebral oedema in DKA?

Answer 18

Early: headache, irritability, lethargy, vomiting.
Later: depressed conscious state, incontinence, thermal instability
Very Late: bradycardia, increased BP, respiratory impairment

Question 19

How is mannitol given in suspected cerebral oedema in DKA?

Answer 19

Mannitol 20% (0.2 g/ml). Dose of 0.5 g/kg IV over 20 minutes (dose range: 0.25-1 g/kg). Repeat if no improvement in 30 mins.

Question 20

What is the treatment for hypoglycaemia in children w/ DKA?

Answer 20

2 ml/kg of 10% glucose IV bolus + change rehydration fluids to include 10% glucose w/ potassium chloride if required. Continue the insulin.

Question 21

How much sugar/carb does a 60 ml juice have?

Answer 21

5 grams (for children <25 kg) - this can be given orally for hypoglycaemia

Question 22

In spite maintenance 10% glucose a DKA patient’s BSLs are still dropping, what should you do?

Answer 22

Do not stop the insulin infusion, however reduce from 0.1 unit/kg/hr to 0.05 units/kg/hr. And even down to 0.03 units/kg/hr

Question 23

If the acidosis in a DKA patient is not correcting, what is the ddx?

Answer 23

Insufficient insulin to switch off ketosis, inadequate rehydration, sepsis, hyperchloraemia acidosis (due to IVT), salicylates/other substances that cause metabolic acidosis

Question 24

What are important points about bicarbonate in DKA?

Answer 24

Only appropriate in children with life-threatening hyperkalaemia. May cause paradoxical CNS acidosis and is associated with increased risk of cerebral oedema.

Question 25

How would you dose bicarbonate in DKA with life-threatening hyperkalaemia?

Answer 25

Bicarb dose = 0.15 x body weight x base deficit. Given over 30-60 minutes.