ABCDE: DKA

Question 1

What triad of features is seen in DKA?

Answer 1

1) Hyperglycaemia (>11mmol/L)

2) Metabolic acidosis (pH <7.3 with bicard <15 mmol/l)

3) Ketosis (urinary ketones >3)

Question 2

What do patients exhibit deep, rapid (Kussmaul) breathing in DKA?

Answer 2

As compensatory mechanism to expel excess CO2.

Question 3

Describe breath in DKA

Answer 3

Ketosis presents with a characteristic sweet, fruity, or acetone odour on the breath.

Question 4

Presentation features of DKA?

Answer 4

1) Hyperglycaemia

2) Metabolic acidosis

3) Ketosis

4) Dehydration: dry mucous membranes, tachycardia, hypotension, and decreased skin turgor

5) Electrolyte imbalances (particularly hypokalaemia)

6) Neurological symptoms e.g. altered mental status

7) Abdo symptoms e.g. pain, N&V

Question 5

What are the 4 main principles of management of DKA?

Answer 5

1) Fluid replacement (most patients with DKA are deplete around 5-8 litres)

2) Fixed rate insulin

3) Correction of electrolyte disturbance

4) Long-acting insulin should be continued, short-acting insulin should be stopped

Question 6

Give fluid replacement regime in DKA for patient with a systolic BP on admission 90mmHg and over?

Answer 6

1) 0.9% sodium chloride 1L over 1st hour

2) 0.9% sodium chloride 1L with potassium chloride over next 2 hours

3) 0.9% sodium chloride 1L with potassium chloride over next 2 hours

4) 0.9% sodium chloride 1L with potassium chloride over next 4 hours

5) 0.9% sodium chloride 1L with potassium chloride over next 4 hours

6) 0.9% sodium chloride 1L with potassium chloride over next 6 hours

Question 7

When may a slower fluid infusion be indicated in DKA?

Answer 7

Slower infusion may be indicated in young adults (aged 18-25 years) as they are at greater risk of cerebral oedema.

Question 8

What does addition of potassium chloride in fluids in DKA management depend on?

Answer 8

Potassium level

Question 9

Potassium guidelines in DKA:

a) K+ level is >5.5

b) K+ level is 3.5-5.5

c) K+ level is <3.5

Answer 9

a) Nil

b) 40

c) Senior review as additional potassium needs to be given

Question 10

Describe insulin regime in DKA

Answer 10

IV infusion at 0.1unit/kg/hour

Once blood glucose is <14 mmol/l an infusion of 10% dextrose should be started at 125 mls/hr in addition to the 0.9% sodium chloride regime

Question 11

When is 10% dextrose given in DKA management?

Answer 11

Should be added to 0.9% saline regime once blood glucose is <14 mmol/l

Question 12

Describe potassium levels in DKA

Answer 12

Serum potassium is often high on admission despite total body potassium being low.

This often falls quickly following treatment with insulin resulting in hypokalaemia.

Potassium may therefore need to be added to the replacement fluids.

Question 13

Describe effect of insulin on potassium?

Answer 13

Causes intracellular shift of potassium

Question 14

When is cardiac monitoring required in potassium infusion?

Answer 14

If rate of infusion is >20 mmol/hour

Question 15

Define DKA resolution

Answer 15

pH >7.3 and;

blood ketones <0.6 mmol/L and;

bicarb >15 mmol/l

Question 16

When can SC insulin be switched to in DKA?

Answer 16

When the DKA resolution criteria has been met AND the patient is eating and drinking.

Question 17

Pathophysiology of HHS?

Answer 17

Hyperglycaemia results in osmotic diuresis with associated loss of sodium and potassium.

Severe volume depletion results in a significant raised serum osmolarity (typically > than 320 mosmol/kg), resulting in hyperviscosity of blood.

Question 18

Why may patients with HHS not look as dehydrated as they are?

Answer 18

Because hypertonicity leads to preservation of intravascular volume.

Question 19

Clinical features of HHS?

Answer 19

1) General: fatigue, lethargy, nausea and vomiting

2) Neurological: altered level of consciousness, headaches, papilloedema, weakness

3) Haematological: hyperviscosity (may result in myocardial infarctions, stroke and peripheral arterial thrombosis)

4) Cardiovascular: dehydration, hypotension, tachycardia

Question 20

3 criteria for diagnosis of HHS?

Answer 20

1) Hypovolaemia

2) Marked hyperglycaemia (>30 mmol/L) WITHOUT significant ketonaemia or acidosis

3) Significantly raised serum osmolarity (> 320 mosmol/kg)

Question 21

Why is it extremely important to differentiate HHS from DKA?

Answer 21

Mx is different –> HHS management does NOT involve insulin.

Question 22

Dehydration & metabolic disturbances in DKA vs HHS?

Answer 22

DKA presents within hours of onset, HHS comes on over many days, and consequently the dehydration and metabolic disturbances are more extreme.

Question 23

Management of HHS?

Answer 23

1) Normalise the osmolality (gradually)
2) Replace fluid and electrolyte losses
3) Normalise blood glucose (gradually)

Question 24

1st line management of HHS?

Answer 24

IV 0.9% sodium chloride

Question 25

If the serum osmolarity is not declining despite positive balance with 0.9% sodium chloride in HHS, what is next step?

Answer 25

The fluid should be switched to 0.45% sodium chloride solution which is more hypotonic relative to the HHS patients serum osmolarity.

Question 26

What is the aimed rate of replacement of fluid loss in HHS?

The aim of treatment in HHS should be to replace approximate

Answer 26

The aim of treatment in HHS should be to replace approximate 50% of estimated fluid loss within the first 12 hours and the remainder in the following 12 hours.

Question 27

Management of hyperglycaemia in HHS?

Answer 27

Fluid replacement alone with 0.9% sodium chloride solution will result in a gradual decline of blood glucose and osmolarity.