DKA

Question 1

The management of diabetic ketoacidosis involves

Answer 1

The management of diabetic ketoacidosis involves the replacement of fluid and electrolytes and the administration of insulin.

Question 2

What are the guidelines

Answer 2

To restore circulating volume if systolic blood pressure is below 90 mmHg (adjusted for age, sex, and medication as appropriate), give 500 mL sodium chloride 0.9% by intravenous infusion over 10–15 minutes; repeat if blood pressure remains below 90 mmHg and seek senior medical advice.

When blood pressure is over 90 mmHg, sodium chloride 0.9% should be given by intravenous infusion at a rate that replaces deficit and provides maintenance.

Include potassium chloride in the fluids unless anuria is suspected; adjust according to plasma-potassium concentration (measure at 60 minutes, 2 hours, and 2 hourly thereafter; measure hourly if outside the normal range).

Start an intravenous insulin infusion: soluble insulin should be diluted (and mixed thoroughly) with sodium chloride 0.9% intravenous infusion to a concentration of 1 unit/mL; infuse at a fixed rate of 0.1 units/kg/hour.

Established subcutaneous therapy with long-acting insulin analogues (insulin detemir or insulin glargine) should be continued during treatment of diabetic ketoacidosis.

Monitor blood-ketone and blood-glucose concentrations hourly and adjust the insulin infusion rate accordingly.

Blood-ketone concentration should fall by at least 0.5 mmol/litre/hour and blood-glucose concentration should fall by at least 3 mmol/litre/hour.

Once blood-glucose concentration falls below 14 mmol/litre, glucose 10% should be given by intravenous infusion (into a large vein through a large-gauge needle) at a rate of 125 mL/hour, in addition to the sodium chloride 0.9% infusion.

Continue insulin infusion until blood-ketone concentration is below 0.3 mmol/litre, blood pH is above 7.3 and the patient is able to eat and drink; ideally give subcutaneous fast-acting insulin and a meal, and stop the insulin infusion 1 hour later.

Question 3

DKA is commonly seen in

Answer 3

This is most commonly seen in type 1 diabetes however in some cases it can be a complication of type 2 diabetes

Question 4

Clinical features

Answer 4

 High blood glucose (usually, although not always present)

 Ketones in blood or urine

Question 5

Symptoms

Answer 5

 Increased frequency of urination
 Increased thirst
 Tiredness/ lethargy
 Blurred vision
 Abdominal pain
 Nausea and vomiting
 Smell of ketones on the breath
 Collapse/ unconsciousness

Question 6

Risk factors

Answer 6

 Can be seen at point of diagnosis
 During concurrent illness
 Missing insulin doses
 During a growth spurt or puberty
 Pregnancy
 Binge drinking
 Using illegal drugs

Question 7

Treatment

Answer 7

 Rehydrate with intravenous fluids
 Replace electrolytes with intravenous electrolytes
 Administer intravenous insulin- via a fixed rate insulin infusion.

Question 8

Intravenous fluids

Answer 8

If patients have a systolic BP less than 90 mmHg a fluid bolus of 500mL sodium chloride 0.9% should be given over 10-15 minutes, this can be repeated if BP remains low.
When the BP is over 90 mmHg sodium chloride 0.9% is given at a rate that replaces deficit and provides maintenance.

Question 9

Intravenous electrolytes

Answer 9

Potassium chloride should be given in the fluids unless the patient is suspected of being anuric. This
should be adjusted according to plasma-potassium concentration.

Question 10

Intravenous insulin

Answer 10

• Soluble insulin (Actrapid®, Humulin S) should be given by intravenous injection.
• It is diluted with sodium chloride 0.9% to give a final concentration of 1 unit/mL.
• Initially infuse at a fixed rate of 0.1 units/kg/hour.
• If patient is on a long acting insulin (insulin Lantus® or Levemir®) this should be continues alongside the intravenous insulin infusion.

Question 11

Monitoring

Answer 11

The patient should have their plasma potassium monitored initially after 60 minutes of commencing
treatment, then at 2 hours after treatment started and then every 2 hours thereafter.
If level is outside of the normal range recheck every hour until back in normal range.
Blood-ketone and blood glucose concentrations need to be checked hourly, the rate of the intravenous insulin infusion can be adjusted accordingly- the ketones should fall by at least 0.5mmol/litre/hour and glucose by at least 3 mmol/litre/hour.

Question 12

Next steps

Answer 12

• When blood glucose concentration is less than 14 mmol/litre the patient should be started on a glucose 10% infusion at a rate of 125 mL/hour. This needs to be given in addition to sodium chloride 0.9% infusion.
• The insulin infusion can be stopped when the blood ketone concentration is less than 0.3 mmol/litre and blood pH is greater than 7.3 as long as the patient can eat and drink normally.
• When stopping the insulin infusion the patient should be given a subcutaneous fast acting insulin and a meal and the infusion stopped one hour later.

Question 13

Pathophysiology

Answer 13

Diabetic ketoacidosis (DKA) is a complex disordered metabolic state characterised by hyperglycaemia, acidosis, and ketonaemia. DKA usually occurs as a
consequence of absolute or relative insulin deficiency
that is accompanied by an increase in counterregulatory hormones (ie, glucagon, cortisol, growth hormone, epinephrine). This type of hormonal imbalance enhances hepatic gluconeogenesis and glycogenolysis resulting in severe hyperglycaemia.
Enhanced lipolysis increases serum free fatty acids that are then metabolised as an alternative energy source in the process of ketogenesis. This results in accumulation of large quantities of ketone bodies and subsequent metabolic acidosis. Ketones include acetone, 3-beta-hydroxybutyrate, and acetoacetate.
The predominant ketone in DKA is 3-betahydroxybutyrate

There are several mechanisms responsible for fluid
depletion in DKA. These include osmotic diuresis due to hyperglycaemia, vomiting commonly associated with DKA, and eventually, inability to take in fluid due to a diminished level of consciousness. Electrolyte shifts and depletion are in part related to the osmotic diuresis. Hyper and hypokalaemia need particular
attention.

Question 14

Potassium should be maintained between

Answer 14

4.0 and 5.0 mmol/L

Question 15

The following groups of patients need specialist input
as soon as possible and special attention needs to be
paid to fluid balance

Answer 15

• Elderly
• Pregnant
• Young people 18 to 25 years of age (see cerebral oedema)
• Heart or kidney failure
• Other serious co-morbidities

Question 16

Serious complications of DKA

Answer 16

• Hypokalaemia and hyperkalaemia
• Hypoglycaemia
• Cerebral oedema
• Pulmonary oedema

Question 17

Serious complications of DKA - Hypokalaemia and hyperkalaemia treatment

Answer 17

• no potassium should be prescribed with the initial fluid resuscitation or if the serum potassium level remains >5.5 mmol/L
• 0.9% sodium chloride solution with potassium 40 mmol/L (ready-mixed) can be prescribed if potassium level is <5.5 mmol/L and patient is passing urine.
• review regimen If the serum potassium level falls < 3.5 mmol/L
• monitor sodium, potassium and bicarbonate levels

Question 18

Serious complications of DKA - Hypoglycaemia treatment

Answer 18

• Once the blood glucose falls to 14 mmol/L IV glucose 10% needs to be given to prevent hypoglycaemia

Question 19

The presence of one or more of the following may
indicate severe DKA and admission to a Level 2/HDU
(High Dependency Unit) environment, insertion of a
central line and immediate senior review should be
considered:

Answer 19

• Blood ketones over 6 mmol/L
• Bicarbonate level below 5 mmol/L
• Venous/arterial pH below 7.1
• Hypokalaemia on admission (under 3.5 mmol/L)
• GCS less than 12 or abnormal AVPU scale
• Oxygen saturation below 92% on air (assuming normal baseline respiratory function)
• Systolic BP below 90 mmHg
• Pulse over 100 or below 60 bpm
• Anion gap above16 [Anion Gap = (Na+ + K+) – (Cl- + HCO3-) ]