Diabetic Ketoacidosis (DKA)

Question 1

Define diabetic ketoacidosis.

Answer 1

Diabetic ketoacidosis (DKA) is an acute metabolic complication of diabetes that is potentially fatal and requires prompt medical attention for successful treatment. It is characterised by absolute insulin deficiency and is the most common acute hyperglycaemic complication of type 1 diabetes mellitus.

Question 2

Explain the aetiology/risk factors of diabetic ketoacidosis.

Answer 2

In DKA, there is a reduction in the net effective concentration of circulating insulin along with an elevation of counter-regulatory hormones.
The two most common precipitating events are inadequate insulin therapy and infection. Underlying medical conditions such as MI or stroke that provoke the release of counter-regulatory hormones are also likely to result in DKA in patients with diabetes. Drugs that affect carbohydrate metabolism, such as corticosteroids, thiazides, pentamidine, sympathomimetic agents (e.g. dobutamine and terbutaline), second-generation antipsychotic agents, and immune checkpoint inhibitors may contribute to the development of DKA.

Question 3

Summarise the epidemiology of diabetic ketoacidosis.

Answer 3

In England, the incidence of hospital admissions for DKA among adults with type 2 diabetes increased 4.24% annually between 1998 and 2013; hospitalisations for DKA in adults with type 1 diabetes increased from 1998 to 2007, and remained static until 2013.

Question 4

Recognise the presenting symptoms of diabetic ketoacidosis.

Answer 4

Polyuria
Polyphagia
Polydipsia
Weight loss
Weakness
Nausea or vomiting
Abdominal pain
Sunken eyes

Question 5

Recognise the signs of diabetic ketoacidosis on physical examination.

Answer 5

Dry mucous membranes
Poor skin turgor
Tachycardia
Hypotension
Kussmaul respiration
Acetone breath
Altered mental status

Question 6

Identify appropriate investigations for diabetic ketoacidosis and interpret the results.

Answer 6

BM
HbA1C
FBC
ABG
Capillary or serum ketones
Urinalysis
Serum urea
Serum creatinine
Serum sodium
Serum potassium
Serum chloride
Serum magnesium
Serum calcium
Serum phosphate
Serum creatine phosphokinase
Serum lactate
LFT
Serum amylase
Serum lipase
Serum osmolality

Question 7

Generate a management plan for diabetic ketoacidosis.

Answer 7

The main goals of treatment are:

• Restoration of volume deficits
• Resolution of hyperglycaemia and ketosis/acidosis
• Correction of electrolyte abnormalities (potassium level should be >3.3 mmol/L [>3.3 mEq/L] before initiation of insulin therapy; use of insulin in a patient with hypokalaemia may lead to respiratory paralysis, cardiac arrhythmias, and death)
• Treatment of the precipitating events and prevention of complications

The majority of patients present to the accident and emergency department, where treatment should be initiated. There are several important steps that should be followed in early management:

• Fluid therapy should be started immediately after initial laboratory evaluations.
• Infusion of isotonic solution of 0.9% sodium chloride at a rate of 1 to 1.5 L/hour should be used for the first hour of fluid therapy.

Question 8

Identify the possible complications of diabetic ketoacidosis and its management.

Answer 8

Hypoglycaemia
Hypokalaemia
Arterial or venous thromboembolic events
Non-anion gap hyperchloremic acidosis
Cerebral oedema/brain injury
Acute respiratory distress syndrome (ARDS)

Question 9

Summarise the prognosis for patients with diabetic ketoacidosis.

Answer 9

The mortality rate is 5% in experienced centres. Death is rarely caused by the metabolic complications of hyperglycaemia or ketoacidosis but rather relates to the underlying illness. The prognosis is substantially worsened at the extremes of age and in the presence of coma and hypotension.