Diabetic Ketoacidosis (DKA) Flashcards
Diabetic Emergency
What is diabetic ketoacidosis (DKA)?
A life-threatening emergency in T1DM, characterised by
(1) hyperglycaemia
(2) ketosis
(3) acidosis due to insulin deficiency
What are the three key metabolic abnormalities in DKA?
1 - Hyperglycaemia
2 - Ketosis
3 - Metabolic acidosis
What are the 5 I’s (major causes) of DKA?
5 I’s
1 - Infection
(e.g., pneumonia, UTI)
2 - Inflammation
(e.g., pancreatitis)
3 - Intoxication
(e.g., alcohol, cocaine, SGLT2 inhibitors)
4 - Infarction
(e.g., MI, stroke)
5 - Iatrogenic
(e.g., steroids, surgery)
Why does ketosis occur in DKA?
Insulin deficiency leads to increased lipolysis, releasing fatty acids that are converted into ketone bodies in the liver
What are the classic symptoms of DKA?
1 - Osmotic symptoms
= Polyuria, polydipsia, dehydration
2 - Ketone-related
= Vomiting, acetone breath, abdominal pain
3 - Respiratory
= Kussmaul’s respiration (deep, rapid breathing)
4 - Cardiovascular
= Tachycardia, hypotension
How is DKA diagnosed?
(1) Ketonaemia ≥3 mmol/L
(or ketonuria ≥2+)
(2) Blood glucose >11 mmol/L
(or known diabetes)
(3) pH <7.3 and/or bicarbonate <15 mmol/L
What causes dehydration in DKA?
Osmotic diuresis due to hyperglycaemia, leading to polyuria and electrolyte loss
Why is potassium initially high in DKA?
Acidosis shifts K+ out of cells, increasing serum potassium, but total body potassium is depleted due to urinary losses
What are the first steps in DKA management?
1 - IV Fluids (0.9% NaCl)
2 - IV Insulin (0.1 units/kg/hr)
3 - Potassium replacement
4 - Monitor ketones & glucose hourly
5 - Identify & treat the cause
When should IV glucose (10%) be added to treatment?
When blood glucose falls below 14 mmol/L to prevent hypoglycaemia while continuing insulin therapy
What is a major complication of rapid fluid resuscitation in children with DKA?
Cerebral oedema, which can cause seizures, coma, or death
Why should IV insulin not be stopped immediately once glucose normalises?
Because ketogenesis may still be active—insulin should continue until acidosis resolves
What prophylaxis should all DKA patients receive?
LMWH (low molecular weight heparin)
How does diabetic ketoacidosis present in children?
DKA presents clinically with acute abdominal pain, vomiting, weakness and confusion.
This might be on a background of polyuria, polydipsia and weight loss.
How does HHS differ from DKA?
(1) Much higher levels of glucose
(2) Hyperosmolality
(3) Lack of ketones
(4) Only occurs in people with type 2 diabetes
What is the rate of infusion for insulin in DKA?
0.1u/kg/h
What are the targets in DKA for reducing blood ketones and glucose, and increasing bicarbonate?
(1) Reduce blood ketones by 0.5 mmol/L/hr
(2) Reduce blood glucose by 3.0 mmol/L/hr
(3) Increase venous bicarbonate by 3.0 mmol/L/hr
Which biochemical markers may indicate that fixed rate insulin should be stopped in patients with diabetic ketoacidosis?
Continue fixed rate insulin until:
Blood ketones <0.3mmol/L AND
pH >7.3 AND
Bicarbonate >18mmol/L
‘fruity’ breath odour indicates what?
DKA
Symptoms of DKA
Nausea and vomiting
Abdominal pain
Polyuria
Polydipsia
Weakness
Signs of DKA
Dry mucous membranes
Hypotension
Tachycardia
Altered mental state
(drowsiness, confusion, coma)
Kussmaul’s breathing
(deep, sighing breathing to compensate for metabolic acidosis by blowing off carbon dioxide)
Fruit-like smelling breath
(due to ketosis)
You are an FY2 in A&E. A 9-year-old girl presents to A&E with abdominal pain and vomiting.
She is confused and complains of feeling weak. Her saturations are 98% on air, heart rate is 140 and blood pressure is 80/53. Her blood glucose is 26 mmol/l (normal <6.1), and an arterial blood gas shows a pH of 7.14 (normal 7.35-7.45) and +++ ketones.
While you wait for your senior to arrive to help, what fluid bolus should you give?
10ml/kg 0.9% NaCl over 30 minutes
A 10-year-old girl collapses at school after complaining of weakness and nausea.
On assessment, she was drowsy, with a respiratory rate of 74, heart rate of 158, blood pressure of 90/57, and temperature 37.2°C. Her blood glucose was 29 mmol/L, pH was 7.29, and pCO2 was 3.1.
After 4 hours of fluid resuscitation and insulin, she becomes more alert but complains of a headache. Four hours later, she becomes drowsy again with a respiratory rate of 45, heart rate 48, and saturations 99% on air.
What is the mechanism of this complication?
Swelling of brain parenchyma
You are a medical student in a busy paediatric A&E department.
The consultant shows you a VBG result from a 14-year-old male child who presented with vomiting.
He explains that there is a metabolic acidosis with a raised anion gap.
What does this child most likely have and explain why you think this?
Diabetic ketoacidosis
= DKA presents with a metabolic acidosis and raised anion gap.
Anion gap >16 indicates severe DKA
A 6-year-old girl with a recent history of weight loss and new bed wetting presents to the Accident and Emergency feeling generally unwell. On examination, clinical signs of dehydration and sweet smelling breath are noted.
Which other findings from the history or examination would also be suggestive of a diagnosis of diabetic ketoacidosis (DKA)?
Abdominal pain and nausea +/- vomiting
A 7-year-old girl with a two-week history of weight loss, polyuria and polydipsia is referred to Accident and Emergency from her GP with a suspected new diagnosis of Type 1 diabetes after a urine dip showed raised glucose (+++) and ketones (+++). She is generally well on arrival but the consultant in charge wishes to assess for diabetic ketoacidosis (DKA).
Which investigation should be performed first to assess for DKA?
capillary pH, bicarbonate, glucose and ketones
An 18-year-old man presents to the emergency department with irritability and dizziness. He has a past medical history of asthma and type 1 diabetes mellitus.
On examination, he is sweaty and clammy and has a GCS of 15. A venous blood sample demonstrates a blood glucose of 3.2 mmol/L (normal 4.0-11.0 mmol/L), with all other parameters within the normal range.
What is the best first management step for this patient? and why?
Sugary drink
= This patient is alert and talking and can swallow a sugary drink safely
A 30-year-old man with type 1 diabetes mellitus presents to the emergency department with vomiting and abdominal pain. His observations are BP 85/60, Saturations 95% on room air, HR 100, RR 18
His blood glucose is 25 mmol/L (normal <6.1 mmol/L) and blood ketones are 8 mmol/L (normal <0.6 mmol/L).
His weight is 70kg.
What is the best next step in the management of this patient?
Bolus 500 mL intravenous 0.9% saline
