Diabetic ketoacidosis

  • Candidate Instructions
  • Actor Instructions
  • Mark Sheet
  • Score

Location: Junior doctor on medical clerking, you have been bleeped by the ward sister

Patient: 20 year old patient has been referred by her GP for a cough has now developed abdominal pain and is tachypneic

– Take a focused history from the patient
– Perform a full ACDE assessment, a nurse will be available to help you with investigations or management that you require
– After 6 minuets you will be asked a series of questions by the examiner

– Answer any questions that the patient may have

Note to actor: Try to restrain yourself from volunteering too much information – you may do so when prompted (that is, by a specific question, not a general one). If a student is on the wrong line of clinical reasoning do not fuel this line of thinking, state no to the question as being ambiguous may prompt further questioning and does not allow the student to be appropriately tested. The aim of the exercise is to take a focused history; short answers are required.

You were admitted into hospital this morning with a cough from your GP, you have not been seen by the doctor yet. Your tummy has started hurting, it’s a 10 out of 10 for pain. You cannot even focus on what the doctor is saying because you are in so much pain. You keep asking for painkillers when the doctor is asking questions.

If specifically asked you are diabetic, you have not had any of your insulin yet because the nurses have said the doctors have no prescribed it yet. The last time you had your insulin was last night and you have been eating throughout the day.

Category Question
Introduction Candidate appropriately introduced themselves with:
Full name
Medical school, year or grade
Clarifies who they are talking to
Asks patient for preferred name

History History
Presence of abdominal pain
Known diabetic
No insulin been given today
Candidate attempts to find possible precipitant (infection, MI, pneumonia)
Current medications – you do not take any tablets
No drug allergies

Airway assessment Airway assessment
Patient talking, airway patent

Breathing assessment Breathing assessment
Oxygen saturation = 98% on room air
Respiratory rate = 26
Position of trachea = central
Chest expansion = equal
Chest sounds = no additional chest sounds

Breathing investigations
Breathing investigations

Requests ABG / VBG
Show image: Correctly interprets ABG as Uncompensated Metabolic Acidosis

Breathing treatment Breathing treatment
Oxygen 15L through non-rebreathing mask

Circulation assessment Circulation assessment
Blood pressure – 95/87
Heart rate – 110
Peripheral and central cap refill – 4 seconds
Heart sounds = I + II + 0

Circulation investigations Circulation investigations
2 large bore IV cannulae
Bloods = FBC, U&E, CRP, Amylase, LFTs

Circulation treatment Circulation treatment
500ml of 0.9% normal saline STAT

Disability assessment Disability assessment
Blood glucose - 22
Temperature – 37.0
GCS / AVPU score – A on AVPU
Pupils equal and reactive to light

DKA DKA diagnosis by correctly requesting
Urinary ketones

DKA DKA management
1L of 0.9 normal saline over 1 hour (when potassium result available start replacement)
50 units of Actrapid in 49.5ml of 0.9% sodium chloride.
Insulin given at a rate of 0.1 units/kg of bodyweight/hour IV

Escalation Escalation
Candidate offers to call / bleep medical registrar

Question What are the precipitants for this patients diabetic ketoacidosis?
Not prescribed insulin

Question What is the main concern when there is a sudden drop in GCS when treating a patient for DKA?
Cerebral oedema

Question What features of DKA warrants an ITU review?
Blood ketones less than 6 mmol/L
HCO3- less than 5
pH less than 7.1
K+ on admission less than 3.5
GCS less than 12
O2 sats less than 92% on RA
Systolic BP less than 90 mmHg