Diabetic Emergencies

Question 1

What is diabetic ketoacidosis (DKA)?

Answer 1

Disordered metabolic state that usually occurs in the context of an absolute or relative insulin deficiency accompanied by an increase in counter regulatory hormones

Question 2

Who gets DKA?

Answer 2

Can occur in both type 1 and 2 diabetics, but more common in type 1

Question 3

What causes ketoacidosis?

Answer 3

Increased lipolysis causes increased FFA to the liver, increases ketogenesis which causes acidosis
Glycosuria leads to electrolyte loss and dehydration, causing increased lactate and acidosis

Question 4

What is needed for biochemical diagnosis of DKA?

Answer 4

Ketonaemia > 3mmol/L or significant ketonuria (>2++ on standard urine stick)
Blood glucose > 11.1 mol/L or known DM
Bicarbonate < 15 morning/L or venous pH < 7.3

Question 5

What is the mortality rate in DKA?

Answer 5

2-5% in developed countries

6-24% in developing countries

Question 6

What causes death from DKA?

Answer 6

Adults = hypokalaemia, aspiration pneumonia, ARDS, co morbidities 
Children = cerebral oedema

Question 7

What are some precipitants to DKA?

Answer 7

Newly diagnosed, infection, illicit drug and alcohol use, non-adherence to insulin/poor self management (most common cause)

Question 8

What are osmotic symptoms of DKA?

Answer 8

Thirst and polyuria

Question 9

What are ketone body related symptoms of DKA?

Answer 9

Flushing, vomiting, abdominal pain and tenderness, breathless (Kussmaul’s respiration), smell of ketones on breath

Question 10

What are some conditions associated with DKA?

Answer 10

Underlying sepsis, gastroenteritis, coma (rare), thrombo-embolism

Question 11

What are the typical biochemistry results at diagnosis of DKA?

Answer 11

Glucose = median level 40 mmol/L, from 11- >100
Potassium = often raises above 5.5 mmol/L
Creating often raised, sodium low, raised lactate, amylase raised, median white cell count is 25
Ketones > 5, bicarbonate < 10 in severe cases

Question 12

What can be lost in DKA?

Answer 12

Fluid = up to 12L
Sodium = 500 mmol
Potassium = 350-700 mmol
Phosphate = 50-100 mmol

Question 13

What are some complications of DKA?

Answer 13

Cardiac arrest secondary to hypokalaemia, ARDS, cerebral oedema, gastric dilation (risk of aspiration)

Question 14

Where are patients with DKA managed?

Answer 14

In HDU

Question 15

How are fluids managed in patients with DKA?

Answer 15

Initially with 0.9% NaCl, once glucose falls to 15 switch to dextrose

Question 16

What are some other management requirements for patients with DKA?

Answer 16

Replace insulin and potassium (rarely phosphate and bicarbonate), possible nasogastric tube, monitor potassium, prescribe prophylactic LMWH

Question 17

How are blood ketones measured?

Answer 17

Using optium meter = measures beta hydroxybutyrate, meter range is 0-8mmol/L, <0.6 mmol/L is normal

Question 18

How are urine ketones measured?

Answer 18

Measure acetoacetate, indicates levels of ketones 2-4hrs previously

Question 19

Does ketonuria resolve straight away in DKA?

Answer 19

No = persists after clinical improvement

Question 20

How can recurrence of DKA be prevented?

Answer 20

Provide patient with ketone meter, arrange DSN follow up and inform GP

Question 21

How is hyperglycaemic hyperosmolar syndrome (HHS) diagnosed by biochemistry l?

Answer 21

Hypovolaemia, hyperglycaemia > 30mmol/L, no/mild ketonaemia < 3mmol/L, bicarbonate > 15mmol/L, venous pH >7.3, osmolarity >320mosmol/kg

Question 22

What can HHS overlap with to cause a mixed clinical picture?

Answer 22

DKA

Question 23

What is the typical presentation of HHS?

Answer 23

Diabetes may be known at presentation (often not), older patients or young Afro Caribbean’s, high refined CHO intake pre-presentation

Question 24

What are some complications and associations of HHS?

Answer 24

MI, stroke, sepsis

Associated medication = steroids, thiazide diuretics

Question 25

Wha is the typical biochemistry of HHS?

Answer 25

Higher glucose than DKA = usually above 50mmol/L, significant renal impairment, sodium often raised, less ketogenic/acidotic than DOA, raised osmolarity

Question 26

How is osmolarity calculated l?

Answer 26

2[Na] + urea + glucose

Normal is 275-295

Question 27

How should HHS be treated?

Answer 27

Administer fluids more cautiously (risk of increased overload)
Administer insulin slowly or not at all
Sodium = <0.5mmol/L/hr, may need 0.45% saline

Question 28

Why should HHS patients be screened for comorbidities?

Answer 28

More likely for comorbidities to occur = all patients get LMWH unless contraindicated

Question 29

What are some features of alcoholic/starvation ketoacidosis?

Answer 29

History important, dehydration common and marked, ketonuria >3mmol/L or significant ketonuria (>2+), bicarbonate usually <15mmol/L or venous pH <7.3 in severe cases, glucose usually normal

Question 30

What are some features of in-patient experience of diabetics?

Answer 30

Longer stay, higher in-patient mortality, higher risk of medical error, enhanced foot risk, poorer overall experience

Question 31

What are some reasons that type 1 diabetics are admitted to hospital?

Answer 31

Unable tolerate oral fluids, persistent vomiting, persistent hyperglycaemia, abdominal pain/SOB, persistent positive/increasing levels of ketones

Question 32

What is the target in-patient blood sugar?

Answer 32

6-10mmol/L, range of 4-12mmol/L is acceptable

Question 33

What patients don’t require right control of their blood sugar?

Answer 33

End of life patients, those who may be severely disabled by significant hypoglycaemia

Question 34

What are some features of elective surgical procedures?

Answer 34

Planned, preferably first on list, pre-assessment clinics

Anaesthetic risk = CV, autonomic dysfunction, foot risk, HbA1c at least <70m/m

Question 35

What are some features of emergency surgery?

Answer 35

Increased risk as unplanned, anaesthetic risk in those with micro/macro vascular complications, care with potassium if glucose is high, post operative sepsis and foot care risks

Question 36

Where does lactate originate from?

Answer 36

Red cells, skeletal muscle, brain and renal medulla = end product of anaerobic metabolism of glucose

Question 37

What is required for lactate clearance?

Answer 37

Hepatic uptake and aerobic conversion to pyruvate then glucose

Question 38

What can lactic acidosis be confused with?

Answer 38

Hyperlactaemia

Question 39

What is the normal lactate range?

Answer 39

0.6-1.2mmol/L = generally lowest in fasted state, may rise to 10mmol/L in severe exercise

Question 40

How is the ion gal calculated?

Answer 40

[Na + K] - [HCO3 + Cl]

Normal range is 10-18 mmol/L, useful for determining cause of acidosis

Question 41

What is type A lactic acidosis?

Answer 41

Associated with tissue hypoxaemia = infarcted tissue, cardiogenic/hypovolaemic shock, sepsis, haemorrhage

Question 42

What are some features of type B lactic acidosis?

Answer 42

May occur in liver disease or leukaemic states, associated with diabetes, consider rare inherited metabolic conditions if well and non-diabetic

Question 43

How does type B lactic acidosis occur in diabetics?

Answer 43

10% of DKA associated with lactate > 5mmol/L, associated with metformin in severe illness states or renslnfailure

Question 44

What are the clinical signs of lactic acidosis?

Answer 44

Hyperventilation, mental confusion, stupid or coma if severe

Question 45

What are the lab findings for lactic acidosis?

Answer 45

Reduced bicarbonate, raised anion gap, raised phosphate, absence of ketonaemia, glucose variable (often raised)

Question 46

How is lactic acidosis treated?

Answer 46

Treat underlying condition with fluids and antibiotics l, and withdraw offending medication