FN: Diabetic Ketoacidosis Flashcards
Ketogenesis
- Decreased insulin leads to increased stresss hormoes and raise dglucagon
- reduced glucose utilisation and increased fat oxidation
- raised free fatty acids and increased ATP and generation of ketone bodies
Dehydration
- Reduced insulin and decreased glucose utilisation and increased gluconeogenesis –> severe hyperglycaemia
- osmotic diuresis leading to dehydration
- Also, raised ketones and vomiting
Acidosis
- Dehydration –> renal perfusion
2. Hyperkalaemia
Precipitants
- Abdo pain + vomiting
- Gradual drowsiness
- Sighing “kussmaul” hyperventiation
- Dehydration
- Ketotic breath
Diagnosis
- Acidosis (raised AG): pH 11mM (or known DM)
3. Ketonaemia >3mM (>2+ on dipstix)
Investigations
- Urine: ketones and glucose, MCS
- Cap glucose and ketones
- VBG: acidosis + raised K
- Bloods: U_E, FBC, glucose, cultures
- CXR: evidence of infection
Subtleties
- Hyponatraemia is the norm
a. Osmolar compensation for hyperglycaemia
b. raised/normal Na indicates severe dehydration - Avoid rapid decrease in insulin once glucose normalised
a. glucose decreases faster than ketones and insulin is necessary to get rid of them. - Amylase is often raised (up to 10x)
- Excretion of ketones –> loss of potential bicarbonate – hyperchloraemic metabolic acidosis after treatment
Complications
- Cerebral oedema: excess fluid administration - commonest cause of mrotality
- Aspiration pneumonia
- Hypokalaemia
- Hypophosphataemia –> resp and skeletal muscle weakness
- Thromboembolism
Management in HDU
Gastric aspiration
Rehydrate
Insulin infusion
Potassium replacement
Management
- Fluids
- Insulin infusion
- Assessment
- Additional measures
- Monitoring
- Resolution
- Transfer to SC insulin
- Pt. Education
Fluids used
2 bags
2nd bag of fluids with potassium replacement
Insulin infusion
Actrarapid 0.u/kg/h IVI (6units if no wt. mas 15u)
Assessment
Hx + full examination
Investigations: capillary, urine, blood,imaging
Additional MEasures
- Urinary catheter (aim:0.5ml/kg/hr)
- HGT if vomiting or reduced GCS
- Thromoprophylaxis with LMWH
- Refer to specialist diabetes team
- Find and treat precipitating factors
Monitoring
- Hrly capillary glucose and ketones
- VBG @ 60min, 2h and then 2hrly
- Plasma electrolytes 4 hrly
Aims of management
reduced ketones by >0.5 M/h or raised HCO3 by >3mM/h
reduced plasma glucose by >3mM/h
Maintain K in normal range
Avoid hypoglycaemia
Resolution
Ketones 7.3 (HCO3 >18mM)
Transfer to sliding scale if not eating
Transfer to SC insulin when eating and drinking
Transfer to SC Insulin
- When biochemically resolved and eating
- Start long-acting insulin the night before
- Give short-acting insulin before breakfast
- Stop IVI 30min after short acting
Pt. Education
- ID predisposing factors and provide action plan
2. Provision of ketone meter with education on use.
