DIABETIC KETOACIDOSIS

• Use this guideline only in patients who have metabolic acidosis
• For symptoms and signs, investigations and to check you are using the correct guideline, use Hyperglycaemia: triage guideline

Definition

• Severe uncontrolled diabetes with:
• capillary ketones (≥3 mmol/L)
• metabolic acidosis (pH <7.3, HCO₃ <15 mmol/L)
• usually with hyperglycaemia (blood glucose >12 mmol/L)
• Beware of normoglycaemic DKA

High-risk patients

• Severe DKA with
• capillary ketones >6 mmol/L
• venous HCO₃ <5 mmol/L
• venous pH <7.1
• hypokalaemia <3.5 mmol/L on admission
• GCS <12
• SpO₂ <92% on air
• systolic BP <90 mmHg
• pulse rate >100 or <60/bpm
• Anion gap >16 [anion gap = (Na⁺ + K⁺) – (Cl^- + HCO₃^-)]
• Young patients (18–25 yr)/elderly
• Pregnant patient
• manage in critical care area and involve obstetric team
• Heart/renal failure
• Other/serious co-morbidities

Search for precipitating causes

• Sepsis (signs of shock)
• Recent myocardial infarction
• Pancreatitis
• Other causes

Investigations for causes

• Serum amylase
• MSU
• If symptoms suggest sepsis, blood culture – see blood culture guideline
• ECG
• Chest X-ray

• Treat cause
• Start on prophylactic LMWH unless contraindication
• If patient febrile and septic and no obvious cause can be found, see Sepsis guideline
• If patient hypotensive or comatose, or fails to pass urine within 3 hr of starting IV fluids, introduce urethral catheter to monitor urine volume
• see Urethral catheterisation guideline
• If hypotension persists beyond 6 hr, look again for evidence of sepsis, myocardial infarction or pancreatitis
• discuss further management with medical SpR
• consider transfer to critical care
• If GCS <8, request review by critical care team for endotracheal intubation and insertion of a nasogastric tube in order to aspirate stomach
• If not on critical care, admit patient to endocrinology ward

• Deliver insulin and IV fluid simultaneously
• only via a set incorporating anti-reflux valves through single cannula
• see Administration of IV insulin infusions and fluid infusions guideline
• Do not use ordinary 3-way taps
• Use IVAC pump to control IV fluid infusion rate and to alert when fluid bag needs replacing
• Never give single doses of insulin (e.g. Actrapid)

• Start fluid replacement before commencing insulin and then run concurrently

First hour

• If initial systolic BP <90 mmHg, give 500 mL sodium chloride 0.9% over 15 min
• if BP remains low, give repeat fluid challenge and seek senior/critical care support early
• If initial systolic BP ≥ 90 mmHg, commence sodium chloride 0.9% IV 1 L over 1 hr

At 60 min (then every 2 hours)

• Potassium (K⁺) review
• take Venous Blood Gas (VBG) for K⁺ (and pH)

Choice of fluid

• NEVER add potassium chloride to infusion bags
• Select pre-mixed bags of sodium chloride 0.9% and potassium chloride
• serum K⁺ ≥5.5 mmol/L, give 1L bag of sodium chloride 0.9%
• serum K⁺3.5–5.4 mmol/L, give 1L premixed bag of sodium chloride 0.9% with 40 mmol potassium chloride
• serum K⁺ <3.5 mmol/L, give two 500 mL premixed bags of sodium chloride 0.9% with 40 mmol potassium chloride - seek senior/critical care help
• Do not prescribe any potassium supplement in first litre of fluid
• addition of potassium is likely to be required in second litre of fluid
• If patient is anuric, do not give potassium
• If possible, while potassium is being infused, attach patient to cardiac monitor
• administration rate above 20 mmol/L/hr requires cardiac monitoring
• K Concentrations >40 mmol/L are painful and may cause severe phlebitis
• give via central line
• if central line cannot be inserted, administer via largest suitable peripheral vein using infusion pump

Rate after first 60 min

• Give chosen pre-mixed bags of sodium chloride 0.9% and potassium chloride
• 1 L over 2 hrs; if giving 500 mL bags, first over 1hr, next over following 1 hr; then
• 1 L over 2 hrs; if giving 500 mL bags, first over 1hr, next over following 1 hr; then
• 1 L every 4 hrs; if giving 500 mL bags, first over 2hr, next over following 2 hr; then
• continue as indicated by volume status (consider slower infusion rate in young adults as increased risk of cerebral oedema)

Background subcutaneous Insulin

• Continue previously prescibed long-acting insulin [e.g. glargine (Lantus), detemir (Levemir) or deguldec (Tresiba)]
• advise nurse to administer alongside IV insulin
• If newly diagnosed diabetes, start long-acting basal insulin at 0.25 units/kg body weight once daily
• e.g. in 60kg body weight, give 15 units of basal insulin once daily
• advise nurse to administer alongside IV insulin
• If patient on subcutaneous insulin pump (CSII), discontinue pump
• contact diabetes team or consultant in charge of patient

IV insulin delivery and infusion

• Use BD micro-fine insulin hypodermic syringes to accurately dose and draw insulin
• do not use ordinary syringe
• 50 units soluble insulin (Actrapid or Humulin S) diluted to 50 mL with sodium chloride 0.9% in 50 mL syringe
• Luer-lok through a spiral or long line delivered by syringe driver pump (so each mL equates to 1 unit of insulin)

Rate

• Commence insulin infusion using standard concentration of 50 units soluble insulin/50 mL sodium chloride 0.9%
• Infuse at rate of 0.1 units/kg/hr (e.g. 60 kg– 6 units/hr). Maximum 15 units/hr
• use patient’s actual weight (if not available, ask patient/estimate weight)

• Maintain a strict fluid intake/output chart
• Remember: always assess patient clinically for fluid status and response to treatment
• While potassium is being infused, attach cardiac monitor to patient
• Capillary glucose hourly for 6 hr, then 2-hrly if patient stable
• Capillary ketones hourly until falls to < 0.6 mmol/L
• Lab glucose, U&E, VBG 2 hr and 4 hr; then 2–4 hrly glucose and U&E till stable
• Monitor patient for complications of over-rapid treatment:
• hypoglycaemia
• cerebral oedema (decreased conscious level +/- focal neurological deficit) in absence of hypoglycaemia
• Adult Respiratory Distress Syndrome (ARDS); hypoxia resistant to high FiO₂ – seek critical care opinion
• Do not use flash glucose monitoring (Freestyle Libre, Dexcom G6) to guide treatment
• use in DKA/HHS is not evaluated

• Remember: always assess patient clinically for fluid status and response to treatment
• Assess for resolution (pH >7.3, capillary ketones <0.3 mmol/L)
• do not rely on HCO₃^- at this stage due to hyperchloraemia from large volume sodium chloride 0.9% infusion
• Treat any complications (e.g. fluid overload)
• Identify and treat any precipitating cause

Fluid Replacement

• If blood glucose falls below 14 mmol/L, commence glucose 10% at 125 mL/hr alongside sodium chloride 0.9%
• caution in elderly, CCF, renal failure

Insulin

• If capillary ketones not falling by 0.5 mmol/L/hr, increase infusion rate by 1 unit/hr until this is achieved
• always check insulin infusion pump is working
• if ketone measurement not possible, HCO₃^- to increase by 3 mmol/hr, blood glucose to reduce by 3 mmol/L/hr
• When blood glucose is <14 mmol/L, consider reducing insulin infusion to 0.05 units/kg/hr to avoid hypoglycaemia
• e.g. for 60kg body weight reduce insulin rate to 3 units/hr
• Continue insulin infusion until capillary ketones <0.6 mmol/L, venous pH >7.3 and/or HCO₃^- >18 mmol/L, then convert to SC insulin regimen
• Do not discontinue IV insulin until 30 mins after starting SC insulin regimen

• Once patient biochemically stabilised (pH >7.3, capillary ketones <0.6 mmol/L) and able to eat and drink, convert to SC insulin regimen

Patient can’t eat/drink

• When ketones normal and acidosis resolved, convert to variable rate insulin infusion as in Hyperglycaemia: can’t eat/drink guideline
• Assess fluid requirement clinically and involve diabetes team

SC insulin

• Transition from IV to SC insulin should take place when the next meal-related SC insulin dose is due (e.g. with breakfast or lunch)
• If already on insulin, continue fixed-rate infusion for 30–60 min after SC insulin administration in conjunction with a meal
• If delay in obtaining diabetes team support, the following is guidance for insulin therapy

Previously using SC insulin dose

• Restart usual insulin
• increasing previous dose by 10–20% for first 2–3 days

Insulin naïve patients

• In patient new to insulin, insulin requirements will fall initially as resistance falls
• ensure close supervision during this period
• Caution in patients with low or high BMI as dosing requirement and insulin sensitivity may vary
• Daily insulin requirement is 0.3–0.5 units/kg
• in elderly, renal failure (CKD stage 4 &5), severe hepatic failure or newly diagnosed type 1 diabetes, use 0.3 units/kg
• all other adult patients, use 0.5 units/kg
• e.g. in a 60 kg patient, total starting dose of insulin is either 18 units or 30 units over 24 hr
• Give 50% of the total dose as long-acting analogue (glargine, detemir or degludec) SC before evening meal or before bedtime

Either

• Divide the remaining 50% into 3 equal doses of quick-acting insulin (Novorapid, Humalog or Apidra) SC
• to be given before breakfast, lunch and evening meal

Or

• If twice daily pre-mixed insulin regimen to be used – ²/₃ of total dose can be given before breakfast and ¹/₃ before evening meal

Adjusting SC insulin regimen

• Once patient using SC insulin regimen, adjust doses to achieve target range of 6–11 mmol/L
• if using soluble insulin before breakfast, lunch and dinner, plus isophane at 2200 hr, use Table as guide to insulin adjustment, raising or lowering appropriate insulin by 2–4 units

• if patient usually using insulin analogue (e.g. lispro/aspart +/- glargine/detemir), additional isophane may be needed – discuss with diabetes team

• Encourage early mobilisation
• Continue prophylactic LMWH until day of discharge (unless contraindicated)
• Check diabetes team have made appropriate follow-up arrangements or refer to diabetes team for out-patient review
• If patient new to insulin, prescribe needles for insulin pens, lancets and sharps guard