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									                             Acute Medicine Clinical Guidelines



Diabetic Ketoacidosis


Diagnosis

DKA is defined by:
       diabetes (known) or blood glucose > 11 mmol/l
       ketonaemia ≥ 3 mmol/l or ketonuria > ++
       acidosis (pH < 7.3 and/or HCO3 < 15 mmol/l)

When (not) to admit to hospital
Patients with newly diagnosed Type 1 Diabetes with ‘mild’ ketosis (not vomiting) and
hyperglycaemia seldom need hospital admission:
 Refer to Diabetes Team (Diabetes Nurse Specialists ext 4198, bleep 7721 /7881, Mon-Fri 9-5)
 Start sc insulin and push oral fluids.
Admission is essential if the patient is acutely ill (e.g. vomiting, dehydrated), young, or elderly.


Initial assessment and investigations

Airway:          naso-gastric tube may be necessary if vomiting / semi-conscious
Breathing:       monitor oxygen saturations
Circulation:     if SBP < 90mmHg, give 500ml saline iv in 15 mins (can repeat, max 3 times total)

Look for evidence of precipitating cause (infection, silent MI etc)

Baseline tests
 Laboratory blood glucose: must be sent on all patients at outset and when monitoring patients
   with HI on meter (blood glucose meters record capillary blood glucose to maximum 27.8
   mmol/l, higher readings are denoted as ‘HI’ on the meter)
 Urea and electrolytes; CRP and TnT where indicated
 FBC (NB a leucocytosis is common – do not use as marker of infection), clotting
 Venous blood gas (VBG) – avoid arterial gases unless hypoxic (O2 sats <95%)
 Urinalysis: test for ketones, protein, blood, leucocytes and nitrites
 Septic screen: blood cultures, MSU; look for other sites of infection especially feet
 ECG; CXR where clinically indicated




Page 1                                                           Acute Medicine Clinical Guideline 15.6 Apr 2010
Authors: A Ward, M Mallet. Reviewed by H Griffiths, A Robinson                            Review date: Apr 2012
Management


     IV line 1 (via pump)                                  IV line 2 (via pump)


      FLUIDS AND K+                          INSULIN                                GLUCOSE



Treat dehydration with 5 to 6      Use insulin infusion to                Use iv glucose as substrate for
litres 0.9% saline over 24 hrs     suppress ketone production             insulin + avoid hypoglycaemia
(age <20, wt < 60kg, see pg 4)



Shocked (SBP < 90 mmHg):           If the patient normally takes          Monitor capillary glucose hourly
                                   glargine (Lantus) or detemir
500 ml 0.9% saline in 15 min       (Levemir), continue at normal          Aim to reduce by ≥ 3 mmol/l/hr
and repeat up to 3x total.         dose sc and ensure it is given
Get senior review                                                         When glucose ≤ 14 mmol/l,
                                                                          start 10% glucose infusion at
                                                                          100 ml/hr.

Not shocked:                       Start intravenous insulin at           Check venous gas within 2 hrs
1.0 litre 0.9% saline over: 1 hr   6 units /hr (prescribe as
1.0 litre 0.9% NaCl + KCl: 2 hr    Adjusted Regime 1 on Adult iv
1.0 litre 0.9% NaCl + KCl: 3 hr    insulin chart).
1.0 litre 0.9% NaCl + KCl: 4 hr
1.0 litre 0.9% NaCl + KCl: 6 hr    Monitor capillary glucose hourly        Aim to keep glucose 12 - 16
1.0 litre 0.9% NaCl + KCl: 8 hr    (if HI on meter, check lab or           mmol/l (& hence insulin at 6+
                                   blood gas analyser glucose)             units /hr) by adjusting rate of
                                   and venous gas hourly initially         10% glucose infusion
caution in elderly / younger /
pregnant / heart failure
                                                                           continue until bicarb > 18
                                                                           (or pH >7.3 if > 6 hrs from
                                                                           onset of treatment).
                  +                Aim for bicarb to increase by
Monitor plasma K (VBG / lab)       ≥ 3 mmol/l/hr and glucose to
2 – 4 hrly (see p3); add KCl to    fall by ≥ 3 mmol/l/hr
       +
keep K 4.0 – 5.0 mmol/l, eg:
                                                                           If blood glucose rises > 16
 +                                 If not achieved, check pump,            mmol/l, reduce rate of glucose
K > 5.5           none             then increase insulin by 1
  +
K 5.0 – 5.5       20 mmol/l                                                infusion to 75 ml/hr.
  +                                unit/hr every hour to achieve
K 2.5 – 4.9       40 mmol/l        these goals
  +
K < 2.5           60-80 mmol/l                                             If blood glucose < 12 mmol/l,
(central line + ECG monitoring)                                            increase rate of glucose
                 +
Caution with K in renal failure                                            infusion to 125 ml /hr
or if urine o/p < 30 ml/hr
                                   Once bicarb > 18 (or pH >7.3 if
                                   > 6 hrs from onset of
                                   treatment), use Scale B on
                                   Adult iv insulin chart.                 When acidosis resolved ie
Consider using 0.45% sodium                                                bicarb > 18 (or pH >7.3 if > 6
chloride if serum sodium           Restart usual sc regime if              hrs from onset of treatment),
above 155 mmol/l and not           eating and drinking (stop iv            stop iv glucose if eating and
falling (discuss with senior)      insulin 30 minutes after meal)          drinking




Page 2                                                  Acute Medicine Clinical Guideline 15.6 Jan 2010
Management notes

Patients are ill and require intensive monitoring. Get senior review and consider referral to HDU if:
 Bicarb < 5 mmol/l or pH < 7.1 on presentation

   K+ < 3.5 on admission
 GCS < 12 or abnormal AVPU scale
 O2 saturation < 92% on air if normal baseline respiratory function
 SBP < 90 mmHg; HR > 100 or < 60 bpm
                               +    +    -         -
 Anion gap > 16 [AG = Na + K - (Cl + HCO3 )]


All patients should have 2 good cannulae inserted; one for fluid replacement, the other for insulin
and dextrose. Do not use feet in patients with diabetes.

Monitoring
 Blood glucose (at least) hourly
      +   +
 Na , K and venous pH + bicarb at 1, 2, 4, 6, 8, 12, 16 hrs
              2+
 U+E and Mg at 8 and 24 hrs


Investigations:
  Hyperamylasaemia without pancreatitis is not uncommon
  Magnesium / phosphate usually fall with treatment: replace Mg if < 0.6 mmol/l. Replacing PO4
   not generally recommended as doesn’t affect outcome acutely and can cause hypocalcaemia.

Sodium Bicarbonate
Not indicated. Consider only if pH <6.9 and venous bicarbonate <9 and failing to improve despite
treatment, but must be discussed with ITU or diabetes consultant first. Give 100 mls of 1.26%
sodium bicarbonate; repeat blood gas/bicarbonate 30mins later. Discuss with ITU if no benefit.

Antibiotics
These are not needed as part of routine care. If an infection is the likely precipitant to this episode
of DKA, start antibiotics in accordance with the RUH antibiotic policy.

Monitor urine output
Consider inserting a catheter if no urine at 6 hours. Check for ketones

Elderly
If patient has a cardiovascular history and/or is elderly (>65 yrs old), a CVP line, ECG monitoring
and urinary catheter are mandatory.

VTE prophylaxis
All patients should have prophylactic enoxaparin (40 / 20 mg sc od) unless contraindicated.

Ongoing care
Refer all patients with DKA to the Diabetes Liaison Nurses; transfer to diabetes ward when
clinically stable.



Resolution
   Resume diet as soon as patient is able.
   Once eating, if the pH > 7.3, sc insulin should be resumed if the patient is well. Urinary
    ketones may take longer to clear.
   If the patient is on a basal bolus regimen and has continued their basal insulin (see above),
    give usual rapid acting insulin before next meal and stop IV insulin 30 minutes after the meal.



Page 3                                                   Acute Medicine Clinical Guideline 15.6 Jan 2010
   If patient is on a BD regimen and insulin infusion is to be stopped at lunchtime, give half the
    normal breakfast dose before lunch and stop IV insulin 30mins after lunch. Recommence
    usual BD regimen with evening meal. At breakfast or tea, give usual insulin and disconnect
    pump 30 mins later.
   If patient is newly diagnosed with Type 1 Diabetes and Diabetes Team not available then
    calculate total daily dose as 0.5 units x body weight in kg (use 0.75 units/kg in teens and
    obese). Give half as basal (eg Lantus) in the evening and the rest divided equally as bolus (eg
    NovoRapid) before meals. Alternatively, start patient on Human Mixtard 30 or Novomix 30: 2/3
    calculated dose before breakfast and 1/3 with evening meal.


Younger adults

Adequate IV fluid replacement is vital - most patients are fluid depleted by 5 litres or more.
However if the patient is < 20 yrs and weighs < 60 kg it is particularly important not to replace the
fluids too quickly, to avoid cerebral oedema. Therefore all fluids given must be documented.

Assess degree of dehydration:
 3% dehydration is only just clinically detectable
 mild: 5% - dry mucous membranes, reduced skin turgor
 moderate: 7.5% - above with sunken eyes, poor capillary return
 severe: 10% (+ shock) – very ill, poor perfusion, thready rapid pulse, (hypotension is late sign)


To calculate fluid requirement for first 48 hrs (following treatment for shock):

    Requirement = Maintenance + Deficit
    Deficit (in litres) = % dehydration x body weight (kg); convert this to ml (don’t use more
    than 10% dehydration in the calculations).
    Maintenance requirements = 60 ml / kg / 48 hrs
    Hourly rate = (48 hr maintenance + deficit – resuscitation fluid already given) / 48

    Example :
    A 50 kg 18 year old girl who is 10% dehydrated, and who has already had 500ml saline,
    will require
     10 % x 50 kg = 5000 mls deficit
     plus 60ml x 50kg = 3000 mls maintenance for 48 hours
     hourly rate = 3000 + 5000 - 500 mls resus fluid = 7500 mls over 48 hours = 156 mls/hour


Note
  Use 0.9% saline initially. Monitor Na+ closely: if Na+ stable after 6 – 8 hours consider using
   dextrose / saline.
  Do not include continuing urinary losses in the calculations
  When good clinical improvement occurs before the 48hr rehydration calculations have been
   completed, reduce iv input to take account of oral intake

See BSPED DKA Guideline for further information; discuss with paediatric registrar if in doubt.



Related documents

ADA consensus statement 2006

NHS Diabetes DKA guideline 2010


Page 4                                                  Acute Medicine Clinical Guideline 15.6 Jan 2010

								
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