Diabetic Ketoacidosis in Children: Tygerberg Children's Hospital Protocol

Make the diagnosis

Clinical

Assess severity

Shock

Refer to ICU

Consider ICU admission

Bloods and other tests at admission

Fluid therapy

Mild DKA

Make the diagnosis 

• Hyperglycaemia (BG > 11 mmol/l) 
• Heavy glycosuria (>55mmol/l) 
• Blood BOHB >0,6mmol/l or ketonuria 
• pH < 7.3 
• SB < 15 mmol/l 

Clinical

• Polyuria 
• polypsia 
• ≥5% dehydration 
• ± Kussmaul respiration 
• ±Vomiting 
• ±Abdominal pain 
• ± Drowsy 

Beware: Euglycaemic DKA 
Hyperglycaemic Hyperosmolar-State (HHS): 

• BG > 33,3mmol/L
  
• Ph>7,3
  
• SB > 15mmol/L
  
• Absent / Mild BOHB (1mmol/L), Small Ketonuria
  
• Effective Osmolaility >320 Mmol/L
  
• Stupor / Coma.

Assess Severity 

Shock

Tachycardia, ± hypotension, poor pulse volume, delayed capillary refill time 

Beware: 

Stress response causes tachycardia and hypertension or a SBP in upper normal range. 

Refer to ICU 

1. Requiring ≥40ml/kg of NS to correct shock. 
2. Anuria – persistent or redeveloping after shock was corrected 
3. Depressed LOC not associated with initial shock. 

Consider ICU admission 

1. pH <7,1 
2. Elevated urea 
3. Children under 2 years. 
4. Hyperventilate to blow off CO2 

Calculate: 

Effective Osmolality =2(Na) + BG m0sm/kg (N=280-295) 

Anion gap = Na-(Cl+HCO₃) (N=8-16) 

Bloods and other tests at admission

1. Weight: If unknown, measure length & estimate weight from height chart 
2. Laboratory glucose 
3. pH, pCO2, SB, base deficit (venous blood gas is acceptable) 
4. Na, K, CI, U, Cr, (Ca, Mg, Pi and Alb) 
5. Infection screen if indicated (but no acute phase reactants during DKA) 

FLUID THERAPY 

1. Resuscitation 
   • Treat shock first
     
   • Stay with the child until shock is corrected
     
   • Aim: N SBP for age and a significant drop (of at least 10%) in HR. 
     
   • Proceed to step 2-4 when hypovolaemia corrected.
   • Oxygen.
     
   • Start insulin only if shock has been corrected (early use is associated with cerebral oedema)
     
   • Hypotension: NS 0,9% 20ml/kg over 10-30 min 
   • Compensated shock: NS 0,9% 10ml/kg over 10-30 min
     
   • Reassess. Repeat until aim achieved.
     
   • Consider nasogastric tube (vomiting, depressed LOC)
2. Maintenance (over 24hrs) 
   • 0-2 yrs: 80ml/kg/24 hrs
   • 3-5 yrs: 70ml/kg/24 hrs
   • 6-9 yrs: 60ml/kg/24 hrs
   • 10-14 yrs: 50ml/kg/24 hrs
   • >15 yrs: 30ml/kg/24 hrs
3. Rehydration (over 48 hours) 
   • 5% dehydrated: 50ml/kg/48hrs
   • 10% dehydrated: 100ml/kg/48hrs
   • Review at least 6 hourly. 
4. Ongoing losses 
   • Replace urine loss in excess of 2ml/kg/hour = urine output in ml/kg/hr – 2 ml/kg/hr

Aims for Fluids for rehydration, maintenance and ongoing losses: 

1. Effective osmolality at 4 hrs should be the same or up to 4mOsm/kg higher than baseline (an early drop may be associated with cerebral oedema). 
2. Rehydrate over 48 hours 
   • NS (0,9%) for first 4-6 hours 
   • ½ NS (0,45%) after 6 hours (excessive NS has been associated with hyperchloraemic acidosis) unless attenuated rise/drop in serum Na. 
   • ½ NS (0.45%) saline or NS (0,9%) until BG <15 mmol/l. 
   • Add 5% dextrose to NS/½ NS (whatever is applicable) to maintain BG between 8 – 12 mmol/l or if BG drops by >5mmol/l/hr (5%DW/NS = rehydration fluid). Should the BG rise again above 15 mmol/l, you may increase the insulin infusion temporarily by 25% (i.e. increase to 2,5ml/hr – see below) 
   • Change to 10% dextrose if BG <8 mmol/l and ketonaemia persists. 
   • The insulin infusion rate should only be decreased if the BG remains below 8 mmol/l despite glucose supplementation. 

Insulin – soluble (regular) insulin (Actrapid) 

• Infusion – 0.1 units/kg/hour (consider 0.05 units/kg/hour in child under 5years) 
• Aim: BG should drop at a rate not faster than 2-5 mmol/l/hr 

By syringe driver: 

• 0.1units x mass = units/kg/hr 
• Units/kg/hr x 6hours = units/kg/6hours 
• Add units/kg/6hours to 12ml normal saline 
• Prime tubing, Run at 2 ml/hour 

Alternatives for referring doctor 

NB – Insulin should only be started after the resuscitation is complete. If the transfer to TBH is quick, it is not essential to give any insulin at all – please discuss this with the receiving doctor first.

1. 25 units in 100ml normal saline, run at (0.4 x weight in kg) ml/hr, remember to prime tubing. This still requires an infusion pump. 
   
2. 50 units in 500ml normal saline (1 unit / 10ml), infuse at 0.1 units/kg/hour, change bag every 24 hours. 
   
3. Hourly subcut/im insulin 0.1u/kg – this will only work if the patient is not shocked. 
   
4. Never give insulin during a transfer. If the transfer is going to be lengthy, consider a bolus dose of soluble insulin 0.1unit/kg iv prior to transfer. 

Do not decrease or stop the insulin infusion below 0.05 units/kg/hour until the child is clinically well, and blood BOHB <0,6 mmol/l or ketonuria has resolved, but ensure that the child’s BG is maintained between 8-12 mmol/l as described above. 

Potassium 

Start as soon as resuscitation is complete 

• and The child is passing urine 
• The ECG does not show elevated T-waves OR
• serum potassium is  4.5 mmol/l or upper limit for lab 
  •  Give 40mmol KCl/l in iv fluids (40mmol KCl = 20 ml of 15% KCl) 
    • Increase KCI supplementation if necessary – maximum IV rate 0,5mmol/kg/hr 
  •  Give potassium phosphate only if serum phosphate very low and clinically weak. Usually KCl and KPO4 is added in equal volumes to iv fluids for 6-12 hours of therapy ONLY – monitor serum Ca. 

Calculations: 

• 1 ml 15% KCl = 2 mmol K+; 1 gram KCl = 13 mmol K+ 
• 1ml K2PO4 = 2 mmol K+ and 1.4 mmol PO4 

Sodium 

• If the sodium does not increase, or falls, use normal (0,9%) saline. Beware of cerebral oedema. 
• If the initial sodium is >150 mmol/l, use half-normal (0.45%) saline and rehydrate more slowly (>48hrs) 

Hyperglycaemia may cause false hyponatraemia: 

Persistent acidosis results from: 

1. Inadequate resuscitation. 
2. Inadequate insulin. 
3. Sepsis 
4. Excessive NS admin (hyperchloraemic acidosis) 

Sodium bicarbonate therapy 

• Contraindicated: Associated with cerebral oedema 
• Consult paed endocrinologist on call first if possible, otherwise ICU consultant on call. 
• NaBic should not be needed if the patient is not in ICU 
• Do not use NaBic in the initial resuscitation. 
• Correct by 25% over 4 hours (not a bolus) 
• mmol bicarbonate = (base deficit x 0.3 x body weight) ÷ 4 
• Stop when pH  7.15 or standard bicarbonate > 8 mmol/l 

Oral fluids during recovery 

• With severe DKA – oral sips / ice only 
• Start oral fluids only after substantial clinical improvement, and when there is no vomiting. 
• Remember to subtract from iv input. 

Antibiotics – if indicated clinically. Remember usually DKA is precipitated by insulin omission.. 

Manage stomach and bladder – NG drainage and bladder catheterisation as needed. 

Complications 

1. Cerebral oedema – as the patient is improving. Signs: Headache 
   • Change in vital signs: ↓HR, ↑BP, ↓O₂ saturation, fever Change in CNS signs: ↓LOC, irritability, restlessness, incontinence. CNS signs: cranial n palsies, posturing, seizures (convulsions, papilloedema and respiratory arrest occur late and have a very poor prognosis) 
   • Treatment: 
     • Exclude hypoglycaemia 
     • Mannitol 1g/kg iv immediately, over 20 minutes 
     • Halve iv fluid rate 
     • Elevate head 
     • ICU 
     • Mannitol 0.25g/kg/hour as infusion or boluses 4-6hrly 
     • CT head only when stable 
2. Technical – tissued drips, blocked lines, leaks, uncontrolled infusion etc. 
3. Recurrence ketoacidosis – from stopping insulin too early. 
4. Hypoglycaemia 
5. Hypokalaemia or hyperkalaemia 
6. Aspiration pneumonia 

Mild DKA 

• Drink adequate fluids (maintenance + up to 5% rehydration) 
• Give extra Actrapid 0,05u/kg if BG >11 mmol/l and 0,1u/kg if BG ≥15 mmol/l 
• Monitor BG and blood BOHB/urine ketones 2-4 hourly depending on severity. 
• Repeat Actrapid 2-4hrly until ketone free. 

Changing to subcutaneous insulin 

• Plan to switch at a mealtime – breakfast is most convenient! 
• Work out insulin requirements (start at 0.6U/kg/day or less – 2/3 before breakfast, of which 1/3 actrapid, 2/3 protaphane; remaining 1/3 divided into 1/3 and 2/3 or ½ and ½ , actrapid 1/3 0r ½ before supper, protaphane 2/3 or ½ at 21h00) 
• Give first subcutaneous dose of insulin. 
• Meal 30 minutes thereafter. 
• Stop insulin infusion +/- 60 minutes after subcut. Injection. 
• Diabetic diet includes breakfast, snack, lunch, snack, supper, snack! 
• Insulin requirements frequently remain high for a few days and then drop again – consider extra doses of actrapid (0.05 – 0.1U/kg/dose) if blood glucose is > 15 mmol/l (and beware hypoglycaemia!).