Paediatric Diabetic Ketoacidosis Scary Statistics DKA most common

Paediatric Diabetic Ketoacidosis

Scary Statistics DKA = most common cause of death in children with IDDM. n 25% of children newly diagnosed with DM 1 present in DKA 15% in serious clinical status. n All DKA admissions after diagnosis are avoidable! n Costly direct and indirect. n

Management 1) 1. 2. 3. Emergency management ABC!! Airway ensure it’s patent. If comatose, insert an airway. Recurrent vomiting – NG tube, aspirate, leave to open drainage. Breathing 100% O 2 by face mask. Circulation insert IV cannula and take blood samples. ECG for T waves (hyperkalaemia)

Cont’d If shocked (poor periph pulses, poor cap re-fill with tachycardia and/or hypotension) give 10 ml/kg 0. 9% (normal) saline as a bolus, and repeat as necessary to a max of 30 ml/kg. NB. There is no evidence to support the use of colloids or other volume expanders in preference to crystalloids.

2. Confirm the Diagnosis History n Thirst/Polydidsia n Polyuria n Weight n Nausea/vomiting n Abdominal pain Due to GLYCOSURIA Due to infectious process or metabolic imbalance

Cont’d Physical findings depressed, weak and dehydrated!! n Tachycardia n Hypotension n Dehydration mild, moderate, severe? n Tachypnoea/Kussmaul n Abdo tenderness similar to acute appendicitis!! n Fruity odour on breath n Altered mental function neuro exam and GCS!!! n FULL examination and WEIGH the child!!

Cont’d Biochemical n High blood glucose on finger-prick test. n Glucose and ketones in urine.

Initial Investigations– What should be checked and what they may show! n n n n Blood Glucose Hyperglycaemia (BM > 11 mml/L) p. H Metabolic acidosis (p. H < 7. 3) Blood Ketones Ketonaemia ABGs Hypocapnic (‘blow off’ CO 2) Base Excess Bicarbonate (low) U and Es Sodium and Potassium FBC

Plus other investigations IF INDICATED! CXR n CSF n Throat swab n Blood culture n Urinalysis n NB. DKA may rarely be precipitated by sepsis, and fever is not part of DKA!

Observations n n n n Strict fluid balance. Urine output for every sample; test for ketones. Hourly BP and basic obs. Capillary ketones if available – more sensitive. Hourly capillary blood glucose Twice daily weight (fluid balance). Hourly or more freq neuro obs initially. Report any changes in conscious level, behaviour, ECG or onset of headache.

Management 1: Fluids n Vol of fluid Requirement = Maintenance + Deficit No more than 10% Deficit (litres) = %dehydration x body weight (convert to ml)

n Maintenance requirements Age 0 -2 years hrs 3 -5 6 -9 10 -14 >15 80 ml/kg/24 70 ml/kg/24 hrs 60 ml/kg/24 hrs 50 ml/kg/24 hrs 30 ml/kg/24 hrs

Add calculated maintenance (for 48 hrs) and estimated deficit, subtract the amount already given as resuscitation fluid, and give the total vol evenly over the next 48 hrs, i. e. Hourly = 48 hr maint + deficit – resus fluid rate 48

Example: A 20 kg 6 -yr-old boy who is 10% dehydrated, and who has already had 20 ml/kg saline, will require: n 10% x 20 kg = 2000 mls deficit n Plus 60 ml x 20 kg = 1200 mls maitenence/24 h = 2400 mls over 48 h n Maintenance + deficit = 4400 mls over 48 h n Minus 20 kg x 20 ml = 400 mls resus fluid = 4000 mls over 48 h = 83 mls/hr!! NB. Do not include continuing urinary losses in your calculations.

n ü ü Type of Fluid: Initially use 0. 9% saline. Once blood glucose to 14 -17 mmol/L, add glucose. If this occurs in first 6 hrs discuss with senior. After 6 hrs 0. 45% saline/5% dextrose. § Oral Fluids: ü ü ü None in severe dehydration, impaired consciousness and acidosis. Only offered after substantial clinical improvement and no vomiting. Need for IV infusions to be reduced.

2. Potassium Once resus complete, commence immediately. n Always a massive depletion of total body K+, even if low to start with, because of insulin. n Initially add 20 mmol KCl to every 500 ml bag of fluid (40 mmol/L). n Check U&Es 2 h after resus, then at least 4 hourly. Adjust K+ replacements accordingly. n ECG observe for T wave changes. n

3. Insulin n n Essential to switch off ketogenesis and reverse the acidosis. Continuous low-dose IV infusion. Run at 0. 1 U/kg/hr maintain at this rate. If rate of glucose fall exceeds 5 mmol/L/hr, or falls to ~14 -17 mmol/L, add dextrose (5 -10%) to IV fluids. Once p. H > 7. 3, BM 14 -17, and dextrose-containing fluid commenced, consider insulin rate, but to no less than 0. 5 U/kg/hr.

4. Bicarbonate Virtually never necessary. n Always consult senior before administering. n Only purpose is to improve cardiac contractility in severe shock. n

5. Phosphate Always a depletion. n No evidence in adults or children that replacement has any clinical benefit and phosphate administration may lead to hypocalcaemia. n

Cerebral Oedema Unpredictable. n More freq in younger children with newly diagnosed diabetes. n Mortality ~ 25%. n Unknown cause. n Aim of DKA therapy slow correction of metabolic abnormalities - incidence of cerebral oedema. n

Signs and Symptoms Headache and slowing of HR. n Change in neuro status (restlessness, irritability, increased drowsiness, incontinence) n Specific neuro signs (e. g. cranial nerve palsies) n Rising BP, decreasing O 2 saturation n Abnormal posturing n More dramatic changes convulsions, papilloedema, resp arrest late signs assoc with extremely poor prognosis. n

Management If suspected – inform senior staff immediately n Exclude hypoglycaemia n Give Mannitol 1 g/kg stat (= 5 ml/kg Mannitol 20% over 20 mins) or hypotonic saline (5 -10 mls/kg over 30 mins) ASAP!!! n Restrict IV fluids to 2/3 maintenance and replace deficit over 72 rather than 48 hrs. n PICU. n CT exclude other diagnoses. n Repeat dose of Mannitol after 2 h if no response. n

Other Complications Hypoglycaemia and Hypokalaemia avoid by careful monitoring and adjustment of infusion rates. n Systemic Infections Abx not given routinely unless severe bacterial infection suspected. n Aspiration Pneumonia Avoid by NG tube in vomiting child with impaired consciousness n