Clinical Practice Guidelines

Diabetes Mellitus

  •  This guideline has been adapted for statewide use with the support of the Victorian Paediatric Clinical Network

    see also: 

    Diabetic ketoacidosis (DKA)

    Background:

    Diabetic ketoacidosis (DKA) is the combination of hyperglycemia, metabolic acidosis, and ketonaemia. It may be the first presentation for a child with previously undiagnosed diabetes. It can also be precipitated by illness, or poor compliance with taking insulin.

    All patients presenting with a blood glucose level (BGL) ≥ 11.1mmol/l should have blood ketones tested on a capillary sample using a bedside OptiumTM meter. If this test is positive (>0.6 mmol/l), assess for acidosis to determine further management. Urinalysis can be used for initial assessment if blood ketone testing is not available.

    The biochemical criteria for DKA are:

     1.       Venous pH < 7.3 or bicarbonate <15 mmol/l

     2.       Presence of blood or urinary ketones

    If ketones are negative, or the pH is normal in the presence of ketones, patients can be managed with subcutaneous (s.c.) insulin (see ' new presentation, mildly ill' below).


    Assessment of children and adolescents with DKA

    1. Degree Of Dehydration (often over-estimated)

    • None/Mild ( < 4%): no clinical signs
    • Moderate (4-7%): easily detectable dehydration eg. reduced skin turgor, poor capillary return
    • Severe(>7%): poor perfusion, rapid pulse, reduced blood pressure i.e. shock

    2. Level of consciousness - Glasgow Coma Scale

    3. Investigations

    Venous blood sample (place an i.v. line if possible as this will be needed if DKA is confirmed) for the following:

    • FBE
    • Blood glucose, urea, electrolytes (sodium, potassium, calcium, magnesium, phosphate)
    • Blood ketones (bedside test)
    • Venous blood gas (including bicarbonate)
    • Investigations for precipitating cause: if clinical signs of infection consider septic work up including blood culture
    • For all newly diagnosed patients: Insulin antibodies, GAD antibodies, coeliac screen (total IgA, anti-gliadin Ab, tissue transglutaminase Ab) and thyroid function tests (TSH and FT4

    Urine

    ·         Ketones, culture (if clinical evidence of infection)

    Management of DKA 

    Children and adolescents with DKA should be managed in a unit that has:

    • Experienced nursing staff trained in the monitoring and management of DKA
    • A paediatric endocrinologist, paediatrician or paediatric critical care specialist with training and expertise in the management of DKA. Where such expertise is not available on-site, telephone advice should be sought from the appropriate specialists
    • Access to laboratories for frequent and timely evaluation of biochemical variables

    1. Airway / breathing - see Resuscitation guidelines

    2. Supportive measures to considerif appropriate

    • Secure the airway and consider ng tube placement (to avoid aspiration) in the unconscious / severely obtunded patient
    • Insert a second peripheral IV catheter for convenient and painless repetitive blood sampling
    • Give oxygen to patients with severe circulatory impairment or shock.
    • Use a cardiac monitor for continuous electrocardiographic monitoring to assess for signs of hyperkalemia (peaked T-waves, widened QRS) or hypokalemia (flattened or inverted T waves, ST depression, wide PR interval).
    • Consider antibiotics for febrile patients after obtaining appropriate cultures
    • Catheterise the bladder if the patient is unconscious or unable to void on demand to allow for strict fluid balance (e.g. in infants and very ill young children).

    3. Fluid Requirements

    Intravenous or oral fluids that may have been given at another facility should be factored into the assessment and calculation of fluid deficit and replacement needs

    Fluid boluses:

    • Not all patients in DKA require fluid boluses. Remember acidosis itself results in poor peripheral perfusion and confounds accurate assessment of dehydration. Peripheral perfusion will improve with correction of the acidosis (with insulin)
    • If hypoperfusion is present, give 0.9% saline at 10 ml/kg and reassess. If centralcapillary refill remains > 2 seconds, a further bolus of 10ml/kg 0.9% saline may be given
    • Patients with DKA rarely require >20 ml/kg in total as a bolus. The potential for harm with over-zealous fluid administration must be remembered. Please discuss the use of additional boluses (> 20ml/kg total) with the endocrinologist on call or local paediatrician

    Initial fluid replacement:

    Commence rehydration with normal saline + potassium (see section 4 below for K+ replacement). The fluid type will need to be adjusted dependent on ongoing glucose, Na and K levels.

    Table shows mls/hour for the initial fluid infusion rate

    Weight
    (kg)

    Mild/Nil

    Moderate

    Severe

     

    Weight
    (kg)

    Mild/Nil

    Moderate

    Severe

    5

    24

    27

    31

     

    38

    100

    125

    155

    7

    33

    38

    43

     

    40

    105

    130

    160

    8

    38

    43

    50

     

    42

    105

    135

    170

    10

    48

    54

    62

     

    44

    110

    135

    175

    12

    53

    60

    70

     

    46

    115

    140

    180

    14

    60

    65

    80

     

    48

    115

    145

    185

    16

    65

    75

    85

     

    50

    120

    150

    190

    18

    70

    80

    95

     

    52

    120

    155

    195

    20

    75

    85

    105

     

    54

    125

    160

    205

    22

    80

    90

    110

     

    56

    125

    160

    210

    24

    80

    95

    115

     

    58

    130

    165

    215

    26

    85

    100

    120

     

    60

    133

    171

    220

    28

    85

    105

    125

     

    62

    136

    175

    226

    30

    90

    110

    135

     

    64

    139

    179

    232

    32

    90

    110

    140

     

    66

    140

    185

    240

    34

    95

    115

    145

     

    68

    145

    185

    245

    36

    100

    120

    150

     

    70

    150

    190

    250

     

    Keep nil by mouth (except ice to suck) until alert and stable.

     Insert a nasogastric tube if the patient is comatose or has recurrent vomiting; leave on free drainage.

    Fluid adjustments 

    Fluid replacement with normal saline and potassium should continue for at least the first 6 hours. If the blood glucose falls very quickly within the first few hours, or if theBGL reaches 12-15mmol/l, change to normal saline with 5% dextrose and potassium.

    Choice of fluid after the initial 6 hours will be influenced by the corrected serum sodium (see below for calculation) and the blood glucose level. Corrected sodium should remain stable or rise as blood glucose level falls. Fluids with a tonicity of < 0.45% saline should not be used.

    Beyond the initial 6 hours, 0.45% NaCl with 5% dextrose and potassium may be used once the BGL is <12-15mmol/l. However, if hyponatremia is present, if the corrected serum sodium fails to stabilise or rise as the BGL decreases, or if hyperosmolar and concerned about rapid shifts in osmolality, 0.9% saline + dextrose and potassium should be continued. 

    Aim to keep the blood glucose level between 5 - 12mmol/l.

    If the patient is still acidotic, and the BGL is < 5.5 mmol/l or is falling rapidly within the range of 5.5 to 15 mmol/l increase the dextrose concentration in the fluid to 10% (plus normal saline + potassium). . The insulin infusion rate should only be turned down if BGL continues to fall despite use of 10% dextrose. In such patients, a reduction in the rate of insulin to 0.05U/kg/hr may be used, provided that metabolic acidosis continues to improve. In this circumstance this should be discussed with a paediatric endocrinologist.

    If the patient becomes hypoglycaemic, manage as per hypoglycaemia section below.

    Rehydration may be completed orally after the first 24 - 36 hours if the patient is metabolically stable (this usually coincides with insulin therapy being switched to s.c. injections). 

    4. Potassium

    Potassium replacement therapy is required for treatment of DKA. This is because a total body deficit of potassium occurs in DKA and correction of the acidosis in the absence of potassium therapy will usually rapidly result in hypokalaemia. Patients may have hyperkalaemia, hypokalaemia or normokalaemia at presentation, depending on the total body potassium deficit and the degree of acidosis. 

    • Defer initial potassium replacement if the serum level is > 5.5 mmol/l or if the patient is anuric (until K+ is < 5.5 mmol/l or urine output documented respectively)
    • Start KCl at a concentration of 40 mmol/l if body weight < 30kg, or 40-60 mmol/l if > 30 kg
    • Subsequent replacement is based on serum potassium levels
    • Potassium replacement should continue throughout i.v. fluid and insulin therapy
    • Once insulin is commenced, a repeat K+ should be taken within one hour

    5. Insulin

    • Add 50 units of clear/rapid-acting insulin (Actrapid HM or Humulin R) to 49.5 ml 0.9% NaCl (1 unit/ml solution).
    • Start rates:

      • 0.1 units/kg/hr in newly diagnosed children, and those with established diabetes who have glucose levels > 15 mmol/l.
      • 0.05 units/kg/hour for children with established diabetes who have had their usual insulin and whose blood glucose level is < 15 mmol/l. This rate should also be considered in young children and may be appropriate during inter-hospital transfer when biochemical monitoring is more limited (NB a doctor should accompany any patient in DKA requiring insulin infusion during transfer).
    • The insulin infusion may be run as a sideline with the rehydrating fluid via a three-way tap, provided a syringe pump is used. Ensure that the insulin is clearly labelled.
    • Adequate insulin must be continued to clear ketones and correct acidosis. Adjust the concentration of dextrose in the intravenous fluids, aiming to keep blood glucose 5-12 mmol/l.
    • The insulin infusion can be discontinued when the child is alert and metabolically stable (pH > 7.30 and HCO3 > 15). The best time to change to s.c. insulin is just before meal time. The insulin infusion should only be stopped 30 minutes after the first s.c. injection of rapid-acting insulin.

    Note: Beware the rare entity of hyperglycaemic-hyperosmolar non-ketotic coma. If this is a possibility, insulin should ONLY be used after discussion with local paediatric team and/or paediatric endocrinologist.

    6. Ongoing monitoring and management

    • Strict fluid balance
    • Hourly observations (more frequently if clinically indicated): pulse, BP, respiratory rate, level of consciousness (GCS), and neurological status (pupillary responses, assess for change eg restlessness, irritability, headache)
    • Hourly glucose and blood ketones measurement (using bedside testing on Optium meter) while on insulin infusion
    • Re-check K+ within one hour of commencing insulin infusion
    • Venous blood gas and lab glucose 2 hourly for initial 6 hours; then 2 - 4 hourly thereafter.  More frequent (hourly) measurements may be necessary in those with severe acidosis / as clinically indicated 
    • Serum urea and electrolytes should be monitored 2 - 4 hourly for the initial 12 - 24 hours (and as clinically indicated thereafter)   
    • 2 - 4 hrly temperature.
    • Nurse head up

    7. Bicarbonate

    Bicarbonate administration is not routinely recommended as it may cause paradoxical CNS acidosis. Continuing acidosis indicates insufficient fluid and insulin replacement. Nonetheless, in rare circumstances, some extremely sick children may benefit from cautious administration (e.g. those with pH < 7.0 +/- HCO3 < 5mmol/L who require adrenaline for BP support or those with marked hyperkalemia). In these children, small amounts may be given after discussion with the consultant endocrinologist.

    HCO3 dose (mmol) = 0.15 x body weight (kg) x base deficit. Give over 30-60 min with cardiac monitoring. Reassess acid base status. Remember risk of hypokalemia.

    Haz ards

    1. Hyper / Hyponatraemia 

    Measured serum sodium is depressed by the dilutional effect of the hyperglycaemia. To "correct" sodium concentration, use the following formula:

    Corrected (i.e. actual) Na = measured Na + 0.3 (glucose - 5.5) mmol/l

    i.e. 3 mmol/l of sodium to be added for every 10 mmol/l of glucose above 5.5 mmol/l.

    If Na is > 160 mmol/l, discuss with senior doctor.

    If sodium does not rise as the glucose falls during treatment or if hyponatraemia develops, it usually indicates overzealous volume correction and insufficient electrolyte replacement. This may place the patient at risk of cerebral oedema. 

    2. Hypoglycaemia

    If blood glucose falls below 4.0 mol/l and patient is still acidotic, give i.v. 10% dextrose 2-5 ml/kg as a bolus and use a 10% dextrose concentration for ongoing iv fluids (with 0.45% NaCl and K+ supplements). Do not discontinue the insulin infusion.

    If hypoglycaemia occurred despite use of 10% dextrose in the preceding 2 or more hours, the rate of the insulin infusion may be decreased to 0.05U/kg/hr as long as ketosis and acidosis are clearing. Continue with a 10% dextrose concentration in i.v. fluids until BGL stable.

    If blood glucose falls below 4.0mmol/l and most recent pH is >7.30, oral treatment for hypoglycaemia (jelly beans + 1 serve of complex carbohydrate) can be used instead of an i.v. bolus of dextrose 10%.

    3. Cerebral Oedema

    Some degree of subclinical brain swelling is present during most episodes of diabetic ketoacidosis. Clinical cerebral oedema occurs suddenly, usually between 6 and 12 hours after starting therapy (range 2 - 24 hr). Mortality or severe morbidity is very high without early treatment.

    Prevention

    Slow correction of fluid and biochemical abnormalities. Optimally, the rate of fall of blood glucose and serum osmolality should not exceed 5 mmol/l/hr, but in children there is often a quicker initial fall in glucose. Patients should be nursed head up.

    Warning signs

    • Risk factors: first presentation, long history of poor control, young age ( < 5 yr)
    • No sodium rise as glucose falls, hyponatraemia during therapy, initial adjusted hypernatraemia
    • Headache, irritability, lethargy, depressed consciousness, incontinence, thermal instability.
    • Very late signs - bradycardia, increased BP and respiratory impairment.

    Treatment

    Mannitol 20% 0.5 g/kg (range 0.25--1.0 g/kg) i.v. over 20 minutes. Give immediately when the clinical diagnosis is suspected - do not delay for confirmatory brain scan. The dose can repeated if no initial response after 30 mins - 2 hours

    Reduce fluid input by 1/3 in the first instance. Nurse head up

    Transfer immediately to ICU level care.

    When to admit/consult local paediatric team:

    • All cases of DKA (suggest early consultation)
    • All cases where diabetes is newly diagnosed
    • Hyper/hyponatraemia

    When to consider transfer to tertiary centre:

    • dxvo If intensive care monitoring is recommended:
      • Children < 2 years of age
      • Coma
      • Cardiovascular compromise
      • Seizures
      • Severe acidosis (ph <7.0 or bicarbonate <5mmol/l)
      • Signs of cerebral oedema 
    • Children requiring care above the level of comfort of the local hospital.

    For advice and inter-hospital (including ICU level) transfers ring the Sick Child Hotline: (03) 9345 7007

    Information specific to MMC

    Children with DKA should be discussed with the paediatric endocrinologist on call at the earliest opportunity.

    Information Specific to RCHChildren with DKA should be admitted and discussed with the endocrinologist on-call.

    New presentation diabetes, mildly ill

    Assessment

    < 3% dehydration, no acidosis and not vomiting

    Investigations for all children newly diagnosed with diabetes

    • Check blood ketones (bedside test) on all patients presenting with BGL ≥11.1mmol/l.

      • If ketones positive (>0.6), assess for acidosis with a venous blood gas; if pH <7.30, proceed as per the DKA guideline.
      • Ketones may be present without acidosis; if this is the case, continue to monitor ketones with each BGL to ensure they are clearing with insulin therapy (monitor until 2 consecutive levels are <0.6 and again if any BGL is > 15.0mmol/l).
    •  GAD antibodies, insulin antibodies, coeliac screen, thyroid function tests

    Additional tests to consider

    • For children / adolescents who are overweight or have clinical evidence of acanthosis nigricans:     

      • C-peptide and insulin levels (may help to distinguish Type 2 diabetes, although T1DM still more likely in this scenario)
      • lipid profile  
      • LFTs

    Management

    The decision about the individual insulin regimen will be made by the paediatric diabetes team in discussion with the family and child. The regimens outlined below are a guide only and individual clinicians may recommend an alternative approach.

    Initial Treatment

    • 0.25 units/kg of quick-acting insulin s.c. stat.

      • If within 2 hr prior to a meal defer and give meal-time dose only.
      • Halve dose if ≤4 yr old. Dose may be lower if not ketotic.

    Ongoing Treatment

    Standard insulin regimens in newly diagnosed patients may comprise either of the two regimens below:

    1. Twice daily injections of a mixture of short and intermediate-acting insulins:

    Usually commence with total daily dose (TDD) of 1 unit/kg/day but this may need modification (e.g. less in younger child aged <5years).

    This is given as 2/3 of TDD in morning, 1/3 of TDD at night. 2/3 of each dose as intermediate-acting insulin, 1/3 as short-acting insulin.

    Note: In children who will be starting twice daily injections but who present after 2200 hrs, it may be too late to start with a mixture of intermediate and short acting insulins. In this instance, give 0.25 U/kg short-acting insulin, which may need to be repeated after 4-6 hours, with a snack (depending on BGL,,ketones and interval to breakfast).

    2. Multiple daily injections (MDI) of insulin using a long-acting insulin analogue at night and pre-meal injections of rapid-acting insulin analogue

    Also start with TDD of ~1.0 U/kg/day.

    • Give 0.4U/kg as basal insulin (long-acting insulin analogue eg insulin glargine) at ~20,00- 21,00 hrs.
    • Give the remainder as rapid-acting insulin in 3 equal doses before meals (i.e. ~0.2 U/kg before each main meal).
    • If children who will start MDI regimens present during the day, slightly higher pre-meal doses may be necessary (e.g. 0.25 U/kg) until basal insulin is given that evening.

    In general, multiple daily injection regimens offer greater lifestyle flexibility (around mealtimes, sport etc); however the child must be old enough to learn how to administer insulin using a pen device without parental supervision (e.g. at school). This is usually possible with children aged >10 years. Twice daily mixed injections are usually commenced in children <10years.

    When to admit/consult local paediatric team:

    • All new presentations of diabetes. In many places these children need to be admitted for commencement of insulin and diabetic education.

    When to consider transfer to tertiary centre:

    • Children requiring care above the level of comfort of the local hospital.

    For advice and inter-hospital (including ICU level) transfers ring the Sick Child Hotline: (03) 9345 7007

    Information specific to MMC

    Diabetes Ambulatory Care Service (DACS) allows for many newly diagnosed children with diabetes to not require hospitalization. Please see relevant paediatric diabetes protocol on MMC intranet policies and procedures site.

    Information Specific to RCH nullAnGel cream can be used for initial doses of insulin in a newly diagnosed childAmbulatory care program at diagnosis

    Children who are well at diagnosis (not acidotic, well hydrated and tolerating oral intake) may be eligible to have their diabetes education and initial stabilisation as an ambulatory care patient. Additional eligibility criteria include age >3years, English speaking family, living within the HITH catchment area, contactable by telephone and absence of any familial / psychosocial impediment to safe care in the community. Prior to linking into this program, children need to have met with the diabetes team (medical team, social worker and diabetes educator) to be assessed for suitability and also to have an initial education session around blood glucose testing and management of hypoglycemia. Hospital in the Home nurses also need to be available to attend the family home to support injections. These requirements generally mean that children who present after lunchtime will not be discharged to HITH until the following day. Direct access to ambulatory care on day of diagnosis is also not possible for children whose initial presentation is on Friday, Saturday or Sunday.Please let the diabetes team know of any new patients in ED as soon as possible, so that every effort to enrol eligible patients in ambulatory care can be made.

    Hyperglycaemic, ketotic mildly ill patients with established diabetes

    Patients with established T1DM who present with hyperglycaemia and ketosis but normal pH, will need additional s.c. insulin to clear their ketones.

    (i) Patients on intermittent daily injections of insulin (bd or MDI)

    Give 10% of the patient's total daily insulin dose as a sub-cut injection of rapid-acting insulin (this is in addition to usual insulin regimen). Monitor BGL and ketones 1-2 hourly. This dose of rapid-acting insulin can be repeated after 2-4 hours if blood ketones are not <1.0mmol/l.

    (ii) Patients on insulin pump therapy

    Need to assume line failure / blockage has interrupted insulin delivery. Give 20% of the patient's total daily insulin dose as a s.c. injection of rapid-acting insulin (higher dose relative to above patient group is because there is no longer acting insulin 'on board' in pump patients). Once s.c. insulin has been given, ask the patient or family to resite the pump cannula and commence delivery at usual settings. Monitor BGL and ketones 1-2 hourly. For patients on pump therapy, ketones should clear to <0.6mmol/l.

    Notify local paediatric team or paediatric endocrinologist if there are any management issues that you want to discuss. If discharged home, the family should be advised to check BGLs and ketones regularly and to follow up with their diabetes nurse educator the following day.

    Consider transfer when:

    • Children requiring care above the level of comfort of the local hospital.

    Information Specific to RCH

    Diabetic educators and the endocrinology team are available for help with management.