Management of Pediatric DKA

Question 1

Diabetic ketoacidosis (DKA) can occur in any patient with an absolute or relative insulin deficiency. DKA is defined by the presence of hyperglycemia, ketosis, and acidosis as measured by serum pH or bicarbonate. Outline the lab value cut offs for what is considered “hyperglycemia”, “ketosis”, and “acidosis”. Note: you do not need to distinguish between severity levels of DKA for this question.

Answer 1

Question 2

Risk factors for DKA include younger age, lower socio-economic status, and delayed diagnosis in new patients. For children and youth with known diabetes, what are some additional risk factors for DKA? Name at least 5 of the 10 listed by the CPS.

Answer 2

i) Previous DKA
ii) Poor glycemic control
iii) Unrecognized insulin pump malfunction
iv) Infection
v) Some medications (e.g., long-acting insulin analogues, atypical antipsychotics, glucocorticoids)
vi) Ethnicity
vii) Limited access to care
viii) Coexisting mental health or social and family issues
ix) Peripubertal stage
x) Adolescence

Question 3

In DKA, hyperglycemia leads to urinary losses of both water and electrolytes, resulting in volume depletion and metabolic disturbances. Low insulin levels reduce glucose utilization, and subsequent cellular glycopenia triggers increased glucagon release, lipolysis, and oxidation of free fatty acids, with ensuing ketoacidosis. How does the serum potassium level compare to total body potassium in patients with DKA?

Answer 3

Serum potassium may be normal or elevated due to extracellular shifts, but total body potassium is invariably low due to osmotic diuresis and active urinary excretion.

Question 4

DKA should be differentiated from hyperosmolar hyperglycemic state (HHS). What are some key distinguishing features between DKA and HHS?

Answer 4

HHS is characterized by more severe volume depletion and extreme electrolyte imbalances in the absence of significant ketosis and acidosis.

Question 5

What are some presenting symptoms of DKA? Note: the initial clinical assessment should include ABCDs and evaluation of tachypnea and altered breathing patterns, perfusion, fluid balance, and level of consciousness. Further evaluation should solicit history of precipitating factors (e.g., infection, intoxication) and medication adherence for individuals with known diabetes.

Answer 5

Polyuria, polydipsia, polyphagia, weakness, nausea, vomiting, abdominal pain, decreased level of consciousness, Kussmaul breathing, and/or acetone breath.

Question 6

Assessing volume depletion can be difficult, with substantial inter-rater variability. For fluid calculations, it is suggested to use what % values to define volume depletion in cases of mild vs severe DKA?

Answer 6

Mild = a minimum of 5% depletion
More severe DKA = 7-10% depletion

Question 7

Laboratory evaluation in patients with DKA should include plasma glucose, electrolytes (including calcium, magnesium, and phosphate), urea, creatinine, anion gap, blood gas, osmolality, and serum/urine ketones to determine the severity of DKA. Outline the pH and bicarbonate cut off values for mild vs moderate vs severe DKA severity. Note: The need for additional studies will be based on clinical circumstances (e.g., hemoglobin A1c, evaluation for infection, electrocardiogram if serum potassium is elevated).

Answer 7

Question 8

A beta-hydroxybutyrate (BHB) level should be measured, if available, in patients with DKA. Do blood BHB levels correlate better with changes in pH and blood bicarbonate than urine ketones? An improved BHB level may indicate that persistent acidosis is due to hyperchloremia.

Answer 8

Yes – urine ketones can be falsely negative.

Question 9

Cerebral injury (CI) occurs more commonly in children than adults. What are some RF’s for CI in patients with DKA? Name at list 5 of the 10 listed by the CPS. Note: the frequency of clinically significant CI may be as high as 1%, and those individuals experience a morbidity between 21-25% and a mortality between 21-24%.

Answer 9

Question 10

Clinical CI is more frequent in severe DKA and may be present before treatment is initiated. What are some clinical indicators aka “warning signs” of possible cerebral injury? Name at least 4 of the 9 listed by the CPS.

Answer 10

Question 11

True or False: Although patients with DKA present with volume depletion, intravenous (IV) fluids have traditionally been restricted in paediatric patients out of concerns for potentiating CI. As an alternative to the traditional osmotic hypothesis of CI, cerebral hypoperfusion and reperfusion likely play a significant role in DKA-related CI. Several levels of evidence, including computed tomography (CT), magnetic resonance imaging (MRI), and cerebral blood flow studies, have shown changes in biochemical markers and progression from cytotoxic to vasogenic edema?

Answer 11

True

Question 12

Treatment of DKA includes progressive volume expansion and a careful reduction in plasma glucose. The diagnosis of DKA should be confirmed before initiating any interventions. It is important to remember that DKA in children is managed differently than in adults. What are some differences/general principles to consider in paediatric patients specifically?

Answer 12

i) Extra caution when administering IV fluids
ii) Initiating insulin only after IV fluids
iii) Replacing potassium earlier and more aggressively
iv) Avoiding insulin boluses and sodium bicarbonate

Question 13

What are some general goals for management of patients in DKA? Note: all patients with DKA require careful monitoring and attention to fluid administration, particularly children and youth at higher risk for CI. In paediatric patients without clinical symptoms of CI, no harm has been demonstrated with using more liberal initial fluid resuscitation, with the primary goal of improving tissue perfusion.

Answer 13

i) Correct volume depletion
ii) Correct acidosis
iii) Stop ketogenesis
iv) Correct electrolyte imbalances
v) Restore normal blood glucose
vi) Monitor for and prevent complications (CI, hypoglycemia, symptomatic electrolyte deficiencies, hyperchloremic acidosis)
vii) Manage coexistent illness or precipitating factors

Question 14

Both saline and balanced crystalloids are appropriate for use as IV fluids in DKA. Balanced crystalloids (e.g., Ringer’s lactate, Plasmalyte) are recognized as safe alternatives to saline for both bolus and ongoing infusions. What are some possible benefits of using balanced crystalloids over saline? Note: while ongoing therapy with 0.45% NaCl with dextrose and added potassium can be safe for most patients with DKA and anormal neurologic status, hypotonic fluids should be avoided in all patients with symptoms of CI.

Answer 14

Balanced crystalloids may minimize hyperchloremic metabolic acidosis, as well as potentially reduce CI and renal injury.

Question 15

As per the specific fluid recommendations for DKA outlined by the CPS, all DKA patients should receive what minimum fluid bolus, regardless of hemodynamic status? Note: in settings of hypotension or compensated shock, give a fluid bolus within 10-15 minutes and administer additional isotonic fluid rapidly, in 10mL/kg increments to a maximum 40 mL/kg, in consultation with a paediatric intensivist.

Answer 15

10-20mL/kg (to a maximum 1000mL) of isotonic fluid (0.9% NaCl or a balanced crystalloid) over 20-30 minutes.

Question 16

After initial isotonic fluid bolus(es) are given to patients in DKA, calculate a starting hourly fluid rate to incorporate both maintenance and deficit fluids, based on replacing an assumed 10% deficit over 36h. What estimated fluid rate is generally safe to give until a detailed fluid calculation is completed? Note: changes in the hourly rate may be considered for patients with less severe volume depletion, and many can transition safely from IV to oral rehydration when ketoacidosis has resolved.

Answer 16

Administering 2x the usual rate of maintenance fluids.

Question 17

As per the CPS, what are the hourly fluid rates that should be used in patients in DKA based on their weight range? Note: these values have been adopted from the updated TREKK guidelines.

Answer 17

Question 18

When giving fluids to DKA patients, dextrose-free isotonic fluids should be continued with a goal of decreasing blood glucose by no more than how many units per hour until the glucose level is between 15-17 mmol/L? Note: at this point, dextrose (usually 5%) should be added and adjusted to maintain a blood glucose of 7-11 mmol/L. This range of blood glucose helps minimize glucosuria, which occurs when the glucose level exceeds 12 mmol/L.

Answer 18

No more than 5mmol/L/h.

Question 19

A two-bag protocol, with each bag containing the same amount of electrolytes but only one containing dextrose, can be used to quickly adjust administered dextrose concentration with finesse (and some cost saving) in response to blood glucose. The 2nd bag should (ideally) contain what % of dextrose to maximize peripheral venous delivery if needed? Outline how the 2-bag protocol should be employed. Note: a two-bag system allows tighter glycemic control and less glucosuria.

Answer 19

12.5% dextrose (but 10% dextrose may also be used).

Question 20

According to the CPS, what are the 2 criteria required for when patients in DKA should start to receive insulin (and never as an IV bolus)? Note: an infusion of rapid-acting insulin at 0.05-0.1 unit/kg/h is preferred, without a weight-based maximum. However, intermittent subcutaneous insulin can be used if IV administration is not possible or in some cases of mild DKA, with the support of expert consultation.

Answer 20

i) Only after the first hour of fluid therapy
AND
ii) When potassium levels are >3.0 mmol/L. Replace potassium before starting insulin if potassium levels are less than or equal to 3.0 mmol/L.

Question 21

In patients with DKA, if blood glucose has been decreasing at a rate >5 mmol/L/h AND administration of IV dextrose has been maximized, to what extent should the insulin infusion be reduced?

Answer 21

Reduce insulin infusion to 0.05 unit/kg/h. A further gradual decrease to no less than 0.025 unit/kg/h can be considered if blood glucose continues to fall rapidly, or as a bridge until the next mealtime (and associated subcutaneous insulin dose) if acidosis has corrected.

Question 22

Patients with DKA present with a relative or total body deficiency of sodium, potassium, phosphate, and magnesium. Hyperglycemia results in factitious hyponatremia (i.e., pseudohyponatremia) but measured Na can be used to calculate the initial anion gap. Assessment and decision-making should be based on the corrected serum sodium. What is the equation for calculating the corrected sodium in these cases?

Answer 22

Corrected sodium = measured sodium + ({glucose – 5} x 0.3))

Question 23

In patients with DKA, an elevated corrected sodium indicates more severe volume depletion. Corrected sodium levels should be carefully monitored because a decrease (or increase) of more than how many mmol/L/h may indicate excessive (or inadequate) fluid resuscitation, with increased risk for CI or acute kidney injury?

Answer 23

More than 2-3mmol/L/h.

Question 24

DKA treatment lowers serum potassium levels, and supplemental potassium of at least 40mmol/L should be added to IV fluids when measured potassium falls below what cut off (and after recent urine output is documented)?

Answer 24

<5mmol/L

Question 25

Serum phosphate may be normal or high despite a total body deficit. Insulin therapy will lower serum phosphate. Consider replacement if measured phosphate is below cut off value? Note: phosphate replacement should also be considered if there are concerns of cardiac dysfunction, respiratory failure, gastrointestinal dysmotility, or metabolic encephalopathy. Follow local protocols for phosphate administration.

Answer 25

<0.5 mmol/L

Question 26

In patients with DKA, why should sodium bicarbonate not be given as a treatment for metabolic acidosis? Note: adequate treatment with fluids and insulin is sufficient for correction of acidosis, unless indicated as part of active cardiopulmonary resuscitation or symptomatic hyperkalemia.

Answer 26

NaHCO3 increases risk for CI.

Question 27

Based on the CPS statement, when managing patients in DKA, laboratory studies should be repeated with what interval frequency during insulin infusion, with measurement of glucose hourly? Additional monitoring includes neurologic status, volume status, and urine output, with added cardiac monitoring in the setting of severe DKA with potentially dangerous metabolic derangements of potassium or calcium.

Answer 27

Every 2h at a minimum.

Question 28

Frequent reassessment of neurologic status in DKA patients is essential to identify and manage CI. If CI is suspected, do not wait for cranial imaging before initiating therapy. Name at least 4 of the 7 components of CI management outlined by the CPS that should be implemented.

Answer 28

i) Minimizing patient movement and agitation
ii) Raising the head of bed to 30°
iii) Maintaining the patient’s head in the midline position
iv) Administering isotonic fluids (change to isotonic if using 0.45% NaCl)
v) Reducing rate of IV fluids to 75% of calculated hourly rate if sufficient to maintain adequate perfusion
vi) Osmolar therapy, either 3% saline delivered at 5 mL/kg over 10-15 minutes (to a maximum 250mL) or mannitol 0.5-1 g/kg (to a max 100g) over 15-20 minutes
vii) Urgent consultation with critical care

Question 29

Intubation is best avoided in patients with DKA. Should a patient’s baseline hyperventilation be maintained if there is a drop in respiratory drive and level of consciousness? Note: consultation with a paediatric intensivist is advised before intubation.

Answer 29

YES – hyperventilation must be maintained.

Question 30

While some mild DKA can be corrected in an emergency department setting, most paediatric patients with DKA should be admitted for ongoing monitoring and management supported by expert consultation. Any abnormal mental status in a child or youth with DKA should prompt urgent referral to the nearest tertiary care centre. What are the 3 general scenarios in DKA cases that should prompt consideration for consultation with critical care/a paediatric intensivist?

Answer 30

i) Children with signs or symptoms of CI
ii) More severe DKA with a pH <7.0 or bicarbonate <5 mmol/L
iii) Less severe cases in children under 5 years of age (especially when presenting outside of a tertiary care centre)