Diabetic Ketoacidosis (DKA) / Hyperosmolar Hyperglycemic State (HHS)

History

  • Polyuria, polyphagia, polydipsia

  • Headache, fatigue, decreased LOC

  • Nausea/vomiting

  • Abdominal pain

    • If abdominal pain does not improve as ketoacidosis improves, consider other pathologies for abdominal pain

Physical Examination

  • Dehydration, postural hypotension, tachycardia, tachypnea

  • Resp: Kussmaul respiration, acetone-odoured (fruity) breath

  • Abdo: Diffuse abdominal tenderness

  • Neuro: LOC, pupils

Diagnosis

  • Suspect in hyperglycemia and symptoms

    • DKA

      • Develops over hours

      • Typically, anion gap metabolic acidosis (although vomiting may cause a normal pH and normal bicarb)

        • Arterial/venous pH ≤7.3

        • Serum bicarbonate ≤15 mmol/L

        • Anion gap >12 mmol/L

      • Positive ketones in serum and/or urine (acetoacetate)

        • β-hydroxybutyrate level >1.5 mmol/L has a sensitivity of 98-100% and specificity of 78.6-93.3%

        • Ketosis differential:

          • DKA

          • Alcoholic ketoacidosis

          • Starvation ketoacidosis

          • Isopropyl alcohol ingestion

      • Plasma glucose usually ≥14.0 mmol/L

        • Can be euglycemic DKA (eg. SGLT2, pregnancy, chronic pancreatitis, bariatric surgery), will need immediate dextrose infusion

    • HHS

      • Develops over days

      • Plasma glucose >33

      • pH >7.3, Bicarb >15, no ketones

      • Serum osmolality >320mOsm/kg

  • Trigger:

    • Infection (30%)

    • New diagnosis of diabetes (25%)

    • Insulin non-adherence (20%)

    • Infarction (ACS, CVA, mesenteric ischemia)

    • Alcohol

    • Trauma

    • Medications (eg. glucocorticoids, diuretics, atypical antipsychotics)

    • Abdominal pathology

    • Pregnancy

Investigations

  • Blood gas, including lactate

    • Anion gap = [Na+] – [Cl] – [HCO3], if >10-12mEq/L consider elevated anion gap differential

  • Serum osmolality (HHS)

  • CBC, Chem-10 (Ca, Mg, Phos)

  • LFTs, albumin, CK

  • bhCG

  • Capillary Ketones

  • Serum ketones +/- serum beta-hydroxybutyrate level

  • Urinary ketones (more false negatives and false positives)

  • Consider

    • Lipase (note can be increased by DKA)

    • Infectious work-up

      • UA

      • Blood/urine cultures

      • CXR

    • EKG

      • Troponin (only if EKG suggests ischemia)

    • Serum ketons (β-hydroxybutyrate) if diagnosis unclear

Treatment

  • ABC, vitals

    1. Fluid resuscitation

      • Bolus

        • NS 10mL/kg (or 1L) bolus IV

        • If persistent tachycardia or hypoperfusion, repeat until euvolemic (HR<100)

      • Maintenance

        • See table below for rates in pediatrics

        • In adults, eg. 0.9% NS 250mL/h x 4-6h then 0.45% NS 250mL/h (to avoid hyperchloremic metabolic acidosis

      • Add IV dextrose when serum glucose <14.0 mmol/L (maintain glucose 12-14)

        • eg. D5W 0.5%NS or D5W 0.45%NS

        • If glucose <4, provide 1 amp of D50 and increase dextrose infusion

    2. Avoidance of hypokalemia

      • Add KCl 40 mmol/L when serum K<5.0 mmol/L and patient has urinated (cardiac monitoring needed, caution in renal failure- ensure urine output)

        • Consider oral potassium

        • Magnesium/phosphate replacement as needed

    3. Insulin administration (avoid initially in HHS)

      • Hold insulin if K<3.3

      • If mild-moderate DKA (pH 7.1-7.29, HCO3 5-14.9)

        • After one hour of fluids, Humalog 0.15 Units/kg/dose (or 10 units) q2h

      • If severe (pH<7.1, HCO3<5)

        • After one hour of fluids, Humulin R infusion of 0.1 units/kg/h (0.05 units/kg/h for HHS)

        • If glucose does not fall by 3mmol/L in first hour, check IV access and if normal consider doubling insulin

        • Bolus may increase hypoglycemic events without clinical benefits

        • If hypoglycemia give more glucose, do not stop insulin (to avoid more ketoacidosis)

    4. Avoidance of rapidly falling serum osmolality (risk of cerebral edema)

      • Suspect cerebral edema if sudden headache, altered LOC and lethargy, irritability in young children, Cushing's triad (high BP, low HR, low RR)

        • Manage ABC, raise head of bed 30 degrees, restrict fluid

        • Consider mannitol 0.25-0.5g/kg IV over 30 mins OR hypertonic 3% NS 5-10mL/kg over 30 mins

    5. Search for precipitating cause (infection, drugs, thyrotoxicosis, adherence to medication, new diabetes, MI, stroke)

Monitor

  • Repeat serum glucose q1h

  • Repeat VBG (pH, electrolytes), plasma osmolality (for HHS) q2-4h until stable

    • Anion gap = [Na+] – [Cl] – [HCO3] (may consider adjust for albumin with other more complicated formulas)

  • Monitor for Osmolality

    • Calculating osmolality

      • Measure or calculate osmolality (2 [Na+] + [glucose] + [urea] in mmol/L)

        • Aim for gradual decline, especially in patients under 40 years old (eg. 3 mmmol/kg/hr or 20mOsm/kg/day)

          • If osmolality increase

            • Fluid balance inadequate, increase rate of 0.9%NS

            • Fluid balance adequate, consider switch to 0.45%NS

          • If osmolality decreasing >8mosmol/kg/h, consider reducing IV fluids

Goal

  • Avoid overly aggressive therapy which will cause complications (hypokalemia, cerebral edema)

  • Most patients with DKA (especially those with HHS) probably need admission and observation,

  • DKA:

    • Normalization of the plasma anion gap <12 mEq/L

    • Ketoacidosis resolved

    • Normalization of bicarbonate

    • Glucose controlled <14 mmol/L

  • HHS: Mentally alert, and osmolality <315 mOsmol/kg

  • Patient eating and ideally hungry

    • Received full daily dose of long-acting insulin >2 hours (Consider SC insulin regimen once glucose <11.1)

DKA Management

HHS Management

DKA Algorithm MCH_16Jun2021.pdf