Diabetic Ketoacidosis and Hyperglycemic Hyperosmolar State

Comprehensive practice flashcards covering the epidemiology, diagnostic criteria, clinical presentation, acute fluid/insulin/electrolyte management, resolution criteria, transition to subcutaneous insulin, and prevention/sick day guidelines for DKA and HHS.

What is serious, acute, life-threatening hyperglycemic?

Diabetic ketoacidosis

What age is DKA more common in?

18-44

What age is HHS more common in?

45-64

What are precipitating factor of DKA and HHS?

Infection, insulin therapy omission, acute illlness

What is the DKA triad?

Hyperglycemia, increased ketones, metabolic acidosis

What do 10% of DKA patients present with?

Euglycemia

What can cause euglycemia?

reduced food intake, pregnancy, impaired gluconeogenesis

What leads to HHS?

Severe hyperglycemia, hyperosmolarity, dehydration

What is the onset of DKA?

Hours to days

What is the onset of HHS?

Days to weeks

Are patients alert in DKA?

Yes

Are patients alert in HHS?

No

What are signs of DKA?

N/V, abdominal pain

What are signs of HHS?

Presents with other acute illness

What glucose levels is present in DKA?

>200

What is the β-hydroxybutyrate level in mild to moderate DKA?

3-6

What is the β-hydroxybutyrate level in mild to moderate DKA?

>6

What is the pH for mild DKA?

7.25-7.3

What is the pH for moderate DKA?

7-7.25

What is the pH for severe DKA?

< 7

What is the glucose level for HHS?

≥ 600

What is the serum osmolarity for HHS?

>320 mOsm/kg

What is the level of β-hydroxybutyrate for HHS?

< 3

What is the pH for HHS?

≥ 7.3

What is done to correct DKA/HHS?

Dehydration, hyperglycemia, electrolyte imbalances

What is the fluid choice for DKA/HHS?

0.9% NaCl or balanced crystalloid

Which fluid leads to faster DKA resolution?

Balanced crystalloid

When should deficit be corrected with fluids?

Within 24-48 hours

What is the initial fluid rate?

500-1000 mL/hr

What happens when glucose falls <250 mg/dL during fluid replacement?

Add D5W or D10W

What type of insulin is used for mild DKA?

Rapid acting

How much units of insulin is used for mild DKA?

0.1-0.2 units

What type of insulin is used for moderate to severe DKA?

IV infusion

How much units of insulin is used for moderate to severe DKA?

0.1 units

What is the target glucose level after getting insulin for DKA?

150-200

What is the target glucose level after getting insulin for HHS?

200-250

What decreases during insulin therapy?

Potassium

What is the target serum potassium for potassium replacement?

4-5

What happens if potassium is < 3.5?

Delay insulin administration

How often should potassium be monitored after insulin administration?

Every 2 hours

What are electrolytes replacements?

Bicarbonate & phsophate

Which electrolyte replacement is not recommended for DKA/HHS?

Bicarbonate

What can bicarbonate electrolyte placement cause?

Hypokalemia

When can bicarbonate electrolyte replacement be used?

pH < 7

What type of electrolyte replacement is

Which clinical presentation signs are shared between DKA and HHS?

Polyuria, polydipsia, weight loss, and dehydration.

What proportion of hyperglycemic emergencies present as a mixed DKA/HHS state?

Approximately one-third ($\frac{1}{3}$) of hyperglycemic emergencies have a mixed presentation of DKA and HHS.

What is the blood glucose criterion for diagnosing DKA?

Blood glucose $\ge 200\,\text{mg/dL}$ or a prior history of diabetes.

What ketone levels fulfill the ketosis diagnostic criterion for DKA?

Serum $\beta$-hydroxybutyrate of $3 - 6\,\text{mmol/L}$ for mild to moderate DKA, $> 6\,\text{mmol/L}$ for severe DKA, or urine ketone strip testing showing $2+$ or greater.

What are the venous pH, serum bicarbonate, and mental status criteria for mild DKA?

Venous pH $7.25 - 7.30$, serum bicarbonate $15 - 18\,\text{mmol/L}$, and alert mental status.

What are the venous pH, serum bicarbonate, and mental status criteria for moderate DKA?

Venous pH $7.00 - 7.25$, serum bicarbonate $10 - 15\,\text{mmol/L}$, and alert to drowsy mental status.

What are the venous pH, serum bicarbonate, and mental status criteria for severe DKA?

Venous pH $< 7.00$, serum bicarbonate $< 10\,\text{mmol/L}$, and stupor or coma.

What are the diagnostic laboratory criteria for hyperglycemic hyperosmolar state (HHS)?

Blood glucose $\ge 600\,\text{mg/dL}$; effective serum osmolality $> 300\,\text{mOsm/kg}$ or total serum osmolality $> 320\,\text{mOsm/kg}$; $\beta$-hydroxybutyrate $< 3\,\text{mmol/L}$ or urine ketones $< 2+$; venous pH $\ge 7.30$; and serum bicarbonate $\ge 15\,\text{mmol/L}$.

In the patient case of MT (a 24-year-old female with T1DM, skipped insulin, vomiting, glucose $342\,\text{mg/dL}$, venous pH $7.18$, bicarbonate $12\,\text{mEq/L}$, and $\beta$-HB $4.8\,\text{mmol/L}$), what is the diagnosis and severity?

Moderate diabetic ketoacidosis (DKA), based on venous pH $7.18$ (range $7.00 - 7.25$), bicarbonate $12\,\text{mEq/L}$ (range $10 - 15\,\text{mmol/L}$), and $\beta$-hydroxybutyrate $4.8\,\text{mmol/L}$ (range $3 - 6\,\text{mmol/L}$).

What are the four pillars of successful management in DKA and HHS?

Correction of dehydration, correction of hyperglycemia, correction of electrolyte imbalances, and identification and treatment of comorbid precipitating events.

What are the initial intravenous fluid options for DKA/HHS resuscitation, and what advantage do balanced crystalloids provide?

Initial fluids are $0.9\%$ $\text{NaCl}$ or balanced crystalloids (Lactated Ringer's or Plasma-Lyte). Balanced crystalloids lead to faster DKA resolution, shorter hospital stay, and lower risk of hyperchloremic metabolic acidosis.

What are the recommended initial IV fluid infusion rate and total replacement timeline for fluid deficits in DKA/HHS?

The initial rate is $500 - 1{,}000\,\text{mL/h}$ during the first $2 - 4\,\text{hours}$ (or $1.0\,\text{L/h}$ for severe hypovolemia), aiming to correct $50\%$ of the fluid deficit in the first $8 - 12\,\text{hours}$ and the remainder over $24 - 48\,\text{hours}$.

At what glucose threshold should dextrose be added to intravenous fluids in DKA management, and why?

When blood glucose drops below $250\,\text{mg/dL}$, $5\%$ or $10\%$ dextrose is added to prevent hypoglycemia while maintaining the insulin infusion needed to clear ketonemia.

How should IV fluid therapy be adjusted in patients presenting with euglycemic DKA (glucose $< 200\,\text{mg/dL}$ and elevated $\beta$-HB)?

Add $5\%$ or $10\%$ dextrose alongside $0.9\%$ $\text{NaCl}$ or balanced crystalloid immediately at the start of insulin therapy.

What subcutaneous insulin regimen is recommended for mild DKA?

A subcutaneous bolus of $0.1\,\text{units/kg}$ rapid-acting insulin analog, followed by $0.1\,\text{units/kg}$ every $1\,\text{hour}$ or $0.2\,\text{units/kg}$ every $2\,\text{hours}$.

What is the recommended IV insulin dosing for moderate to severe DKA?

A fixed-rate continuous IV infusion of regular short-acting insulin at $0.1\,\text{units/kg/h}$, with an optional initial IV bolus of $0.1\,\text{units/kg}$ if there is a delay in setting up the infusion.

What is the recommended initial IV insulin infusion rate for HHS?

A fixed-rate continuous infusion of short-acting insulin at $0.05\,\text{units/kg/h}$.

How should insulin dosing be adjusted once blood glucose reaches $< 250\,\text{mg/dL}$ during DKA management?

Reduce the IV short-acting insulin infusion rate to $0.05\,\text{units/kg/h}$ (or to $0.05\,\text{units/kg/h}$ or $0.1\,\text{units/kg}$ every $2\,\text{hours}$ subcutaneously for mild DKA).

What are the target blood glucose ranges during insulin therapy prior to resolution for DKA and HHS?

Between $150\,\text{mg/dL}$ and $200\,\text{mg/dL}$ for DKA, and between $200\,\text{mg/dL}$ and $250\,\text{mg/dL}$ for HHS.

Why does serum potassium decrease during the treatment of DKA?

Serum potassium falls due to insulin-mediated cellular uptake, correction of metabolic acidosis, volume expansion from fluid resuscitation, and ongoing urinary losses (kaliuresis).

What action should be taken if serum potassium is $< 3.5\,\text{mmol/L}$ prior to starting insulin in DKA?

Delay insulin administration and administer potassium at a rate of $10 - 20\,\text{mmol/L/h}$ until serum potassium is $> 3.5\,\text{mmol/L}$.

How should potassium be replaced when the serum potassium is between $3.5\,\text{mmol/L}$ and $5.0\,\text{mmol/L}$ during DKA management?

Add $10 - 20\,\text{mmol/L}$ of potassium to each liter of IV replacement fluid to maintain serum potassium between $4\,\text{mmol/L}$ and $5\,\text{mmol/L}$.

What is the appropriate management when serum potassium is $> 5.0\,\text{mmol/L}$ at the initiation of DKA treatment?

Start insulin therapy without potassium supplementation, and recheck serum potassium levels every $2\,\text{hours}$.

Why is routine sodium bicarbonate administration avoided in DKA, and what are its potential risks?

It shows no benefit in clinical outcomes or rate of recovery and carries risks of hypokalemia, decreased tissue oxygen delivery, and cerebral edema.

When may sodium bicarbonate be considered in DKA, and what is the recommended dose?

It may be considered only if arterial or venous pH is $< 7.0$, administered as $100\,\text{mmol}$ sodium bicarbonate in $400\,\text{mL}$ sterile water over $2\,\text{hours}$.

When is phosphate replacement indicated in DKA, and what dose is administered?

Only when severe hypophosphatemia ($< 1.0\,\text{mmol/L}$) is accompanied by muscle weakness, respiratory depression, or cardiac compromise; the dose is $20 - 30\,\text{mmol}$ potassium phosphate added to replacement fluids.

What is the recommended monitoring schedule for glucose, electrolytes, and venous pH during DKA treatment?

Blood glucose should be monitored every $1 - 2\,\text{hours}$, while electrolytes, serum creatinine, $\beta$-hydroxybutyrate, and venous pH should be monitored every $2 - 4\,\text{hours}$ until stable, then every $4\,\text{hours}$ until DKA resolves.

In patient MT (initial potassium $5.2\,\text{mEq/L}$), what is the correct initial potassium intervention?

Withhold potassium supplementation, start IV fluids and insulin infusion, and monitor serum potassium every $2\,\text{hours}$.

In patient MT, when glucose drops to $220\,\text{mg/dL}$ but $\beta$-hydroxybutyrate remains elevated and bicarbonate remains low, what is the next step?

Add dextrose-containing IV fluids ($\text{D5W}$ or $\text{D10W}$) and continue the insulin infusion at a reduced rate to permit resolution of ketonemia while preventing hypoglycemia.

What are the formal resolution criteria for diabetic ketoacidosis (DKA)?

Venous pH $\ge 7.30$ or serum bicarbonate $\ge 18\,\text{mmol/L}$, plasma ketones ($\beta$-hydroxybutyrate) $< 0.6\,\text{mmol/L}$, and blood glucose $< 200\,\text{mg/dL}$.

Which laboratory tests should NOT be used as criteria for DKA resolution?

Anion gap and urine ketone testing should be avoided when evaluating DKA resolution.

What are the criteria for resolution of hyperglycemic hyperosmolar state (HHS)?

Calculated or measured serum osmolality $< 300\,\text{mOsm/kg}$, blood glucose $< 250\,\text{mg/dL}$, urine output $> 0.5\,\text{mL/kg/h}$, and improved cognitive status.

When is it appropriate to transition a patient from IV insulin to subcutaneous maintenance insulin?

After resolution criteria for DKA or HHS are met and the patient is clinically stable and able to eat and drink.

How long must the IV insulin infusion overlap with the initial subcutaneous basal insulin dose during transition?

The IV insulin infusion must continue for an overlap period of $1 - 2\,\text{hours}$ after subcutaneous basal insulin administration to prevent rebound hyperglycemia and recurrent ketoacidosis.

What are the three clinical methods used to estimate subcutaneous total daily dose (TDD) of insulin following DKA resolution?

Weight-based estimates, preadmission insulin regimens, and extrapolation from stable hourly IV insulin requirements (e.g., summation over the prior $6\,\text{hours}$).

What are the weight-based total daily dose (TDD) recommendations when transitioning to subcutaneous insulin?

$0.5 - 0.6\,\text{units/kg/day}$ for standard patients, or a reduced dose of $0.3\,\text{units/kg/day}$ for patients with risk factors for hypoglycemia such as frailty or chronic kidney disease.

What is the readmission rate for DKA within the same calendar year in the United States, and what proportion of those readmissions is due to recurrent DKA?

Approximately $22\%$ of patients admitted with DKA are readmitted within the same calendar year, and $86\%$ of these readmissions are caused by recurrent DKA.

What are key components of DKA discharge planning and prevention?

Ensuring an adequate supply of insulin and diabetes supplies, patient re-education on injection techniques and glucose monitoring, reinforcement of the 'Sick Day Guide', and scheduling follow-up within $2 - 4\,\text{weeks}$.

How frequently should blood glucose and ketones be checked during acute illness according to the Sick Day Guide?

Blood glucose should be checked frequently, and ketones should be tested every $4 - 6\,\text{hours}$ whenever blood glucose is $> 200\,\text{mg/dL}$.

According to the Sick Day Guide, what triggers warrant immediate contact with a physician or emergency department visit?

Vomiting or diarrhea lasting $> 4\,\text{hours}$, moderate to large ketones or fruity breath, fever $> 101^\circ\text{F}$ ($38.3^\circ\text{C}$) for $> 24\,\text{hours}$, blood glucose $> 300\,\text{mg/dL}$ on two consecutive readings despite corrections, signs of dehydration, or confusion regarding medication dosing.

What is the '15/15 rule' for treating hypoglycemia during sick days?

Consume $15\,\text{g}$ of fast-acting carbohydrates and recheck blood glucose after $15\,\text{minutes}$ if blood glucose is $< 70\,\text{mg/dL}$.