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

What is Diabetic Ketoacidosis (DKA)?

A life-threatening complication of diabetes characterized by hyperglycemia, ketosis, and metabolic acidosis.

Which type of diabetes is most associated with DKA?

Type 1 diabetes mellitus.

What is the primary cause of DKA?

Absolute or relative insulin deficiency leading to impaired glucose utilization.

What triggers DKA in diabetics?

Infection, illness, stress, missed insulin doses, or undiagnosed diabetes.

What is the hallmark triad of DKA?

Hyperglycemia, ketosis, and metabolic acidosis.

What happens to blood glucose in DKA?

It rises, usually above 250 mg/dL.

What happens to ketone production in DKA?

Increased breakdown of fat leads to elevated ketone bodies in the blood and urine.

What causes the acidosis in DKA?

Accumulation of ketone acids from fat metabolism.

Why does dehydration occur in DKA?

Osmotic diuresis caused by hyperglycemia leads to fluid and electrolyte losses.

What is the typical pH level in DKA?

Less than 7.3, indicating metabolic acidosis.

What is the typical bicarbonate level in DKA?

Less than 15 mEq/L.

What electrolyte is most often decreased in DKA?

Potassium.

Why is serum potassium low in DKA?

Loss through osmotic diuresis and shifting into cells during insulin therapy.

What are early clinical manifestations of DKA?

Polyuria, polydipsia, weight loss, and fatigue.

What are later clinical manifestations of DKA?

Nausea, vomiting, abdominal pain, and dehydration.

What breathing pattern is characteristic of DKA?

Kussmaul respirations (deep and rapid).

What causes Kussmaul respirations in DKA?

The body's attempt to compensate for metabolic acidosis by exhaling CO₂.

What is the fruity odor in DKA due to?

Acetone, a volatile ketone excreted via respiration.

What mental status changes can occur in DKA?

Confusion, lethargy, or coma.

What does DKA do to serum osmolality?

It increases due to hyperglycemia and dehydration.

What are the diagnostic findings in DKA?

Blood glucose >250 mg/dL, pH

What urinalysis findings are typical in DKA?

Presence of glucose and ketones.

What is the priority in managing DKA?

Restore circulating volume and tissue perfusion.

What IV fluid is used first in DKA?

Normal saline (0.9% NaCl).

When is hypotonic saline (0.45% NaCl) used in DKA?

After initial rehydration if sodium is normal or high.

When should dextrose be added to IV fluids in DKA?

When blood glucose falls to around 200-250 mg/dL.

What type of insulin is used in DKA management?

Regular insulin (IV infusion).

What is the initial insulin bolus for DKA?

0.1 unit/kg IV bolus.

What is the continuous insulin infusion rate for DKA?

0.1 unit/kg/hour IV.

How often should blood glucose be monitored in DKA?

Every hour until stabilized.

What electrolyte must be closely monitored during DKA treatment?

Potassium.

When should potassium replacement begin in DKA?

Once urine output is adequate and serum K⁺

Why is insulin not started immediately if K⁺ is low?

Insulin drives potassium into cells, risking severe hypokalemia.

What is the purpose of correcting acidosis in DKA?

To restore normal enzyme activity and prevent cardiac complications.

When is bicarbonate therapy indicated in DKA?

Only if pH is

What is the expected urine output goal during DKA treatment?

30-60 mL/hour.

What vital sign changes occur in DKA?

Tachycardia, hypotension, and tachypnea.

What indicates improvement in DKA?

pH >7.3, bicarbonate >18, and absence of ketones.

What complications can result from overhydration?

Pulmonary edema or cerebral edema.

Why is cerebral edema a risk in DKA correction?

Rapid decrease in serum osmolality during fluid replacement.

What is Hyperosmolar Hyperglycemic State (HHS)?

A severe complication of type 2 diabetes marked by extreme hyperglycemia and dehydration without ketosis.

What type of diabetes is HHS most common in?

Type 2 diabetes mellitus.

What is the main difference between DKA and HHS?

DKA has ketosis and acidosis; HHS does not.

What is the typical blood glucose level in HHS?

Usually greater than 600 mg/dL.

What is the serum osmolality in HHS?

Often exceeds 320 mOsm/kg.

Why are ketones absent in HHS?

There is enough circulating insulin to prevent fat breakdown.

What precipitating factors can cause HHS?

Infection, illness, dehydration, and undiagnosed diabetes.

What is the hallmark of HHS?

Severe dehydration and hyperosmolarity.

What are the neurologic symptoms of HHS?

Lethargy, seizures, and coma due to cellular dehydration.

What is the major cause of death in HHS?

Circulatory collapse or thromboembolic events.

What IV fluid is used first in HHS management?

0.9% normal saline for volume resuscitation.

How is insulin administered in HHS?

Low-dose IV insulin infusion similar to DKA.

Why is insulin requirement lower in HHS than in DKA?

Patients with HHS have partial insulin production.

What electrolyte must be monitored during HHS management?

Potassium, due to osmotic diuresis and insulin therapy.

When should dextrose be added to fluids in HHS?

When blood glucose reaches 250-300 mg/dL.

What is the main difference in acid-base balance between DKA and HHS?

DKA has metabolic acidosis; HHS has near-normal pH and bicarbonate.

What is the nursing priority in HHS?

Restore hydration and prevent thromboembolism.

Which population is at higher risk for HHS?

Older adults with type 2 diabetes and poor fluid intake.

Why is HHS often diagnosed late?

Symptoms develop gradually over several days.

What is the main cause of dehydration in HHS?

Osmotic diuresis due to extremely high blood glucose.

What neurological assessment is critical in HHS?

Monitor for seizures and mental status changes.

What are key nursing diagnoses for DKA and HHS?

Deficient fluid volume, risk for electrolyte imbalance, and knowledge deficit.

What vital sign indicates hypovolemia in DKA/HHS?

Low blood pressure and rapid, weak pulse.

What urine finding supports DKA diagnosis?

Positive ketones.

Why do DKA patients have fruity breath odor?

Presence of acetone from fat metabolism.

What lab value indicates resolution of DKA?

Normal anion gap and pH >7.3.

What is an important nursing goal in both DKA and HHS?

Maintain fluid balance and restore normal serum glucose.

What education should be given about insulin during illness?

Never skip insulin doses; monitor glucose and ketones frequently.

What should diabetic patients do when unable to eat during illness?

Consume fluids with carbohydrates to prevent ketosis.

What is the "sick-day rule" for diabetics?

Continue insulin, monitor blood sugar, increase fluids, and seek help for persistent vomiting.

What complication can occur with rapid fluid correction in DKA/HHS?

Cerebral edema.

How can hypoglycemia be prevented during DKA treatment?

Add dextrose when blood glucose falls below 250 mg/dL.

What nursing intervention ensures safe insulin therapy?

Use an infusion pump and monitor glucose hourly.

What signs indicate potassium imbalance in DKA/HHS?

Muscle weakness, arrhythmias, and ECG changes.

What should be monitored before giving potassium IV?

Ensure adequate urine output (>30 mL/hr).

Why should bicarbonate use be limited in DKA?

It may cause hypokalemia and paradoxical CNS acidosis.

What is the long-term prevention of DKA and HHS?

Adherence to insulin therapy, glucose monitoring, and early infection treatment.

What is the mortality rate comparison between DKA and HHS?

HHS has a higher mortality rate due to older age and comorbidities.

What electrolyte abnormality is most dangerous in DKA/HHS?

Hypokalemia.

What nursing outcome indicates effective therapy?

Stable vital signs, alertness, normal labs, and controlled glucose.