DKA
DKA made clear: what it is, how it develops, classic signs, and the nursing priorities — fluids, insulin, and potassium — at the bedside.
What is DKA? Diabetic Ketoacidosis
Diabetic Ketoacidosis (DKA) is a life-threatening emergency and a major complication of diabetes. It happens when your body doesn't have enough insulin to allow blood sugar into your cells for use as energy.
- Who gets it? Most common in Type 1 Diabetes, but it can occur in Type 2 Diabetes during periods of extreme illness or stress. It can also be the first sign of undiagnosed Type 1 diabetes.
DKA is defined by a triad of problems:
- Hyperglycaemia (High blood sugar)
- Ketosis (Ketones in the blood/urine)
- Metabolic Acidosis (Too much acid in the blood)
The Pathophysiology (The “Why”)
Understanding the “why” is key to understanding the treatment. It all starts with a severe lack of insulin.
1) Hyperglycaemia
- Without insulin, glucose can't get into the cells to be used for energy. It just builds up in the bloodstream.
- The body thinks it's starving, so the liver makes even more glucose (gluconeogenesis).
- Result: Blood sugar levels skyrocket (>11 mmol/L or 250 mg/dL). The high sugar concentration pulls water out of cells, causing osmotic diuresis and severe dehydration.
2) Ketosis & Acidosis
- Since cells are starving for glucose, the body breaks down fat for energy (lipolysis).
- The byproduct of fat breakdown is ketones (acidic).
- When ketones build up faster than they are cleared, blood pH drops → metabolic acidosis.
- Acetone, a ketone, is exhaled → classic fruity / nail polish remover breath.
3) Dehydration & Electrolyte Mayhem
- Osmotic diuresis causes large losses of water and electrolytes (K⁺, Na⁺, phosphate).
🚨 POTASSIUM IS CRITICAL! Initially, serum K⁺ may look normal or high because acidosis drives it out of cells. Total body K⁺ is low. When insulin therapy starts, K⁺ shifts back into cells → rapid, dangerous fall in serum K⁺ (hypokalaemia).
Causes & Triggers (The “5 S’s”)
- Sepsis (or any infection) — the most common cause
- Sickness (stomach bug, flu, MI, stroke)
- Stress (surgery, major physical or emotional trauma)
- Skipping Insulin (missed doses, pump failure, incorrect technique)
- Substance Abuse (especially alcohol)
- May be the initial presentation of undiagnosed Type 1 Diabetes
Signs & Symptoms
- Classic “3 P’s”
- Polyuria — excessive urination
- Polydipsia — excessive thirst
- Polyphagia — excessive hunger (often absent due to nausea)
- Acidosis
- Kussmaul respirations — deep, rapid, sighing breaths (blowing off CO₂)
- Fruity/acetone breath
- Nausea, vomiting, severe abdominal pain
- Dehydration
- Hypotension, tachycardia
- Dry mucous membranes, poor skin turgor
- Neurological
- Lethargy, confusion, drowsiness → may progress to coma
Nursing Management & Priorities
1) Fluid Resuscitation (Priority #1!)
- Start: Large volumes of 0.9% Normal Saline (isotonic) to restore organ perfusion.
- When to change: When glucose ~14 mmol/L (≈250 mg/dL), switch to fluid with dextrose (e.g., D5 in 0.45% Saline).
- Why: Prevent hypoglycaemia while insulin continues to fix the acidosis — you are treating the acidosis, not just the sugar.
2) Insulin Therapy (Stop the Ketones)
- How: Continuous IV insulin (Fixed Rate Insulin Infusion — FRII).
- Goal: Stop ketogenesis and gradually lower glucose.
- Caution: Lower glucose slowly (≈3–4 mmol/L per hour) to avoid cerebral oedema.
- Critical rule: Do not stop the insulin infusion until acidosis resolves (anion gap closed). Overlap with long-acting subcutaneous insulin for 1–2 hours before stopping IV insulin.
3) Electrolyte Management (Watch Potassium)
- Monitor: Electrolytes, especially K⁺, every 2–4 hours.
- Anticipate: Most patients need IV potassium added to fluids as insulin drives K⁺ into cells.
- Cardiac monitoring: Telemetry for potassium-related arrhythmias (peaked T-waves for high K⁺; flattened T/U waves for low K⁺).
Ongoing Nursing Care & Monitoring
- Hourly: Capillary glucose, vital signs, neurological status (GCS), urine output (strict I&O).
- Labs q2–4h: VBG and electrolytes — track pH, bicarbonate, and anion gap for resolution.
- Education (sick day rules):
- Never stop insulin, even if you can’t eat.
- Check blood glucose and ketones frequently.
- Stay hydrated with sugar-free fluids.
- Know when to call a clinician or go to hospital.