Diabetic Ketoacidosis (DKA) - Complete EMT Guide

1. DEFINITION

ADA 2024 Update: The updated June 2024 ADA Consensus Report introduced revised diagnostic and resolution criteria for DKA and HHS, as well as new recommendations for assessment and management. [PMID 40032308]

2. PATHOPHYSIOLOGY (Why It Happens)

1. Lipolysis pathway: Insulin deficiency activates hormone-sensitive lipase → increased free fatty acids (FFA) → FFA enter the liver → converted to ketone bodies (β-hydroxybutyrate, acetoacetate, acetone) → ketoacidosis
2. Hyperglycemia pathway: Cells cannot uptake glucose → blood glucose rises → exceeds renal threshold → glycosuria → osmotic diuresis → loss of water, sodium, potassium, magnesium, phosphorus, chloride → profound dehydration and electrolyte depletion
3. Proteolysis pathway: Muscle breaks down amino acids → liver uses them for gluconeogenesis → worsens hyperglycemia → worsens osmotic diuresis

• Rosen's Emergency Medicine, 9th Ed.

3. CAUSES / PRECIPITANTS

• Corticosteroids
• SGLT-2 inhibitors (e.g., empagliflozin, dapagliflozin) - can cause euglycemic DKA (glucose may be < 250!)
• Antipsychotics (clozapine, olanzapine)
• Thiazide diuretics
• Sympathomimetics
• Goldman-Cecil Medicine, Table 210-11

4. SIGNS & SYMPTOMS

Onset (typically gradual over 12-24 hours)

• Polyuria - excessive urination (from osmotic diuresis)
• Polydipsia - excessive thirst
• Polyphagia - increased hunger (early)
• Nausea and vomiting
• Abdominal pain - seen in ~50% of patients, especially children; in adults, consider this as a sign of an underlying precipitant
• Weakness and fatigue
• Visual blurring
• Weight loss

DKA Severity Classification (ADA 2024)

• Goldman-Cecil Medicine, Table 210-12

5. CLINICAL ASSESSMENT FOR EMTs

Scene Size-Up & Primary Survey

• Scene safety - ensure safe environment; note any insulin/medication bottles, glucometer
• General impression - patient may appear ill, diaphoretic, or confused
• Airway - assess; unconscious patients at risk for aspiration (especially if vomiting)
• Breathing - note rate, depth; Kussmaul breathing is a key finding
• Circulation - assess skin color/moisture/temperature; radial pulse quality; signs of shock

History (SAMPLE)

• S - Symptoms: nausea, vomiting, abdominal pain, polyuria, polydipsia, weakness
• A - Allergies to medications (especially insulin)
• M - Medications: insulin type/dose, any recent changes; SGLT-2 inhibitors; steroids
• P - Past history of diabetes (Type 1 or 2), previous DKA episodes
• L - Last oral intake; last insulin dose taken
• E - Events: recent illness, infection, stress, trauma, medication non-compliance

Physical Assessment (Focused)

• BP: look for hypotension or orthostatic drop
• HR: tachycardia is expected
• RR: Kussmaul breathing (deep and rapid)
• SpO2: usually normal unless pulmonary complication
• Temperature: fever suggests infection as precipitant

• The cornerstone EMT assessment tool
• DKA: typically > 250 mg/dL (but can be lower with SGLT-2 inhibitors or partial treatment)
• Document the exact reading

• Alert? Responsive to voice? Pain? Unresponsive?
• Altered mental status = higher severity, faster transport

6. MANAGEMENT - EMT Scope of Practice

EMT-Basic (BLS) Actions

1. Ensure scene safety and BSI (Standard Precautions - wear gloves)
2. Primary survey and stabilize ABCs
3. Administer oxygen to maintain SpO2 ≥ 94%
   • Do NOT suppress Kussmaul breathing with high-flow oxygen unless hypoxic - this breathing is compensatory
4. Obtain blood glucose level via glucometer (if approved by agency Medical Director)
   • If BG < 60 mg/dL with AMS → treat as hypoglycemia instead
5. Position the patient: semi-Fowler's if alert; recovery position if unconscious/vomiting
6. Do NOT delay transport - DKA requires hospital-level treatment (IV fluids, insulin, electrolyte monitoring)
7. Call for ALS intercept if the patient has:
   • Unstable vital signs
   • Altered mental status
   • Positive sepsis screen (lactate ≥ 2, suspected infection)
8. Provide oral hydration (water only) IF: patient is alert, can swallow, and is not vomiting
9. Monitor closely during transport - mental status, breathing, vitals

ALS / Paramedic Actions (scope for reference)

• Adults: 1,000 mL isotonic crystalloid (Normal Saline or Lactated Ringer's) IV/IO bolus; reassess and repeat if indicated
• Pediatrics: 20 mL/kg NS bolus during first hour
• If in hypovolemic shock: administer as rapidly as possible until SBP > 80 mmHg
• Average fluid deficit is 3-5 liters in adults
• ⚠️ Use 10 mL/kg bolus in pediatric patients to reduce risk of cerebral edema (NJ EMS Protocol 2025)
• Recent meta-analysis (2024) supports balanced electrolyte solutions (e.g., LR) over 0.9% saline for faster DKA resolution [PMID 38925619]

• Potassium is likely total-body depleted (even if serum K appears normal/high due to acidosis)
• Do NOT give insulin until potassium ≥ 3.3 mEq/L - insulin drives K into cells and can cause life-threatening hypokalemia
• Add 20-40 mEq KCl per liter of fluid once K < 5.5 mEq/L and renal function is adequate

• 0.1 units/kg/hour regular insulin IV infusion
• Switch IV fluid to D5W/0.45% NS when glucose ≤ 300 mg/dL (to prevent hypoglycemia while continuing insulin)
• Reduce to 0.05 units/kg/hour when glucose ≤ 250 mg/dL AND ketones < 1.0 mmol/L

• Avoid intubation if at all possible - patients have tremendous respiratory drive; matching minute ventilation with a ventilator is extremely difficult
• Intubate only if patient is comatose or vomiting with inability to protect airway
• If intubated: maintain hyperventilation to prevent worsening acidosis

7. KEY EMT PEARLS & RED FLAGS

• Fruity breath + high BG + Kussmaul breathing = DKA until proven otherwise
• Do NOT give insulin in the field - dangerous without potassium monitoring
• Hyperglycemia worsens brain ischemia - be extra cautious in patients with concurrent stroke, cardiac arrest, or head trauma
• SGLT-2 inhibitor patients may have euglycemic DKA (BG < 250) - don't rule out DKA on BG alone if clinical picture fits
• Fever is NOT caused by DKA itself - always suspect infection as the trigger if temperature is elevated
• Abdominal pain in adults = consider real abdominal pathology triggering DKA (not just a DKA symptom)
• Bicarbonate is NOT routinely given - only considered if pH < 7.0 and not responding to fluids/insulin
• DKA patients on hemodialysis may not have osmotic diuresis and can present atypically

8. DIFFERENTIAL DIAGNOSIS

9. DOCUMENTATION CHECKLIST FOR EMTs

• Blood glucose reading (with time)
• Mental status on arrival and at handoff
• Respiratory rate and pattern (note Kussmaul breathing if present)
• Breath odor (fruity/acetone)
• Vital signs (BP, HR, RR, SpO2, Temp if available)
• Skin assessment (turgor, moisture, color)
• Last insulin dose and time
• Last oral intake
• Medications (especially SGLT-2 inhibitors or steroids)
• Oral fluids given en route (if applicable)
• ALS intercept requested/obtained (Y/N)
• Oxygen administered (rate/delivery device)

• Rosen's Emergency Medicine: Concepts and Clinical Practice, 9th Ed. (Chapter 115, DKA section)
• Goldman-Cecil Medicine International Edition (Chapter 210, Table 210-11/12)
• NJ EMS Clinical Practice Protocols & Guidelines v1.0, August 2025 (Protocol 2.7A - Diabetic Emergencies: Hyperglycemia)
• 2024 ADA Consensus Report on Hyperglycemic Crises - Rodriguez Alvarez et al., Cleveland Clinic Journal of Medicine, 2025 [PMID 40032308]
• Szabó et al. (2024) - Balanced electrolyte solutions vs. 0.9% saline in DKA (Meta-Analysis) [PMID 38925619]