Severe Hyperglycemia — 520 mg/dL | 74 kg | 50-year-old

Step 1: Immediate Assessment — Determine the Syndrome

Step 2: Stat Workup

• BMP / Chem-7 (Na⁺, K⁺, Cl⁻, HCO₃⁻, BUN, Cr, glucose)
• Serum ketones / β-hydroxybutyrate
• Arterial blood gas (ABG) — pH, bicarbonate
• Serum osmolality — calculate: 2×Na + glucose/18 + BUN/2.8
• CBC with differential (leukocytosis ≠ infection in DKA — only bandemia suggests infection)
• Urinalysis (ketones, infection)
• Lipase (if abdominal pain present)
• ECG (hypokalemia/hyperkalemia risk)
• Chest X-ray (precipitating pneumonia?)
• HbA1c (establishes baseline, confirms diagnosis if new)
• Blood cultures if febrile

⚠️ Critical: Do NOT start insulin until you know the potassium level. Insulin drives K⁺ into cells — starting insulin with K⁺ <3.3 mEq/L can cause fatal arrhythmia.

Step 3: IV Access and Immediate Resuscitation

Fluids (start immediately, regardless of DKA vs. HHS)

Step 4: Insulin Protocol (after K⁺ confirmed ≥3.3 mEq/L)

DKA Protocol:

• Bolus: 0.1 units/kg regular insulin IV = 7.4 units IV push
• Infusion: 0.1 units/kg/h regular insulin = 7.4 units/hour IV
  • (Mix: 100 units regular insulin in 100 mL 0.9% NS → run at 7.4 mL/h)
• Target drop: 50–75 mg/dL per hour
• ⚠️ Do NOT correct >100 mg/dL/h (cerebral edema risk)
• When glucose reaches 250 mg/dL: Reduce insulin to 0.05 units/kg/h and add D5W bag

HHS Protocol:

• Lower insulin doses are often effective; fluids alone may drop glucose substantially
• Start insulin at 0.05–0.1 units/kg/h after fluid resuscitation begun
• Correct glucose slowly — rapid correction risks cerebral edema and worsening neurologic status

Step 5: Potassium Replacement

Step 6: Monitor Closely

Step 7: Find and Treat the Precipitant

• Infection (sepsis, pneumonia, UTI) — most common; start broad-spectrum antibiotics if suspected
• Medication non-compliance or missed insulin
• MI or stroke (especially in HHS — always get ECG)
• New-onset diabetes
• Surgery, trauma, pancreatitis

Step 8: When to Admit

Step 9: Resolution Criteria & Transition to SQ Insulin

• Glucose <250 mg/dL
• Bicarbonate ≥15 mEq/L
• Anion gap closed

Summary Algorithm

Glucose 520 mg/dL
       ↓
STAT labs + ECG + cultures
       ↓
Start 0.9% NS 1-2L IV immediately
       ↓
Check K⁺:
  <3.3 → Replace K⁺, hold insulin
  ≥3.3 → Start regular insulin 0.1 u/kg IV bolus + 0.1 u/kg/h
       ↓
Glucose ≤250 → Add D5W, reduce insulin
       ↓
Hourly glucose / Q2-4h electrolytes
       ↓
Treat precipitant | Admit to hospital

⚕️ Disclaimer: This is clinical decision support. Always apply individual patient context, local protocols, and senior physician judgment — particularly for critically ill patients.

Short Answer: It Depends on the Clinical Situation

Why a Flat 14 Units SC Is Problematic

When SC Insulin IS Acceptable in Hyperglycemia

Correct Approach for This Patient

1. Get K⁺ and ketones first (10–15 min with point-of-care)
2. Start 0.9% NS 1 L IV immediately — don't wait for labs for fluids
3. Once K⁺ ≥3.3 and if DKA confirmed:
   • Actrapid 7.4 units IV bolus + 7.4 units/hour IV infusion (0.1 u/kg each)
4. If labs show no ketoacidosis and patient is alert/hemodynamically stable:
   • A SC correction dose is acceptable — typically 0.1 u/kg SC = ~7 units, not 14

Bottom line: 14 units SC Actrapid is too much, too fast, and given without critical safety information (K⁺). At 520 mg/dL, always check labs first, start IV fluids, then use IV insulin at proper weight-based dosing. SC is acceptable only in mild/non-acidotic cases.

📋 ECG Understanding — Common Changes Explained Simply

First: What is an ECG?

         R
         |
    P    |         T
   / \   |        / \
--/   \--+-------/   \-----
          \     /
           Q   S

• Heart rate: 60–100 bpm
• PR interval: 0.12–0.20 sec (3–5 small boxes)
• QRS duration: <0.12 sec (<3 small boxes)
• QT interval: <0.44 sec (corrected)

🔴 Change 1 — STEMI (Heart Attack with ST Elevation)

• ST segment rises above the baseline like a "tombstone" or "coved" shape
• Seen in specific leads depending on which artery is blocked
• Reciprocal changes — ST depression in opposite leads (mirror image)
• Later: Q waves develop (= dead tissue), T wave inverts

Anterior STEMI — ST elevation in V1–V6 with reciprocal ST depression in inferior leads (II, III, aVF)

🟠 Change 2 — NSTEMI / Ischemia (ST Depression + T-wave Inversion)

• ST segment dips below the baseline (ST depression ≥0.5–1 mm)
• T wave inverts (flips upside down) — called T-wave inversion
• No ST elevation
• Deep symmetric T-wave inversions in V2–V3 = Wellens' syndrome (LAD critically stenosed — danger!)

🟡 Change 3 — Atrial Fibrillation (AF)

• No P waves — replaced by irregular fibrillatory (f) waves (wavy baseline)
• Irregularly irregular rhythm — R-R intervals are ALL different lengths
• QRS complexes are narrow (unless bundle branch block present)
• Fast ventricular rate (100–160 bpm if uncontrolled)

AF — no organized P waves, completely irregular R-R intervals, fibrillatory baseline

🟡 Change 4 — Ventricular Tachycardia (VT)

• Rate >100 bpm (usually 150–250 bpm)
• Wide, broad, bizarre QRS complexes (>0.12 sec = >3 small boxes)
• No visible P waves (or P waves dissociated from QRS)
• Regular rhythm
• Looks like a "fast, wide, ugly" tracing

VT — rapid, wide QRS complexes with no visible P waves

🟢 Change 5 — Heart Block (AV Block)

1st Degree AV Block

• PR interval >0.20 sec (>5 small boxes)
• Every P wave still conducts to a QRS
• Usually benign

2nd Degree — Mobitz I (Wenckebach)

• PR interval gets longer and longer with each beat until a QRS is dropped
• Then cycle resets
• "Longer, longer, longer… drop. Then you have a Wenckebach."

2nd Degree — Mobitz II

• PR interval is constant, then suddenly a P wave occurs with no QRS (dropped beat)
• More dangerous — can progress to complete block
• Requires pacemaker

3rd Degree (Complete Heart Block)

• No relationship between P waves and QRS complexes
• P waves march at their own rate, QRS complexes march at their own (slower) rate
• Ventricular escape rate: 20–40 bpm → very slow, dangerous
• Patient needs an emergency pacemaker

Complete heart block — P waves and QRS occur independently, ventricular rate is very slow

🔵 Change 6 — Hyperkalemia (High Potassium)

Progressive hyperkalemia ECG: peaked T waves → QRS widening → sine wave pattern (Harrison's Internal Medicine)

🔵 Change 7 — Left Ventricular Hypertrophy (LVH)

• Tall R waves in left-sided leads (V5, V6, aVL) + deep S waves in right leads (V1, V2)
• Sokolow-Lyon criteria: S in V1 + R in V5 or V6 >35 mm
• "Strain pattern" — ST depression + T-wave inversion in V5–V6 (lateral leads)

🔵 Change 8 — Bundle Branch Block

🔵 Change 9 — Pulmonary Embolism (PE)

• Sinus tachycardia (most common finding — ~40% of PE)
• Classic but rare: S1Q3T3 — deep S in lead I, Q wave in III, inverted T in III
• Right heart strain: RBBB, right axis deviation
• T-wave inversions in V1–V4 (right ventricular strain pattern)

🔵 Change 10 — Pericarditis

• Diffuse ST elevation in almost all leads (not just one territory) — saddle-shaped, concave up
• PR depression (very specific for pericarditis)
• No reciprocal ST depression (unlike MI)
• No Q waves

Quick Reference Summary