CC | DKA & HHS

1. DM Classification & Core Diagnostics

• Type 1 DM: Autoimmune β-cell destruction (HLA-DR3/DR4) causing absolute insulin deficiency; presents abruptly with classic 3 Ps (polyuria, polydipsia, polyphagia), weight loss, and DKA risk[1][2].
• Type 2 DM: Insulin resistance combined with relative β-cell deficiency and inappropriate hepatic glucose production[3]. Onset is gradual[4].
• Diagnostic Criteria: A1C ≥6.5%, Fasting Plasma Glucose ≥126 mg/dL, 2-hr OGTT ≥200 mg/dL, or Random Glucose ≥200 mg/dL with classic symptoms[5]. Glycemic target A1C is <7.0%[6].

2. High-Yield Pharmacotherapy & Insulin Dynamics

• Insulin Types: Rapid-acting (lispro, aspart; onset 10–30 min, mealtime bolus), Short-acting (Regular; onset 30–60 min, only IV insulin), Intermediate (NPH; peaks 4–12 hr, cloudy), Long-acting (glargine, detemir; peakless basal)[7].
• Basal-Bolus Strategy: Optimal plan mimicking normal endogenous insulin secretion[7].
• Key Oral Agents: Metformin (Biguanide) reduces hepatic glucose output[10]. Safety Alert: Discontinue metformin 48 hr before/after IV contrast to prevent acute kidney injury and lactic acidosis[10][11]. Sulfonylureas (glipizide) stimulate insulin release and carry high hypoglycemia risk[11][12].

3. Hyperglycemic Emergencies: DKA vs. HHS

• DKA (T1DM): Absolute insulin deficiency → uncontrolled lipolysis → ketone bodies → metabolic acidosis (pH <7.30, HCO₃⁻ <16 mEq/L), Kussmaul respirations, fruity breath, glucose >250 mg/dL[13][14].
• HHS (T2DM): Enough circulating insulin prevents ketosis, but severe hyperglycemia (>600 mg/dL) causes osmotic diuresis, hyperosmolality, and profound neurologic deficits (coma, seizures)[15][16].
• Emergency Treatment Protocol:
  1. IV Fluids: First priority. 0.9% NaCl (1 L/hr) to maintain urine output (30–60 mL/hr)[14][15]. Add 5%–10% dextrose when glucose reaches ~250 mg/dL to prevent hypoglycemia and cerebral edema[14][15].
  2. Potassium: Check K⁺ BEFORE starting insulin. Insulin shifts K⁺ intracellularly, causing life-threatening hypokalemia if uncorrected[15].
  3. Continuous IV Regular Insulin: 0.1 U/kg/hr; target glucose reduction of 36–54 mg/dL/hr[15].

4. Hypoglycemia & Chronic Complications

• Hypoglycemia (<70 mg/dL): Treat via Rule of 15 (15–20g fast-acting carbs, recheck in 15 min)[16][17]. Unconscious: 20–50 mL 50% Dextrose IV or 1 mg Glucagon IM/SQ (turn on side to prevent aspiration)[17].
• Chronic Complications: Driven by angiopathy[18]. Macrovascular (CVD, stroke, PAD) managed via BP (<140/90) and lipid control[19]. Microvascular annual screening: Retinopathy (dilated eye exam), Nephropathy (urine albumin/creatinine; treat with ACEi/ARBs), and Neuropathy (monofilament test, daily foot inspection)[20].