const pptxgen = require("pptxgenjs");

const pres = new pptxgen();
pres.layout = "LAYOUT_16x9";
pres.title = "Acute Hyponatremia: Evaluation, Management & Treatment Guidelines";
pres.author = "Clinical Education";

// ─── COLOR PALETTE ───────────────────────────────────────────────
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  midBlue:    "1A3A6C",   // card backgrounds / header bars
  accent:     "2196F3",   // accent lines, icons, highlights
  teal:       "00BCD4",   // secondary accent
  orange:     "FF7043",   // warning / danger callouts
  white:      "FFFFFF",
  offWhite:   "F0F4FA",
  lightGray:  "E8EDF5",
  textDark:   "1A1A2E",
  textMid:    "3A4A6A",
  green:      "43A047",
  yellow:     "FDD835",
};

// ─── HELPERS ─────────────────────────────────────────────────────
function titleSlide(slide, title, subtitle) {
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}

// ═══════════════════════════════════════════════════════════════════
// SLIDE 1 — TITLE
// ═══════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  titleSlide(s,
    "Acute Hyponatremia:\nEvaluation, Management\n& Treatment Guidelines",
    "Updated Evidence-Based Approach | 2025 - 2026"
  );
  s.addText("Serum Na⁺ < 135 mEq/L | Developed within 48 hours | Medical Emergency",
    { x: 0.45, y: 5.05, w: 9.1, h: 0.4, fontSize: 11, color: "A0B4C8", italic: true, align: "left" });
}

// ═══════════════════════════════════════════════════════════════════
// SLIDE 2 — DEFINITION & CLASSIFICATION
// ═══════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  contentBg(s);
  slideTitle(s, "Definition & Classification of Hyponatremia");

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    s.addText([
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      { text: "Serum Na⁺ < 135 mEq/L. ", options: { color: C.white } },
      { text: "Acute:", options: { bold: true, color: C.teal } },
      { text: " onset within 48 hours.", options: { color: C.white } },
      { text: "  Chronic: ", options: { bold: true, color: C.teal } },
      { text: "> 48 hours (or unknown duration)", options: { color: C.white } }
    ], { x: 0.42, y: 0.95, w: 9.2, h: 0.55, fontSize: 11.5, valign: "middle" });
  }

  // Severity table
  const sevData = [
    ["Severity", "Na⁺ Level", "Symptoms"],
    ["Mild",     "130–134 mEq/L", "Often asymptomatic"],
    ["Moderate", "125–129 mEq/L", "Nausea, headache, confusion"],
    ["Severe",   "< 125 mEq/L",  "Seizures, coma, herniation"],
  ];
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    firstRowFill: { color: C.midBlue }, color: C.white
  });

  // Volume classification boxes
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    { title: "Hypovolemic", color: C.orange, bullets: ["Vomiting / diarrhea", "Diuretics (thiazides)", "Adrenal insufficiency", "Salt-wasting nephropathy"] },
    { title: "Euvolemic", color: C.accent, bullets: ["SIADH (most common)", "Psychogenic polydipsia", "Hypothyroidism", "Exercise-associated"] },
    { title: "Hypervolemic", color: C.midBlue, bullets: ["Heart failure", "Cirrhosis", "Nephrotic syndrome", "Renal failure"] },
  ];
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  });

  s.addText("Volume classification drives diagnosis & treatment choice", {
    x: 0.3, y: 5.42, w: 9.4, h: 0.2, fontSize: 9.5, italic: true, color: C.textMid, align: "center"
  });
}

// ═══════════════════════════════════════════════════════════════════
// SLIDE 3 — CAUSES & PATHOPHYSIOLOGY
// ═══════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  contentBg(s);
  slideTitle(s, "Causes & Pathophysiology of Acute Hyponatremia");

  // Key causes boxes
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    "Postoperative hypotonic IV fluids (premenopausal women at risk)",
    "MDMA/Ecstasy — induces both thirst and AVP",
    "Exercise-associated hyponatremia (marathons, endurance events)",
    "Psychogenic polydipsia / water intoxication",
    "Iatrogenic: TURP glycine irrigation, tap water enemas",
    "Intracranial pathology with elevated ICP"
  ], C.accent);

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    "↓ Plasma tonicity → osmotic gradient → water enters brain cells",
    "Cerebral edema within rigid skull → ↑ ICP",
    "CNS initial response: efflux of Na⁺, K⁺, Cl⁻ from neurons",
    "Overwhelmed → acute hyponatremic encephalopathy",
    "Hypoxia amplifies injury (neurogenic pulmonary edema)",
    "Brainstem herniation → death if untreated"
  ], C.midBlue);

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    { label: "Non-osmotic stimuli", text: "Pain, nausea, stress, hypoxia → ↑ ADH release" },
    { label: "SIADH", text: "Inappropriate ADH → free water retention → dilutional hyponatremia" },
    { label: "Acute onset", text: "< 48 h: brain has not adapted via organic osmolyte loss" },
    { label: "Risk", text: "Premenopausal women — estrogen sensitizes brain to osmotic injury" },
  ];
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    s.addText([
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      { text: item.text, options: { color: C.textDark } }
    ], { x: bx + 0.12, y: by, w: 4.26, h: 0.58, fontSize: 10.5, valign: "middle" });
  });
}

// ═══════════════════════════════════════════════════════════════════
// SLIDE 4 — CLINICAL EVALUATION (SYMPTOMS & DIAGNOSIS)
// ═══════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  contentBg(s);
  slideTitle(s, "Clinical Evaluation: Symptoms & Initial Work-up");

  // Symptoms gradient severity
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  s.addText("MILD (Na⁺ 130–134)", { x: 0.3, y: 0.9, w: 4.5, h: 0.38, fontSize: 11, bold: true, color: C.white, align: "center" });
  const mildSx = ["Nausea, headache", "Fatigue, malaise", "Often asymptomatic"];
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  });

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  s.addText("SEVERE (Na⁺ < 125)", { x: 5.1, y: 0.9, w: 4.5, h: 0.38, fontSize: 11, bold: true, color: C.white, align: "center" });
  const sevSx = ["Vomiting, confusion", "Seizures, stupor, coma", "Respiratory failure (neurogenic)", "Brainstem herniation", "Death"];
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    s.addText("• " + t, { x: 5.22, y: 1.3 + i * 0.32, w: 4.2, h: 0.3, fontSize: 10.5, color: C.textDark });
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  // Divider
  s.addShape(pres.ShapeType.line, { x: 4.85, y: 0.9, w: 0, h: 1.9, line: { color: C.lightGray, width: 1.5, dashType: "dash" } });

  // Diagnostic work-up table
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  s.addText("Diagnostic Work-Up", { x: 0.3, y: 2.98, w: 9.4, h: 0.36, fontSize: 12, bold: true, color: C.white, align: "center" });

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    ["Test", "Finding in Hyponatremia", "Purpose"],
    ["Serum Na⁺, osmolality", "< 135 mEq/L; Posm < 275 mOsm/kg", "Confirm true vs pseudo-hyponatremia"],
    ["Urine osmolality", "> 100 mOsm/kg → ADH active", "Distinguish SIADH from polydipsia"],
    ["Urine Na⁺", "> 40 mEq/L = SIADH; < 20 = volume depletion", "Volume status assessment"],
    ["BUN, creatinine, glucose", "Elevated BUN/Cr → renal cause", "Exclude metabolic/renal causes"],
    ["Thyroid, cortisol, LFTs", "Rule out hypothyroid, Addison's, cirrhosis", "Identify treatable cause"],
  ];
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    x: 0.3, y: 3.36, w: 9.4, h: 2.08,
    fill: { color: C.white }, border: { color: C.lightGray, pt: 1 },
    fontFace: "Calibri", fontSize: 9.5,
    rowH: 0.36,
    firstRowFill: { color: C.darkNavy }, color: C.white
  });
}

// ═══════════════════════════════════════════════════════════════════
// SLIDE 5 — DIAGNOSTIC ALGORITHM
// ═══════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  contentBg(s);
  slideTitle(s, "Diagnostic Algorithm for Hyponatremia (European Guideline Approach)");

  // Step-by-step algorithm
  const steps = [
    { num: "1", title: "Confirm true hyponatremia", detail: "Serum Na⁺ < 135 mEq/L + Serum osmolality < 275 mOsm/kg\n(Exclude pseudo-hyponatremia: hyperlipidemia, hyperproteinemia, hyperglycemia)" },
    { num: "2", title: "Assess urine osmolality", detail: "Uosm < 100 mOsm/kg: primary polydipsia, low solute intake (beer potomania)\nUosm ≥ 100 mOsm/kg: ADH-dependent (proceed to step 3)" },
    { num: "3", title: "Assess volume status + urine Na⁺", detail: "Hypovolemic (UNa < 20): GI losses, burns | Euvolemic (UNa > 40): SIADH\nHypervolemic (UNa < 20): heart failure, cirrhosis | (UNa > 40): renal failure" },
    { num: "4", title: "SIADH: apply Bartter-Schwartz criteria", detail: "Hypo-osmolality + urine not maximally dilute (Uosm > 100) + euvolemic\n+ normal renal, adrenal, thyroid function + UNa > 40 mEq/L" },
  ];

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    s.addText(st.num, { x: 0.3, y: by + 0.12, w: 0.62, h: 0.62, fontSize: 16, bold: true, color: C.white, align: "center" });
    // connector arrow
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      s.addShape(pres.ShapeType.line, { x: 0.61, y: by + 0.74, w: 0, h: 0.38, line: { color: C.accent, width: 1.5 } });
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    // title bar
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  });
}

// ═══════════════════════════════════════════════════════════════════
// SLIDE 6 — SIADH (Dedicated)
// ═══════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  contentBg(s);
  slideTitle(s, "SIADH — Most Common Cause of Euvolemic Hyponatremia");

  bulletBox(s, 0.3, 0.92, 4.55, 2.45, "Bartter-Schwartz Diagnostic Criteria", [
    "Serum hypo-osmolality (< 275 mOsm/kg)",
    "Urine osmolality > 100 mOsm/kg (not maximally dilute)",
    "Clinical euvolemia (no edema, orthostasis)",
    "Urine Na⁺ > 40 mEq/L on normal sodium intake",
    "Normal thyroid, adrenal, renal function",
    "No recent diuretic use"
  ], C.midBlue);

  bulletBox(s, 5.15, 0.92, 4.55, 2.45, "Common SIADH Causes", [
    "CNS: meningitis, subarachnoid hemorrhage, stroke",
    "Pulmonary: pneumonia, TB, mechanical ventilation",
    "Malignancy: SCLC (10–15%), head & neck tumors",
    "Drugs: SSRIs, carbamazepine, cyclophosphamide, vincristine, NSAIDs",
    "Postoperative state (esp. premenopausal women)",
    "MDMA/Ecstasy, pain, nausea, stress"
  ], C.accent);

  // SIADH subtypes
  s.addShape(pres.ShapeType.rect, { x: 0.3, y: 3.5, w: 9.4, h: 0.36, fill: { color: C.midBlue }, line: { color: C.midBlue } });
  s.addText("SIADH Subtypes (by ADH pattern)", { x: 0.3, y: 3.5, w: 9.4, h: 0.36, fontSize: 11, bold: true, color: C.white, align: "center" });

  const subtypes = [
    ["Type A", "Erratic / autonomous ADH secretion"],
    ["Type B", "Reset osmostat — lower threshold for ADH release"],
    ["Type C", "Constant low-level ADH — flat response curve"],
    ["Type D", "SIADH without elevated ADH — AVP-independent mechanism"],
  ];
  subtypes.forEach((st, i) => {
    const bx = 0.3 + (i % 2) * 4.75;
    const by = 3.9 + Math.floor(i / 2) * 0.62;
    s.addShape(pres.ShapeType.rect, { x: bx, y: by, w: 4.5, h: 0.55, fill: { color: i % 2 === 0 ? C.lightGray : C.white }, line: { color: C.lightGray } });
    s.addText([
      { text: st[0] + ": ", options: { bold: true, color: C.accent } },
      { text: st[1], options: { color: C.textDark } }
    ], { x: bx + 0.1, y: by, w: 4.3, h: 0.55, fontSize: 10.5, valign: "middle" });
  });
}

// ═══════════════════════════════════════════════════════════════════
// SLIDE 7 — ACUTE MANAGEMENT: PRINCIPLES & EMERGENT TREATMENT
// ═══════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  contentBg(s);
  slideTitle(s, "Acute Management: Emergency Treatment Protocol");

  // Emergency banner
  s.addShape(pres.ShapeType.rect, { x: 0.3, y: 0.9, w: 9.4, h: 0.48, fill: { color: C.orange }, line: { color: C.orange } });
  s.addText("EMERGENCY: Symptomatic Acute Hyponatremia (Seizures / Coma / Herniation) → START 3% NaCl IMMEDIATELY", {
    x: 0.3, y: 0.9, w: 9.4, h: 0.48, fontSize: 12, bold: true, color: C.white, align: "center"
  });

  // 3 steps
  const steps = [
    { label: "STEP 1 — Bolus", color: C.orange, text: "3% NaCl 150 mL IV bolus over 20 minutes\nRepeat up to 2× if symptoms persist (total 450 mL)\nTarget: raise Na⁺ by 4–6 mEq/L per bolus" },
    { label: "STEP 2 — Reassess", color: C.accent, text: "Re-check serum Na⁺ within 20–30 min\nExpect ~1–2 mEq/L rise per 100 mL 3% NaCl bolus\nMonitor neurologic status continuously" },
    { label: "STEP 3 — Continue/Switch", color: C.midBlue, text: "Once symptoms resolve: switch to continuous infusion\nTarget 24h correction: 4–8 mEq/L (max 10 mEq/L)\nNEVER exceed 10–12 mEq/L in 24h (ODS risk)" },
  ];
  steps.forEach((st, i) => {
    const bx = 0.3 + i * 3.18;
    bulletBox(s, bx, 1.48, 3.0, 1.72, st.label, st.text.split("\n"), st.color);
  });

  // Correction rate table
  s.addShape(pres.ShapeType.rect, { x: 0.3, y: 3.3, w: 9.4, h: 0.36, fill: { color: C.darkNavy }, line: { color: C.darkNavy } });
  s.addText("Safe Sodium Correction Rate Guidelines", { x: 0.3, y: 3.3, w: 9.4, h: 0.36, fontSize: 11.5, bold: true, color: C.white, align: "center" });

  const rateData = [
    ["Scenario", "Target Rate", "24h Maximum", "Risk if Exceeded"],
    ["Acute symptomatic (< 48h)", "1–2 mEq/L/h initially", "4–8 mEq/L (up to 10)", "Generally safe to correct faster"],
    ["Chronic or unknown duration", "0.5–1 mEq/L/h", "Max 8 mEq/L/24h", "Osmotic Demyelination Syndrome (ODS)"],
    ["High ODS risk patients*", "< 0.5 mEq/L/h", "Max 6 mEq/L/24h", "Severe ODS with locked-in syndrome"],
  ];
  s.addTable(rateData, {
    x: 0.3, y: 3.68, w: 9.4, h: 1.75,
    fill: { color: C.white }, border: { color: C.lightGray, pt: 1 },
    fontFace: "Calibri", fontSize: 9.8,
    rowH: 0.4,
    firstRowFill: { color: C.midBlue }, color: C.white
  });
  s.addText("*High ODS risk: Na⁺ < 105, hypokalemia, alcohol use, malnutrition, advanced liver disease", {
    x: 0.3, y: 5.45, w: 9.4, h: 0.2, fontSize: 9, color: C.textMid, italic: true
  });
}

// ═══════════════════════════════════════════════════════════════════
// SLIDE 8 — SODIUM REPLACEMENT FORMULAS
// ═══════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  contentBg(s);
  slideTitle(s, "Sodium Correction Formulas & Fluid Selection");

  // Adrogue-Madias formula
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    { text: "(Total Body Water + 1)", options: { color: C.teal, bold: true } },
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    ["3% NaCl (hypertonic)", "513", "Acute symptomatic hyponatremia, seizures", "~1–2 mEq/L (100 mL bolus)"],
    ["0.9% NaCl (isotonic)", "154", "Hypovolemic hyponatremia", "Slower, unpredictable rise"],
    ["0.45% NaCl (hypotonic)", "77", "Avoid in hyponatremia — worsens it", "CONTRAINDICATED"],
    ["Lactated Ringer's", "130", "Hypovolemic states (near-isotonic)", "Slight Na⁺ rise"],
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    "Check serum Na⁺ every 2–4 h during active correction | Urine output and urine Na⁺/osmolality every 4–6 h",
    "If overcorrection occurs: stop 3% NaCl | Give D5W 3 mL/kg/h + desmopressin 2–4 mcg IV to re-lower Na⁺",
    "Supplemental O₂ and ventilatory support ready — respiratory failure common in acute hyponatremic encephalopathy"
  ], C.midBlue);
}

// ═══════════════════════════════════════════════════════════════════
// SLIDE 9 — ODS: OSMOTIC DEMYELINATION SYNDROME
// ═══════════════════════════════════════════════════════════════════
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  slideTitle(s, "Osmotic Demyelination Syndrome (ODS) — Formerly Central Pontine Myelinolysis");

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    "Hypokalemia (K⁺ co-depletion worsens risk)",
    "Alcohol use disorder / malnutrition",
    "Advanced liver disease (esp. pre-transplant)",
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    "Movement disorders, behavioral changes",
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    "Limit correction to ≤ 8 mEq/L in first 24h, ≤ 18 mEq/L in 48h",
    "If overcorrection detected: immediately give desmopressin (DDAVP) 2–4 mcg IV + D5W to re-lower Na⁺",
    "Proactive desmopressin strategy: give 1–2 mcg IV q6–8h to control correction rate while 3% NaCl infuses",
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// ═══════════════════════════════════════════════════════════════════
// SLIDE 10 — PHARMACOLOGICAL TREATMENT
// ═══════════════════════════════════════════════════════════════════
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  slideTitle(s, "Pharmacological Treatment Options");

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      bullets: ["IV only; hospital use for euvolemic/hypervolemic hyponatremia", "Loading: 20 mg IV over 30 min, then 20 mg/24h infusion", "Max 4 days; CYP3A4 inhibitor — multiple drug interactions", "Do not use in hypovolemic hyponatremia"]
    },
    {
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      bullets: ["Demeclocycline 300–600 mg BID: blocks ADH action at kidney (delayed 3–7 days)", "Urea (15–60 g/day PO): increases solute excretion; low-cost SIADH option", "Both used for chronic SIADH when fluid restriction fails", "Nephrotoxicity risk with demeclocycline in liver disease"]
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    { text: "Salt tablets (1–2 g TID):", options: { bold: true, color: C.midBlue } },
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// ═══════════════════════════════════════════════════════════════════
// SLIDE 11 — SPECIAL SCENARIOS
// ═══════════════════════════════════════════════════════════════════
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      points: ["Develops during/after endurance events (4–6h exercise)", "Cause: excessive hypotonic fluid intake + non-osmotic AVP rise", "Mild: fluid restriction (allow autofluids to work)", "Severe (seizures): 3% NaCl 100 mL IV bolus × 3 over 1h — safe even when duration uncertain"]
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      title: "Postoperative Hyponatremia", color: C.accent,
      points: ["Premenopausal women most vulnerable (estrogen effect)", "Often from hypotonic IV fluids + surgical stress AVP", "Prevention: use isotonic saline perioperatively", "Treatment: 3% NaCl for symptomatic cases; restrict free water input"]
    },
    {
      title: "MDMA/Ecstasy-Induced", color: C.orange,
      points: ["MDMA causes potent thirst + maximal ADH release", "Can develop to Na⁺ < 115 in hours — rapidly fatal", "Treatment: 3% NaCl urgently; ICU monitoring", "Women > men for encephalopathy risk"]
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      points: ["Extreme dilution despite relatively small water intake", "Urine osmolality very low (< 100 mOsm/kg), Urine Na⁺ < 10", "Saline/diet correction → risk of RAPID overcorrection (osmotic release)", "Monitor Na⁺ q2h; have desmopressin ready to slow correction"]
    },
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// ═══════════════════════════════════════════════════════════════════
// SLIDE 12 — NEW EVIDENCE & UPDATES 2024–2026
// ═══════════════════════════════════════════════════════════════════
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  slideTitle(s, "New Evidence & Guidelines Update 2024–2026");

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    { text: "Rapid correction (≥8 mEq/L/24h) was associated with 32 fewer in-hospital deaths per 1000 patients vs slow correction — ", options: { color: C.white } },
    { text: "AND did NOT increase ODS risk (Ayus JC et al., PMID 39556338)", options: { color: C.teal, italic: true } }
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      text: "Current evidence challenges the strict < 10 mEq/L/24h rule for acute hyponatremia. In true acute onset (< 48h), faster correction appears safe — ODS risk is primarily a chronic hyponatremia concern. Guidelines are shifting toward symptom-based targets."
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      text: "A 2026 systematic review (Schneider et al., J Gen Intern Med, PMID 41652262): Overcorrection in chronic hyponatremia remains harmful. Rescue with desmopressin + D5W is effective and should be standard protocol when Na⁺ rises > 10 mEq/L in 24h."
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      text: "Administer desmopressin prophylactically in high-risk patients alongside 3% NaCl to clamp correction rate. Growing evidence supports this approach to prevent inadvertent overcorrection, especially in beer potomania, thiazide-induced, and adrenal insufficiency cases."
    },
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      icon: "4", title: "Vaptans — Updated Role", color: C.green,
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// ═══════════════════════════════════════════════════════════════════
// SLIDE 13 — SUMMARY / TAKE-HOME POINTS
// ═══════════════════════════════════════════════════════════════════
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    { num: "01", text: "Acute hyponatremia (< 48h) is a medical emergency — cerebral edema risk before brain adaptation occurs" },
    { num: "02", text: "First step: confirm true hyponatremia → measure serum osmolality, urine Na⁺, urine osmolality, volume status" },
    { num: "03", text: "Symptomatic acute hyponatremia → 3% NaCl 150 mL IV bolus over 20 min (repeat ×2); target +4–6 mEq/L" },
    { num: "04", text: "Safe correction: ≤ 10–12 mEq/L in 24h (acute) | ≤ 8 mEq/L in 24h (chronic) to prevent ODS" },
    { num: "05", text: "ODS rescue: DDAVP 2–4 mcg IV + D5W 3 mL/kg/h — must respond within minutes of overcorrection" },
    { num: "06", text: "SIADH → fluid restriction + salt tablets; add tolvaptan or urea for refractory cases (not in liver disease)" },
    { num: "07", text: "2025 JAMA meta-analysis: faster correction associated with lower mortality without increased ODS — guidelines evolving" },
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// ─── WRITE FILE ──────────────────────────────────────────────────
pres.writeFile({ fileName: "/home/daytona/workspace/hyponatremia-ppt/Acute_Hyponatremia_Presentation.pptx" })
  .then(() => console.log("DONE: Acute_Hyponatremia_Presentation.pptx created"))
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Successfully replaced 1 instance(s) of the string in '/home/daytona/workspace/hyponatremia-ppt/build.js'

Successfully replaced 1 instance(s) of the string in '/home/daytona/workspace/hyponatremia-ppt/build.js'