const pptxgen = require("pptxgenjs");

const pres = new pptxgen();
pres.layout = "LAYOUT_16x9";
pres.author = "MD Anaesthesia";
pres.title = "Guedel's Stages of Anaesthesia";

// ─── COLOUR PALETTE ────────────────────────────────────────────
const C = {
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  deepBlue:   "102A4C",   // slide background alt
  midBlue:    "1565C0",   // section headers
  lightBlue:  "42A5F5",   // accent / highlight
  teal:       "00897B",   // stage III accent
  amber:      "FFB300",   // warning / Stage IV
  red:        "D32F2F",   // danger
  white:      "FFFFFF",
  offWhite:   "EEF4FB",
  silver:     "CFD8DC",
  textDark:   "0A1628",
  gold:       "F9A825",
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// ─── HELPER: add a header band ─────────────────────────────────
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// ─── HELPER: footer ────────────────────────────────────────────
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// ─── SLIDE 1: TITLE ────────────────────────────────────────────
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  s.addText("GUEDEL'S STAGES", {
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  s.addText("OF ANAESTHESIA", {
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    fontSize: 38, bold: true, color: C.lightBlue, charSpacing: 4, margin: 0
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  s.addText("A Comprehensive Review for MD Anaesthesia", {
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    fontSize: 14, italic: true, color: C.silver, margin: 0
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  s.addText("Arthur Ernest Guedel  |  1920 / 1937", {
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  addFooter(s, 1);
}

// ─── SLIDE 2: HISTORICAL BACKGROUND ───────────────────────────
{
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  s.background = { color: C.offWhite };
  addHeader(s, "Historical Background", "The Story Behind the Classification");

  const facts = [
    { icon: "◆", label: "Arthur Ernest Guedel (1883–1956)", detail: "American anaesthesiologist; classified depth of general anaesthesia" },
    { icon: "◆", label: "1920 — First publication", detail: "Based on observations using diethyl ether with morphine-atropine premedication" },
    { icon: "◆", label: "1937 — Expanded classification", detail: "Detailed system that gained universal acceptance; still the gold standard for conceptual teaching" },
    { icon: "◆", label: "Predecessors", detail: "John Snow (1847) & Francis Plomley first attempted to describe anaesthetic depth" },
    { icon: "◆", label: "Artusio (1954)", detail: "Further divided Stage I into 3 planes (plane 1: no analgesia/amnesia; plane 2: partial; plane 3: complete)" },
    { icon: "◆", label: "Modern relevance", detail: "Limited application with modern agents + NMBAs, but conceptually essential for understanding CNS depression" },
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// ─── SLIDE 3: OVERVIEW DIAGRAM ─────────────────────────────────
{
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  s.background = { color: C.navy };
  addHeader(s, "Overview: The Four Stages", "Depth of anaesthesia from induction → overdose");

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    { num: "I",   name: "ANALGESIA",          range: "Induction → Loss of consciousness",    color: "27AE60" },
    { num: "II",  name: "EXCITEMENT",         range: "Loss of consciousness → Auto breathing", color: "F39C12" },
    { num: "III", name: "SURGICAL ANAESTHESIA", range: "Auto breathing → Respiratory paralysis", color: C.midBlue },
    { num: "IV",  name: "MEDULLARY DEPRESSION", range: "Apnoea → Death",                     color: C.red },
  ];

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  s.addText("← LIGHTER                               INCREASING DEPTH OF ANAESTHESIA                               DEEPER →", {
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  addFooter(s, 3);
}

// ─── SLIDE 4: STAGE I ─────────────────────────────────────────
{
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  addHeader(s, "Stage I — Analgesia (Stage of Disorientation)", "From: Beginning of induction   →   To: Loss of consciousness");

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    ["Consciousness", "Patient is conscious and communicating; cooperative"],
    ["Analgesia", "Pain perception reduced; patient may feel touch but not pain sharply"],
    ["Amnesia", "Amnesia develops towards the end of this stage (late Stage I)"],
    ["Respiration", "Breathing normal; airway reflexes fully intact"],
    ["Eyes", "Pupils normal size; eyelid reflex present"],
    ["Reflexes", "All protective reflexes intact (cough, gag, swallow)"],
    ["Artusio's planes", "Plane 1: no analgesia/amnesia  |  Plane 2: partial  |  Plane 3: complete analgesia + amnesia"],
    ["Clinical use", "Nitrous oxide (70%) and low-dose IV agents can maintain Stage I — useful for minor procedures"],
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}

// ─── SLIDE 5: STAGE II ────────────────────────────────────────
{
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  addHeader(s, "Stage II — Excitement / Delirium", "From: Loss of consciousness   →   Onset of automatic (regular) breathing");

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    ["Consciousness", "Unconscious but CNS disinhibited — delirium, excitement"],
    ["Respiration", "Irregular; breath-holding episodes common; may have laryngospasm"],
    ["Eyes", "Eyelash reflex disappears; eyes may be open; eyeballs move randomly"],
    ["Muscle tone", "Increased; may have gross limb movements, clenched jaws"],
    ["Reflexes", "Exaggerated; cough, vomiting, laryngospasm — ALL intact and easily provoked"],
    ["Cardiovascular", "HR and BP increased; sympathetic stimulation"],
    ["Hazards", "Vomiting → aspiration; laryngospasm; breath-holding; cardiac arrhythmias"],
    ["Goal", "Pass through this stage as rapidly as possible — use high concentration induction agents"],
  ];

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  addFooter(s, 5);
}

// ─── SLIDE 6: STAGE III INTRO + PLANES OVERVIEW ───────────────
{
  const s = pres.addSlide();
  s.background = { color: C.navy };
  addHeader(s, "Stage III — Surgical Anaesthesia", "From: Onset of automatic breathing   →   Respiratory paralysis   |   4 Planes");

  s.addText("The most clinically important stage — site of all operative anaesthesia", {
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      key: "Eyelid reflex lost; swallowing disappears; eyeballs move",
      color: "1E88E5"
    },
    {
      num: "2", name: "Medium Surgical",
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      to: "Beginning of intercostal paralysis",
      key: "Laryngeal reflex lost; corneal reflex absent; lacrimation ↑ (light anaesthesia sign)",
      color: "1565C0"
    },
    {
      num: "3", name: "Deep Surgical",
      from: "Beginning of intercostal paralysis",
      to: "Complete intercostal paralysis",
      key: "Progressive intercostal ↓; diaphragm persists; pupils dilated; light reflex abolished",
      color: "0D47A1"
    },
    {
      num: "4", name: "Very Deep",
      from: "Complete intercostal paralysis",
      to: "Diaphragmatic paralysis (apnoea)",
      key: "Diaphragm stops → apnoea; danger zone approaching Stage IV",
      color: "B71C1C"
    },
  ];

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  addFooter(s, 6);
}

// ─── SLIDE 7: STAGE III — PLANES IN DETAIL (TABLE) ────────────
{
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  s.background = { color: C.offWhite };
  addHeader(s, "Stage III — Planes: Detailed Clinical Signs", "Respiratory, Ocular & Reflex Changes Across Each Plane");

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      fontSize: 10, bold: true, color: C.white, align: "center", valign: "middle", margin: 0
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    ["Respiration", "Regular, automatic", "Regular, ↓ volume", "Intercostal ↓, diaphragm only", "Apnoea (diaphragm stops)"],
    ["Eyeball movements", "Present (oscillating)", "Absent (fixed, central)", "Fixed, central", "Fixed, central"],
    ["Pupil size", "Normal / slight miosis", "Slightly dilated", "Dilated", "Maximally dilated"],
    ["Pupillary light reflex", "Present", "Present", "Abolished", "Abolished"],
    ["Eyelid reflex", "Absent", "Absent", "Absent", "Absent"],
    ["Conjunctival reflex", "Lost at bottom of plane", "Absent", "Absent", "Absent"],
    ["Corneal reflex", "Present", "Absent", "Absent", "Absent"],
    ["Lacrimation", "Present", "Increased (light sign)", "Decreased", "Absent"],
    ["Laryngeal reflex", "Present", "Lost", "Lost (anus/cervix only)", "Absent"],
    ["Swallowing reflex", "Lost at end", "Absent", "Absent", "Absent"],
    ["Muscle tone", "Slight ↓", "Relaxed", "Marked relaxation", "Complete flaccidity"],
  ];

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        valign: "middle", margin: 0
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    });
  });

  addFooter(s, 7);
}

// ─── SLIDE 8: STAGE III — GUEDEL'S EYE SIGNS ──────────────────
{
  const s = pres.addSlide();
  s.background = { color: C.navy };
  addHeader(s, "Stage III — Guedel's Eye Signs (Key Exam Topic)", "Ocular signs are the most reliable indicators of depth");

  const signs = [
    {
      title: "Eyeball Oscillation",
      desc: "Rhythmic, pendular movements present in Plane I of Stage III. Indicates safe plane for surgery.\nStops at start of Plane II — signifies deeper anaesthesia.",
      icon: "👁", color: "1E88E5"
    },
    {
      title: "Pupil Size & Reactivity",
      desc: "Miosis → normal in Stage I/II.\nProgressive mydriasis in Plane III–IV of Stage III and Stage IV.\nLoss of pupillary light reflex = Plane III (danger sign).",
      icon: "●", color: "00897B"
    },
    {
      title: "Lacrimation",
      desc: "Increased lacrimation (wet eyes) = light anaesthesia (Plane II).\nUseful bedside indicator that patient is too light.\nAbsent lacrimation in deep planes.",
      icon: "💧", color: "42A5F5"
    },
    {
      title: "Corneal Reflex",
      desc: "Present through Plane I.\nLost at start of Plane II.\nIts abolition = reliably indicates Plane II depth.",
      icon: "◉", color: "F9A825"
    },
    {
      title: "Eyelid (Palpebral) Reflex",
      desc: "Eyelash reflex lost at transition Stage II → Stage III.\nNot useful within Stage III planes.",
      icon: "—", color: "AB47BC"
    },
    {
      title: "Conjunctival Reflex",
      desc: "Lost at the bottom of Plane I.\nLess clinically used but marks deepening within Plane I.",
      icon: "◌", color: "EF5350"
    },
  ];

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  addFooter(s, 8);
}

// ─── SLIDE 9: STAGE IV ────────────────────────────────────────
{
  const s = pres.addSlide();
  s.background = { color: "1A0005" };

  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 0, w: 10, h: 1.1, fill: { color: C.red }, line: { color: C.red } });
  s.addShape(pres.shapes.RECTANGLE, { x: 0, y: 1.05, w: 10, h: 0.06, fill: { color: C.amber }, line: { color: C.amber } });
  s.addText("Stage IV — Medullary Depression / Overdose", {
    x: 0.35, y: 0.1, w: 9.3, h: 0.85,
    fontSize: 22, bold: true, color: C.white, margin: 0, valign: "middle"
  });
  s.addText("From: Stoppage of respiration   →   Death  |  THIS STAGE MUST NEVER BE REACHED CLINICALLY", {
    x: 0.35, y: 1.15, w: 9.3, h: 0.32,
    fontSize: 9.5, italic: true, color: C.amber, margin: 0
  });

  const pts = [
    ["Respiration", "Complete apnoea — diaphragm paralysed; no spontaneous breathing"],
    ["Cardiovascular", "Vasomotor centre in medulla depressed → profound hypotension, circulatory collapse"],
    ["Pupils", "Fixed, maximally dilated (mydriasis) — no light reflex"],
    ["Muscle tone", "Complete flaccidity"],
    ["CNS", "Severe medullary depression; death imminent without intervention"],
    ["Cause", "Anaesthetic overdose — excess agent concentration reaching brainstem"],
    ["Management", "Immediate: stop agent, 100% O₂, IPPV, vasopressors, CPR if needed"],
    ["Prevention", "Careful dose titration, end-tidal monitoring, BIS monitoring, SpO₂, ETCO₂"],
  ];

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  });

  addFooter(s, 9);
}

// ─── SLIDE 10: SIGNS SUMMARY TABLE ────────────────────────────
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  s.background = { color: C.offWhite };
  addHeader(s, "Summary: Signs Across All Stages", "Quick Reference — Reflexes, Respiration, Pupils, Muscles");

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    ["Consciousness", "Conscious", "Unconscious", "Unconscious", "Unconscious", "Unconscious"],
    ["Respiration", "Normal", "Irregular", "Regular, ↓", "Intercostal ↓", "Apnoea"],
    ["Eyelash reflex", "Present", "Absent", "Absent", "Absent", "Absent"],
    ["Pupil size", "Normal", "Normal/dilated", "Normal→mild ↑", "Dilated", "Max dilated"],
    ["Light reflex", "Present", "Present", "Present", "Absent", "Absent"],
    ["Corneal reflex", "Present", "Present", "Absent (P-II)", "Absent", "Absent"],
    ["Lacrimation", "Normal", "Normal/↑", "↑ (light sign)", "↓", "Absent"],
    ["Laryngeal reflex", "Present", "Present (exag.)", "Lost (P-II)", "Lost", "Absent"],
    ["Muscle tone", "Normal", "↑↑ (rigid)", "↓", "↓↓", "Flaccid"],
    ["Vomiting hazard", "No", "HIGH", "Low", "None", "None"],
  ];

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        color: ci === 0 ? C.midBlue : C.textDark,
        align: "center", valign: "middle", margin: 0
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      xi += colW2[ci];
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  addFooter(s, 10);
}

// ─── SLIDE 11: MODERN RELEVANCE & LIMITATIONS ─────────────────
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  const s = pres.addSlide();
  s.background = { color: C.offWhite };
  addHeader(s, "Modern Relevance & Limitations", "Why Guedel's Classification Still Matters — and Its Boundaries");

  // Left column: Limitations
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  const lims = [
    "Described for ether — slow onset allows observation of signs",
    "Modern agents (propofol, sevoflurane) have rapid induction; Stage II is brief or absent",
    "Neuromuscular blocking agents paralyse muscles — most signs undetectable",
    "Signs differ with IV vs inhalational agents",
    "Nitrous oxide does not produce all stages predictably",
    "Opioid premedication alters pupillary responses",
    "Not applicable to paediatric or geriatric patients without modification",
  ];
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      x: 0.3, y, w: 4.5, h: 0.38,
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    s.addText("✕  " + pt, {
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  // Right column: Modern relevance
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  const rels = [
    "Conceptual framework for understanding CNS depression depth",
    "Teaching tool for anaesthesia residents & students",
    "Basis for understanding signs of light/deep anaesthesia",
    "BIS monitor was developed from EEG correlates of Guedel stages",
    "Relevant when NMBAs not used (e.g. ENT, ophthalmic procedures)",
    "Pupil dilation still used as indicator of depth/pain response",
    "Stage IV signs (fixed dilated pupils, apnoea) = overdose diagnosis",
  ];
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    const y = 1.96 + i * 0.44;
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      x: 5.2, y, w: 4.5, h: 0.38,
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    });
    s.addText("✓  " + pt, {
      x: 5.28, y: y + 0.05, w: 4.35, h: 0.28,
      fontSize: 8.5, color: "0D47A1", margin: 0
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  });

  addFooter(s, 11);
}

// ─── SLIDE 12: SIGNS OF LIGHT vs DEEP ANAESTHESIA ─────────────
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  const s = pres.addSlide();
  s.background = { color: C.navy };
  addHeader(s, "Clinical Signs of Light vs Deep Anaesthesia", "Important for Intraoperative Assessment — High-Yield Exam Topic");

  // Light anaesthesia box
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  s.addText("⚠  LIGHT ANAESTHESIA", { x: 0.3, y: 1.52, w: 4.5, h: 0.38, fontSize: 12, bold: true, color: C.white, align: "center", valign: "middle", margin: 0 });
  const lightSigns = [
    "Swallowing / licking lips",
    "Lacrimation (tears in eyes)",
    "Purposeful movement",
    "Tachycardia & hypertension",
    "Diaphoresis (sweating)",
    "Laryngospasm / bronchospasm",
    "Breath-holding",
    "Eyelash reflex returns",
    "Increased muscle tone",
  ];
  lightSigns.forEach((pt, i) => {
    const y = 1.98 + i * 0.38;
    s.addShape(pres.shapes.RECTANGLE, {
      x: 0.3, y, w: 4.5, h: 0.33,
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    s.addText(pt, { x: 0.42, y: y + 0.06, w: 4.2, h: 0.22, fontSize: 9.5, color: "FFCC80", margin: 0 });
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  // Deep anaesthesia box
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  s.addText("⛔  DEEP / DANGEROUS ANAESTHESIA", { x: 5.2, y: 1.52, w: 4.5, h: 0.38, fontSize: 10, bold: true, color: C.white, align: "center", valign: "middle", margin: 0 });
  const deepSigns = [
    "Fixed, dilated pupils",
    "Absent light reflex",
    "Absent corneal reflex",
    "Absent lacrimation",
    "Intercostal paralysis / apnoea",
    "Hypotension & bradycardia",
    "Complete muscle flaccidity",
    "Absent all reflexes",
    "Medullary depression",
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    const y = 1.98 + i * 0.38;
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      x: 5.2, y, w: 4.5, h: 0.33,
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    s.addText(pt, { x: 5.32, y: y + 0.06, w: 4.2, h: 0.22, fontSize: 9.5, color: "FF8A80", margin: 0 });
  });

  addFooter(s, 12);
}

// ─── SLIDE 13: MNEMONICS & EXAM PEARLS ────────────────────────
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  const s = pres.addSlide();
  s.background = { color: C.offWhite };
  addHeader(s, "Exam Pearls & Mnemonics", "High-Yield Points for MD Anaesthesia Theory Examination");

  const pearls = [
    {
      tag: "MNEMONIC",
      color: C.midBlue,
      text: "Stages: \"All Exhausted Surgeons Die\" = Analgesia → Excitement → Surgical → Death (medullary)"
    },
    {
      tag: "PEARL 1",
      color: "27AE60",
      text: "Lacrimation ↑ = LIGHT anaesthesia (Plane II). Absent lacrimation = deep. Tears = lighten up!"
    },
    {
      tag: "PEARL 2",
      color: "8E24AA",
      text: "Eyeball oscillation is present in Plane I only — its cessation marks entry into Plane II"
    },
    {
      tag: "PEARL 3",
      color: "F4511E",
      text: "Stage II (Excitement) = most dangerous for aspiration and laryngospasm — never linger here"
    },
    {
      tag: "PEARL 4",
      color: "0097A7",
      text: "Corneal reflex lost = Plane II entry. Light reflex lost = Plane III (danger sign)"
    },
    {
      tag: "PEARL 5",
      color: "C0392B",
      text: "Plane III Stage III was the target for surgery before NMBAs. Today, Plane I-II (with NMBAs) suffices"
    },
    {
      tag: "PEARL 6",
      color: "1565C0",
      text: "Artusio's planes (1954) subdivide Stage I into 3 planes for N₂O / light IV anaesthesia"
    },
    {
      tag: "PEARL 7",
      color: "F9A825",
      text: "Fixed, maximally dilated pupils + apnoea = Stage IV = EMERGENCY. Stop agent, IPPV, resuscitate"
    },
  ];

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    const y = 1.52 + i * 0.5;
    s.addShape(pres.shapes.RECTANGLE, {
      x: 0.3, y, w: 1.1, h: 0.4,
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      x: 1.43, y, w: 8.27, h: 0.4,
      fill: { color: i % 2 === 0 ? "EEF4FB" : "FFFFFF" },
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    s.addText(p.text, {
      x: 1.55, y: y + 0.07, w: 8.0, h: 0.27,
      fontSize: 9.5, color: C.textDark, margin: 0
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  });

  addFooter(s, 13);
}

// ─── SLIDE 14: CLOSING / THANK YOU ────────────────────────────
{
  const s = pres.addSlide();
  s.background = { color: C.navy };

  s.addShape(pres.shapes.OVAL, { x: 6.5, y: -1, w: 5, h: 5, fill: { color: "1565C0", transparency: 80 }, line: { color: "1565C0", transparency: 80 } });
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  s.addShape(pres.shapes.RECTANGLE, { x: 0.5, y: 1.2, w: 0.08, h: 3.0, fill: { color: C.lightBlue }, line: { color: C.lightBlue } });

  s.addText("THANK YOU", {
    x: 0.8, y: 1.15, w: 8, h: 1,
    fontSize: 46, bold: true, color: C.white, charSpacing: 8, margin: 0
  });
  s.addText("Guedel's legacy: understanding that anaesthesia is a continuum,\nnot a binary on/off state.", {
    x: 0.8, y: 2.25, w: 8, h: 0.85,
    fontSize: 13, italic: true, color: C.silver, margin: 0
  });
  s.addText("References:", {
    x: 0.8, y: 3.3, w: 8, h: 0.3,
    fontSize: 10, bold: true, color: C.lightBlue, margin: 0
  });
  s.addText(
    "• Katzung's Basic & Clinical Pharmacology, 16th Ed. (Guedel's signs described under inhaled anaesthetics)\n" +
    "• Guedel AE. Inhalation Anesthesia: A Fundamental Guide. Macmillan, 1937\n" +
    "• Wikipedia — Guedel's Classification (Arthur Ernest Guedel, 1883–1956)\n" +
    "• Artusio JF. Di-ethyl ether analgesia. J Pharmacol Exp Ther. 1954",
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      x: 0.8, y: 3.63, w: 8.5, h: 1.3,
      fontSize: 8.5, color: C.silver, margin: 0
    }
  );

  addFooter(s, 14);
}

// ─── WRITE FILE ────────────────────────────────────────────────
pres.writeFile({ fileName: "/home/daytona/workspace/guedel-anaesthesia/Guedels_Stages_Anaesthesia_MD.pptx" })
  .then(() => console.log("✅ Presentation saved!"))
  .catch(err => { console.error("❌ Error:", err); process.exit(1); });

const pptxgen = require("pptxgenjs");
const pres = new pptxgen();
pres.layout = "LAYOUT_16x9";
pres.author = "MD Anaesthesia";
pres.title = "Autonomic Nervous System — Classification, Distribution & Clinical Tests";

// ─── COLOUR PALETTE ───────────────────────────────────────────
const C = {
  bg:       "0B1F3A",   // deep navy — dominant
  bgAlt:    "F0F4FA",   // off-white slides
  symp:     "C0392B",   // red — sympathetic
  sympLight:"FFEBEE",
  sympMid:  "E53935",
  para:     "1565C0",   // blue — parasympathetic
  paraLight:"E3F2FD",
  paraMid:  "1976D2",
  gold:     "F9A825",
  teal:     "00897B",
  tealLight:"E0F2F1",
  green:    "2E7D32",
  white:    "FFFFFF",
  silver:   "CFD8DC",
  dark:     "0B1F3A",
  text:     "1A2B40",
  purple:   "6A1B9A",
  purpleL:  "F3E5F5",
};

function hdr(s, title, sub) {
  s.addShape(pres.shapes.RECTANGLE, { x:0, y:0, w:10, h:1.05, fill:{color:C.bg}, line:{color:C.bg} });
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function ftr(s, n) {
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}

// ══════════════════════════════════════════════════════════════
// SLIDE 1 — TITLE
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bg };
  // decorative ovals
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  s.addText("AUTONOMIC NERVOUS SYSTEM", { x:0.82, y:1.25, w:8.5, h:0.85, fontSize:34, bold:true, color:C.white, charSpacing:3, margin:0 });
  s.addText("Classification  ·  Distribution  ·  Functions  ·  Clinical Tests", {
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  ftr(s, 1);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 2 — ANS OVERVIEW
// ══════════════════════════════════════════════════════════════
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  s.background = { color: C.bgAlt };
  hdr(s, "Overview: The Autonomic Nervous System", "Involuntary control of visceral, cardiovascular and glandular functions");

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    { label:"Definition", text:"The ANS controls involuntary (vegetative) functions — cardiovascular, respiratory, GI, urogenital, glandular. It operates below the level of consciousness via feedback loops.", color:C.bg },
    { label:"Divisions", text:"Sympathetic (Thoracolumbar: T1–L2/L3)  •  Parasympathetic (Craniosacral: CN III, VII, IX, X + S2–S4)  •  Enteric (ENS — often called the 'second brain')", color:C.teal },
    { label:"Neurotransmitters", text:"Sympathetic: Norepinephrine (NE) at end-organ; Acetylcholine (ACh) at ganglion  •  Parasympathetic: ACh at both ganglion AND end-organ", color:C.purple },
    { label:"Receptors", text:"Sympathetic: α1, α2 (post-gang.) and β1, β2, β3  •  Parasympathetic: M1–M5 (muscarinic)  •  Ganglionic (both): Nicotinic N₁", color:C.green },
    { label:"ANS & Anaesthesia", text:"Every general anaesthetic modifies ANS function. Understanding it is essential for managing haemodynamic instability, bradyarrhythmias, airway reflexes, and drug interactions.", color:C.symp },
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  ftr(s, 2);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 3 — SYMPATHETIC: ANATOMY & CLASSIFICATION
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bgAlt };
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    ["Origin", "Intermediolateral (IML) cell column of spinal cord — T1 to L2 (sometimes L3)"],
    ["Pre-ganglionic fibers", "Short myelinated B-fibers; release ACh at ganglia (nicotinic receptors)"],
    ["Ganglia", "Paravertebral (sympathetic chain — 22 pairs) and Prevertebral (celiac, superior/inferior mesenteric, aorticorenal)"],
    ["Post-ganglionic fibers", "Long unmyelinated C-fibers; release Norepinephrine (NE) at end-organs (α & β receptors). Exception: sweat glands & some blood vessels → ACh"],
    ["Adrenal medulla", "Special case — presynaptic sympathetic fibers innervate chromaffin cells directly; secrete Epinephrine (80%) + NE (20%) into circulation"],
    ["Central control", "Hypothalamus (posterior) → brainstem vasomotor centres → IML. Stimulation by stress, pain, hypoxia, hypovolaemia"],
    ["Nerve distribution", "Grey rami communicantes → all spinal nerves → peripheral distribution to blood vessels, sweat glands, arrector pili, viscera"],
  ];

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      x:0.5, y, w:9.2, h:0.47,
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  });
  ftr(s, 3);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 4 — SYMPATHETIC: DISTRIBUTION TO ORGANS
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bg };
  hdr(s, "Sympathetic Distribution — Organ by Organ", "Fight-or-Flight: Thoracolumbar Outflow Effects");

  const organs = [
    { organ:"Heart",          level:"T1–T5", effect:"HR ↑, Contractility ↑, Conduction velocity ↑, AV node conduction ↑" },
    { organ:"Blood Vessels",  level:"T1–L2", effect:"Vasoconstriction (α1) in skin/viscera; Vasodilation (β2) in skeletal muscle" },
    { organ:"Lungs/Bronchi",  level:"T1–T5", effect:"Bronchodilation (β2); ↓ secretions" },
    { organ:"Eye (Iris)",     level:"T1",    effect:"Mydriasis (radial muscle, α1); Retraction of upper lid" },
    { organ:"GI Tract",       level:"T6–L2", effect:"↓ motility, ↓ secretions; sphincter contraction (α1)" },
    { organ:"Liver",          level:"T7–T10",effect:"Glycogenolysis ↑, Gluconeogenesis ↑ (β2)" },
    { organ:"Kidney",         level:"T10–L1",effect:"Renin secretion ↑ (β1); renal vasoconstriction (α1)" },
    { organ:"Bladder",        level:"T10–L2",effect:"Detrusor relaxation (β2); internal sphincter contraction (α1) — urine retention" },
    { organ:"Adrenal Medulla",level:"T6–T10",effect:"Adrenaline (80%) + Noradrenaline (20%) secretion" },
    { organ:"Sweat Glands",   level:"T1–L2", effect:"↑ secretion (cholinergic sympathetic — ACh)" },
    { organ:"Skin/Pilomotors",level:"T1–L2", effect:"Vasoconstriction; arrector pili contraction (goosebumps)" },
    { organ:"Male Genitalia", level:"T10–L2",effect:"Ejaculation; seminal vesicle contraction" },
  ];

  const cols = [1.0, 2.7, 4.0];
  const colW = [1.6, 1.25, 5.5];
  const hdrs = ["Organ / Structure", "Level", "Sympathetic Effect"];
  const hBG = [C.symp, "B71C1C", "7B0000"];
  let xPos = 0.25;
  hdrs.forEach((h, i) => {
    s.addShape(pres.shapes.RECTANGLE, { x:xPos, y:1.52, w:colW[i], h:0.38, fill:{color:hBG[i]}, line:{color:hBG[i]} });
    s.addText(h, { x:xPos, y:1.52, w:colW[i], h:0.38, fontSize:9.5, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
    xPos += colW[i];
  });

  organs.forEach((r, i) => {
    const y = 1.9 + i*0.3;
    const bg = i%2===0 ? "3B0A10" : "260007";
    let x = 0.25;
    [r.organ, r.level, r.effect].forEach((cell, ci) => {
      s.addShape(pres.shapes.RECTANGLE, { x, y, w:colW[ci], h:0.27, fill:{color:bg}, line:{color:"5C0A14", pt:0.3} });
      s.addText(cell, { x:x+0.06, y:y+0.03, w:colW[ci]-0.1, h:0.2, fontSize:ci===1?8:8.5, bold:ci===0, color:ci===1?"FFAB91":ci===0?"FFCCBC":C.offWhite||"FAFAFA", margin:0, align:ci===1?"center":"left" });
      x += colW[ci];
    });
  });
  ftr(s, 4);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 5 — PARASYMPATHETIC: ANATOMY & CLASSIFICATION
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bgAlt };
  hdr(s, "Parasympathetic Division — Anatomy & Classification", "Craniosacral Outflow: CN III, VII, IX, X + S2–S4");

  s.addShape(pres.shapes.RECTANGLE, { x:0.28, y:1.48, w:0.12, h:3.7, fill:{color:C.para}, line:{color:C.para} });

  const rows = [
    ["Origin (Cranial)", "CN III (EW nucleus, midbrain)  •  CN VII (sup. salivatory nucleus, pons)  •  CN IX (inf. salivatory nucleus, medulla)  •  CN X (dorsal motor nucleus + nucleus ambiguus, medulla)"],
    ["Origin (Sacral)", "Lateral grey horn of S2–S4 — pelvic splanchnic nerves (nervi erigentes) → pelvic viscera and hindgut"],
    ["Pre-ganglionic fibers", "Long myelinated fibers; release ACh at terminal ganglia (nicotinic receptors)"],
    ["Ganglia location", "Close to or within the wall of the target organ (terminal/intramural ganglia). In head: ciliary, pterygopalatine, submandibular, otic ganglia"],
    ["Post-ganglionic fibers", "Very short unmyelinated fibers; release ACh at end-organs (muscarinic M1–M5 receptors)"],
    ["Central control", "Hypothalamus (anterior) → brainstem nuclei. Dominant during rest, feeding, digestion — 'Rest and Digest'"],
    ["Neurotransmitter", "ACh throughout (pre- AND post-ganglionic). Blocked by Atropine/Glycopyrrolate (anti-muscarinic)"],
  ];

  rows.forEach(([label, text], i) => {
    const y = 1.5 + i * 0.53;
    s.addShape(pres.shapes.RECTANGLE, {
      x:0.5, y, w:9.2, h:0.47,
      fill:{color: i%2===0 ? C.paraLight : "FFFFFF"},
      line:{color:"BBDEFB", pt:0.5}
    });
    s.addText(label+":", { x:0.6, y:y+0.09, w:2.1, h:0.28, fontSize:9.5, bold:true, color:C.para, margin:0 });
    s.addText(text, { x:2.75, y:y+0.09, w:6.85, h:0.28, fontSize:9.5, color:C.text, margin:0 });
  });
  ftr(s, 5);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 6 — PARASYMPATHETIC: DISTRIBUTION TO ORGANS
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bg };
  hdr(s, "Parasympathetic Distribution — Organ by Organ", "Rest & Digest: Craniosacral Outflow Effects");

  const organs = [
    { organ:"Eye",            nerve:"CN III (Ciliary)",       effect:"Miosis (sphincter pupillae); Accommodation (ciliary muscle)" },
    { organ:"Lacrimal Gland", nerve:"CN VII (Pterygopalatine)",effect:"↑ Lacrimation" },
    { organ:"Salivary Glands",nerve:"CN VII (Subman.), CN IX (Otic)",effect:"↑ Salivation (watery)" },
    { organ:"Nasal Mucosa",   nerve:"CN VII",                 effect:"↑ Secretion from nasal glands" },
    { organ:"Heart",          nerve:"CN X (Vagus)",           effect:"HR ↓ (SA node), AV conduction ↓, Contractility slight ↓" },
    { organ:"Lungs/Bronchi",  nerve:"CN X",                   effect:"Bronchoconstriction; ↑ bronchial secretions" },
    { organ:"GI Tract",       nerve:"CN X (foregut/midgut),\nS2-S4 (hindgut)",effect:"↑ motility, ↑ secretions; sphincter relaxation; peristalsis" },
    { organ:"Liver/Pancreas", nerve:"CN X",                   effect:"↑ Insulin, ↑ bile secretion, ↑ exocrine pancreas" },
    { organ:"Bladder",        nerve:"S2–S4 (Pelvic)",         effect:"Detrusor contraction; internal sphincter relaxation → micturition" },
    { organ:"Male Genitalia", nerve:"S2–S4",                  effect:"Erection (vasodilation of cavernous vessels)" },
    { organ:"Female Genitalia",nerve:"S2–S4",                 effect:"Vaginal lubrication; clitoral erection" },
    { organ:"Blood Vessels",  nerve:"Limited",                effect:"Vasodilation in specific vascular beds (e.g. erectile tissue) via NO" },
  ];

  const colW = [1.65, 2.0, 5.0];
  const hBG = [C.para, "0D47A1", "082A6F"];
  let xPos = 0.25;
  ["Organ", "Nerve (Origin)", "Parasympathetic Effect"].forEach((h, i) => {
    s.addShape(pres.shapes.RECTANGLE, { x:xPos, y:1.52, w:colW[i], h:0.38, fill:{color:hBG[i]}, line:{color:hBG[i]} });
    s.addText(h, { x:xPos, y:1.52, w:colW[i], h:0.38, fontSize:9.5, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
    xPos += colW[i];
  });

  organs.forEach((r, i) => {
    const y = 1.9 + i*0.3;
    const bg = i%2===0 ? "0D2A4A" : "0A1E36";
    let x = 0.25;
    [r.organ, r.nerve, r.effect].forEach((cell, ci) => {
      s.addShape(pres.shapes.RECTANGLE, { x, y, w:colW[ci], h:0.27, fill:{color:bg}, line:{color:"1A3A6A", pt:0.3} });
      s.addText(cell, { x:x+0.06, y:y+0.03, w:colW[ci]-0.1, h:0.2, fontSize:ci===1?8:8.5, bold:ci===0, color:ci===1?"90CAF9":ci===0?"BBDEFB":"FAFAFA", margin:0, align:ci===1?"center":"left" });
      x += colW[ci];
    });
  });
  ftr(s, 6);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 7 — COMPARISON TABLE: SNS vs PNS
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bgAlt };
  hdr(s, "Sympathetic vs Parasympathetic — Comparison", "Side-by-Side Classification | High-Yield Exam Table");

  const cols = ["Feature", "Sympathetic (SNS)", "Parasympathetic (PNS)"];
  const colW = [2.2, 3.75, 3.75];
  const hBG = [C.bg, C.symp, C.para];
  let xPos = 0.15;
  cols.forEach((c, i) => {
    s.addShape(pres.shapes.RECTANGLE, { x:xPos, y:1.5, w:colW[i], h:0.38, fill:{color:hBG[i]}, line:{color:hBG[i]} });
    s.addText(c, { x:xPos, y:1.5, w:colW[i], h:0.38, fontSize:10, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
    xPos += colW[i];
  });

  const rows = [
    ["Outflow level",       "Thoracolumbar (T1–L2/L3)",        "Craniosacral (CN III, VII, IX, X; S2–S4)"],
    ["Pre-ganglionic",      "Short; ACh → Nicotinic (ganglia)", "Long; ACh → Nicotinic (ganglia)"],
    ["Post-ganglionic",     "Long; NE → α/β receptors",         "Short; ACh → Muscarinic receptors"],
    ["Ganglion location",   "Paravertebral / Prevertebral",      "Terminal (near/in organ wall)"],
    ["Overall effect",      "Fight-or-Flight (Ergotropic)",       "Rest-Digest-Reproduce (Trophotropic)"],
    ["Heart rate",          "↑ HR, ↑ Contractility",             "↓ HR, slight ↓ contractility"],
    ["Bronchi",             "Dilation (β2)",                      "Constriction + ↑ secretions"],
    ["Pupils",              "Mydriasis (α1)",                     "Miosis"],
    ["GI motility",         "↓ (α1, β2)",                        "↑ (M3)"],
    ["Bladder",             "Relaxes detrusor; contracts sphincter","Contracts detrusor; relaxes sphincter"],
    ["Sweat glands",        "↑ (Cholinergic — exception!)",       "Not significant"],
    ["Blood vessels",       "Constriction (α1); ↑ BP",           "Dilation in select vascular beds"],
  ];

  rows.forEach((row, ri) => {
    let xi = 0.15;
    const ry = 1.88 + ri * 0.3;
    row.forEach((cell, ci) => {
      const bg = ri%2===0 ? (ci===0?"DDEEFF":ci===1?"FFF3F3":"F0F8FF") : (ci===0?"CCE0F5":ci===1?"FFFFFF":"FFFFFF");
      s.addShape(pres.shapes.RECTANGLE, { x:xi, y:ry, w:colW[ci], h:0.27, fill:{color:bg}, line:{color:"D0D8E8", pt:0.3} });
      s.addText(cell, { x:xi+0.05, y:ry+0.04, w:colW[ci]-0.08, h:0.19, fontSize:ci===0?9:8.5, bold:ci===0, color:ci===0?C.bg:ci===1?C.symp:C.para, margin:0 });
      xi += colW[ci];
    });
  });
  ftr(s, 7);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 8 — RECEPTORS & NEUROTRANSMITTERS
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bg };
  hdr(s, "Receptors & Neurotransmitters of the ANS", "Essential for Drug Mechanism Understanding in Anaesthesia");

  // Left panel: Adrenergic
  s.addShape(pres.shapes.RECTANGLE, { x:0.25, y:1.52, w:4.6, h:0.38, fill:{color:C.symp}, line:{color:C.symp} });
  s.addText("ADRENERGIC RECEPTORS (Sympathetic)", { x:0.25, y:1.52, w:4.6, h:0.38, fontSize:10, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });

  const adrRows = [
    { rec:"α1", loc:"Blood vessels, iris, bladder neck", effect:"Vasoconstriction; mydriasis; urinary retention", drugs:"Phenylephrine, Methoxamine" },
    { rec:"α2", loc:"Pre-synaptic terminals, CNS", effect:"↓ NE release (feedback); sedation; ↓ BP", drugs:"Clonidine, Dexmedetomidine" },
    { rec:"β1", loc:"Heart, JGA (kidney)", effect:"↑ HR, ↑ contractility, ↑ renin", drugs:"Dobutamine, Adrenaline" },
    { rec:"β2", loc:"Bronchi, blood vessels, uterus", effect:"Bronchodilation; vasodilation; uterine relaxation", drugs:"Salbutamol, Terbutaline" },
    { rec:"β3", loc:"Adipose tissue", effect:"Lipolysis", drugs:"Minor clinical relevance" },
  ];
  adrRows.forEach((r, i) => {
    const y = 1.95 + i*0.66;
    s.addShape(pres.shapes.RECTANGLE, { x:0.25, y, w:0.55, h:0.6, fill:{color:C.symp}, line:{color:C.symp} });
    s.addText(r.rec, { x:0.25, y, w:0.55, h:0.6, fontSize:14, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
    s.addShape(pres.shapes.RECTANGLE, { x:0.83, y, w:4.02, h:0.6, fill:{color:"1C0005"}, line:{color:"8B0000", pt:0.8} });
    s.addText(r.loc, { x:0.9, y:y+0.03, w:3.88, h:0.2, fontSize:8, bold:true, color:"FF8A80", margin:0 });
    s.addText(r.effect, { x:0.9, y:y+0.23, w:3.88, h:0.17, fontSize:8, color:C.white, margin:0 });
    s.addText("Drugs: "+r.drugs, { x:0.9, y:y+0.41, w:3.88, h:0.15, fontSize:7.5, italic:true, color:"FFCDD2", margin:0 });
  });

  // Right panel: Cholinergic
  s.addShape(pres.shapes.RECTANGLE, { x:5.15, y:1.52, w:4.6, h:0.38, fill:{color:C.para}, line:{color:C.para} });
  s.addText("CHOLINERGIC RECEPTORS (Parasympathetic)", { x:5.15, y:1.52, w:4.6, h:0.38, fontSize:10, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });

  const choRows = [
    { rec:"N1", loc:"Autonomic ganglia (all)", effect:"Ganglionic transmission (SNS + PNS)", drugs:"Blocked by: Trimethaphan (ganglion blocker)" },
    { rec:"N2", loc:"NMJ (skeletal muscle)", effect:"Muscle contraction (not ANS)", drugs:"Blocked by: Succinylcholine, Vecuronium" },
    { rec:"M1", loc:"CNS, gastric parietal", effect:"CNS excitation; ↑ gastric acid", drugs:"Pirenzepine (selective M1 blocker)" },
    { rec:"M2", loc:"Heart (SA/AV node)", effect:"↓ HR, ↓ AV conduction", drugs:"Blocked by: Atropine, Glycopyrrolate" },
    { rec:"M3", loc:"Smooth muscle, glands", effect:"Bronchoconstriction; ↑ secretions; GI ↑", drugs:"Blocked by: Ipratropium, Hyoscine" },
  ];
  choRows.forEach((r, i) => {
    const y = 1.95 + i*0.66;
    s.addShape(pres.shapes.RECTANGLE, { x:5.15, y, w:0.55, h:0.6, fill:{color:C.para}, line:{color:C.para} });
    s.addText(r.rec, { x:5.15, y, w:0.55, h:0.6, fontSize:14, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
    s.addShape(pres.shapes.RECTANGLE, { x:5.73, y, w:4.02, h:0.6, fill:{color:"081A40"}, line:{color:"1565C0", pt:0.8} });
    s.addText(r.loc, { x:5.8, y:y+0.03, w:3.88, h:0.2, fontSize:8, bold:true, color:"64B5F6", margin:0 });
    s.addText(r.effect, { x:5.8, y:y+0.23, w:3.88, h:0.17, fontSize:8, color:C.white, margin:0 });
    s.addText("Drugs: "+r.drugs, { x:5.8, y:y+0.41, w:3.88, h:0.15, fontSize:7.5, italic:true, color:"BBDEFB", margin:0 });
  });
  ftr(s, 8);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 9 — ANS & ANAESTHESIA: CLINICAL RELEVANCE
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bgAlt };
  hdr(s, "ANS & Anaesthesia — Clinical Relevance", "How ANS Modulation Underpins Everyday Anaesthetic Practice");

  const items = [
    { tag:"Induction", color:C.bg, text:"Propofol / thiopentone → ↓ SNS → vasodilation → hypotension; Ketamine → ↑ SNS (NE release) → hypertension, tachycardia" },
    { tag:"Laryngoscopy", color:C.symp, text:"Sympathetic storm: tachycardia, hypertension. Attenuated by opioids (fentanyl), β-blockers, lidocaine, Magnesium, α2-agonists" },
    { tag:"Volatile agents", color:C.teal, text:"Dose-dependent ↓ SNS output. Desflurane rapid ↑ → paradoxical SNS activation. Isoflurane ↓ SVR. Halothane ↓ contractility + sensitizes to catecholamines" },
    { tag:"Intubation reflexes", color:C.purple, text:"PNS (vagal): Bradycardia during intubation especially in children. Pre-treat with Atropine / Glycopyrrolate" },
    { tag:"Neostigmine", color:C.para, text:"Anti-ChE → ↑ ACh → bradycardia, bronchoconstriction. ALWAYS co-administer Atropine or Glycopyrrolate (anti-muscarinic)" },
    { tag:"Dexmedetomidine", color:C.green, text:"α2-agonist → ↓ SNS outflow → sedation, analgesia, ↓ shivering. Useful for awake fibreoptic, ICU sedation, attenuation of haemodynamic response" },
    { tag:"Spinal / Epidural", color:"E65100", text:"Sympathetic blockade → vasodilation, hypotension, bradycardia (if T1–T4 blocked). High block → Bezold-Jarisch reflex" },
    { tag:"Autonomic dysreflexia", color:C.symp, text:"SCIs above T6 → massive SNS discharge below lesion → severe hypertension. Triggered by bladder distension, pressure sores" },
  ];

  items.forEach((item, i) => {
    const y = 1.48 + i*0.5;
    s.addShape(pres.shapes.RECTANGLE, { x:0.25, y, w:1.5, h:0.43, fill:{color:item.color}, line:{color:item.color} });
    s.addText(item.tag, { x:0.25, y, w:1.5, h:0.43, fontSize:9.5, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
    s.addShape(pres.shapes.RECTANGLE, { x:1.78, y, w:7.97, h:0.43, fill:{color:"FFFFFF"}, line:{color:item.color, pt:0.8} });
    s.addText(item.text, { x:1.88, y:y+0.08, w:7.8, h:0.26, fontSize:9, color:C.text, margin:0 });
  });
  ftr(s, 9);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 10 — CLINICAL TESTS: OVERVIEW
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bg };
  hdr(s, "Clinical Tests to Evaluate the Autonomic Nervous System", "Standardised Battery for Sympathetic & Parasympathetic Function");

  s.addText("Autonomic function testing classifies dysfunction into: Cardiovagal (PNS) ·  Adrenergic (SNS)  ·  Sudomotor (SNS-cholinergic)", {
    x:0.3, y:1.52, w:9.4, h:0.35, fontSize:10, italic:true, color:C.gold, margin:0
  });

  const cats = [
    { cat:"CARDIOVAGAL (PNS)", color:C.para, tests:["Heart Rate variability with deep breathing (E:I ratio)", "Valsalva Manoeuvre — Valsalva Ratio", "30:15 Ratio (HR response to standing)", "Lying-to-standing HR ratio"] },
    { cat:"ADRENERGIC (SNS)", color:C.symp, tests:["BP response to Valsalva manoeuvre (phases)", "Tilt-table test (Passive Head-Up Tilt)", "Cold Pressor Test", "Sustained Isometric Handgrip Test", "BP response to standing"] },
    { cat:"SUDOMOTOR (SNS-Cholinergic)", color:C.teal, tests:["QSART — Quantitative Sudomotor Axon Reflex Test", "Thermoregulatory Sweat Test (TST)", "Sympathetic Skin Response (SSR)", "Skin temperature measurement"] },
    { cat:"SPECIAL / ADVANCED", color:C.gold, tests:["Plasma Catecholamines (NE, Adrenaline) — basal & stressed", "Pharmacological tests (Noradrenaline pressor test)", "Heart Rate Variability (HRV) Power Spectral Analysis", "Pupillometry; Microneurography (MSNA)"] },
  ];

  cats.forEach((c, i) => {
    const col = i % 2;
    const row = Math.floor(i / 2);
    const x = 0.25 + col * 4.85;
    const y = 1.97 + row * 1.72;
    s.addShape(pres.shapes.RECTANGLE, { x, y, w:4.6, h:0.35, fill:{color:c.color}, line:{color:c.color} });
    s.addText(c.cat, { x, y, w:4.6, h:0.35, fontSize:9.5, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
    c.tests.forEach((t, ti) => {
      const ty = y + 0.38 + ti*0.31;
      s.addShape(pres.shapes.RECTANGLE, { x, y:ty, w:4.6, h:0.28, fill:{color:ti%2===0?"0D2240":"0A1830"}, line:{color:c.color, pt:0.4} });
      s.addText("▸  "+t, { x:x+0.1, y:ty+0.04, w:4.4, h:0.2, fontSize:8.5, color:C.white, margin:0 });
    });
  });
  ftr(s, 10);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 11 — CARDIOVAGAL TESTS (PNS)
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bgAlt };
  hdr(s, "Cardiovagal Tests — Parasympathetic Function", "Based on Heart Rate Variability & Reflex Responses");

  const tests = [
    {
      name:"1. Deep Breathing Test (E:I Ratio)",
      normal:"E:I ratio ≥ 1.21 (age < 40 yr); approaches 1.04 at age > 60",
      method:"Patient breathes 6 breaths/min (5s in, 5s out). Record ECG. Calculate max:min HR ratio (= E:I ratio).",
      interp:"< 1.20 = mild dysfunction;  < 1.10 = severe PNS dysfunction",
      color:C.para
    },
    {
      name:"2. Valsalva Manoeuvre — Valsalva Ratio",
      normal:"≥ 1.5 (ratio of maximum HR during straining to minimum HR after release)",
      method:"Exhale against resistance (40 mmHg) for 15 s. Monitor HR beat-to-beat. Phase II: ↑ HR (SNS). Phase IV: ↓ HR (PNS).",
      interp:"Failure of HR ↑ in Phase II → SNS dysfunction. Failure of HR ↓ in Phase IV → PNS dysfunction",
      color:"0D47A1"
    },
    {
      name:"3. Lying-to-Standing (30:15 Ratio)",
      normal:"30:15 ratio ≥ 1.04",
      method:"Patient stands from lying. Record ECG. Fastest HR at beat 15 and slowest at beat 30 (reflex bradycardia).",
      interp:"Absent or reduced ratio = cardiovagal (PNS) impairment",
      color:"1976D2"
    },
    {
      name:"4. HRV Power Spectral Analysis",
      normal:"High-frequency (HF) component (0.15–0.4 Hz) reflects PNS; Low-frequency (LF) reflects SNS + PNS; LF:HF ratio = sympathovagal balance",
      method:"5-minute ECG recording; fast Fourier transform analysis of RR intervals",
      interp:"↓ HF power = ↓ PNS; ↑ LF:HF ratio = ↑ sympathetic dominance",
      color:C.teal
    },
  ];

  tests.forEach((t, i) => {
    const y = 1.5 + i*0.98;
    s.addShape(pres.shapes.RECTANGLE, { x:0.25, y, w:9.5, h:0.26, fill:{color:t.color}, line:{color:t.color} });
    s.addText(t.name, { x:0.35, y, w:9.3, h:0.26, fontSize:10, bold:true, color:C.white, margin:0, valign:"middle" });
    s.addShape(pres.shapes.RECTANGLE, { x:0.25, y:y+0.26, w:9.5, h:0.67, fill:{color:i%2===0?C.paraLight:"FFFFFF"}, line:{color:t.color, pt:0.5} });
    s.addText("Method: "+t.method, { x:0.4, y:y+0.29, w:9.2, h:0.2, fontSize:8.5, color:C.text, margin:0 });
    s.addText("Normal: "+t.normal, { x:0.4, y:y+0.51, w:4.5, h:0.18, fontSize:8.5, bold:true, color:C.green, margin:0 });
    s.addText("Interpretation: "+t.interp, { x:5.0, y:y+0.51, w:4.65, h:0.18, fontSize:8, color:C.symp, margin:0 });
  });
  ftr(s, 11);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 12 — ADRENERGIC TESTS (SNS)
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bgAlt };
  hdr(s, "Adrenergic Tests — Sympathetic Function", "Blood Pressure Responses to Standardised Stimuli");

  const tests = [
    {
      name:"1. Passive Head-Up Tilt Test (HUTT) / Orthostatic BP",
      normal:"Normal orthostatic response: HR ↑ ≤ 15 bpm, SBP ↓ < 10 mmHg",
      method:"Tilt to 60–80° for 10–45 min. Monitor BP & HR every minute. +/- Pharmacological provocation (Isoproterenol, GTN)",
      interp:"Orthostatic hypotension: SBP ↓ ≥ 20 or DBP ↓ ≥ 10 mmHg within 3 min → adrenergic failure",
      color:C.symp
    },
    {
      name:"2. Cold Pressor Test",
      normal:"↑ SBP 15–20 mmHg; ↑ DBP 10–15 mmHg within 1 min of cold immersion",
      method:"Immerse hand in ice water (4°C) for 1–5 min. Measure BP every 30 seconds.",
      interp:"Absent or blunted response = intact SNS vasomotor pathway failure",
      color:"B71C1C"
    },
    {
      name:"3. Sustained Isometric Handgrip Test",
      normal:"DBP rises ≥ 15 mmHg from baseline during sustained contraction",
      method:"Patient squeezes dynamometer at 30% maximal voluntary contraction for 3–5 min. Record BP.",
      interp:"Failure to raise DBP = adrenergic (SNS) dysfunction",
      color:"7B0000"
    },
    {
      name:"4. Valsalva BP Response (Phases)",
      normal:"Phase II: BP falls then stabilises (SNS vasoconstriction); Phase IV: BP overshoot (venous return + SNS)",
      method:"Same as Valsalva for PNS but focus on BP curve. Absence of Phase IV BP overshoot = SNS dysfunction",
      interp:"'Square wave' response (no BP fall/overshoot) = complete autonomic failure",
      color:"E53935"
    },
  ];

  tests.forEach((t, i) => {
    const y = 1.5 + i*0.98;
    s.addShape(pres.shapes.RECTANGLE, { x:0.25, y, w:9.5, h:0.26, fill:{color:t.color}, line:{color:t.color} });
    s.addText(t.name, { x:0.35, y, w:9.3, h:0.26, fontSize:10, bold:true, color:C.white, margin:0, valign:"middle" });
    s.addShape(pres.shapes.RECTANGLE, { x:0.25, y:y+0.26, w:9.5, h:0.67, fill:{color:i%2===0?"FFEBEE":"FFFFFF"}, line:{color:t.color, pt:0.5} });
    s.addText("Method: "+t.method, { x:0.4, y:y+0.29, w:9.2, h:0.2, fontSize:8.5, color:C.text, margin:0 });
    s.addText("Normal: "+t.normal, { x:0.4, y:y+0.51, w:4.5, h:0.18, fontSize:8.5, bold:true, color:C.green, margin:0 });
    s.addText("Interpretation: "+t.interp, { x:5.0, y:y+0.51, w:4.65, h:0.18, fontSize:8, color:"B71C1C", margin:0 });
  });
  ftr(s, 12);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 13 — SUDOMOTOR & SPECIAL TESTS
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bgAlt };
  hdr(s, "Sudomotor & Advanced Autonomic Tests", "Sweat Function & Specialised Investigations");

  const left = [
    {
      name:"QSART (Quantitative Sudomotor Axon Reflex Test)",
      text:"Iontophoresis of ACh into skin → activates sweat axon reflex → sweat output measured in a capsule (µL). Tests post-ganglionic sympathetic cholinergic C-fibers. Abnormal: ↓ or absent sweat output. Sensitive for early small-fibre neuropathy.",
      color:C.teal
    },
    {
      name:"Thermoregulatory Sweat Test (TST)",
      text:"Patient placed in heated environment until core temp rises 1°C. Body painted with indicator powder (alizarin red). Sweat revealed by colour change. Global map of anhidrosis vs normal sweating.",
      color:"00695C"
    },
    {
      name:"Sympathetic Skin Response (SSR)",
      text:"Electrodes on palm/sole. Unexpected stimulus (loud sound, median nerve shock) → galvanic skin response (sudomotor sympathetic). Normal: latency < 2 s (hand), < 2.5 s (foot). Absent/prolonged = SNS dysfunction.",
      color:"004D40"
    },
  ];
  const right = [
    {
      name:"Plasma Catecholamines",
      text:"NE, Adrenaline, Dopamine measured supine and after standing for 5 min. Normal: NE rises ≥ 100 pg/mL on standing. Flat response = adrenergic failure (e.g. PAF). High basal NE = normobaric sympathetic failure.",
      color:C.purple
    },
    {
      name:"Microneurography (MSNA)",
      text:"Direct recording of postganglionic sympathetic nerve activity via tungsten microelectrode in peroneal nerve. Gold standard for muscle sympathetic nerve activity (MSNA). Research use; rarely clinical.",
      color:"4A148C"
    },
    {
      name:"Composite Autonomic Scoring Scale (CASS)",
      text:"Validated scoring system (0–10) incorporating sudomotor + cardiovagal + adrenergic subscores. Mild: 1–3; Moderate: 4–6; Severe: 7–10. Used to monitor disease progression and treatment response.",
      color:C.gold.substring?C.gold:"F9A825"
    },
  ];

  [left, right].forEach((col, ci) => {
    const x = ci===0 ? 0.25 : 5.1;
    col.forEach((item, i) => {
      const y = 1.52 + i*1.28;
      s.addShape(pres.shapes.RECTANGLE, { x, y, w:4.6, h:0.3, fill:{color:item.color}, line:{color:item.color} });
      s.addText(item.name, { x, y, w:4.6, h:0.3, fontSize:9, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
      s.addShape(pres.shapes.RECTANGLE, { x, y:y+0.3, w:4.6, h:0.92, fill:{color:i%2===0?C.tealLight:"FFFFFF"}, line:{color:item.color, pt:0.7} });
      s.addText(item.text, { x:x+0.1, y:y+0.35, w:4.4, h:0.82, fontSize:8.5, color:C.text, margin:0 });
    });
  });
  ftr(s, 13);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 14 — AUTONOMIC NEUROPATHY & ANAESTHETIC IMPLICATIONS
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bg };
  hdr(s, "Autonomic Neuropathy — Anaesthetic Implications", "Pre-operative Assessment & Intraoperative Management");

  // Causes box
  s.addShape(pres.shapes.RECTANGLE, { x:0.25, y:1.52, w:4.55, h:0.32, fill:{color:C.symp}, line:{color:C.symp} });
  s.addText("CAUSES OF AUTONOMIC NEUROPATHY", { x:0.25, y:1.52, w:4.55, h:0.32, fontSize:10, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
  const causes = ["Diabetes mellitus (most common)", "Parkinson's disease / MSA / PAF", "Amyloidosis", "Guillain-Barré syndrome", "Porphyria", "Chronic alcoholism", "Uraemia (CKD)", "Autoimmune (SLE, SS)", "HIV neuropathy", "Drug-induced (Vinca alkaloids, Cisplatin)"];
  causes.forEach((c, i) => {
    const y = 1.87 + i*0.31;
    s.addShape(pres.shapes.RECTANGLE, { x:0.25, y, w:4.55, h:0.28, fill:{color:i%2===0?"1C0005":"0E0003"}, line:{color:"5C0A14", pt:0.3} });
    s.addText("• "+c, { x:0.4, y:y+0.04, w:4.3, h:0.2, fontSize:8.5, color:"FFB3AE", margin:0 });
  });

  // Anaesthetic implications
  s.addShape(pres.shapes.RECTANGLE, { x:5.1, y:1.52, w:4.65, h:0.32, fill:{color:C.para}, line:{color:C.para} });
  s.addText("ANAESTHETIC MANAGEMENT", { x:5.1, y:1.52, w:4.65, h:0.32, fontSize:10, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
  const mgmt = [
    { step:"Pre-op", text:"Autonomic function tests (HUTT, Valsalva, E:I). Assess degree (CASS score). Manage orthostatic hypotension — hydration, stockings" },
    { step:"Induction", text:"Exaggerated hypotension — use reduced doses. Avoid rapid position changes. Pre-load IV fluids. Avoid histamine-releasing drugs" },
    { step:"Intubation", text:"Attenuate SNS response — fentanyl, lignocaine, esmolol. Avoid laryngospasm with adequate depth" },
    { step:"Intraop", text:"Monitor invasive BP (arterial line). Vasopressors ready (phenylephrine, noradrenaline). Avoid tachycardia-inducing agents" },
    { step:"Gastric", text:"Silent gastric regurgitation risk (delayed emptying) → RSI / antacid prophylaxis" },
    { step:"Temp", text:"Impaired thermoregulation — active warming, temperature monitoring" },
    { step:"Emergence", text:"Avoid sudden position change. Monitored discharge; prolonged observation for delayed hypotension" },
    { step:"Post-op", text:"Continue anti-hypotensive precautions. Resume medications. Watch for silent MI (painless ischaemia)" },
  ];
  mgmt.forEach((m, i) => {
    const y = 1.87 + i*0.385;
    s.addShape(pres.shapes.RECTANGLE, { x:5.1, y, w:0.8, h:0.33, fill:{color:C.para}, line:{color:C.para} });
    s.addText(m.step, { x:5.1, y, w:0.8, h:0.33, fontSize:8, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
    s.addShape(pres.shapes.RECTANGLE, { x:5.93, y, w:3.82, h:0.33, fill:{color:i%2===0?"0D2240":"081A36"}, line:{color:C.para, pt:0.4} });
    s.addText(m.text, { x:6.0, y:y+0.05, w:3.7, h:0.22, fontSize:8, color:C.white, margin:0 });
  });
  ftr(s, 14);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 15 — EXAM PEARLS & MNEMONICS
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bgAlt };
  hdr(s, "Exam Pearls & Mnemonics", "High-Yield Points for MD Anaesthesia Theory");

  const pearls = [
    { tag:"MNEMONIC", color:C.bg,     text:"'SLUDS' = Salivation, Lacrimation, Urination, Defecation, Sweating → signs of excess PNS / cholinergic toxicity (organophosphate poisoning)" },
    { tag:"PEARL 1",  color:C.symp,   text:"Sympathetic = Thoracolumbar (T1–L2); Parasympathetic = Craniosacral (CN III,VII,IX,X + S2–S4). Both use ACh at ganglia; SNS uses NE at end-organ" },
    { tag:"PEARL 2",  color:C.para,   text:"Only sympathetic nerve goes to: Adrenal medulla (direct), Sweat glands (ACh!), Pilomotor muscles, Blood vessels in skin" },
    { tag:"PEARL 3",  color:C.teal,   text:"Exception! Sweat glands are innervated by sympathetic fibres but use ACh as neurotransmitter (not NE). Blocked by Atropine, not α/β blockers" },
    { tag:"PEARL 4",  color:C.purple, text:"Dexmedetomidine (α2 agonist) → ↓ NE release from terminals → ↓ HR + BP without respiratory depression. Ideal for awake FOB, ICU, PONV" },
    { tag:"PEARL 5",  color:"E65100", text:"Valsalva ratio ≥ 1.5 = normal PNS (vagal). Cold pressor: BP ↑ ≥ 15/10 mmHg = normal SNS. E:I ratio ≥ 1.21 = normal cardiovagal" },
    { tag:"PEARL 6",  color:C.green,  text:"Composite Autonomic Scoring Scale (CASS 0–10): Mild 1–3, Moderate 4–6, Severe 7–10. Use it to grade autonomic neuropathy pre-operatively" },
    { tag:"PEARL 7",  color:C.symp,   text:"Ketamine → ↑ endogenous NE (indirect sympathomimetic). Propofol → ↓ SNS → vasodilation. Halothane → sensitises heart to catecholamine arrhythmias" },
  ];

  pearls.forEach((p, i) => {
    const y = 1.5 + i*0.505;
    s.addShape(pres.shapes.RECTANGLE, { x:0.25, y, w:1.1, h:0.43, fill:{color:p.color}, line:{color:p.color} });
    s.addText(p.tag, { x:0.25, y, w:1.1, h:0.43, fontSize:8.5, bold:true, color:C.white, align:"center", valign:"middle", margin:0 });
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    s.addText(p.text, { x:1.5, y:y+0.08, w:8.15, h:0.27, fontSize:9, color:C.text, margin:0 });
  });
  ftr(s, 15);
}

// ══════════════════════════════════════════════════════════════
// SLIDE 16 — CLOSING / THANK YOU
// ══════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.bg };
  s.addShape(pres.shapes.OVAL, { x:6.5, y:-1, w:5, h:5, fill:{color:C.symp, transparency:82}, line:{color:C.symp, transparency:82} });
  s.addShape(pres.shapes.OVAL, { x:-1, y:3.5, w:4, h:4, fill:{color:C.para, transparency:82}, line:{color:C.para, transparency:82} });
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  s.addText("THANK YOU", { x:0.82, y:1.15, w:8.5, h:1.0, fontSize:46, bold:true, color:C.white, charSpacing:8, margin:0 });
  s.addText("\"The autonomic nervous system is the silent conductor of life —\nunderstanding it transforms the art of anaesthesia.\"", {
    x:0.82, y:2.25, w:8.5, h:0.9, fontSize:13, italic:true, color:C.silver, margin:0
  });
  s.addText("References:", { x:0.82, y:3.25, w:8, h:0.28, fontSize:10, bold:true, color:C.gold, margin:0 });
  s.addText(
    "• Barash, Cullen & Stoelting's Clinical Anesthesia, 9e — Autonomic Nervous System & Volatile Agents\n" +
    "• Guyton & Hall Textbook of Medical Physiology — Ch. 18: Sympathetic Nervous Control of Circulation\n" +
    "• Adams & Victor's Principles of Neurology, 12e — Autonomic Testing (Ch. 26)\n" +
    "• Histology: A Text & Atlas (Ross & Pawlina) — ANS Divisions\n" +
    "• AAN Guidelines: Clinical Autonomic Testing (Neurology, 1996)",
    { x:0.82, y:3.57, w:8.5, h:1.4, fontSize:8.5, color:C.silver, margin:0 }
  );
  ftr(s, 16);
}

// ── WRITE ──────────────────────────────────────────────────────
pres.writeFile({ fileName: "/home/daytona/workspace/ans-anaesthesia/ANS_Classification_Distribution_Tests_MD.pptx" })
  .then(() => console.log("✅ Done!"))
  .catch(e => { console.error("❌", e); process.exit(1); });