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// ── document content ──────────────────────────────────────────────────────────

const sections = [
  // ── TITLE PAGE ──
  new Paragraph({
    children: [new TextRun({ text: 'General Anaesthesiology', bold: true, size: 52, color: '1F3864' })],
    alignment: AlignmentType.CENTER,
    spacing: { before: 800, after: 200 },
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  new Paragraph({
    children: [new TextRun({ text: 'Class Notes  —  Simplified Study Guide', size: 28, color: '4472C4', italics: true })],
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    spacing: { after: 600 },
  }),
  divider(),

  // ── QUICK OVERVIEW BOX ──
  h1('📋 At a Glance'),
  body('Anaesthesia = making a patient unable to feel pain (and sometimes unconscious) during a procedure.', { bold: true }),
  body('There are three main types:'),
  bullet('General — full unconsciousness (whole body)'),
  bullet('Regional — numbs a large region (e.g. spinal block for leg surgery)'),
  bullet('Local — numbs a tiny area (e.g. dental injection)'),
  body('The choice depends on the patient\'s health, the surgery type, and how long it will take.'),
  divider(),

  // ── SECTION 1 ──
  new Paragraph({ children: [new PageBreak()] }),
  h1('1. Types of Anaesthesia'),

  h2('General Anaesthesia (GA)'),
  body('Puts the patient into a controlled, reversible state of unconsciousness. Think of it as a medically induced deep sleep.'),
  body('It produces four key effects:', { bold: true }),
  bullet('Amnesia — patient won\'t remember the procedure'),
  bullet('Analgesia — complete pain relief'),
  bullet('Muscle paralysis — so surgeons can work safely'),
  bullet('Unconsciousness — patient is unaware throughout'),

  h3('✅ Advantages'),
  bullet('Prevents awareness/recall during surgery'),
  bullet('Allows use of muscle relaxants'),
  bullet('Full control of airway, breathing, and circulation'),
  bullet('Works even if patient is allergic to local anaesthetics'),
  bullet('Can be given quickly; is reversible'),
  bullet('Suitable for long or unpredictable operations'),

  h3('❌ Disadvantages'),
  bullet('Needs careful preoperative preparation'),
  bullet('More expensive and complex than local/regional'),
  bullet('Can cause blood pressure and heart rate fluctuations'),
  body('Common minor side effects:'),
  bullet('Nausea & vomiting', 1),
  bullet('Sore throat', 1),
  bullet('Headache, shivering', 1),
  body('Rare but serious:'),
  bullet('Malignant Hyperthermia — a dangerous, life-threatening fever triggered by certain anaesthetic drugs', 1),
  divider(),

  // ── SECTION 2 ──
  h1('2. Preoperative Management'),
  body('Preoperative period = from the time surgery is scheduled until the patient enters the operating theatre (OT).'),

  h2('A. Preoperative Assessment'),
  h3('History'),
  bullet('Medical history — any new or worsening conditions?'),
  bullet('Previous anaesthetic reactions or complications'),
  bullet('Current medications and known allergies'),
  bullet('Family history (e.g. malignant hyperthermia runs in families)'),
  bullet('Cardiac and lung (pulmonary) status'),

  h3('Physical Examination'),
  bullet('Airway evaluation — the most important part'),
  bullet('Dentition (teeth condition)'),
  bullet('Neck mobility'),
  bullet('Mallampati classification (see below)'),

  h2('B. Airway Evaluation'),
  body('Why it matters: A difficult airway = harder to insert a breathing tube = potentially life-threatening.'),
  body('Red flags for a difficult airway:', { bold: true }),
  bullet('Small or receding jaw'),
  bullet('Limited mouth opening'),
  bullet('Large overbite'),
  bullet('Short or thick neck'),
  bullet('Limited neck extension'),
  bullet('Obesity'),
  bullet('Tumors or trauma in the mouth/throat area'),

  h3('Mallampati Classification'),
  body('A quick bedside test: patient sits, opens mouth wide, sticks out tongue — the anaesthetist scores how much of the throat is visible.'),
  body('Higher score (Class 3-4) = less visible = harder intubation.'),

  h2('C. Preoperative Fasting (NPO = "Nothing by Mouth")'),
  body('Patients must fast before surgery to prevent aspiration (stomach contents entering the lungs during anaesthesia).'),
  new Paragraph({ text: '', spacing: { after: 100 } }),
  simpleTable(
    ['Food / Drink Type', 'Minimum Fasting Time'],
    [
      ['Clear liquids (water, juice without pulp)', '2 hours'],
      ['Breast milk', '4 hours'],
      ['Infant formula', '6 hours'],
      ['Non-human milk', '6 hours'],
      ['Light meal (toast, tea)', '6 hours'],
      ['Full meal (fatty/fried food)', '8 hours'],
    ],
    [5500, 3500]
  ),
  new Paragraph({ text: '', spacing: { after: 160 } }),

  h2('D. Medication Management'),
  body('Not all medications are stopped before surgery:'),
  h3('Continue taking:'),
  bullet('Most regular medications'),
  bullet('Beta-blockers (especially in high-risk cardiac patients)'),
  h3('Hold or adjust:'),
  bullet('Anticoagulants (blood thinners) — bleeding risk'),
  bullet('Oral hypoglycemics e.g. metformin — hypoglycaemia risk'),
  bullet('ACE inhibitors — can cause dangerous BP drop under GA'),
  bullet('MAO inhibitors — dangerous drug interactions'),
  bullet('Herbal supplements (e.g. garlic, ginkgo) — can affect bleeding and drug metabolism'),

  h2('E. Premedication'),
  body('Drugs given before the patient enters the OT, with two main goals: reduce anxiety and prepare the body.'),
  bullet('Midazolam — reduces anxiety (anxiolysis) and causes amnesia so the patient won\'t remember the waiting period'),
  bullet('NSAIDs / Paracetamol — given early to get ahead of pain (preemptive analgesia)'),
  bullet('H2 blockers / antacids — used in patients with acid reflux to reduce aspiration risk'),

  h2('F. ASA Physical Status Classification'),
  body('A standardised scoring system to rate patient fitness before anaesthesia. Higher class = higher risk.'),
  new Paragraph({ text: '', spacing: { after: 100 } }),
  simpleTable(
    ['ASA Class', 'Description', 'Example'],
    [
      ['ASA I', 'Healthy patient', 'Fit adult, no disease'],
      ['ASA II', 'Mild systemic disease', 'Well-controlled hypertension'],
      ['ASA III', 'Severe systemic disease', 'COPD, poorly controlled DM'],
      ['ASA IV', 'Severe disease, constant threat to life', 'Recent MI, severe heart failure'],
      ['ASA V', 'Moribund (not expected to survive without surgery)', 'Ruptured aortic aneurysm'],
      ['ASA VI', 'Brain dead (organ donation)', 'ICU donor patient'],
    ],
    [2000, 3500, 3500]
  ),
  new Paragraph({ text: '', spacing: { after: 160 } }),
  divider(),

  // ── SECTION 3 ──
  new Paragraph({ children: [new PageBreak()] }),
  h1('3. Intraoperative Management'),
  body('Intraoperative = everything that happens while the patient is in the OT during the procedure.'),

  h2('A. Induction of Anaesthesia'),
  body('Induction = making the patient unconscious. This is the most critical phase.'),
  body('Methods:', { bold: true }),
  bullet('IV induction agents — most common in adults (fast and predictable)'),
  bullet('Inhalational agents — more common in children (e.g. sevoflurane via face mask)'),

  body('Typical sequence:', { bold: true }),
  bullet('1. Give IV induction drug (e.g. propofol)'),
  bullet('2. Give an opioid for pain control (e.g. fentanyl)'),
  bullet('3. Give muscle relaxant if needed'),
  bullet('4. Secure the airway (intubation or LMA)'),

  h3('When is Endotracheal Intubation (ETT) needed?'),
  body('ETT = inserting a tube through the mouth into the trachea to protect and control the airway.'),
  bullet('Full stomach (aspiration risk)'),
  bullet('GERD or GI bleeding'),
  bullet('Surgery requires full muscle relaxation'),
  bullet('Surgery on the mouth or face'),
  bullet('Long procedures'),
  bullet('Prone (face down) or lateral (sideways) positioning'),

  h2('B. Maintenance of Anaesthesia'),
  body('After induction, anaesthesia is kept at the right depth throughout surgery.'),
  body('Methods:'),
  bullet('Inhalational agents (most common) — delivered via the breathing circuit'),
  bullet('Total IV Anaesthesia (TIVA) — drug infused continuously via IV'),

  body('Key concept: Anaesthesia depth is a continuum', { bold: true }),
  bullet('Too light → patient may become aware during surgery (very distressing)'),
  bullet('Too deep → dangerous: low blood pressure, slow heart rate'),

  h2('C. Patient Positioning'),
  body('Even lying still on a table can cause injuries if positioning is wrong.'),
  h3('Induction Position'),
  bullet('Sniffing position — head slightly forward, neck extended (like sniffing the air) — opens the airway for intubation'),
  bullet('Obese patients: ramped at 30° — same goal'),
  tip('Goal:', 'Align the external ear canal (tragus) with the sternum.'),

  h3('Positioning Hazards'),
  bullet('Ocular injuries — corneal abrasion if eyes not taped shut'),
  bullet('Nerve injuries:'),
  bullet('Ulnar nerve (elbow area)', 1),
  bullet('Common peroneal nerve (knee area)', 1),
  bullet('Brachial plexus (shoulder/arm)', 1),
  body('Prevention rules:', { bold: true }),
  bullet('Never abduct arms beyond 90°'),
  bullet('Pad all pressure points'),
  bullet('Avoid extreme neck flexion or extension'),

  h2('D. Intraoperative Monitoring (Minimum Requirements)'),
  body('The anaesthetist continuously monitors the patient throughout surgery:'),
  new Paragraph({ text: '', spacing: { after: 100 } }),
  simpleTable(
    ['Monitor', 'What it checks'],
    [
      ['ECG', 'Heart rhythm and rate'],
      ['Blood pressure (every 5 min)', 'Cardiovascular stability'],
      ['Pulse oximetry (SpO₂)', 'Oxygen saturation in blood'],
      ['Capnography (EtCO₂)', 'CO₂ in exhaled breath — confirms correct tube placement'],
      ['Temperature', 'Prevents hypothermia or malignant hyperthermia'],
      ['Inspired/expired gas concentrations', 'Anaesthetic agent levels'],
      ['Oxygen supply', 'Ensures patient gets enough oxygen'],
    ],
    [3500, 5500]
  ),
  new Paragraph({ text: '', spacing: { after: 160 } }),
  body('Always available in OT: suction, defibrillator, emergency drugs, dantrolene (for malignant hyperthermia).'),
  divider(),

  // ── SECTION 4 ──
  new Paragraph({ children: [new PageBreak()] }),
  h1('4. Anaesthetic Drugs & How They Work'),

  h2('1. Induction Agents'),
  h3('Propofol (the most common)'),
  body('What it looks like: a white milky liquid (nicknamed "milk of amnesia").'),
  body('How it works (MOA):'),
  bullet('Potentiates (strengthens) GABA-A receptors'),
  bullet('GABA = the brain\'s main inhibitory (calming) neurotransmitter'),
  bullet('More GABA activity → more chloride ions enter neurons → neurons become hyperpolarised (harder to fire)'),
  bullet('Result: hypnosis and sedation'),
  body('Advantages:', { bold: true }),
  bullet('Very rapid onset (seconds)'),
  bullet('Rapid, clean recovery'),
  bullet('Less nausea/vomiting than other agents'),
  body('Disadvantages:', { bold: true }),
  bullet('Pain on injection (stings going in)'),
  bullet('Can cause hypotension (low BP) — watch out'),

  h2('2. Inhalational Agents'),
  body('Examples: Sevoflurane, Desflurane, Nitrous oxide (N₂O)'),
  body('How they work (MOA):'),
  bullet('Enhance GABA-mediated inhibition (same pathway as propofol, but via gases)'),
  bullet('Block NMDA receptors → decrease excitatory brain activity'),
  bullet('Depress CNS activity overall'),
  body('Result: loss of consciousness, amnesia, and some degree of muscle relaxation.'),

  h2('3. Opioids'),
  body('Examples: Morphine, Fentanyl, Sufentanil, Remifentanil'),
  body('Opioids are the backbone of intraoperative pain management.'),
  body('How they work (MOA):'),
  bullet('Bind to Mu (μ) opioid receptors in the brain and spinal cord'),
  bullet('Inhibit adenylate cyclase → less cAMP → neurons less excitable'),
  bullet('Decrease calcium influx into nerve terminals'),
  bullet('Reduce neurotransmitter release → block pain signals reaching the brain'),
  body('Effects:', { bold: true }),
  bullet('Analgesia (pain relief)'),
  bullet('Sedation'),
  bullet('Respiratory depression (the main dangerous side effect — slows breathing)'),

  h2('4. Muscle Relaxants'),
  h3('A. Succinylcholine — Depolarising'),
  body('Fast-acting, short-lasting. Used when you need very rapid intubation (e.g. full-stomach emergency).'),
  body('How it works (MOA):'),
  bullet('Binds to nicotinic acetylcholine receptors at the neuromuscular junction'),
  bullet('Causes persistent depolarisation (the muscle "fires" briefly → you see fasciculations — brief muscle twitches)'),
  bullet('The receptor stays activated → cannot repolarise → flaccid paralysis'),
  tip('Key feature:', 'Rapid onset (~60 sec), short duration (~10 min). No reversal agent needed — it wears off on its own.'),

  h3('B. Non-depolarising Muscle Relaxants'),
  body('Examples: Rocuronium, Vecuronium, Atracurium'),
  body('How they work (MOA):'),
  bullet('Competitive antagonists — they compete with acetylcholine for the nicotinic receptor'),
  bullet('Block acetylcholine from binding → no depolarisation → flaccid paralysis'),
  body('Duration: 30-60 minutes.'),
  body('Reversal:'),
  bullet('Sugammadex — encapsulates (wraps around) the drug molecule and inactivates it — very effective reversal'),
  divider(),

  // ── SECTION 5 ──
  h1('5. Postoperative Management'),
  body('After surgery, the patient goes to the Post-Anaesthesia Care Unit (PACU) — also called the recovery room.'),
  body('Critical patients may go directly to the ICU.'),

  h2('PACU Discharge: Modified Aldrete Score'),
  body('Scored on 5 criteria (0-2 each, max 10). Patient needs ≥9 to be discharged from PACU.'),
  new Paragraph({ text: '', spacing: { after: 100 } }),
  simpleTable(
    ['Criterion', 'What\'s assessed'],
    [
      ['Activity', 'Can the patient move limbs on command?'],
      ['Circulation', 'Blood pressure within 20% of baseline?'],
      ['Consciousness', 'Is the patient fully awake and oriented?'],
      ['Oxygen Saturation (SpO₂)', 'Is SpO₂ ≥92% on room air?'],
      ['Respiration', 'Is breathing adequate, no respiratory distress?'],
    ],
    [3500, 5500]
  ),
  new Paragraph({ text: '', spacing: { after: 160 } }),

  h2('Phase 2 Discharge (Going Home)'),
  body('Before a patient can be discharged home, ALL of these must be met:'),
  bullet('Vital signs stable'),
  bullet('Pain is controlled (oral analgesia is adequate)'),
  bullet('Normal temperature (normothermia)'),
  bullet('No nausea or vomiting'),
  bullet('Able to walk (if applicable)'),
  bullet('Surgical site is intact and stable'),
  divider(),

  // ── QUICK REFERENCE CARD ──
  new Paragraph({ children: [new PageBreak()] }),
  h1('📚 Quick Reference Summary'),

  new Paragraph({
    children: [new TextRun({ text: 'Key Drug Mechanisms at a Glance', bold: true, size: 26, color: '1F3864' })],
    spacing: { before: 200, after: 120 },
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  simpleTable(
    ['Drug / Class', 'Receptor / Target', 'Key Effect'],
    [
      ['Propofol', 'GABA-A receptor (↑ Cl⁻ influx)', 'Hypnosis, sedation'],
      ['Sevoflurane / Desflurane', 'GABA-A + NMDA block', 'Unconsciousness, amnesia'],
      ['Opioids (Fentanyl, Morphine)', 'Mu (μ) opioid receptor', 'Analgesia, respiratory depression'],
      ['Succinylcholine', 'Nicotinic receptor (persistent depol.)', 'Rapid paralysis, short duration'],
      ['Rocuronium (non-depol.)', 'Nicotinic receptor (competitive block)', 'Flaccid paralysis, 30-60 min'],
    ],
    [2800, 3600, 2600]
  ),
  new Paragraph({ text: '', spacing: { after: 200 } }),

  new Paragraph({
    children: [new TextRun({ text: 'Common Mnemonics', bold: true, size: 26, color: '1F3864' })],
    spacing: { before: 200, after: 120 },
  }),
  tip('GA effects:', 'Amnesia · Analgesia · Areflexia (muscle paralysis) · Areactivity (unconsciousness) — "The 4 As"'),
  tip('Fasting rule:', '"2-4-6-8" — Liquids 2h, Breast milk 4h, Formula/light meal 6h, Full meal 8h'),
  tip('Mallampati:', 'Class I = easy · Class IV = expect trouble'),
  tip('ASA score:', 'I = fit · II = mild disease · III = severe · IV = life-threatening · V = moribund · VI = brain dead'),

  new Paragraph({ text: '', spacing: { after: 200 } }),
  divider(),
  new Paragraph({
    children: [new TextRun({ text: 'Based on Class 1 — General Anaesthesiology lecture notes', italics: true, size: 18, color: '888888' })],
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