const {
  Document, Packer, Paragraph, TextRun, Table, TableRow, TableCell,
  AlignmentType, HeadingLevel, BorderStyle, WidthType, ShadingType,
  PageNumber, Header, Footer, TabStopType, TabStopPosition,
  UnderlineType
} = require('docx');
const fs = require('fs');

// ─── HELPERS ────────────────────────────────────────────────────────────────
const HR = () => new Paragraph({
  border: { bottom: { style: BorderStyle.SINGLE, size: 6, color: "2E4057" } },
  spacing: { before: 100, after: 100 }
});

const heading1 = (text) => new Paragraph({
  children: [new TextRun({ text, bold: true, size: 28, color: "1A3A5C", font: "Calibri" })],
  heading: HeadingLevel.HEADING_1,
  spacing: { before: 320, after: 120 },
  border: {
    bottom: { style: BorderStyle.SINGLE, size: 4, color: "1A3A5C" }
  }
});

const heading2 = (text) => new Paragraph({
  children: [new TextRun({ text, bold: true, size: 24, color: "2E4057", font: "Calibri" })],
  heading: HeadingLevel.HEADING_2,
  spacing: { before: 240, after: 80 }
});

const heading3 = (text) => new Paragraph({
  children: [new TextRun({ text, bold: true, italics: true, size: 22, color: "4A6741", font: "Calibri" })],
  spacing: { before: 180, after: 60 }
});

const body = (text) => new Paragraph({
  children: [new TextRun({ text, size: 22, font: "Calibri" })],
  spacing: { after: 60 },
  indent: { left: 0 }
});

const bullet = (text, bold = false) => new Paragraph({
  children: [new TextRun({ text, size: 22, bold, font: "Calibri" })],
  bullet: { level: 0 },
  spacing: { after: 40 }
});

const subbullet = (text) => new Paragraph({
  children: [new TextRun({ text, size: 21, font: "Calibri" })],
  bullet: { level: 1 },
  spacing: { after: 30 }
});

const bold_body = (label, text) => new Paragraph({
  children: [
    new TextRun({ text: label + ": ", bold: true, size: 22, font: "Calibri", color: "1A3A5C" }),
    new TextRun({ text, size: 22, font: "Calibri" })
  ],
  spacing: { after: 60 }
});

const noteBox = (text) => new Paragraph({
  children: [new TextRun({ text: "  Key Point: " + text, size: 21, italics: true, font: "Calibri", color: "555555" })],
  shading: { type: ShadingType.CLEAR, fill: "EBF5FB" },
  spacing: { before: 60, after: 60 },
  indent: { left: 240 }
});

const spacer = () => new Paragraph({ text: "", spacing: { after: 80 } });

// ─── TWO-COLUMN TABLE ────────────────────────────────────────────────────────
const twoColTable = (rows, col1Width = 40, col2Width = 60) => {
  const tableRows = rows.map(([c1, c2]) => new TableRow({
    children: [
      new TableCell({
        width: { size: col1Width, type: WidthType.PERCENTAGE },
        children: [new Paragraph({ children: [new TextRun({ text: c1, bold: c1.endsWith(':') || rows[0][0] === c1, size: 21, font: "Calibri" })], spacing: { after: 40 } })],
        shading: { type: ShadingType.CLEAR, fill: c1 === rows[0][0] ? "D6EAF8" : "FFFFFF" }
      }),
      new TableCell({
        width: { size: col2Width, type: WidthType.PERCENTAGE },
        children: [new Paragraph({ children: [new TextRun({ text: c2, size: 21, font: "Calibri" })], spacing: { after: 40 } })]
      })
    ]
  }));
  return new Table({
    width: { size: 100, type: WidthType.PERCENTAGE },
    rows: tableRows,
    margins: { top: 60, bottom: 60, left: 120, right: 120 }
  });
};

// ─── TITLE PAGE CONTENT ──────────────────────────────────────────────────────
const titleSection = [
  new Paragraph({
    children: [new TextRun({ text: "SMT N H L M M C", bold: true, size: 32, font: "Calibri", color: "1A3A5C" })],
    alignment: AlignmentType.CENTER,
    spacing: { before: 400, after: 80 }
  }),
  new Paragraph({
    children: [new TextRun({ text: "General Medicine – May 2026", bold: true, size: 28, font: "Calibri", color: "2E4057" })],
    alignment: AlignmentType.CENTER,
    spacing: { after: 80 }
  }),
  new Paragraph({
    children: [new TextRun({ text: "R2 Examination  |  Duration: 3 Hours  |  Total Marks: 100", size: 24, font: "Calibri", color: "555555" })],
    alignment: AlignmentType.CENTER,
    spacing: { after: 80 }
  }),
  new Paragraph({
    children: [new TextRun({ text: "MODEL ANSWER SHEET", bold: true, size: 36, font: "Calibri", color: "1A3A5C", underline: { type: UnderlineType.SINGLE } })],
    alignment: AlignmentType.CENTER,
    spacing: { before: 200, after: 400 }
  }),
  HR(),
  spacer()
];

// ═══════════════════════════════════════════════════════════════════════════════
// Q1 – UTI (20 marks)
// ═══════════════════════════════════════════════════════════════════════════════
const q1 = [
  heading1("Q.1  Evaluate and Manage a Patient Admitted with Urinary Tract Infection  [20 Marks]"),

  heading2("Introduction"),
  body("A urinary tract infection (UTI) is a microbial invasion of the normally sterile urinary tract. It encompasses a spectrum from asymptomatic bacteriuria to life-threatening urosepsis. Prompt evaluation and targeted management are essential to prevent complications including acute kidney injury, septicaemia, and chronic pyelonephritis."),

  heading2("A. Definition & Classification"),
  twoColTable([
    ["Type", "Definition"],
    ["Uncomplicated UTI", "Lower tract infection (cystitis/urethritis) in a healthy, non-pregnant woman with a normal urinary tract"],
    ["Complicated UTI", "Infection associated with structural/functional abnormality, male sex, pregnancy, immunocompromise, DM, renal failure, or hospitalisation"],
    ["Lower UTI (Cystitis)", "Infection confined to the bladder – dysuria, frequency, urgency, suprapubic pain"],
    ["Upper UTI (Pyelonephritis)", "Infection involving the kidney – fever, rigors, loin pain, CVAT, systemic upset"],
    ["Asymptomatic Bacteriuria", "≥10⁵ CFU/mL on two consecutive cultures in an asymptomatic patient"],
    ["Catheter-Associated UTI", "UTI in a patient with a urinary catheter in situ for >48 hours"],
    ["Recurrent UTI", "≥2 symptomatic episodes in 6 months or ≥3 in 12 months"],
  ]),
  spacer(),

  heading2("B. Etiology"),
  heading3("Common Causative Organisms"),
  twoColTable([
    ["Organism", "Notes"],
    ["E. coli (75–85%)", "Most common; fimbriae mediate uroepithelial adhesion"],
    ["Klebsiella pneumoniae", "Especially in hospitalised/diabetic patients"],
    ["Staphylococcus saprophyticus", "Young sexually active women"],
    ["Proteus mirabilis", "Urease-producing; alkaline urine, struvite stones"],
    ["Enterococcus faecalis", "Nosocomial; often catheter-associated"],
    ["Pseudomonas aeruginosa", "Complicated/nosocomial UTI; MDR"],
  ]),

  heading3("Risk Factors"),
  bullet("Female sex (short urethra, proximity to anus)"),
  bullet("Sexual activity, diaphragm/spermicide use"),
  bullet("Diabetes mellitus (glycosuria promotes bacterial growth)"),
  bullet("Urinary tract obstruction: BPH, calculi, stricture, tumour"),
  bullet("Vesicoureteral reflux (VUR), neurogenic bladder"),
  bullet("Immunosuppression, pregnancy, catheterisation"),
  bullet("Post-menopausal state (reduced oestrogen, altered vaginal flora)"),
  spacer(),

  heading2("C. Clinical Evaluation"),
  heading3("1. History"),
  bullet("Chief complaints: dysuria, frequency, urgency, nocturia, haematuria, foul-smelling urine, suprapubic pain"),
  bullet("Systemic features: fever, chills, rigors, loin/flank pain, nausea, vomiting (suggestive of upper UTI/pyelonephritis)"),
  bullet("Relevant history: previous UTIs, urological procedures, catheterisation, sexual history, diabetes, immunosuppression"),
  bullet("Drug history: recent antibiotics (risk of resistant organisms), NSAIDs"),
  bullet("Obstetric history in women: pregnancy, LMP"),

  heading3("2. Physical Examination"),
  bullet("General: fever, tachycardia, hypotension (signs of sepsis)"),
  bullet("Abdominal examination: suprapubic tenderness (cystitis)"),
  bullet("Renal examination: costovertebral angle tenderness (CVAT) – positive in pyelonephritis"),
  bullet("Genital examination: urethral discharge, vaginitis, prostate tenderness/enlargement in men"),
  bullet("Signs of complications: confusion (urosepsis), peripheral oedema (nephrotic)"),
  spacer(),

  heading2("D. Investigations"),
  heading3("1. Urine Examination"),
  bullet("Urine dipstick: leucocyte esterase (+ = pyuria), nitrites (+ = gram-negative bacteria), blood, protein"),
  bullet("Urine microscopy: >5 WBC/HPF = pyuria; bacteriuria; casts in pyelonephritis"),
  bullet("Urine culture and sensitivity (midstream clean catch): gold standard; ≥10⁵ CFU/mL diagnostic; guides antibiotic choice"),
  bullet("Urine pregnancy test in women of childbearing age"),

  heading3("2. Blood Investigations"),
  bullet("CBC: leukocytosis with neutrophilia (infection/sepsis), anaemia (chronic)"),
  bullet("Blood cultures: two sets before antibiotics if sepsis/pyelonephritis suspected"),
  bullet("Renal function tests (BUN, creatinine, electrolytes): assess AKI"),
  bullet("Blood glucose: screen for diabetes"),
  bullet("CRP / Procalcitonin: markers of systemic infection severity"),
  bullet("LFTs if patient jaundiced or severe sepsis"),

  heading3("3. Imaging"),
  bullet("Ultrasound (KUB): first-line; detects hydronephrosis, abscess, calculi, bladder pathology"),
  bullet("CT abdomen/pelvis (non-contrast or contrast): gold standard for complicated UTI, renal/perirenal abscess, calculi"),
  bullet("VCUG (voiding cystourethrogram): if VUR suspected (children, recurrent UTI)"),
  bullet("Cystoscopy: if haematuria persists or bladder pathology suspected"),
  spacer(),

  heading2("E. Management"),
  heading3("1. General Measures"),
  bullet("Adequate hydration: IV fluids if unable to tolerate orally or sepsis"),
  bullet("Analgesia: paracetamol or NSAIDs for pain/fever (avoid NSAIDs if AKI)"),
  bullet("Catheter removal if catheter-associated UTI; re-site only if necessary"),
  bullet("Control of underlying precipitating factors (glycaemic control in DM, relieve obstruction)"),

  heading3("2. Antibiotic Therapy"),
  body("Choice is guided by culture results, local resistance patterns, severity, and patient factors. Start empirical therapy; narrow down after culture sensitivity results."),
  spacer(),
  twoColTable([
    ["Condition", "First-line Empirical Antibiotic"],
    ["Uncomplicated Cystitis (women)", "Nitrofurantoin 100 mg BD x 5 days OR Trimethoprim 200 mg BD x 7 days OR Fosfomycin 3g single dose"],
    ["Complicated Cystitis", "Co-amoxiclav OR Ciprofloxacin 500 mg BD x 7 days (guided by culture)"],
    ["Acute Uncomplicated Pyelonephritis (oral)", "Ciprofloxacin 500 mg BD x 7–10 days OR Co-trimoxazole x 14 days"],
    ["Pyelonephritis requiring admission", "IV Ceftriaxone 1g OD OR IV Ciprofloxacin 400 mg BD → step down to oral when afebrile 48 hrs"],
    ["Urosepsis", "IV Piperacillin-tazobactam 4.5g TDS OR IV Meropenem 1g TDS (if MDR suspected); add gentamicin if severe"],
    ["Pregnant Women", "Cefalexin or Amoxicillin-clavulanate (nitrofurantoin avoided in 3rd trimester; fluoroquinolones contraindicated)"],
    ["Asymptomatic Bacteriuria", "Treat only if pregnant, pre-urological procedure, or immunocompromised"],
  ]),
  spacer(),

  heading3("3. Management of Complications"),
  bullet("Renal/perirenal abscess: IV antibiotics + CT-guided percutaneous drainage if >3 cm"),
  bullet("Emphysematous pyelonephritis: IV antibiotics + urgent nephrostomy/nephrectomy in severe cases"),
  bullet("Urosepsis: follow sepsis bundle – IV fluids, broad-spectrum antibiotics within 1 hr, source control, vasopressors if refractory"),
  bullet("Obstruction: emergency decompression (ureteric stent or nephrostomy) before definitive management"),
  spacer(),

  heading3("4. Follow-up & Prevention"),
  bullet("Test of cure urine culture: 1–2 weeks post-treatment in pregnant women, complicated UTI, pyelonephritis"),
  bullet("Long-term low-dose prophylaxis (trimethoprim 100 mg nocte OR nitrofurantoin 50 mg nocte) for recurrent UTI"),
  bullet("Post-coital single-dose antibiotic for coitally-related recurrence"),
  bullet("Lifestyle advice: adequate fluid intake, voiding after intercourse, avoid spermicide, wipe front to back"),
  bullet("Cranberry products: modest evidence in premenopausal women; not first-line"),
  noteBox("Treat and investigate the underlying cause of complicated UTI to prevent recurrence and renal damage."),
  spacer()
];

// ═══════════════════════════════════════════════════════════════════════════════
// Q2 – Acute Abdominal Pain in 16-yr-old Girl, Sibling is Diabetic (20 marks)
// ═══════════════════════════════════════════════════════════════════════════════
const q2 = [
  heading1("Q.2  Acute Abdominal Pain in a 16-Year-Old Girl (Sibling Diabetic)  [20 Marks]"),

  heading2("Introduction"),
  body("A 16-year-old girl presenting to casualty with acute abdominal pain, whose 27-year-old sibling has diabetes, warrants a broad differential. Given the familial predisposition to Type 1 Diabetes Mellitus (T1DM), the most critical diagnosis to exclude is Diabetic Ketoacidosis (DKA), which classically presents with abdominal pain. However, a thorough evaluation must cover all possible etiologies."),

  heading2("A. Differential Diagnosis"),
  heading3("High Priority (Must Exclude)"),
  bullet("Diabetic Ketoacidosis (DKA) – in an undiagnosed or known T1DM patient"),
  bullet("Appendicitis – most common surgical emergency in this age group"),
  bullet("Ectopic pregnancy – must exclude in any adolescent female"),
  bullet("Ovarian torsion / Ruptured ovarian cyst"),
  bullet("Pelvic Inflammatory Disease (PID)"),

  heading3("Other Differentials"),
  bullet("Mesenteric lymphadenitis"),
  bullet("Intestinal obstruction (adhesions, volvulus, intussusception)"),
  bullet("Urinary tract infection / Renal colic"),
  bullet("Peptic ulcer disease / Gastritis"),
  bullet("Acute pancreatitis"),
  bullet("Inflammatory bowel disease (Crohn's / Ulcerative colitis)"),
  bullet("Mittelschmerz (mid-cycle pain)"),
  bullet("Dysmenorrhoea"),
  bullet("Hepatitis / Cholecystitis"),
  spacer(),

  heading2("B. Evaluation"),
  heading3("1. History"),
  bullet("Pain: onset (sudden vs. gradual), character (colicky, constant, burning), site, radiation, duration, severity (VAS 0–10)"),
  bullet("Associated symptoms: nausea, vomiting, fever, diarrhoea/constipation, anorexia"),
  bullet("Genitourinary: dysuria, frequency, vaginal discharge, LMP, sexual activity"),
  bullet("Menstrual history: regular cycles, LMP, possibility of pregnancy"),
  bullet("Diabetic symptoms: polyuria, polydipsia, weight loss, polyphagia – screen for T1DM given family history"),
  bullet("Systemic: fever, weight loss, fatigue, joint pains (IBD)"),
  bullet("Drug/medication history, allergies"),
  bullet("Family history: T1DM in sibling – increased risk for T1DM in the patient"),

  heading3("2. Physical Examination"),
  bullet("Vitals: temperature, BP, pulse, respiratory rate, SpO₂, GCS"),
  bullet("General: dehydration, weight, Kussmaul breathing (deep, rapid – DKA), fruity breath (DKA), pallor, jaundice"),
  bullet("Abdominal exam: site of tenderness, guarding, rigidity, rebound, bowel sounds, Murphy's sign"),
  subbullet("RIF tenderness + Rovsing sign + Psoas sign → Appendicitis"),
  subbullet("Adnexal tenderness + cervical excitation → PID / Ectopic"),
  subbullet("Diffuse tenderness in DKA"),
  bullet("Pelvic examination (if appropriate age, with consent): cervical os, discharge, adnexal masses"),
  bullet("Respiratory: Kussmaul breathing pattern in DKA"),
  spacer(),

  heading2("C. Investigations"),
  heading3("Immediate (Bedside / Urgent)"),
  bullet("Blood glucose: if >11 mmol/L (200 mg/dL) → screen for DKA"),
  bullet("Urine pregnancy test (βhCG): mandatory in all females of reproductive age with abdominal pain"),
  bullet("Urine dipstick: ketonuria + glycosuria (DKA), haematuria (renal colic/UTI), nitrites (UTI)"),
  bullet("ECG if suspecting electrolyte imbalance (DKA → hypokalaemia → arrhythmia)"),

  heading3("Blood Investigations"),
  bullet("CBP / CBC: leukocytosis (infection/appendicitis), anaemia"),
  bullet("Blood glucose (formal serum): hyperglycaemia (DKA >11 mmol/L)"),
  bullet("ABG/VBG: metabolic acidosis (pH <7.3, HCO₃ <15, high anion gap) in DKA"),
  bullet("Serum electrolytes (Na, K, Cl, HCO₃): critical in DKA; hypokalaemia after insulin therapy"),
  bullet("Anion gap: = Na – (Cl + HCO₃); >12 suggests high-anion-gap metabolic acidosis"),
  bullet("Serum ketones (beta-hydroxybutyrate >3 mmol/L confirms DKA)"),
  bullet("Renal function (BUN, creatinine): dehydration/AKI in DKA"),
  bullet("Serum amylase/lipase: if pancreatitis suspected"),
  bullet("Serum βhCG (quantitative): if urine βhCG positive → serial monitoring"),
  bullet("LFTs: hepatitis, cholecystitis"),
  bullet("CRP, ESR: inflammation markers"),
  bullet("HbA1c: if DM suspected; elevated suggests prolonged hyperglycaemia"),
  bullet("Thyroid function tests, autoantibodies (anti-GAD, anti-islet) if new T1DM suspected"),

  heading3("Imaging"),
  bullet("USG abdomen + pelvis (first-line): appendix, ovaries, uterus, free fluid"),
  bullet("Transvaginal ultrasound: if ectopic pregnancy suspected (βhCG positive)"),
  bullet("CT abdomen/pelvis (with contrast): if USG inconclusive, appendicitis, obstruction"),
  bullet("X-ray abdomen (erect): if obstruction/perforation suspected – free air under diaphragm"),
  spacer(),

  heading2("D. Most Likely Diagnosis: Diabetic Ketoacidosis (DKA)"),
  body("Given that the sibling is a T1DM patient (diagnosed at ~11 years), the patient is at approximately 6-fold higher risk of T1DM. DKA can be the presenting manifestation in 25–40% of new T1DM patients and is a recognised cause of acute abdominal pain."),

  heading3("DKA Diagnostic Criteria (DKA Triad)"),
  twoColTable([
    ["Parameter", "Threshold for DKA"],
    ["Blood glucose", ">11 mmol/L (200 mg/dL) or known diabetes"],
    ["Ketonaemia", "≥3 mmol/L (or urine ketones ≥2+ on dipstick)"],
    ["Metabolic acidosis", "pH <7.3 and/or HCO₃ <15 mmol/L"],
  ]),
  spacer(),

  heading3("DKA Management (5-Pronged Approach)"),
  bullet("1. IV Fluid Resuscitation", true),
  subbullet("0.9% NaCl: 1L over 1st hour → 1L over 2nd hour → 1L over next 2 hrs → reassess"),
  subbullet("Switch to 0.45% NaCl if corrected Na >135 mmol/L"),
  subbullet("Add 10% dextrose when blood glucose falls to 10–14 mmol/L to prevent hypoglycaemia"),
  bullet("2. Insulin Therapy", true),
  subbullet("Fixed rate IV insulin infusion (FRIII): 0.1 units/kg/hour (e.g. Actrapid in 0.9% NaCl)"),
  subbullet("Do NOT start insulin until serum K+ ≥3.5 mmol/L"),
  subbullet("Continue FRIII until ketones <0.3 mmol/L, pH >7.3, HCO₃ >18"),
  bullet("3. Potassium Replacement", true),
  subbullet("K+ 3.5–5.5 mmol/L: add 40 mmol KCl/L to IVF"),
  subbullet("K+ <3.5 mmol/L: withhold insulin, replace K+ aggressively before starting insulin"),
  subbullet("K+ >5.5 mmol/L: no KCl, recheck hourly"),
  bullet("4. Monitoring", true),
  subbullet("Hourly capillary ketones and glucose until ketones <0.3 mmol/L"),
  subbullet("2-hourly ABG/VBG for pH and bicarbonate"),
  subbullet("Continuous cardiac monitoring – ECG for arrhythmias (hypokalaemia)"),
  subbullet("Fluid balance chart hourly, urine output monitoring"),
  subbullet("Electrolytes 2-hourly for first 6 hours"),
  bullet("5. Treat Precipitating Cause", true),
  subbullet("Infection (most common precipitant): empiric antibiotics if infective focus identified"),
  subbullet("Missed insulin, stress, illness"),
  bullet("Bicarbonate: consider only if pH <6.9 (severe acidosis); not routine"),
  bullet("Nasogastric tube: if reduced consciousness or vomiting to prevent aspiration"),
  bullet("Foley catheter: if unable to pass urine or accurate fluid monitoring needed"),
  bullet("Transition to SC insulin: once DKA resolved + patient eating → start basal-bolus regimen"),
  noteBox("Always treat the patient's abdominal pain as genuine. DKA-related abdominal pain resolves with DKA treatment; persistent pain after DKA resolves suggests a separate surgical cause."),
  spacer()
];

// ═══════════════════════════════════════════════════════════════════════════════
// Q3 – Hypertension (20 marks)
// ═══════════════════════════════════════════════════════════════════════════════
const q3 = [
  heading1("Q.3  Hypertension: Definition, Classification, Evaluation and Management  [20 Marks]"),

  heading2("A. Definition"),
  body("Hypertension (HTN) is defined as a persistently elevated blood pressure (BP) of ≥140 mmHg systolic and/or ≥90 mmHg diastolic, measured on at least two separate occasions (WHO/JNC-8/ESC definition). The 2017 ACC/AHA guideline lowered the threshold to ≥130/80 mmHg."),
  noteBox("A single elevated reading does not constitute hypertension. Diagnosis requires persistent elevation on ≥2 visits unless hypertensive emergency."),

  heading2("B. Classification"),
  heading3("JNC-8 / WHO Classification"),
  twoColTable([
    ["Category", "Systolic (mmHg)", "Diastolic (mmHg)"],
    ["Normal", "<120", "<80"],
    ["Elevated (Pre-HTN)", "120–129", "<80"],
    ["Stage 1 HTN", "130–139", "80–89"],
    ["Stage 2 HTN", "≥140", "≥90"],
    ["Hypertensive Urgency", "≥180", "≥120 (no end-organ damage)"],
    ["Hypertensive Emergency", "≥180", "≥120 (with end-organ damage)"],
  ]),

  spacer(),
  heading3("By Etiology"),
  bullet("Primary (Essential) Hypertension – 90–95%: no identifiable cause; polygenic, multifactorial; related to age, obesity, diet, genetics"),
  bullet("Secondary Hypertension – 5–10%: identifiable cause; should be suspected in young patients, resistant HTN, or sudden onset"),
  twoColTable([
    ["Cause", "Examples"],
    ["Renal parenchymal", "CKD, glomerulonephritis, polycystic kidney disease"],
    ["Renovascular", "Renal artery stenosis (atherosclerosis, fibromuscular dysplasia)"],
    ["Endocrine", "Primary hyperaldosteronism (Conn's syndrome), Cushing's syndrome, Phaeochromocytoma, Hyperthyroidism, Acromegaly"],
    ["Obstructive sleep apnoea", "Intermittent hypoxia → sympathetic activation"],
    ["Drugs/Substances", "OCP, NSAIDs, steroids, sympathomimetics, cocaine, liquorice"],
    ["Coarctation of aorta", "Young patient, absent femoral pulses, rib notching on CXR"],
  ]),

  spacer(),
  heading3("Special Types"),
  bullet("Isolated systolic HTN: SBP ≥140, DBP <90 – common in elderly (reduced arterial compliance)"),
  bullet("White coat HTN: elevated in clinic, normal ambulatory readings"),
  bullet("Masked HTN: normal in clinic, elevated on ABPM"),
  bullet("Resistant HTN: BP ≥140/90 despite ≥3 antihypertensive drugs at optimal doses (including a diuretic)"),
  spacer(),

  heading2("C. Evaluation / Workup"),
  heading3("1. History"),
  bullet("Duration, severity of HTN, previous BP readings"),
  bullet("Symptoms: headache, visual disturbance, chest pain, palpitations, SOB, oedema"),
  bullet("End-organ damage symptoms: chest pain (MI/angina), stroke (neurological deficit), visual loss, renal symptoms"),
  bullet("Risk factor assessment: smoking, DM, dyslipidaemia, family history, obesity, diet, physical activity, alcohol, stress"),
  bullet("Drug history: OCP, NSAIDs, decongestants, steroids, herbal remedies"),
  bullet("Secondary causes: flushing/headache/palpitations (phaeochromocytoma), weight gain/striae (Cushing's), nocturia/hypokalaemia (Conn's)"),

  heading3("2. Physical Examination"),
  bullet("Correct BP measurement: seated, arm at heart level, 2 readings 1–2 min apart, bilateral arms, standing BP (postural drop)"),
  bullet("BMI, waist circumference"),
  bullet("Fundoscopy: Keith-Wagener classification of hypertensive retinopathy (Grade I–IV)"),
  bullet("Cardiovascular: JVP, apex beat (displaced = LVH), S4 gallop, murmurs, peripheral pulses"),
  bullet("Neurological: focal deficits (stroke/TIA)"),
  bullet("Renal: bruits over renal arteries (renovascular HTN), palpable kidneys (PKD)"),
  bullet("Endocrine signs: moon face, buffalo hump (Cushing's), goitre (thyroid), abdominal striae"),
  spacer(),

  heading3("3. Investigations"),
  body("Aimed at: (a) confirming HTN, (b) assessing cardiovascular risk, (c) identifying end-organ damage, (d) excluding secondary causes."),
  twoColTable([
    ["Investigation", "Purpose"],
    ["Urinalysis + urine ACR", "Proteinuria, haematuria (renal parenchymal disease, end-organ damage)"],
    ["Serum electrolytes (Na, K)", "Hypokalaemia in Conn's syndrome; hyponatraemia"],
    ["Renal function (eGFR, creatinine)", "CKD as cause and consequence of HTN"],
    ["Fasting blood glucose / HbA1c", "DM as cardiovascular risk factor"],
    ["Fasting lipid profile", "Dyslipidaemia – calculate 10-yr CVD risk (QRISK)"],
    ["Full blood count", "Anaemia, polycythaemia"],
    ["ECG (12-lead)", "LVH (Sokolow-Lyon criteria), arrhythmias, ischaemia"],
    ["Echocardiogram", "LVH, diastolic dysfunction, EF – if ECG suggestive or cardiac symptoms"],
    ["Renal USS", "Renal size (PKD, chronic renal parenchymal disease)"],
    ["Ambulatory BP monitoring (ABPM)", "Confirm diagnosis, white coat/masked HTN, dipping status"],
    ["Serum cortisol/dexamethasone suppression test", "If Cushing's suspected"],
    ["Plasma aldosterone:renin ratio", "If Conn's syndrome suspected (hypokalaemia, resistant HTN)"],
    ["24-hr urine metanephrines / plasma metanephrines", "If phaeochromocytoma suspected"],
    ["Renal artery Doppler / MR angiography", "If renovascular HTN suspected"],
    ["Chest X-ray", "Cardiomegaly, aortic knuckle, rib notching (coarctation)"],
  ]),
  spacer(),

  heading2("D. Management"),
  heading3("1. Lifestyle Modifications (Non-Pharmacological)"),
  bullet("Weight reduction: target BMI <25 kg/m² (each 10 kg weight loss → ~5–10 mmHg BP reduction)"),
  bullet("DASH diet: rich in fruits, vegetables, low-fat dairy, reduced saturated fat; reduces BP by 8–14 mmHg"),
  bullet("Sodium restriction: <6 g NaCl/day (<2.3 g Na⁺/day); reduces SBP by 2–8 mmHg"),
  bullet("Physical activity: ≥150 min/week of moderate-intensity aerobic exercise; reduces BP 4–9 mmHg"),
  bullet("Alcohol moderation: ≤2 units/day men, ≤1 unit/day women"),
  bullet("Smoking cessation: reduces overall cardiovascular risk"),
  bullet("Stress management, adequate sleep (treat OSA)"),

  heading3("2. Pharmacological Treatment"),
  body("Indications for drug therapy: Stage 2 HTN at any risk level; Stage 1 HTN with cardiovascular risk ≥10% or end-organ damage; all patients with persistent BP ≥160/100 mmHg."),
  spacer(),
  twoColTable([
    ["Drug Class", "Examples", "Key Indications/Notes"],
    ["ACE Inhibitors (ACEi)", "Ramipril, Enalapril, Lisinopril", "1st line in DM/proteinuria/CKD/HF; avoid in pregnancy; monitor K+ and creatinine; cause dry cough"],
    ["ARBs", "Losartan, Valsartan, Candesartan", "As ACEi but no cough; use if ACEi intolerant"],
    ["Calcium Channel Blockers (CCB)", "Amlodipine, Nifedipine (DHP); Diltiazem, Verapamil (non-DHP)", "1st line elderly/Afro-Caribbean; amlodipine causes ankle oedema; non-DHP can worsen HF"],
    ["Thiazide Diuretics", "Indapamide, Chlorthalidone, HCTZ", "1st line elderly, isolated systolic HTN, Afro-Caribbean; causes hypokalaemia, hyperuricaemia, hyperglycaemia"],
    ["Beta-Blockers", "Bisoprolol, Atenolol, Metoprolol", "Preferred in angina, post-MI, HFrEF, AF; avoid in asthma, T2DM; not 1st line in uncomplicated HTN"],
    ["Aldosterone antagonists", "Spironolactone, Eplerenone", "4th-line for resistant HTN; primary hyperaldosteronism; HFrEF"],
    ["Alpha-blockers", "Doxazosin, Prazosin", "Useful in BPH + HTN; phaeochromocytoma pre-operatively"],
    ["Central agents", "Methyldopa, Moxonidine", "Methyldopa is drug of choice in pregnancy"],
  ]),

  spacer(),
  heading3("3. Treatment Algorithm (NICE/JNC-8 Step Approach)"),
  bullet("Step 1: ACEi/ARB (age <55, non-Afro-Caribbean) OR CCB (age ≥55 or Afro-Caribbean)"),
  bullet("Step 2: ACEi/ARB + CCB"),
  bullet("Step 3: ACEi/ARB + CCB + Thiazide diuretic"),
  bullet("Step 4 (Resistant HTN): Add spironolactone 25–50 mg if K+ <4.5 mmol/L; OR add bisoprolol/doxazosin; refer to specialist"),
  bullet("Target BP: <140/90 mmHg (general); <130/80 mmHg in DM/CKD/CVD risk >10% (ACC/AHA); <150/90 mmHg in elderly >80 yrs"),

  heading3("4. Hypertensive Emergency Management"),
  bullet("Admit to ICU/HDU; continuous BP monitoring (intra-arterial line)"),
  bullet("IV antihypertensives: IV Labetalol, IV Nicardipine, IV Sodium Nitroprusside, IV Hydralazine"),
  bullet("Target: reduce MAP by ≤25% in first hour, then to 160/100 mmHg over next 2–6 hrs"),
  bullet("Do NOT reduce BP too rapidly (cerebral autoregulation failure → stroke)"),
  bullet("Specific conditions: Eclampsia → IV Magnesium sulphate + IV Hydralazine/Labetalol; Aortic dissection → target SBP <120 mmHg urgently"),
  noteBox("In resistant hypertension, always exclude secondary causes and medication non-compliance before escalating therapy."),
  spacer()
];

// ═══════════════════════════════════════════════════════════════════════════════
// Q4 – Short Notes
// ═══════════════════════════════════════════════════════════════════════════════
const q4 = [
  heading1("Q.4  Short Notes  [30 Marks – 6 marks each]"),

  heading2("4.1  Management of Supraventricular Tachycardia (SVT)"),
  body("SVT refers to a group of cardiac arrhythmias arising from above the Bundle of His. The most common types are AVNRT (AV Nodal Re-entry Tachycardia) and AVRT (AV Re-entry Tachycardia). ECG shows narrow complex tachycardia (HR 150–250 bpm) unless aberrant conduction."),

  heading3("Clinical Features"),
  bullet("Sudden onset palpitations, racing heart"),
  bullet("Dizziness, lightheadedness, near-syncope"),
  bullet("Dyspnoea, chest tightness"),
  bullet("Polyuria (ANP release) during episode"),
  bullet("Neck pounding (cannon A waves – AVNRT)"),

  heading3("Management"),
  bold_body("Step 1 – Assess Haemodynamic Stability", "Is the patient stable or unstable?"),
  bullet("Unstable (hypotension, chest pain, syncope, pulmonary oedema): DC cardioversion (synchronised) – 100–150 J biphasic; sedate before if conscious"),
  spacer(),
  bold_body("Step 2 – Stable Patient: Vagal Manoeuvres (First-line)", ""),
  bullet("Valsalva manoeuvre: sustained straining at 40 mmHg for 15 seconds – REVERT (modified Valsalva) is most effective – patient supine, legs elevated 45° post-strain → increases success to ~43%"),
  bullet("Carotid sinus massage (right side first, unilateral; contraindicated if carotid bruit or recent TIA/stroke)"),
  bullet("Ice-cold water facial immersion (diving reflex) – especially in children"),
  spacer(),
  bold_body("Step 3 – Drug Therapy (if vagal manoeuvres fail)", ""),
  bullet("Adenosine 6 mg rapid IV bolus (antecubital vein, followed by saline flush); if ineffective after 1–2 min → 12 mg; repeat 12 mg once more if needed"),
  subbullet("Mechanism: transiently blocks AV node"),
  subbullet("Side effects: flushing, transient asystole, chest tightness, bronchospasm"),
  subbullet("Contraindications: asthma, Wolf-Parkinson-White (WPW) with AF, heart transplant (use 3 mg)"),
  bullet("If adenosine fails or contraindicated: IV Verapamil 5–10 mg over 2 min (avoid in HFrEF, WPW, concurrent beta-blocker) OR IV Metoprolol 5 mg slowly"),
  bullet("Alternative: IV Flecainide (in structurally normal heart) or IV Amiodarone (broad spectrum)"),
  spacer(),
  bold_body("Step 4 – After Restoration of Sinus Rhythm", ""),
  bullet("12-lead ECG: look for pre-excitation (delta waves – WPW syndrome)"),
  bullet("Identify and treat underlying cause (thyrotoxicosis, electrolyte imbalance, caffeine, alcohol)"),
  bullet("For recurrent SVT: Refer to electrophysiology; Radiofrequency Catheter Ablation (RFA) is curative in >95%"),
  bullet("Long-term pharmacological prophylaxis: Verapamil, Diltiazem, beta-blockers, Flecainide/Propafenone"),
  noteBox("Adenosine is the drug of choice for acute SVT in haemodynamically stable patients. DC cardioversion for haemodynamic compromise."),
  spacer(),

  heading2("4.2  Hyaline Membrane Disease (Neonatal Respiratory Distress Syndrome)"),
  body("Hyaline Membrane Disease (HMD), also called Neonatal Respiratory Distress Syndrome (NRDS or RDS), is a condition of premature neonates caused by deficiency of pulmonary surfactant, leading to diffuse alveolar collapse, respiratory failure, and characteristic hyaline membrane formation on histology."),

  heading3("Definition & Pathophysiology"),
  bullet("Surfactant (phosphatidylcholine + phosphatidylglycerol) is produced by Type II pneumocytes from ~24 weeks; mature levels by 34–36 weeks"),
  bullet("Surfactant deficiency → high alveolar surface tension → alveolar collapse (atelectasis) at end-expiration"),
  bullet("Atelectasis → V/Q mismatch → hypoxaemia → pulmonary vasoconstriction → right-to-left shunting → worsening hypoxaemia"),
  bullet("Protein-rich exudate leaks into alveoli → lines alveolar walls as 'hyaline membranes' (eosinophilic on histology)"),

  heading3("Risk Factors"),
  bullet("Prematurity (<34 weeks gestational age) – most important risk factor"),
  bullet("Male sex, white race"),
  bullet("Maternal diabetes (insulin delays surfactant maturation)"),
  bullet("Second twin, caesarean section without labour"),
  bullet("Perinatal asphyxia, hypothermia"),

  heading3("Clinical Features"),
  bullet("Appears within minutes to 6 hours of birth"),
  bullet("Tachypnoea (RR >60/min), grunting (auto-PEEP mechanism)"),
  bullet("Subcostal, intercostal, suprasternal recession/retractions"),
  bullet("Nasal flaring"),
  bullet("Central cyanosis despite supplemental oxygen"),
  bullet("Reduced air entry bilaterally on auscultation"),
  bullet("Symptoms worsen over first 48–72 hours, then improve with surfactant production (if the neonate survives)"),

  heading3("Investigations"),
  bullet("CXR: ground-glass (reticulogranular) appearance of lungs; air bronchograms; low lung volumes; 'white-out' in severe cases"),
  bullet("ABG: hypoxaemia (PaO₂ <50 mmHg), hypercapnia, mixed respiratory and metabolic acidosis"),
  bullet("Lecithin:Sphingomyelin (L:S) ratio in amniotic fluid: <2:1 predicts immaturity"),
  bullet("Phosphatidylglycerol absent in amniotic fluid: poor surfactant maturity"),

  heading3("Management"),
  bold_body("Prevention", ""),
  bullet("Antenatal corticosteroids: Betamethasone 12 mg IM × 2 doses 24 hrs apart, given to mothers 24–34 weeks at risk of preterm delivery → accelerates fetal lung maturity by 48–72 hrs; reduces RDS severity and mortality by 40–50%"),
  bullet("Delay preterm delivery (tocolytics) to allow completion of steroid course"),
  spacer(),
  bold_body("Respiratory Support", ""),
  bullet("Mild: supplemental O₂ via headbox or nasal cannula to maintain SpO₂ 91–95%"),
  bullet("Moderate: early CPAP (Continuous Positive Airway Pressure) 5–8 cmH₂O via nasal prongs – prevents alveolar collapse, reduces intubation need"),
  bullet("Severe: mechanical ventilation (intubation) with permissive hypercapnia strategy"),
  bullet("HFOV (High-Frequency Oscillatory Ventilation) for refractory cases"),
  spacer(),
  bold_body("Surfactant Replacement Therapy (SRT) – Cornerstone of treatment", ""),
  bullet("Poractant alfa (Curosurf) 200 mg/kg intratracheally – first dose within 2 hours of birth ideally"),
  bullet("Beractant (Survanta) or calfactant (Infasurf) are alternatives"),
  bullet("Can be repeated (150 mg/kg) every 12 hrs if still requiring ≥30% FiO₂ (up to 2–3 doses)"),
  bullet("INSURE technique (INtubate-SURfactant-Extubate) – give surfactant then extubate to CPAP"),
  bullet("LISA/MIST technique: Less-Invasive Surfactant Administration via thin catheter while on CPAP – reduces intubation"),
  spacer(),
  bold_body("Supportive Care", ""),
  bullet("Temperature regulation: warmer/incubator; keep temperature 36.5–37.5°C"),
  bullet("IV fluids: 60–80 mL/kg/day initially; avoid overhydration (worsens pulmonary oedema)"),
  bullet("Nutrition: parenteral nutrition in first few days; enteral feeds when haemodynamically stable"),
  bullet("Antibiotics: broad-spectrum (ampicillin + gentamicin) empirically until sepsis excluded"),
  bullet("Treat PDA (Patent Ductus Arteriosus) if haemodynamically significant: Indomethacin or Ibuprofen IV"),
  noteBox("Antenatal corticosteroids + early postnatal surfactant therapy have dramatically reduced mortality from HMD. CPAP is now preferred over early intubation."),
  spacer(),

  heading2("4.3  Hypercalcaemia: Definition and Management"),
  body("Hypercalcaemia is defined as serum total calcium >2.6 mmol/L (10.4 mg/dL), or ionised calcium >1.3 mmol/L. It is considered severe when >3.5 mmol/L (14 mg/dL) or symptomatic."),

  heading3("Causes (Mnemonic: CHIMPANZEES)"),
  bullet("C – Calcium supplementation/thiazide diuretics"),
  bullet("H – Hyperparathyroidism (Primary – most common outpatient cause; adenoma 80%)"),
  bullet("I – Immobility (prolonged)"),
  bullet("M – Milk-alkali syndrome"),
  bullet("P – Paget's disease of bone"),
  bullet("A – Addison's disease (adrenal insufficiency)"),
  bullet("N – Neoplasm/Malignancy (2nd most common overall: PTHrP secretion – humoral hypercalcaemia of malignancy; osteolytic mets)"),
  bullet("Z – Zollinger-Ellison syndrome (rare)"),
  bullet("E – Excessive Vitamin D (granulomatous diseases: sarcoidosis, TB; lymphoma; exogenous Vit D toxicity)"),
  bullet("E – Endocrine (hyperthyroidism, phaeochromocytoma, VIPoma)"),
  bullet("S – Sarcoidosis / other granulomatous diseases"),

  heading3("Clinical Features – 'Bones, Stones, Groans, Psychic Moans'"),
  bullet("Bones: bone pain, osteitis fibrosa cystica, pathological fractures"),
  bullet("Stones: nephrolithiasis (calcium oxalate/phosphate), nephrocalcinosis, polyuria, polydipsia (nephrogenic DI)"),
  bullet("Groans: nausea, vomiting, anorexia, constipation, peptic ulcer disease, pancreatitis"),
  bullet("Psychic Moans: confusion, depression, lethargy, psychosis, reduced consciousness/coma in severe cases"),
  bullet("Cardiovascular: shortened QT interval on ECG, hypertension, bradycardia, cardiac arrest"),
  bullet("Muscle weakness, hyporeflexia"),

  heading3("Management"),
  bold_body("Mild-Moderate (Ca²⁺ 2.6–3.0 mmol/L, asymptomatic)", ""),
  bullet("Identify and treat underlying cause"),
  bullet("Oral hydration, avoid dehydration, avoid thiazides and Vit D supplements"),
  bullet("For primary hyperparathyroidism: parathyroidectomy if symptomatic or young age (<50), Ca²⁺ >0.25 mmol/L above normal, osteoporosis, renal involvement"),
  spacer(),
  bold_body("Severe/Symptomatic (Ca²⁺ >3.0–3.5 mmol/L or symptomatic) – Emergency Management", ""),
  bullet("1. IV 0.9% NaCl (isotonic saline): 200–500 mL/hr; initial cornerstone – corrects dehydration and promotes calciuresis; target urine output 100–150 mL/hr"),
  bullet("2. IV Bisphosphonates (after rehydration): Zoledronic acid 4 mg IV over 15 min OR Pamidronate 60–90 mg IV over 2–4 hrs; onset 2–4 days, peak 4–7 days; most potent and durable"),
  bullet("3. Calcitonin 4–8 IU/kg SC/IM every 6–12 hrs: rapid onset (4–6 hrs); reduces Ca²⁺ by 0.5 mmol/L; useful as bridge before bisphosphonates work; tachyphylaxis after 48 hrs"),
  bullet("4. Corticosteroids (Hydrocortisone/Prednisolone): useful in granulomatous disease (sarcoidosis, TB) and haematological malignancy (myeloma, lymphoma); blocks intestinal Ca²⁺ absorption and 1,25-VitD production"),
  bullet("5. Denosumab 120 mg SC: for bisphosphonate-refractory or renal failure patients (RANKL inhibitor)"),
  bullet("6. Dialysis (haemodialysis with low-calcium dialysate): reserved for life-threatening hypercalcaemia with renal failure or cardiac arrhythmia"),
  bullet("7. Cinacalcet (calcimimetic): for primary hyperparathyroidism if surgery not feasible"),
  bullet("8. Furosemide: only after adequate rehydration if volume overloaded; not routine (previously overused)"),
  noteBox("Bisphosphonates + IV saline are the mainstays of acute severe hypercalcaemia treatment. Always identify and treat the underlying cause."),
  spacer(),

  heading2("4.4  Patient with Shortness of Breath and Haemoglobin of 7 g/dL – Evaluate and Manage"),
  body("A patient presenting with shortness of breath (SOB) and a haemoglobin (Hb) of 7 g/dL has significant anaemia. Hb <7 g/dL represents severe anaemia. The evaluation must identify the type, cause, and severity, and management must address both the symptom and underlying aetiology."),

  heading3("Evaluation"),
  bold_body("History", ""),
  bullet("SOB: at rest or exertion, onset, progression, orthopnoea, PND (cardiac cause vs. anaemia)"),
  bullet("Symptoms of anaemia: fatigue, pallor, palpitations, dizziness, tinnitus, headache"),
  bullet("Cause of anaemia:"),
  subbullet("Blood loss: haematemesis, melaena, haematochezia, heavy menstrual bleeding (menorrhagia), haematuria"),
  subbullet("Nutritional deficiency: poor diet, vegetarian/vegan (B12, iron), malabsorption (coeliac, Crohn's)"),
  subbullet("Chronic disease: rheumatoid arthritis, CKD, malignancy, chronic infection"),
  subbullet("Haemolysis: dark urine, jaundice, sickle cell/thalassaemia family history"),
  subbullet("Bone marrow failure: easy bruising, recurrent infections, purpura"),
  bullet("Drug history: NSAIDs (GI bleeding), methotrexate, chemotherapy"),
  bullet("Family history: haemoglobinopathies (sickle cell, thalassaemia)"),
  spacer(),
  bold_body("Examination", ""),
  bullet("Vitals: tachycardia (compensatory), hypotension, tachypnoea, low SpO₂"),
  bullet("Pallor: conjunctival, palmar, mucosal pallor – most reliable sign"),
  bullet("Jaundice: haemolytic anaemia"),
  bullet("Koilonychia (spoon-shaped nails), angular stomatitis, glossitis: iron deficiency"),
  bullet("Peripheral neuropathy, subacute combined degeneration: B12 deficiency"),
  bullet("Lymphadenopathy, splenomegaly, hepatomegaly: haematological malignancy"),
  bullet("Flow murmur (systolic ejection murmur) over precordium due to hyperdynamic circulation"),
  bullet("Signs of CCF: raised JVP, peripheral oedema, bibasal crackles"),
  spacer(),

  heading3("Investigations"),
  bullet("CBC with differential: confirm Hb, MCV (microcytic <80 fL / normocytic 80–100 fL / macrocytic >100 fL)"),
  bullet("Peripheral blood smear: morphology (target cells, spherocytes, hypersegmented neutrophils, sickling)"),
  bullet("Reticulocyte count: elevated in haemolysis/haemorrhage (regenerative); low in aplasia/deficiency (hypoproliferative)"),
  twoColTable([
    ["MCV Pattern", "Likely Cause", "Key Tests"],
    ["Microcytic (MCV <80)", "Iron deficiency, Thalassaemia, ACD (can be normocytic), Sideroblastic", "Serum iron, TIBC, ferritin, HbEPEP"],
    ["Normocytic (MCV 80–100)", "ACD, renal failure, hypothyroid, aplastic anaemia, early haemolysis", "Reticulocyte count, renal function, TFTs, bone marrow biopsy"],
    ["Macrocytic (MCV >100)", "B12/Folate deficiency, alcohol, hypothyroid, liver disease, drugs", "Serum B12, folate, homocysteine, MMA, TFTs"],
  ]),
  bullet("Coombs test (DAT): positive in autoimmune haemolytic anaemia"),
  bullet("Renal function (eGFR): anaemia of CKD"),
  bullet("Thyroid function tests"),
  bullet("LFTs, serum bilirubin (indirect), LDH, haptoglobin: haemolysis screen"),
  bullet("Bone marrow aspirate + trephine: aplastic anaemia, leukaemia, myelodysplasia"),
  bullet("ECG: tachycardia, ischaemic changes (demand ischaemia in severe anaemia)"),
  bullet("Chest X-ray: cardiomegaly, pulmonary oedema"),
  bullet("Endoscopy (upper/lower GI): if GI blood loss suspected"),
  spacer(),

  heading3("Management"),
  bold_body("Immediate/Emergency (Hb 7 g/dL with symptoms)", ""),
  bullet("High-flow O₂ if SpO₂ <94%; patient positioning (upright for SOB)"),
  bullet("IV access, IV fluids if haemodynamically compromised"),
  bullet("Blood transfusion: indicated if Hb <7 g/dL with symptoms (SOB, tachycardia, cardiac ischaemia) or Hb <8 g/dL in cardiac disease"),
  subbullet("Transfuse: 1 unit packed red blood cells (PRBCs) at a time; each unit raises Hb by ~1 g/dL"),
  subbullet("Pre-transfusion: send crossmatch/group and save; consent patient"),
  subbullet("Monitor for transfusion reactions: febrile, haemolytic, TRALI"),
  spacer(),
  bold_body("Specific Treatment by Cause", ""),
  bullet("Iron deficiency anaemia: Oral ferrous sulphate 200 mg TDS (take with Vit C, avoid with tea/calcium); IV iron (ferric carboxymaltose) if intolerant or malabsorption; treat source of bleeding"),
  bullet("B12 deficiency: IM Hydroxocobalamin 1 mg alternate days × 6 doses → then 1 mg every 3 months lifelong if pernicious anaemia; oral B12 if dietary deficiency"),
  bullet("Folate deficiency: Folic acid 5 mg OD × 4 months (always give with B12 if uncertain to avoid unmasking subacute combined degeneration)"),
  bullet("Anaemia of CKD: Erythropoiesis-stimulating agents (ESAs – darbepoetin alfa, epoetin alfa) + IV iron; target Hb 10–12 g/dL"),
  bullet("Haemolytic anaemia: treat underlying cause; corticosteroids (prednisolone 1 mg/kg/day) for AIHA; rituximab for refractory cases"),
  bullet("Aplastic anaemia: anti-thymocyte globulin (ATG) + cyclosporin; allogeneic HSCT if young with matched donor"),
  noteBox("Always identify the underlying cause. Blood transfusion treats the immediate risk; specific therapy prevents recurrence."),
  spacer(),

  heading2("4.5  Giddiness: Causes and Investigations"),
  body("Giddiness (dizziness/vertigo) is a common presenting symptom encompassing several distinct sensations: vertigo (false sense of self or environmental rotation), presyncope (feeling of impending fainting), disequilibrium (unsteadiness/balance disturbance), and non-specific lightheadedness. Systematic evaluation is key to identifying the cause."),

  heading3("Causes of Giddiness"),
  heading3("A. Vertigo"),
  bold_body("1. Peripheral Vertigo (inner ear / vestibular nerve)", ""),
  bullet("Benign Paroxysmal Positional Vertigo (BPPV): most common; brief episodes (<1 min) triggered by head position change; Dix-Hallpike positive; due to otolith displacement"),
  bullet("Menière's Disease: triad of episodic vertigo + unilateral sensorineural hearing loss + tinnitus; endolymphatic hydrops"),
  bullet("Vestibular Neuritis/Labyrinthitis: sudden severe vertigo, continuous, post-viral; nausea/vomiting; no hearing loss (neuritis) vs. hearing loss (labyrinthitis)"),
  bullet("Acoustic Neuroma (Vestibular Schwannoma): gradual progressive unilateral SNHL + tinnitus + imbalance"),
  bullet("Otosclerosis, chronic otitis media (perilymph fistula), ototoxic drugs (aminoglycosides, cisplatin, furosemide)"),

  bold_body("2. Central Vertigo (brainstem/cerebellum)", ""),
  bullet("Posterior fossa TIA/stroke (vertebrobasilar insufficiency): sudden onset; direction-changing nystagmus; HINTS exam + (Head Impulse test Normal, direction-changing Nystagmus, Skew deviation = central cause)"),
  bullet("Cerebellar infarction/haemorrhage: severe vertigo + truncal ataxia + vomiting; inability to walk"),
  bullet("Multiple sclerosis: demyelination of vestibular pathways; younger patients"),
  bullet("Posterior fossa tumours, Arnold-Chiari malformation"),
  bullet("Wernicke's encephalopathy (thiamine deficiency): triad – vertigo/ataxia, ophthalmoplegia, confusion"),

  heading3("B. Presyncope / Near-Syncope"),
  bullet("Cardiac: arrhythmias (Brady/tachy), valvular disease (AS), hypertrophic cardiomyopathy, MI"),
  bullet("Orthostatic hypotension: fall in SBP >20 or DBP >10 mmHg on standing; autonomic neuropathy (DM), dehydration, drugs (antihypertensives, diuretics)"),
  bullet("Vasovagal syncope: emotional trigger, pain, prolonged standing"),
  bullet("Carotid sinus hypersensitivity"),
  bullet("Hypovolaemia: haemorrhage, dehydration"),

  heading3("C. Other Systemic Causes"),
  bullet("Anaemia (Hb <7 g/dL): cerebral hypoperfusion → giddiness and presyncope"),
  bullet("Hypoglycaemia: sweating, tremor, confusion, giddiness (critical to exclude)"),
  bullet("Hypothyroidism: cerebellar ataxia, giddiness"),
  bullet("Hyponatraemia, hypokalaemia, hypocalcaemia"),
  bullet("Cervicogenic dizziness: cervical spondylosis → vertebral artery compression"),
  bullet("Anxiety/panic disorders, hyperventilation"),
  bullet("Drugs: antihypertensives, sedatives, benzodiazepines, aminoglycosides, antiepileptics"),
  spacer(),

  heading3("D. Investigations"),
  heading3("Bedside"),
  bullet("Vitals: BP lying and standing (orthostatic hypotension), HR, temperature"),
  bullet("Dix-Hallpike test: BPPV – latency (2–20 s), rotatory nystagmus, fatigable"),
  bullet("HINTS exam (for acute vestibular syndrome): Head impulse test, Nystagmus type, Test of Skew – HINTS+ indicates central cause; HINTS- indicates peripheral"),
  bullet("Romberg's test: positive (falls with eyes closed) in posterior column/vestibular disease"),
  bullet("Finger-nose test, heel-shin test: cerebellar ataxia"),
  bullet("Tandem gait, Unterberger stepping test"),
  bullet("Otoscopy: otitis media, cholesteatoma"),
  spacer(),

  heading3("Laboratory Investigations"),
  bullet("CBP: anaemia as cause of presyncope"),
  bullet("Blood glucose (finger prick and fasting serum): hypoglycaemia"),
  bullet("Serum electrolytes (Na, K, Ca): electrolyte imbalances"),
  bullet("Thyroid function tests: hypothyroidism"),
  bullet("Serum B12 and folate: peripheral neuropathy causing imbalance"),
  bullet("Serum lipids, HbA1c, fasting glucose: cardiovascular risk factors for vertebrobasilar disease"),
  bullet("Thiamine levels if Wernicke's suspected"),
  spacer(),

  heading3("Cardiac Investigations"),
  bullet("12-lead ECG: arrhythmias, heart block, QT prolongation"),
  bullet("Holter monitor (24–48 hr ambulatory ECG): intermittent arrhythmias"),
  bullet("Echocardiogram: valvular disease, cardiomyopathy, LV function"),
  bullet("Tilt-table test: vasovagal/orthostatic hypotension confirmation"),
  spacer(),

  heading3("Audiological / Vestibular"),
  bullet("Pure tone audiometry: sensorineural hearing loss (acoustic neuroma, Menière's, labyrinthitis)"),
  bullet("Electronystagmography (ENG) / Videonystagmography (VNG): assess vestibular function"),
  bullet("VEMP (Vestibular Evoked Myogenic Potentials): saccular/utricular function"),
  spacer(),

  heading3("Imaging"),
  bullet("MRI brain with gadolinium (preferred): posterior fossa tumours, acoustic neuroma, brainstem/cerebellar infarction, MS plaques"),
  bullet("CT head (without contrast): if haemorrhage suspected (rapid onset) or MRI not available"),
  bullet("MR Angiography (vertebrobasilar system): if vertebrobasilar insufficiency suspected"),
  bullet("CT/MRI temporal bones: if petrous bone pathology suspected"),
  noteBox("BPPV is the most common cause of vertigo and is treated with Epley manoeuvre (particle repositioning). A posterior fossa stroke must always be excluded in new-onset vertigo with risk factors."),
  spacer()
];

// ═══════════════════════════════════════════════════════════════════════════════
// Q5 – ABG (10 marks)
// ═══════════════════════════════════════════════════════════════════════════════
const q5 = [
  heading1("Q.5  Components of ABG and ABG Interpretation in Various Respiratory Diseases  [10 Marks]"),

  heading2("A. Components of Arterial Blood Gas (ABG)"),
  body("Arterial blood gas analysis is performed on arterialised blood (usually radial artery) and provides vital information about respiratory function, metabolic status, and acid-base balance."),
  spacer(),
  twoColTable([
    ["Parameter", "Normal Range", "Clinical Significance"],
    ["pH", "7.35–7.45", "Measure of hydrogen ion concentration; <7.35 = acidosis; >7.45 = alkalosis"],
    ["PaO₂ (Partial pressure of O₂)", "80–100 mmHg (10.6–13.3 kPa)", "Oxygenation; <60 mmHg = respiratory failure type I; reference to FiO₂ important"],
    ["PaCO₂ (Partial pressure of CO₂)", "35–45 mmHg (4.7–6.0 kPa)", "Ventilation; >45 = hypercapnia (hypoventilation); <35 = hypocapnia (hyperventilation)"],
    ["HCO₃⁻ (Bicarbonate)", "22–26 mmol/L", "Metabolic component; raised in metabolic alkalosis/compensated resp. acidosis; low in metabolic acidosis"],
    ["Base Excess (BE)", "-2 to +2 mmol/L", "Amount of base needed to restore pH to 7.40; >+2 = metabolic alkalosis; <-2 = metabolic acidosis"],
    ["SaO₂ (O₂ saturation)", "94–98%", "Percentage of Hb saturated with O₂; unreliable in dyshemoglobinaemias (CO poisoning: SpO₂ falsely normal)"],
    ["FiO₂", "0.21 (room air) – 1.0", "Fraction of inspired oxygen; used to calculate P/F ratio and A-a gradient"],
    ["P/F Ratio (PaO₂/FiO₂)", ">400 normal; <200 = ARDS", "Severity of hypoxaemia; marker of respiratory failure"],
    ["A-a gradient", "<10–15 mmHg on room air", "Difference between alveolar and arterial O₂; elevated in V/Q mismatch, shunt, diffusion impairment"],
    ["Lactate", "<2 mmol/L", "Tissue hypoxia/anaerobic metabolism; >4 mmol/L = severe shock/sepsis"],
    ["Anion Gap (AG)", "8–12 mmol/L", "Na⁺ – (Cl⁻ + HCO₃⁻); elevated in metabolic acidosis (MUDPILES)"],
  ]),
  spacer(),

  heading2("B. Systematic ABG Interpretation"),
  heading3("Step-by-Step Approach"),
  bullet("Step 1: Assess pH – <7.35 (acidosis) or >7.45 (alkalosis)"),
  bullet("Step 2: Identify primary disorder – look at PaCO₂ and HCO₃⁻"),
  subbullet("Respiratory acidosis: pH↓ PaCO₂↑"),
  subbullet("Respiratory alkalosis: pH↑ PaCO₂↓"),
  subbullet("Metabolic acidosis: pH↓ HCO₃⁻↓"),
  subbullet("Metabolic alkalosis: pH↑ HCO₃⁻↑"),
  bullet("Step 3: Assess compensation – appropriate compensation indicates single disorder"),
  subbullet("Respiratory acidosis: HCO₃⁻ rises by 1 mmol/L per 10 mmHg rise in PaCO₂ (acute); 3.5 per 10 (chronic)"),
  subbullet("Metabolic acidosis: expected PaCO₂ = (1.5 × HCO₃⁻) + 8 ± 2 (Winter's formula)"),
  bullet("Step 4: Calculate anion gap if metabolic acidosis present"),
  bullet("Step 5: Assess oxygenation – PaO₂, P/F ratio, A-a gradient"),
  bullet("Step 6: Assess for mixed disorders if compensation inadequate"),
  spacer(),

  heading2("C. ABG Patterns in Common Respiratory Diseases"),

  heading3("1. Acute Severe Asthma (Life-Threatening)"),
  twoColTable([
    ["pH", "PaO₂", "PaCO₂", "HCO₃⁻", "SaO₂"],
    ["7.20–7.30 (acidosis)", "<60 mmHg", ">45 mmHg (RISING!)", "Normal/slightly low", "<90%"],
  ]),
  bullet("Pattern: Type II Respiratory Failure (hypoxaemia + hypercapnia) – indicates impending respiratory arrest"),
  bullet("Significance: Normal or rising PaCO₂ in an acute asthmatic = DANGEROUS (patient too exhausted to hyperventilate)"),
  bullet("Mild/Moderate attack: PaCO₂ is LOW (hyperventilation); normocapnia in an attack = warning sign"),
  spacer(),

  heading3("2. COPD Exacerbation"),
  twoColTable([
    ["pH", "PaO₂", "PaCO₂", "HCO₃⁻", "Notes"],
    ["7.20–7.30 (acute)", "<60 mmHg", ">55–60 mmHg", "Elevated (chronic comp.)", "Acute-on-chronic Type II RF"],
  ]),
  bullet("Chronic COPD: compensated respiratory acidosis – pH near-normal (7.35–7.40), elevated PaCO₂ (50–60), elevated HCO₃⁻ (28–32)"),
  bullet("Acute exacerbation: pH falls (decompensated), PaCO₂ rises, HCO₃⁻ further elevated"),
  bullet("O₂ therapy: controlled O₂ via venturi mask (24–28% FiO₂); avoid high-flow O₂ (suppresses hypoxic drive)"),
  bullet("Treatment: NIV (BiPAP) – indicated if pH <7.35 and PaCO₂ >45 despite medical therapy"),
  spacer(),

  heading3("3. Pneumonia (Severe / Type I Respiratory Failure)"),
  twoColTable([
    ["pH", "PaO₂", "PaCO₂", "HCO₃⁻", "Notes"],
    ["7.45–7.50 (alkalosis)", "<60 mmHg", "<35 mmHg (hypocapnia)", "Normal/slightly low", "Type I RF + respiratory alkalosis"],
  ]),
  bullet("Pattern: Hypoxaemia drives hyperventilation → respiratory alkalosis"),
  bullet("Elevated A-a gradient (V/Q mismatch due to alveolar consolidation)"),
  bullet("Severe: P/F ratio <300 (moderate–severe), <200 (severe)"),
  spacer(),

  heading3("4. ARDS (Acute Respiratory Distress Syndrome)"),
  twoColTable([
    ["pH", "PaO₂", "PaCO₂", "HCO₃⁻", "P/F Ratio"],
    ["Variable (acidosis if severe)", "<60 mmHg (refractory)", "Low initially; may rise", "Variable", "<200 (moderate); <100 (severe)"],
  ]),
  bullet("Hallmark: Refractory hypoxaemia (not improved with supplemental O₂ alone)"),
  bullet("Berlin criteria: P/F <200 (moderate) and <100 (severe) with bilateral infiltrates on CXR + not fully explained by fluid overload"),
  bullet("Management: Low tidal volume ventilation (6 mL/kg IBW), PEEP, prone positioning, permissive hypercapnia"),
  spacer(),

  heading3("5. Pulmonary Embolism (PE)"),
  twoColTable([
    ["pH", "PaO₂", "PaCO₂", "HCO₃⁻", "Notes"],
    ["7.45–7.50", "<80 mmHg (acute)", "<35 mmHg", "Normal/slightly low", "Type I RF + respiratory alkalosis"],
  ]),
  bullet("Classic: hypoxaemia + hypocapnia + respiratory alkalosis"),
  bullet("Elevated A-a gradient (dead-space ventilation)"),
  bullet("Can have normal ABG in small PE"),
  spacer(),

  heading3("6. Diabetic Ketoacidosis (DKA)"),
  twoColTable([
    ["pH", "PaO₂", "PaCO₂", "HCO₃⁻", "Notes"],
    ["<7.30 (severe acidosis)", "Normal", "Low (20–30) compensatory", "<15 mmol/L", "High Anion Gap Metabolic Acidosis"],
  ]),
  bullet("High anion gap metabolic acidosis + Kussmaul breathing (compensatory hyperventilation drives down PaCO₂)"),
  bullet("AG = Na – (Cl + HCO₃⁻); typically >16 in DKA"),
  spacer(),

  heading3("7. Opioid/Sedative Overdose (Respiratory Depression)"),
  twoColTable([
    ["pH", "PaO₂", "PaCO₂", "HCO₃⁻", "Notes"],
    ["<7.35 (acidosis)", "↓↓", "↑↑ (>60 mmHg)", "Normal (acute) / elevated (chronic)", "Acute Type II RF"],
  ]),
  bullet("Pure respiratory acidosis with no metabolic compensation (acute onset)"),
  bullet("Management: Naloxone IV, airway support, mechanical ventilation if severe"),
  spacer(),

  heading2("D. Summary Table"),
  twoColTable([
    ["Condition", "pH", "PaCO₂", "HCO₃⁻", "Type of Failure"],
    ["Asthma (severe/life-threatening)", "Low", "High (rising)", "Normal/low", "Type II"],
    ["COPD (acute exacerbation)", "Low", "Very high", "High", "Acute on Chronic Type II"],
    ["COPD (stable, compensated)", "Normal", "High", "High", "Compensated resp. acidosis"],
    ["Pneumonia", "High", "Low", "Normal", "Type I"],
    ["ARDS", "Low/variable", "Low/high", "Variable", "Type I (severe, refractory)"],
    ["Pulmonary Embolism", "High", "Low", "Normal", "Type I"],
    ["DKA", "Low", "Low", "Very low", "High-AG metabolic acidosis"],
    ["Opioid overdose", "Low", "Very high", "Normal", "Acute Type II"],
  ]),
  noteBox("Type I Respiratory Failure: PaO₂ <60 mmHg with normal or low PaCO₂ (hypoxaemia without hypercapnia). Type II Respiratory Failure: PaO₂ <60 mmHg AND PaCO₂ >50 mmHg (hypoxaemia + hypercapnia = ventilatory failure)."),
  spacer()
];

// ═══════════════════════════════════════════════════════════════════════════════
// ASSEMBLE DOCUMENT
// ═══════════════════════════════════════════════════════════════════════════════
const allContent = [
  ...titleSection,
  ...q1,
  HR(),
  ...q2,
  HR(),
  ...q3,
  HR(),
  ...q4,
  HR(),
  ...q5,
  spacer(),
  new Paragraph({
    children: [new TextRun({ text: "--- END OF ANSWER SHEET ---", bold: true, size: 22, font: "Calibri", color: "888888" })],
    alignment: AlignmentType.CENTER,
    spacing: { before: 400 }
  })
];

const doc = new Document({
  creator: "Orris Medical AI",
  title: "R2 General Medicine Exam – Model Answer Sheet (May 2026)",
  description: "Comprehensive model answers for SMT NHLMMC R2 General Medicine exam",
  styles: {
    default: {
      document: {
        run: { font: "Calibri", size: 22 }
      }
    }
  },
  numbering: {
    config: [
      {
        reference: "default-bullets",
        levels: [
          { level: 0, format: "bullet", text: "\u2022", alignment: AlignmentType.LEFT, style: { paragraph: { indent: { left: 360, hanging: 260 } } } },
          { level: 1, format: "bullet", text: "\u25E6", alignment: AlignmentType.LEFT, style: { paragraph: { indent: { left: 720, hanging: 260 } } } }
        ]
      }
    ]
  },
  sections: [{
    properties: {
      page: {
        margin: { top: 1080, bottom: 1080, left: 1080, right: 1080 }
      }
    },
    headers: {
      default: new Header({
        children: [new Paragraph({
          children: [
            new TextRun({ text: "SMT NHLMMC – R2 General Medicine | May 2026 | MODEL ANSWER SHEET", size: 18, color: "888888", font: "Calibri" })
          ],
          alignment: AlignmentType.CENTER,
          border: { bottom: { style: BorderStyle.SINGLE, size: 2, color: "CCCCCC" } }
        })]
      })
    },
    footers: {
      default: new Footer({
        children: [new Paragraph({
          children: [
            new TextRun({ text: "Page ", size: 18, font: "Calibri", color: "888888" }),
            new TextRun({ children: [PageNumber.CURRENT], size: 18, font: "Calibri", color: "888888" }),
            new TextRun({ text: " of ", size: 18, font: "Calibri", color: "888888" }),
            new TextRun({ children: [PageNumber.TOTAL_PAGES], size: 18, font: "Calibri", color: "888888" }),
          ],
          alignment: AlignmentType.CENTER
        })]
      })
    },
    children: allContent
  }]
});

Packer.toBuffer(doc).then(buffer => {
  fs.writeFileSync("/home/daytona/workspace/r2-exam-answer-sheet/R2_General_Medicine_Answer_Sheet_May2026.docx", buffer);
  console.log("SUCCESS: Document created.");
}).catch(err => {
  console.error("ERROR:", err);
  process.exit(1);
});