from reportlab.lib.pagesizes import A4
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.units import cm, mm
from reportlab.lib import colors
from reportlab.platypus import (SimpleDocTemplate, Paragraph, Spacer, 
                                 Table, TableStyle, HRFlowable, 
                                 KeepTogether, PageBreak)
from reportlab.lib.enums import TA_LEFT, TA_CENTER, TA_JUSTIFY
from reportlab.platypus import ListFlowable, ListItem

doc = SimpleDocTemplate(
    "/tmp/workspace/surgery-exam-answers/Surgery_Exam_Answers.pdf",
    pagesize=A4,
    rightMargin=2*cm, leftMargin=2*cm,
    topMargin=2*cm, bottomMargin=2*cm
)

styles = getSampleStyleSheet()

# Custom styles
title_style = ParagraphStyle('Title', parent=styles['Title'],
    fontSize=16, textColor=colors.HexColor('#1a2744'),
    spaceAfter=4, fontName='Helvetica-Bold', alignment=TA_CENTER)

subtitle_style = ParagraphStyle('Subtitle', parent=styles['Normal'],
    fontSize=10, textColor=colors.HexColor('#444444'),
    spaceAfter=12, alignment=TA_CENTER)

q_heading_style = ParagraphStyle('QHeading', parent=styles['Normal'],
    fontSize=13, textColor=colors.white,
    fontName='Helvetica-Bold', spaceBefore=14, spaceAfter=6,
    backColor=colors.HexColor('#1a2744'), leftIndent=-10, rightIndent=-10,
    borderPadding=(6, 10, 6, 10))

sub_heading_style = ParagraphStyle('SubHeading', parent=styles['Normal'],
    fontSize=11, textColor=colors.HexColor('#1a2744'),
    fontName='Helvetica-Bold', spaceBefore=10, spaceAfter=4,
    leftIndent=0)

sub2_heading_style = ParagraphStyle('Sub2Heading', parent=styles['Normal'],
    fontSize=10.5, textColor=colors.HexColor('#2c5282'),
    fontName='Helvetica-Bold', spaceBefore=8, spaceAfter=3)

body_style = ParagraphStyle('Body', parent=styles['Normal'],
    fontSize=9.5, leading=14, textColor=colors.HexColor('#222222'),
    spaceAfter=5, alignment=TA_JUSTIFY)

bullet_style = ParagraphStyle('Bullet', parent=styles['Normal'],
    fontSize=9.5, leading=13, leftIndent=15, spaceAfter=3,
    bulletIndent=5, textColor=colors.HexColor('#222222'))

ref_style = ParagraphStyle('Ref', parent=styles['Normal'],
    fontSize=8, textColor=colors.HexColor('#666666'),
    fontName='Helvetica-Oblique', spaceBefore=10, spaceAfter=2)

mark_style = ParagraphStyle('Mark', parent=styles['Normal'],
    fontSize=9, textColor=colors.HexColor('#c05621'),
    fontName='Helvetica-Bold', spaceAfter=2)

story = []

# ─── TITLE PAGE HEADER ────────────────────────────────────────────────────────
story.append(Paragraph("MBBS PHASE 3 PART 2 — PAPER 2", title_style))
story.append(Paragraph("Surgery Long Answer Questions — Model Answers", subtitle_style))
story.append(Paragraph("Reference: Bailey & Love, Schwartz's Principles of Surgery, Fischer's Mastery of Surgery, Miller's Anesthesia, Sleisenger & Fordtran's Gastroenterology", ref_style))
story.append(HRFlowable(width="100%", thickness=2, color=colors.HexColor('#1a2744')))
story.append(Spacer(1, 10))

# ══════════════════════════════════════════════════════════════════════════════
# Q2 — BREAST (20 marks)
# ══════════════════════════════════════════════════════════════════════════════
story.append(Paragraph("Q2. Describe Anatomy of Breast with Lymphatic Drainage, TNM Staging, and Types of Breast Cancer", q_heading_style))
story.append(Paragraph("[20 Marks]", mark_style))

story.append(Paragraph("A. Anatomy of the Breast", sub_heading_style))
story.append(Paragraph(
    "The breast is a modified sweat gland (apocrine) lying in the superficial fascia of the anterior chest wall, overlying the pectoralis major and serratus anterior muscles. It extends vertically from the 2nd to the 6th rib, and transversely from the lateral border of the sternum to the mid-axillary line. An axillary tail (tail of Spence) projects through the deep fascia.",
    body_style))

story.append(Paragraph("Structure:", sub2_heading_style))
story.append(Paragraph("• <b>Glandular tissue:</b> 15–20 lobes arranged radially, each lobe comprising lobules of secretory acini. Each lobe drains via a lactiferous duct (2–4 mm diameter) opening at the nipple. The ducts dilate to form the <b>lactiferous sinus</b> (ampulla) beneath the areola.", bullet_style))
story.append(Paragraph("• <b>Cooper's ligaments:</b> Fibrous septa connecting glandular tissue to the overlying skin and dermis, providing structural support. Infiltration by tumour causes the characteristic 'peau d'orange' (skin dimpling) appearance.", bullet_style))
story.append(Paragraph("• <b>Nipple-Areola Complex:</b> Contains smooth muscle fibres, sebaceous glands (Montgomery's tubercles), and multiple lactiferous duct openings.", bullet_style))
story.append(Paragraph("• <b>Retromammary space:</b> A potential space between the posterior capsule of the breast and pectoral fascia, allowing breast mobility.", bullet_style))

story.append(Paragraph("Blood Supply:", sub2_heading_style))
story.append(Paragraph("• <b>Medial:</b> Internal mammary artery (internal thoracic artery) — principal supply, perforating branches through intercostal spaces 2–4.", bullet_style))
story.append(Paragraph("• <b>Lateral:</b> Lateral thoracic artery (branch of axillary), thoracoacromial artery, anterior intercostal arteries.", bullet_style))

story.append(Paragraph("B. Lymphatic Drainage", sub_heading_style))
story.append(Paragraph(
    "The lymphatic drainage of the breast is clinically important as it is the primary route of metastatic spread. The breast has a rich interconnecting network of lymphatics in the dermis and subdermal plexus.",
    body_style))
story.append(Paragraph("• <b>Axillary nodes (75% of drainage):</b> The most important drainage pathway. Pectoral (anterior) nodes receive drainage from the breast directly. These drain upward to the central nodes, then to the apical (subclavian) nodes, and finally to the supraclavicular nodes.", bullet_style))
story.append(Paragraph("• <b>Internal mammary nodes (25%):</b> Receive lymph mainly from the medial quadrants of the breast along the perforating branches of the internal mammary artery. These are not amenable to routine surgical clearance.", bullet_style))
story.append(Paragraph("• <b>Interpectoral nodes (Rotter's nodes):</b> Lie between pectoralis major and minor; important in Patey's modified radical mastectomy.", bullet_style))
story.append(Paragraph("• <b>Posterior intercostal nodes:</b> Drain toward the thoracic duct (left) or right lymphatic duct.", bullet_style))
story.append(Paragraph("• <b>Subphrenic and subareolar plexus:</b> Connects with the contralateral breast, abdominal wall, and internal mammary chain.", bullet_style))

story.append(Paragraph("Axillary Nodal Levels (Berg's Classification):", sub2_heading_style))
data = [
    ['Level', 'Location', 'Clinical Significance'],
    ['Level I (Low axilla)', 'Lateral to pectoralis minor', 'First echelon nodes; sampled in SLNB'],
    ['Level II (Mid axilla)', 'Posterior to pectoralis minor (includes Rotter\'s)', 'Cleared in modified radical mastectomy'],
    ['Level III (Apical)', 'Medial to pectoralis minor, below clavicle', 'Cleared only in full axillary dissection'],
]
t = Table(data, colWidths=[4*cm, 6*cm, 6*cm])
t.setStyle(TableStyle([
    ('BACKGROUND', (0,0), (-1,0), colors.HexColor('#1a2744')),
    ('TEXTCOLOR', (0,0), (-1,0), colors.white),
    ('FONTNAME', (0,0), (-1,0), 'Helvetica-Bold'),
    ('FONTSIZE', (0,0), (-1,-1), 9),
    ('GRID', (0,0), (-1,-1), 0.5, colors.grey),
    ('ROWBACKGROUNDS', (0,1), (-1,-1), [colors.HexColor('#f0f4fa'), colors.white]),
    ('VALIGN', (0,0), (-1,-1), 'TOP'),
    ('TOPPADDING', (0,0), (-1,-1), 4),
    ('BOTTOMPADDING', (0,0), (-1,-1), 4),
]))
story.append(t)
story.append(Spacer(1, 8))

story.append(Paragraph("C. TNM Staging of Breast Cancer (AJCC 8th Edition)", sub_heading_style))
story.append(Paragraph(
    "TNM staging combines clinical and pathological data and has important prognostic and therapeutic implications.",
    body_style))

data2 = [
    ['T — Primary Tumour', ''],
    ['Tis', 'Carcinoma in situ (DCIS, LCIS, Paget\'s of nipple)'],
    ['T1', 'Tumour ≤20 mm (T1a ≤5 mm; T1b >5–10 mm; T1c >10–20 mm)'],
    ['T2', 'Tumour >20 mm and ≤50 mm'],
    ['T3', 'Tumour >50 mm'],
    ['T4', 'Any size with direct extension to chest wall or skin (T4a–d); T4d = inflammatory carcinoma'],
    ['N — Regional Lymph Nodes', ''],
    ['N0', 'No regional lymph node metastasis'],
    ['N1', 'Movable ipsilateral axillary LN metastasis (Level I–II)'],
    ['N2', 'Fixed/matted axillary LN, or ipsilateral internal mammary LN'],
    ['N3', 'Infraclavicular, supraclavicular, or internal mammary + axillary LN'],
    ['M — Distant Metastasis', ''],
    ['M0', 'No clinical/radiological distant metastasis'],
    ['M1', 'Distant metastasis detected (bone, lung, liver, brain)'],
]
t2 = Table(data2, colWidths=[4*cm, 12*cm])
t2.setStyle(TableStyle([
    ('FONTNAME', (0,0), (-1,0), 'Helvetica-Bold'),
    ('FONTSIZE', (0,0), (-1,-1), 9),
    ('BACKGROUND', (0,0), (-1,0), colors.HexColor('#2c5282')),
    ('TEXTCOLOR', (0,0), (-1,0), colors.white),
    ('BACKGROUND', (0,6), (-1,6), colors.HexColor('#2c5282')),
    ('TEXTCOLOR', (0,6), (-1,6), colors.white),
    ('FONTNAME', (0,6), (-1,6), 'Helvetica-Bold'),
    ('BACKGROUND', (0,11), (-1,11), colors.HexColor('#2c5282')),
    ('TEXTCOLOR', (0,11), (-1,11), colors.white),
    ('FONTNAME', (0,11), (-1,11), 'Helvetica-Bold'),
    ('GRID', (0,0), (-1,-1), 0.4, colors.grey),
    ('ROWBACKGROUNDS', (0,1), (-1,5), [colors.HexColor('#f0f4fa'), colors.white]),
    ('ROWBACKGROUNDS', (0,7), (-1,10), [colors.HexColor('#f0f4fa'), colors.white]),
    ('ROWBACKGROUNDS', (0,12), (-1,-1), [colors.HexColor('#f0f4fa'), colors.white]),
    ('TOPPADDING', (0,0), (-1,-1), 3),
    ('BOTTOMPADDING', (0,0), (-1,-1), 3),
]))
story.append(t2)
story.append(Spacer(1, 6))

story.append(Paragraph(
    "<b>Stage Grouping:</b> Stage I = T1N0M0; Stage IIA = T0-1N1 or T2N0; Stage IIB = T2N1 or T3N0; Stage IIIA = T3N1 or T0-3N2; Stage IIIB = T4 any N; Stage IIIC = any T N3; Stage IV = any T any N M1",
    body_style))

story.append(Paragraph("D. Types of Breast Cancer", sub_heading_style))
story.append(Paragraph("<b>Non-invasive (In Situ) Carcinoma:</b>", sub2_heading_style))
story.append(Paragraph("• <b>DCIS (Ductal Carcinoma In Situ):</b> Proliferation of malignant epithelial cells within ducts without basement membrane breach. Subtypes include comedo (central necrosis, calcification), cribriform, micropapillary, solid. Comedo subtype has highest grade and risk. Treated by wide local excision ± radiotherapy.", bullet_style))
story.append(Paragraph("• <b>LCIS (Lobular Carcinoma In Situ):</b> Proliferation within lobular units. Now reclassified as a risk marker rather than true malignancy (relative risk ×8–10). Bilateral risk. Managed conservatively with surveillance or chemoprevention.", bullet_style))

story.append(Paragraph("<b>Invasive (Infiltrating) Carcinoma:</b>", sub2_heading_style))
story.append(Paragraph("• <b>Invasive Ductal Carcinoma — No Special Type (IDC-NST):</b> 80% of all breast cancers. Variable grade (Nottingham grading system: tubule formation, nuclear pleomorphism, mitotic count). Presents as a hard, irregular, stellate mass.", bullet_style))
story.append(Paragraph("• <b>Invasive Lobular Carcinoma:</b> 10–15%. Classical form shows single-file (Indian file) pattern of cells. Bilateral in 10–15%. E-cadherin mutation characteristic.", bullet_style))
story.append(Paragraph("• <b>Medullary Carcinoma:</b> 5%. Well-circumscribed tumour with lymphocytic infiltrate, syncytial pattern, high grade. Better prognosis than IDC-NST despite high grade. Often ER-negative.", bullet_style))
story.append(Paragraph("• <b>Mucinous (Colloid) Carcinoma:</b> <2%. Pools of extracellular mucin surrounding tumour cells. Soft gelatinous mass. Better prognosis. Older women.", bullet_style))
story.append(Paragraph("• <b>Tubular Carcinoma:</b> <2%. Well-differentiated, angular tubules. Excellent prognosis. Usually ER+.", bullet_style))
story.append(Paragraph("• <b>Inflammatory Carcinoma:</b> <3%. Diffuse dermal lymphatic invasion causes erythema, peau d'orange, tenderness. T4d. Worst prognosis. Treated with neoadjuvant chemotherapy.", bullet_style))
story.append(Paragraph("• <b>Paget's Disease of the Nipple:</b> Intraepithelial spread of malignant cells (Paget cells) from underlying DCIS/IDC into nipple epidermis. Presents with eczematoid changes of nipple.", bullet_style))

story.append(Paragraph("Molecular Subtypes (Clinical Relevance):", sub2_heading_style))
data3 = [
    ['Subtype', 'Receptor Status', 'Prognosis', 'Treatment'],
    ['Luminal A', 'ER+/PR+, HER2−, Ki67 low', 'Best', 'Hormone therapy'],
    ['Luminal B', 'ER+/PR+, HER2± Ki67 high', 'Intermediate', 'Hormone ± chemo'],
    ['HER2-enriched', 'ER−PR−, HER2+', 'Aggressive', 'Trastuzumab + chemo'],
    ['Triple Negative', 'ER−PR−HER2−', 'Worst (BRCA1)', 'Chemo, PARP inhibitors'],
]
t3 = Table(data3, colWidths=[3.5*cm, 5.5*cm, 3*cm, 4*cm])
t3.setStyle(TableStyle([
    ('BACKGROUND', (0,0), (-1,0), colors.HexColor('#1a2744')),
    ('TEXTCOLOR', (0,0), (-1,0), colors.white),
    ('FONTNAME', (0,0), (-1,0), 'Helvetica-Bold'),
    ('FONTSIZE', (0,0), (-1,-1), 9),
    ('GRID', (0,0), (-1,-1), 0.4, colors.grey),
    ('ROWBACKGROUNDS', (0,1), (-1,-1), [colors.HexColor('#f0f4fa'), colors.white]),
    ('TOPPADDING', (0,0), (-1,-1), 3), ('BOTTOMPADDING', (0,0), (-1,-1), 3),
]))
story.append(t3)
story.append(Paragraph("<i>Reference: Bailey and Love's Short Practice of Surgery, 28th Ed; Pye's Surgical Handicraft, 22nd Ed</i>", ref_style))

# ══════════════════════════════════════════════════════════════════════════════
# Q3 — SHORT NOTES (5 x 4 = 20 marks)
# ══════════════════════════════════════════════════════════════════════════════
story.append(PageBreak())
story.append(Paragraph("Q3. Short Notes (5 Marks Each)", q_heading_style))

# 3a — Ormond's Disease
story.append(Paragraph("a) Ormond's Disease (Retroperitoneal Fibrosis)", sub_heading_style))
story.append(Paragraph(
    "Ormond's disease (idiopathic retroperitoneal fibrosis) is a rare fibro-inflammatory condition characterised by a dense fibrous plaque in the retroperitoneum, typically centred over the infrarenal aorta and iliac vessels, leading to encasement and obstruction of the ureters.",
    body_style))
story.append(Paragraph("<b>Pathology:</b> Dense fibrous tissue with chronic inflammatory infiltrate containing lymphocytes, plasma cells, and occasionally germinal centres. Over 70% are idiopathic (Ormond's disease); secondary causes include methysergide, ergot alkaloids, beta-blockers, aortic aneurysm, malignancy, tuberculosis, carcinoid.", bullet_style))
story.append(Paragraph("<b>Clinical Features:</b> Dull backache or flank pain, malaise, weight loss, lower limb oedema, hypertension. Bilateral ureteric obstruction leads to hydronephrosis and renal failure.", bullet_style))
story.append(Paragraph("<b>Investigations:</b> CT abdomen (periaortic soft tissue mass), MRI (characteristically low signal on T2 in fibrosis), IVU (bilateral hydronephrosis, medial deviation of ureters at L4-L5), elevated ESR, CRP.", bullet_style))
story.append(Paragraph("<b>Treatment:</b> Corticosteroids (prednisolone 40–60 mg/day, then taper) are first line. Tamoxifen used as steroid-sparing. Ureteric stents or nephrostomy for obstruction. Surgical ureterolysis with omental wrapping for refractory cases.", bullet_style))

# 3b — Short Bowel Syndrome
story.append(Paragraph("b) Short Bowel Syndrome", sub_heading_style))
story.append(Paragraph(
    "Short bowel syndrome (SBS) is the malabsorptive state resulting from functional or anatomical reduction of the small intestinal absorptive surface, typically defined as less than 200 cm of residual small bowel in adults (or <25% of expected length in children).",
    body_style))
story.append(Paragraph("<b>Causes:</b> Massive intestinal resection for Crohn's disease, mesenteric ischaemia (volvulus, thrombosis), radiation enteritis, trauma, neonatal necrotising enterocolitis.", bullet_style))
story.append(Paragraph("<b>Physiology:</b> Duodenum and proximal jejunum absorb carbohydrates, proteins, fat-soluble vitamins, iron, calcium. Ileum absorbs vitamin B12 (distal 50–60 cm) and bile salts (terminal ileum). Ileocaecal valve slows intestinal transit.", bullet_style))
story.append(Paragraph("<b>Clinical Features:</b> Profuse watery diarrhoea, steatorrhoea, dehydration, electrolyte disturbances (hyponatraemia, hypomagnesaemia), malnutrition, weight loss, metabolic acidosis (bicarbonate loss), oxalate nephrolithiasis.", bullet_style))
story.append(Paragraph("<b>Management:</b>", bullet_style))
story.append(Paragraph("  — Acute phase: Parenteral nutrition (TPN), fluid/electrolyte replacement, H2 blockers or PPIs (reduce hypergastrinaemia)", bullet_style))
story.append(Paragraph("  — Adaptation phase (3–6 months): Gradual enteral feeding, loperamide for diarrhoea, cholestyramine for bile salt diarrhoea", bullet_style))
story.append(Paragraph("  — Long-term: Teduglutide (GLP-2 analogue) promotes intestinal adaptation. Serial transverse enteroplasty (STEP) or Bianchi's intestinal lengthening procedure. Small bowel transplant in selected cases.", bullet_style))

# 3c — Ochsner-Sherren Regime
story.append(Paragraph("c) Ochsner-Sherren Regime", sub_heading_style))
story.append(Paragraph(
    "The Ochsner-Sherren (conservative) regime is a non-operative management strategy for appendicular mass (phlegmon) — a complication of acute appendicitis where the appendix becomes walled off by omentum and adjacent bowel, forming a palpable RIF mass.",
    body_style))
story.append(Paragraph("<b>Indication:</b> Palpable RIF mass presenting >72 hours after onset of symptoms in a stable, non-peritonitic patient.", bullet_style))
story.append(Paragraph("<b>Protocol:</b>", bullet_style))
story.append(Paragraph("  1. Admit and keep nil by mouth (or light diet)", bullet_style))
story.append(Paragraph("  2. IV antibiotics (cefuroxime + metronidazole, or piperacillin-tazobactam)", bullet_style))
story.append(Paragraph("  3. IV fluids and analgesia", bullet_style))
story.append(Paragraph("  4. Mark the mass margins on skin with a marker pen", bullet_style))
story.append(Paragraph("  5. Monitor 4-hourly: pulse, temperature, respirations and mass size", bullet_style))
story.append(Paragraph("<b>Indicators to Abandon and Operate (PAIRT):</b>", bullet_style))
story.append(Paragraph("  P — Pulse rising >100 bpm; A — Abdomen becoming generalised peritonitis; I — Increasing mass size; R — Rising temperature; T — Toxaemia worsening", bullet_style))
story.append(Paragraph("<b>Success:</b> Mass resolves in 3–6 weeks. Interval appendicectomy is done after 6–8 weeks. Colonoscopy in adults >40 years to exclude caecal carcinoma.", bullet_style))

# 3d — Pneumatosis Cystoides Intestinalis
story.append(Paragraph("d) Pneumatosis Cystoides Intestinalis", sub_heading_style))
story.append(Paragraph(
    "Pneumatosis cystoides intestinalis (PCI) is a rare condition characterised by the presence of multiple gas-filled cysts in the submucosa or subserosa of the bowel wall, most commonly affecting the small intestine and left colon.",
    body_style))
story.append(Paragraph("<b>Pathogenesis (Three Main Theories):</b>", bullet_style))
story.append(Paragraph("  1. <b>Mechanical theory:</b> Mucosal disruption allows intraluminal gas to dissect into the bowel wall along tissue planes.", bullet_style))
story.append(Paragraph("  2. <b>Bacterial theory:</b> Gas-producing bacteria (Clostridia, Bacteroides) invade the bowel wall, forming gas cysts.", bullet_style))
story.append(Paragraph("  3. <b>Pulmonary theory:</b> Alveolar rupture allows air to track along mediastinum → retroperitoneum → mesentery → bowel wall.", bullet_style))
story.append(Paragraph("<b>Clinical Features:</b> Often asymptomatic (incidental finding). May cause diarrhoea, bloating, rectal bleeding. Rarely: volvulus, bowel obstruction, pneumoperitoneum (benign, without peritonitis).", bullet_style))
story.append(Paragraph("<b>Associations:</b> COPD, steroid use, IBD, bowel obstruction, immunosuppression, neonatal NEC.", bullet_style))
story.append(Paragraph("<b>Diagnosis:</b> Abdominal X-ray (streaky/bubbly lucency in bowel wall), CT (confirmatory, also shows pneumoperitoneum without free fluid). Barium enema shows 'bunch of grapes' appearance.", bullet_style))
story.append(Paragraph("<b>Treatment:</b> Treat underlying cause. High-flow oxygen (>8 L/min) causes nitrogen washout and cyst regression. Antibiotics for bacterial form. Surgery for complications (obstruction, volvulus, significant bleeding).", bullet_style))
story.append(Paragraph("<i>Reference: Bailey and Love's Short Practice of Surgery, 28th Ed; Schwartz's Principles of Surgery, 11th Ed</i>", ref_style))

# ══════════════════════════════════════════════════════════════════════════════
# Q4 — CHOLEDOCHAL CYST (20 marks)
# ══════════════════════════════════════════════════════════════════════════════
story.append(PageBreak())
story.append(Paragraph("Q4. Choledochal Cyst — Theories, Todani Classification, and Management", q_heading_style))
story.append(Paragraph("[20 Marks]", mark_style))

story.append(Paragraph("A. Definition", sub_heading_style))
story.append(Paragraph(
    "Choledochal cysts are congenital cystic dilatations of the biliary tree (intrahepatic and/or extrahepatic bile ducts). They are rare (1:100,000–150,000 live births in Western populations; 1:1,000 in Asian populations). The female-to-male ratio is 4:1. Approximately 60% are diagnosed before age 10 years.",
    body_style))

story.append(Paragraph("B. Theories of Pathogenesis", sub_heading_style))
story.append(Paragraph(
    "Multiple theories have been proposed; the anomalous pancreaticobiliary ductal junction (APBDJ) is currently the most widely accepted.",
    body_style))
story.append(Paragraph("<b>1. Anomalous Pancreaticobiliary Junction (Babbitt's Theory — most accepted):</b> In APBDJ, the common channel between the pancreatic duct and bile duct is abnormally long (>15 mm outside the duodenal wall). This allows reflux of pancreatic enzymes (trypsinogen, amylase) into the bile duct, causing enzymatic inflammation and weakening of the ductal wall, leading to dilatation.", bullet_style))
story.append(Paragraph("<b>2. Primary Ductal Anomaly:</b> Unequal proliferation or vacuolation of bile duct epithelial cells during embryological development. In the 5th to 6th week, solid cord of cells canalises; unequal proliferation may cause localised weakness.", bullet_style))
story.append(Paragraph("<b>3. Distal Obstruction Theory:</b> Distal narrowing or stenosis of the bile duct leads to increased intraluminal pressure and proximal dilatation — a purely obstructive mechanism.", bullet_style))
story.append(Paragraph("<b>4. Autonomic Denervation Theory:</b> Absence of ganglion cells in the ductal wall (analogous to Hirschsprung's) causes aperistalsis and functional obstruction.", bullet_style))

story.append(Paragraph("C. Todani Classification of Choledochal Cysts", sub_heading_style))
data4 = [
    ['Type', 'Description', 'Frequency', 'Key Feature'],
    ['Type I (Most common ~80%)', 'Cystic/fusiform dilatation of the CBD', '80–90%', 'Extrahepatic; entire CBD or segment'],
    ['  Ia', 'Cystic dilatation of entire CBD', '', 'Most common subtype'],
    ['  Ib', 'Focal segmental dilatation of CBD', '', ''],
    ['  Ic', 'Fusiform/cylindrical dilatation', '', ''],
    ['Type II', 'True diverticulum of CBD', '<2%', 'Supraduodenal diverticulum'],
    ['Type III (Choledochocoele)', 'Intraduodenal cystic dilatation', '1–5%', 'Within duodenal wall; managed by endoscopy'],
    ['Type IV (2nd most common)', 'Multiple cysts', '15–20%', ''],
    ['  IVa', 'Intra + extrahepatic cysts', '', 'Roux-en-Y anastomosis; may need liver Tx'],
    ['  IVb', 'Multiple extrahepatic cysts only', '', ''],
    ['Type V (Caroli\'s Disease)', 'Multiple intrahepatic biliary cysts', 'Rare', 'Associated with polycystic kidney disease, cholangitis, cirrhosis'],
]
t4 = Table(data4, colWidths=[4.5*cm, 6*cm, 2.5*cm, 3*cm])
t4.setStyle(TableStyle([
    ('BACKGROUND', (0,0), (-1,0), colors.HexColor('#1a2744')),
    ('TEXTCOLOR', (0,0), (-1,0), colors.white),
    ('FONTNAME', (0,0), (-1,0), 'Helvetica-Bold'),
    ('FONTSIZE', (0,0), (-1,-1), 9),
    ('GRID', (0,0), (-1,-1), 0.4, colors.grey),
    ('ROWBACKGROUNDS', (0,1), (-1,-1), [colors.HexColor('#f0f4fa'), colors.white]),
    ('TOPPADDING', (0,0), (-1,-1), 3), ('BOTTOMPADDING', (0,0), (-1,-1), 3),
    ('VALIGN', (0,0), (-1,-1), 'TOP'),
]))
story.append(t4)
story.append(Spacer(1, 6))

story.append(Paragraph("D. Clinical Features", sub_heading_style))
story.append(Paragraph("The classical triad (present in only 10–20% of cases) consists of:", body_style))
story.append(Paragraph("1. Intermittent right upper quadrant/epigastric pain", bullet_style))
story.append(Paragraph("2. Obstructive jaundice", bullet_style))
story.append(Paragraph("3. Palpable RUQ mass", bullet_style))
story.append(Paragraph("Other features: Fever (cholangitis), pancreatitis (in adults), cholangiocarcinoma (2–15% lifetime risk — risk increases with age and with Types I, IV, V).", bullet_style))

story.append(Paragraph("E. Investigations", sub_heading_style))
story.append(Paragraph("• <b>Ultrasound (USG):</b> First-line investigation. Shows cystic dilatation of CBD. Confirms biliary nature.", bullet_style))
story.append(Paragraph("• <b>MRCP:</b> Investigation of choice. Delineates intrahepatic vs extrahepatic involvement, pancreaticobiliary junction anatomy, distal CBD. Non-invasive.", bullet_style))
story.append(Paragraph("• <b>CT abdomen:</b> Useful for extent of disease, associated liver pathology, and malignant transformation.", bullet_style))
story.append(Paragraph("• <b>ERCP:</b> Both diagnostic and therapeutic (for Type III). Shows APBDJ.", bullet_style))
story.append(Paragraph("• <b>LFTs, CA 19-9, CEA:</b> Elevated CA 19-9 may indicate malignant change.", bullet_style))

story.append(Paragraph("F. Management", sub_heading_style))
story.append(Paragraph("<b>Principles:</b> Complete excision of cyst is preferred over drainage procedures (which carry a risk of cholangitis and 5% rate of malignant transformation). Drainage procedures such as cystojejunostomy are now condemned.", body_style))
story.append(Paragraph("• <b>Type I and IV:</b> Complete cyst excision with Roux-en-Y hepaticojejunostomy (choledochojejunostomy). Laparoscopic approach is feasible. The biliary-enteric anastomosis is made to the hepatic ducts/common hepatic duct above the cyst.", bullet_style))
story.append(Paragraph("• <b>Type II:</b> Simple excision of diverticulum with primary CBD repair.", bullet_style))
story.append(Paragraph("• <b>Type III (Choledochocoele):</b> Endoscopic sphincterotomy. Open transduodenal excision if endoscopy fails. Biopsy of cyst wall to exclude dysplasia.", bullet_style))
story.append(Paragraph("• <b>Type IVa and V (Caroli's):</b> If localised to one lobe, hepatic resection. If bilobar, liver transplantation may be required.", bullet_style))
story.append(Paragraph("• <b>Malignant transformation:</b> If cholangiocarcinoma is suspected, proceed to extended resection (extended hepatectomy + biliary reconstruction).", bullet_style))
story.append(Paragraph("• <b>Follow-up:</b> Long-term surveillance with annual LFTs, CA 19-9, and MRCP/USG due to persistent risk of biliary malignancy even after excision.", bullet_style))
story.append(Paragraph("<i>Reference: Bailey and Love's Short Practice of Surgery 28th Ed; Sabiston Textbook of Surgery; Schwartz's Principles of Surgery, 11th Ed</i>", ref_style))

# ══════════════════════════════════════════════════════════════════════════════
# Q5 — SHORT NOTES (3 marks each)
# ══════════════════════════════════════════════════════════════════════════════
story.append(PageBreak())
story.append(Paragraph("Q5. Short Notes (3 Marks Each)", q_heading_style))

story.append(Paragraph("a) Meckel's Diverticulum and Diagnosis", sub_heading_style))
story.append(Paragraph(
    "Meckel's diverticulum (MD) is the most common congenital anomaly of the gastrointestinal tract, occurring in approximately 1.2–2% of the population. It is a true diverticulum — containing all three layers of bowel wall (mucosa, muscularis, and serosa). It results from incomplete obliteration of the vitello-intestinal (omphalomesenteric) duct.",
    body_style))
story.append(Paragraph("<b>Rule of 2s:</b> 2% incidence; 2 feet (60 cm) from ileocaecal valve on anti-mesenteric border; 2 cm long; 2:1 male predominance; 2% symptomatic; 2 types of ectopic mucosa (gastric, pancreatic).", bullet_style))
story.append(Paragraph("<b>Ectopic mucosa:</b> Gastric mucosa present in 50% (80–85% of all ectopic tissue); accounts for peptic ulceration and bleeding. Pancreatic tissue is second most common.", bullet_style))
story.append(Paragraph("<b>Complications:</b> Painless rectal bleeding (most common in children — maroon stools due to ectopic gastric mucosa ulceration), intestinal obstruction (intussusception, volvulus around fibrous cord), Meckel's diverticulitis (mimics appendicitis), umbilical fistula/sinus.", bullet_style))
story.append(Paragraph("<b>Diagnosis:</b>", bullet_style))
story.append(Paragraph("  1. <b>Meckel's Scan (99mTc pertechnetate scan):</b> Nuclear medicine scan of choice. 99mTc is taken up by ectopic gastric mucosa. Sensitivity 85–90% in children; 62% in adults.", bullet_style))
story.append(Paragraph("  2. <b>CT scan:</b> May show blind-ending tubular structure from anti-mesenteric border of terminal ileum. CT enterography improves detection.", bullet_style))
story.append(Paragraph("  3. <b>Capsule endoscopy:</b> Can visualise MD in bleeding cases.", bullet_style))
story.append(Paragraph("  4. <b>Angiography:</b> Active bleeding >0.5 mL/min.", bullet_style))
story.append(Paragraph("  5. <b>Laparoscopy/Exploratory laparotomy:</b> Definitive if suspected on clinical grounds.", bullet_style))
story.append(Paragraph("<b>Treatment:</b> Symptomatic MD: diverticulectomy (wedge resection) or ileal segmental resection (when base is wide or when base ulceration is present).", bullet_style))

story.append(Paragraph("b) Imaging Modalities in Blunt Trauma Abdomen", sub_heading_style))
story.append(Paragraph(
    "Blunt abdominal trauma requires rapid, systematic evaluation to detect solid organ injury, hollow viscus perforation, and vascular injury in the haemodynamically stable or unstable patient.",
    body_style))
story.append(Paragraph("<b>FAST (Focused Assessment with Sonography in Trauma):</b>", bullet_style))
story.append(Paragraph("  — The initial imaging tool of choice in unstable patients. Detects free fluid (blood) in peritoneal and pericardial spaces. Views: hepatorenal (Morrison's pouch), splenorenal, pelvic (pouch of Douglas), pericardial. Sensitivity 63–100% for haemoperitoneum.", bullet_style))
story.append(Paragraph("  — e-FAST (Extended FAST) adds pneumothorax assessment (bilateral anterior chest).", bullet_style))
story.append(Paragraph("<b>CT Abdomen and Pelvis (with IV contrast):</b>", bullet_style))
story.append(Paragraph("  — Gold standard for haemodynamically stable patients. Sensitivity >95% for solid organ injuries. Grades splenic, hepatic, and renal injuries (AAST organ injury scale, I–V). Identifies active contrast blush (ongoing arterial bleeding, mandating IR or surgery). Identifies retroperitoneal haematoma, bowel wall thickening, free air, mesenteric injury.", bullet_style))
story.append(Paragraph("<b>Diagnostic Peritoneal Lavage (DPL):</b>", bullet_style))
story.append(Paragraph("  — Historically the standard. Now largely replaced by FAST + CT. Positive if >100,000 RBC/μL (blunt), >500 WBC/μL, or bile/bowel contents on aspirate. 98% sensitive but non-specific and invasive.", bullet_style))
story.append(Paragraph("<b>Plain Abdominal X-ray:</b> Limited utility. May show pneumoperitoneum (upright CXR), fractures (pelvis, lower ribs), or retained foreign bodies.", bullet_style))
story.append(Paragraph("<b>Angiography:</b> Used for embolisation of solid organ bleeding (splenic, hepatic, renal) after CT identification of arterial blush.", bullet_style))
story.append(Paragraph("<b>MRI:</b> Not used in acute trauma; occasionally useful for delayed assessment of diaphragmatic, spinal, or soft tissue injuries.", bullet_style))
story.append(Paragraph("<i>Reference: Rosen's Emergency Medicine; Fischer's Mastery of Surgery, 8th Ed; Schwartz's Principles of Surgery</i>", ref_style))

# ══════════════════════════════════════════════════════════════════════════════
# Q6 — SHORT NOTES (5 x 2 = 10 marks)
# ══════════════════════════════════════════════════════════════════════════════
story.append(PageBreak())
story.append(Paragraph("Q6. Short Notes (5 Marks Each)", q_heading_style))

story.append(Paragraph("A) Non-Union: Etiology, Classification, and Management", sub_heading_style))
story.append(Paragraph(
    "Non-union is defined as cessation of all reparative processes of fracture healing without achieving bony union, typically declared when no healing is seen for three or more consecutive months (most authorities define non-union at 6–9 months after injury, depending on fracture site).",
    body_style))
story.append(Paragraph("<b>Aetiology (Factors Impairing Healing):</b>", bullet_style))
story.append(Paragraph("  <b>Patient factors:</b> Malnutrition, osteoporosis, diabetes mellitus, peripheral vascular disease, corticosteroid use, NSAIDs (inhibit prostaglandin-mediated healing), hypothyroidism, smoking (vasoconstriction).", bullet_style))
story.append(Paragraph("  <b>Fracture factors:</b> Inadequate blood supply (femoral neck, scaphoid waist, distal tibia), high-energy/comminuted fractures, pathological fractures, open/infected fractures, severe soft tissue damage.", bullet_style))
story.append(Paragraph("  <b>Treatment factors:</b> Inadequate immobilisation, excessive distraction, poor reduction, premature weight-bearing, infection at fracture site.", bullet_style))
story.append(Paragraph("<b>Classification:</b>", bullet_style))
story.append(Paragraph("  <b>1. Weber-Cech Classification (biological activity):</b>", bullet_style))
story.append(Paragraph("    • <b>Hypertrophic non-union</b> (biologically active, mechanically inadequate): Adequate vascularity but excessive movement. X-ray shows 'elephant foot' (abundant callus). Treatment: stabilisation only.", bullet_style))
story.append(Paragraph("    • <b>Oligotrophic non-union:</b> Little callus, moderate vascularity. Treatment: improve vascularity + stabilisation.", bullet_style))
story.append(Paragraph("    • <b>Atrophic non-union</b> (biologically inactive): Avascular — 'horse's hoof' or 'dystrophic' patterns. No callus. Treatment: bone grafting + stabilisation.", bullet_style))
story.append(Paragraph("  <b>2. Infected non-union:</b> Presence of infection significantly alters management — requires débridement, antibiotic treatment, and staged reconstruction.", bullet_style))
story.append(Paragraph("<b>Investigations:</b> X-rays (AP + lateral, oblique views), CT scan (defines bone defect, synovial pseudarthrosis), MRI (bone marrow oedema, soft tissue), isotope bone scan, infection markers (ESR, CRP, WBC), culture from sinus tract.", bullet_style))
story.append(Paragraph("<b>Management:</b>", bullet_style))
story.append(Paragraph("  1. <b>Treat underlying infection</b> if present: Débridement, systemic antibiotics", bullet_style))
story.append(Paragraph("  2. <b>Improve vascularity</b>: Periosteal stripping, multiple drill holes (Phemister), bone grafting (autograft from iliac crest is gold standard)", bullet_style))
story.append(Paragraph("  3. <b>Stabilisation</b>: Intramedullary nailing (preferred), external fixation (infected cases), plate-and-screw fixation", bullet_style))
story.append(Paragraph("  4. <b>Biological augmentation</b>: BMP-2 or BMP-7 (recombinant bone morphogenetic proteins), demineralised bone matrix, platelet-rich plasma", bullet_style))
story.append(Paragraph("  5. <b>Electrical stimulation</b>: Pulsed electromagnetic fields (PEMF) or direct current stimulation for oligotrophic/atrophic cases", bullet_style))
story.append(Paragraph("  6. <b>Bone transport</b> (Ilizarov technique): For bone defects >2–3 cm", bullet_style))

story.append(Paragraph("B) Myositis Ossificans", sub_heading_style))
story.append(Paragraph(
    "Myositis ossificans (MO) is a benign, self-limiting condition characterised by heterotopic bone (ectopic ossification) formation within muscle or soft tissue, usually following trauma. It is distinct from myositis ossificans progressiva (fibrodysplasia ossificans progressiva), which is a rare genetic disorder.",
    body_style))
story.append(Paragraph("<b>Types:</b>", bullet_style))
story.append(Paragraph("  1. <b>Myositis ossificans traumatica:</b> Most common. Follows direct muscle contusion (e.g., quadriceps, brachialis after elbow dislocation).", bullet_style))
story.append(Paragraph("  2. <b>Myositis ossificans circumscripta:</b> Localised non-traumatic form.", bullet_style))
story.append(Paragraph("  3. <b>Myositis ossificans progressiva:</b> Autosomal dominant, FOP gene (ACVR1 mutation), progressive heterotopic ossification of muscles, tendons, fascia from childhood onward.", bullet_style))
story.append(Paragraph("<b>Pathogenesis:</b> Mesenchymal stem cells undergo aberrant osteoblastic differentiation. 'Zonal phenomenon' is characteristic: central zone of immature, undifferentiated cells; intermediate zone of osteoid; peripheral zone of mature lamellar bone (the reverse of sarcoma).", bullet_style))
story.append(Paragraph("<b>Clinical Features:</b> Painful, firm soft-tissue swelling after trauma. Gradually becomes hard and bony over 4–6 weeks. Functional limitation (especially elbow and hip). May restrict range of motion.", bullet_style))
story.append(Paragraph("<b>Investigations:</b>", bullet_style))
story.append(Paragraph("  — X-ray: Initially soft tissue density; peripheral calcification by 3–4 weeks; mature shell of bone by 6–8 weeks (peripheral ossification = key diagnostic feature, distinguishes from osteosarcoma which has central ossification).", bullet_style))
story.append(Paragraph("  — CT: Shows zonal pattern clearly.", bullet_style))
story.append(Paragraph("  — MRI: Bone marrow oedema pattern initially; mature bone later. Not always helpful early.", bullet_style))
story.append(Paragraph("  — Bone scan: Hot spot in early phases; decreases as lesion matures.", bullet_style))
story.append(Paragraph("  — Serum alkaline phosphatase: Raised in active phase.", bullet_style))
story.append(Paragraph("<b>Management:</b> Conservative initially — rest, NSAIDs (indomethacin), ice, gentle stretching. Radiation therapy (single dose 7–8 Gy) as prophylaxis in high-risk cases. Surgical excision only after maturation (12–18 months, confirmed by serial X-rays and normalised ALP) — early excision causes recurrence.", bullet_style))
story.append(Paragraph("<i>Reference: Schwartz's Principles of Surgery; Campbell's Operative Orthopaedics</i>", ref_style))

# ══════════════════════════════════════════════════════════════════════════════
# Q7 — LOCAL ANAESTHETICS (10 marks)
# ══════════════════════════════════════════════════════════════════════════════
story.append(PageBreak())
story.append(Paragraph("Q7. Local Anaesthetics (10 Marks)", q_heading_style))
story.append(Paragraph("[a) Classification and Pharmacology — 4 marks; b) Mechanism of Action — 3 marks; c) Systemic Toxicity and Management — 3 marks]", mark_style))

story.append(Paragraph("a) Classification and Pharmacology of Local Anaesthetics", sub_heading_style))
story.append(Paragraph(
    "Local anaesthetics are drugs that reversibly block peripheral nerve conduction by inhibiting sodium channels, producing local or regional anaesthesia without loss of consciousness.",
    body_style))
story.append(Paragraph("<b>Chemical Classification:</b>", bullet_style))
data5 = [
    ['Class', 'Examples', 'Key Properties'],
    ['Amides (—NH—CO—)', 'Lidocaine, Bupivacaine,\nRopivacaine, Levobupivacaine,\nPrilocaine, Mepivacaine', 'Metabolised in liver (CYP enzymes). More stable. No cross-reactivity with esters. "Amide" contains an "i" before the suffix: lIdocaine, bupIvacaine'],
    ['Esters (—O—CO—)', 'Procaine, Cocaine,\nTetracaine, Benzocaine,\nChloroprocaine', 'Hydrolysed by plasma pseudocholinesterase (PABA metabolite — potential allergen). Less stable. Shorter shelf life. Cause more allergic reactions'],
]
t5 = Table(data5, colWidths=[4.5*cm, 5.5*cm, 6*cm])
t5.setStyle(TableStyle([
    ('BACKGROUND', (0,0), (-1,0), colors.HexColor('#1a2744')),
    ('TEXTCOLOR', (0,0), (-1,0), colors.white),
    ('FONTNAME', (0,0), (-1,0), 'Helvetica-Bold'),
    ('FONTSIZE', (0,0), (-1,-1), 9),
    ('GRID', (0,0), (-1,-1), 0.4, colors.grey),
    ('ROWBACKGROUNDS', (0,1), (-1,-1), [colors.HexColor('#f0f4fa'), colors.white]),
    ('TOPPADDING', (0,0), (-1,-1), 4), ('BOTTOMPADDING', (0,0), (-1,-1), 4),
    ('VALIGN', (0,0), (-1,-1), 'TOP'),
]))
story.append(t5)
story.append(Spacer(1, 6))

story.append(Paragraph("<b>Classification by Duration of Action:</b>", bullet_style))
data6 = [
    ['Duration', 'Agents', 'Approximate Duration (without epi)'],
    ['Short', 'Procaine, Chloroprocaine', '30–60 min'],
    ['Intermediate', 'Lidocaine, Mepivacaine, Prilocaine', '1–2 hours'],
    ['Long', 'Bupivacaine, Ropivacaine, Tetracaine', '4–8 hours'],
]
t6 = Table(data6, colWidths=[3*cm, 6*cm, 7*cm])
t6.setStyle(TableStyle([
    ('BACKGROUND', (0,0), (-1,0), colors.HexColor('#2c5282')),
    ('TEXTCOLOR', (0,0), (-1,0), colors.white),
    ('FONTNAME', (0,0), (-1,0), 'Helvetica-Bold'),
    ('FONTSIZE', (0,0), (-1,-1), 9),
    ('GRID', (0,0), (-1,-1), 0.4, colors.grey),
    ('ROWBACKGROUNDS', (0,1), (-1,-1), [colors.HexColor('#f0f4fa'), colors.white]),
    ('TOPPADDING', (0,0), (-1,-1), 3), ('BOTTOMPADDING', (0,0), (-1,-1), 3),
]))
story.append(t6)
story.append(Spacer(1, 5))

story.append(Paragraph("<b>Pharmacological Properties:</b>", bullet_style))
story.append(Paragraph("  — <b>pKa:</b> Determines onset. Agents with pKa near physiological pH (7.4) have faster onset (more unionised form crosses nerve membrane). Lidocaine pKa 7.9; Bupivacaine pKa 8.1.", bullet_style))
story.append(Paragraph("  — <b>Lipid solubility:</b> Determines potency (bupivacaine > lidocaine > procaine).", bullet_style))
story.append(Paragraph("  — <b>Protein binding:</b> Determines duration (bupivacaine 96% protein bound → long duration; procaine 6% → short).", bullet_style))
story.append(Paragraph("  — <b>Vasodilatory effect:</b> All except cocaine cause vasodilation; cocaine causes vasoconstriction (blocks norepinephrine reuptake).", bullet_style))
story.append(Paragraph("  — <b>Epinephrine additives:</b> 1:200,000 epinephrine reduces systemic absorption, prolongs duration by 50%, reduces bleeding. Contraindicated in end-arteries (digits, nose, penis).", bullet_style))

story.append(Paragraph("b) Mechanism of Action", sub_heading_style))
story.append(Paragraph(
    "Local anaesthetics act by blocking voltage-gated sodium (Na+) channels in the axonal membrane, preventing the generation and propagation of action potentials.",
    body_style))
story.append(Paragraph("<b>Molecular Mechanism:</b>", bullet_style))
story.append(Paragraph("  1. Local anaesthetic molecules (weak bases) exist in equilibrium between ionised (BH+) and unionised (B) forms depending on pH.", bullet_style))
story.append(Paragraph("  2. The unionised lipophilic form crosses the phospholipid nerve membrane.", bullet_style))
story.append(Paragraph("  3. Inside the axon, the drug re-ionises (lower intracellular pH) and the charged cationic form (BH+) binds to the intracellular aspect of the voltage-gated Na+ channel at the S6 transmembrane segment (DI-IV).", bullet_style))
story.append(Paragraph("  4. The channel is stabilised in the inactivated (closed) state — preventing sodium influx required for depolarisation.", bullet_style))
story.append(Paragraph("  5. <b>Use-dependence (frequency-dependence):</b> Repeated channel opening (rapidly firing axons) leads to greater accumulation of drug. High-frequency sensory pain fibres are blocked preferentially over motor fibres.", bullet_style))
story.append(Paragraph("<b>Differential Nerve Blockade:</b> Small, unmyelinated C-fibres (pain, temperature, autonomic) are blocked first, followed by myelinated Aδ (sharp pain), then Aβ (touch), and finally Aα (motor). Sequence of loss: pain → temperature → touch → proprioception → motor.", bullet_style))
story.append(Paragraph("<b>Notable Exception:</b> Benzocaine acts by membrane expansion (lipid solubility) rather than channel binding — lacks the ionisable amine group.", bullet_style))

story.append(Paragraph("c) Systemic Toxicity and Management", sub_heading_style))
story.append(Paragraph(
    "Local anaesthetic systemic toxicity (LAST) is a life-threatening complication from excessive plasma concentrations, most often from inadvertent intravascular injection, rapid absorption from highly vascular sites, or total dose excess.",
    body_style))
story.append(Paragraph("<b>CNS Toxicity (occurs at lower blood levels — CNS is more sensitive):</b>", bullet_style))
story.append(Paragraph("  <b>Early excitatory symptoms:</b> Perioral tingling/numbness, metallic taste, tinnitus, light-headedness, visual disturbances, agitation, tremors.", bullet_style))
story.append(Paragraph("  <b>Later inhibitory phase:</b> Generalised seizures (inhibition of inhibitory interneurons) → CNS depression → respiratory arrest.", bullet_style))
story.append(Paragraph("<b>Cardiovascular Toxicity (occurs at higher levels):</b>", bullet_style))
story.append(Paragraph("  — Na+ channel blockade → slowed conduction → widened QRS, prolonged PR, Heart block.", bullet_style))
story.append(Paragraph("  — K+ and Ca2+ channel blockade → negative inotropy and chronotropy.", bullet_style))
story.append(Paragraph("  — <b>Bupivacaine cardiotoxicity:</b> Extremely potent; binds K+ channels in addition → ventricular fibrillation, resistant cardiac arrest (the 'R' on T phenomenon).", bullet_style))
story.append(Paragraph("  — Hypotension, bradycardia, VT/VF, cardiac arrest.", bullet_style))

story.append(Paragraph("<b>Risk Factors for LAST:</b> High total dose, highly vascular injection site (intercostal > epidural > brachial plexus > subcutaneous), extremes of age, low lean body mass, liver disease, cardiac disease.", bullet_style))
story.append(Paragraph("<b>Management of LAST (AAGBI Guidelines):</b>", bullet_style))
story.append(Paragraph("  1. <b>Stop injection immediately</b> and call for help", bullet_style))
story.append(Paragraph("  2. <b>Airway management:</b> 100% oxygen, intubation if necessary — prevent hypoxia and acidosis (which worsen toxicity)", bullet_style))
story.append(Paragraph("  3. <b>Seizure control:</b> Benzodiazepines (midazolam, diazepam); avoid propofol in high doses (itself cardiotoxic)", bullet_style))
story.append(Paragraph("  4. <b>Cardiovascular support:</b> IV fluids, vasopressors (adrenaline in small doses — 1 mcg/kg); avoid calcium channel blockers and β-blockers", bullet_style))
story.append(Paragraph("  5. <b>Intralipid (20% lipid emulsion) — Lipid Rescue:</b>", bullet_style))
story.append(Paragraph("      — Bolus: 1.5 mL/kg IV over 1 min; infusion 0.25 mL/kg/min", bullet_style))
story.append(Paragraph("      — Mechanism: 'Lipid sink' — sequesters lipophilic LA molecules from cardiac tissue", bullet_style))
story.append(Paragraph("      — Max dose: 12 mL/kg", bullet_style))
story.append(Paragraph("  6. <b>CPR</b> if cardiac arrest — prolonged (up to 60 min) as lipid rescue may restore spontaneous rhythm", bullet_style))
story.append(Paragraph("  7. <b>ECMO/CPB:</b> Consider in refractory bupivacaine-induced cardiac arrest", bullet_style))
story.append(Paragraph("<i>Reference: Miller's Anesthesia, 10th Ed; Rosen's Emergency Medicine, 10th Ed</i>", ref_style))

# ══════════════════════════════════════════════════════════════════════════════
# Q8 — PANCREATIC TRAUMA (4 marks)
# ══════════════════════════════════════════════════════════════════════════════
story.append(PageBreak())
story.append(Paragraph("Q8. Pancreatic Trauma", q_heading_style))
story.append(Paragraph("[4 Marks]", mark_style))

story.append(Paragraph("Introduction", sub_heading_style))
story.append(Paragraph(
    "Pancreatic trauma is uncommon, occurring in 2% of patients after stab wounds, 5–6% after blunt abdominal trauma, and 6% after gunshot wounds to the abdomen (Fischer's Mastery of Surgery). It is associated with high mortality (10–25%) due to associated injuries and delayed diagnosis.",
    body_style))

story.append(Paragraph("Mechanism", sub_heading_style))
story.append(Paragraph("• <b>Blunt trauma:</b> Direct epigastric blow compresses the pancreatic body/neck against the vertebral column (most commonly L1–L2). Classic mechanism — handlebar injury in cyclists (Handlebar syndrome), steering wheel injuries. Associated injuries: duodenum, liver, spleen, major vessels.", bullet_style))
story.append(Paragraph("• <b>Penetrating trauma:</b> Stab wounds or gunshot wounds. Head injuries associated with IVC, right renal vessels; neck/uncinate injuries with SMA/SMV/portal vein; tail injuries with spleen, splenic vessels.", bullet_style))

story.append(Paragraph("AAST Organ Injury Scale for Pancreas (Grade I–V)", sub_heading_style))
data7 = [
    ['Grade', 'Injury Description', 'Treatment Principle'],
    ['I', 'Minor contusion/laceration, no duct injury', 'Drainage only'],
    ['II', 'Major contusion/laceration, no duct injury, no tissue loss', 'Drainage'],
    ['III', 'Distal transection or parenchymal injury with duct injury', 'Distal pancreatectomy ± splenectomy'],
    ['IV', 'Proximal transection (right of SMA) or parenchymal injury involving ampulla', 'Pancreatoduodenectomy (Whipple) or complex repair'],
    ['V', 'Massive disruption of pancreatic head', 'Damage control; staged Whipple'],
]
t7 = Table(data7, colWidths=[1.5*cm, 7.5*cm, 7*cm])
t7.setStyle(TableStyle([
    ('BACKGROUND', (0,0), (-1,0), colors.HexColor('#1a2744')),
    ('TEXTCOLOR', (0,0), (-1,0), colors.white),
    ('FONTNAME', (0,0), (-1,0), 'Helvetica-Bold'),
    ('FONTSIZE', (0,0), (-1,-1), 9),
    ('GRID', (0,0), (-1,-1), 0.4, colors.grey),
    ('ROWBACKGROUNDS', (0,1), (-1,-1), [colors.HexColor('#f0f4fa'), colors.white]),
    ('TOPPADDING', (0,0), (-1,-1), 4), ('BOTTOMPADDING', (0,0), (-1,-1), 4),
    ('VALIGN', (0,0), (-1,-1), 'TOP'),
]))
story.append(t7)
story.append(Spacer(1, 6))

story.append(Paragraph("Diagnosis", sub_heading_style))
story.append(Paragraph("• <b>Serum amylase:</b> Elevated in 80% initially; may be normal early (normal amylase does not exclude pancreatic injury). Rises within 3–6 hours.", bullet_style))
story.append(Paragraph("• <b>CT abdomen with contrast (gold standard):</b> Identifies parenchymal contusion, haematoma, laceration, and peripancreatic fluid. However, early post-injury CT may underestimate ductal injury — accuracy improves at 12–24 hours.", bullet_style))
story.append(Paragraph("• <b>MRCP:</b> Non-invasive assessment of pancreatic duct integrity in stable patients.", bullet_style))
story.append(Paragraph("• <b>ERCP:</b> Both diagnostic and therapeutic — stenting of disrupted main pancreatic duct.", bullet_style))

story.append(Paragraph("Management", sub_heading_style))
story.append(Paragraph("• <b>Non-operative management:</b> Grades I–II without main duct injury, haemodynamically stable. Bowel rest, TPN or jejunal tube feeds, serial imaging. Drain peripancreatic collections percutaneously.", bullet_style))
story.append(Paragraph("• <b>Operative management:</b> Haemodynamic instability, peritonitis, ductal injury on imaging.", bullet_style))
story.append(Paragraph("  — Grade III: Distal pancreatectomy with or without spleen preservation (splenic vessel-preserving technique). Main duct injury distal to SMA is addressed by resection.", bullet_style))
story.append(Paragraph("  — Grade IV–V: Complex injuries may require staged damage control (haemostasis + external drainage), followed by reconstruction (Whipple/pancreatoduodenectomy).", bullet_style))
story.append(Paragraph("• <b>Complications:</b> Pancreatic fistula (most common — 10–35%), pseudocyst, abscess, pancreatitis, post-pancreatectomy haemorrhage.", bullet_style))
story.append(Paragraph("<i>Reference: Fischer's Mastery of Surgery, 8th Ed; Schwartz's Principles of Surgery, 11th Ed; Bailey and Love's Short Practice of Surgery, 28th Ed</i>", ref_style))

# ─── FOOTER ──────────────────────────────────────────────────────────────────
story.append(Spacer(1, 15))
story.append(HRFlowable(width="100%", thickness=1, color=colors.HexColor('#1a2744')))
story.append(Paragraph(
    "References: Bailey and Love's Short Practice of Surgery (28th Ed) | Schwartz's Principles of Surgery (11th Ed) | Fischer's Mastery of Surgery (8th Ed) | Miller's Anesthesia (10th Ed) | Sleisenger & Fordtran's Gastrointestinal and Liver Disease | Sabiston Textbook of Surgery | Rosen's Emergency Medicine (10th Ed)",
    ref_style))

doc.build(story)
print("PDF created successfully!")