from reportlab.lib.pagesizes import letter
from reportlab.lib import colors
from reportlab.lib.units import inch
from reportlab.platypus import (
    SimpleDocTemplate, Paragraph, Spacer, Table, TableStyle,
    HRFlowable
)
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.enums import TA_CENTER, TA_LEFT
from reportlab.platypus import KeepTogether

OUTPUT = "/home/daytona/workspace/cpr-guide/CPR_Quick_Reference.pdf"

# ── Colours ───────────────────────────────────────────────────────────────────
RED       = colors.HexColor("#CC1F1A")
DARK_RED  = colors.HexColor("#8B0000")
LIGHT_RED = colors.HexColor("#FDECEA")
DARK_GRAY = colors.HexColor("#2B2B2B")
MID_GRAY  = colors.HexColor("#555555")
LIGHT_GRAY= colors.HexColor("#F4F4F4")
WHITE     = colors.white
TEAL      = colors.HexColor("#0B6E7C")

# ── Document ──────────────────────────────────────────────────────────────────
doc = SimpleDocTemplate(
    OUTPUT,
    pagesize=letter,
    leftMargin=0.6*inch,
    rightMargin=0.6*inch,
    topMargin=0.5*inch,
    bottomMargin=0.5*inch,
)

styles = getSampleStyleSheet()

# Custom styles
title_style = ParagraphStyle(
    "Title", fontSize=26, fontName="Helvetica-Bold",
    textColor=WHITE, alignment=TA_CENTER, spaceAfter=2
)
subtitle_style = ParagraphStyle(
    "Subtitle", fontSize=11, fontName="Helvetica",
    textColor=WHITE, alignment=TA_CENTER, spaceAfter=0
)
section_header = ParagraphStyle(
    "SectionHeader", fontSize=12, fontName="Helvetica-Bold",
    textColor=WHITE, alignment=TA_LEFT, leftIndent=6, spaceAfter=0
)
step_num_style = ParagraphStyle(
    "StepNum", fontSize=18, fontName="Helvetica-Bold",
    textColor=WHITE, alignment=TA_CENTER
)
step_title_style = ParagraphStyle(
    "StepTitle", fontSize=12, fontName="Helvetica-Bold",
    textColor=DARK_RED, spaceAfter=2
)
step_body_style = ParagraphStyle(
    "StepBody", fontSize=9.5, fontName="Helvetica",
    textColor=DARK_GRAY, leading=14, spaceAfter=0
)
note_style = ParagraphStyle(
    "Note", fontSize=8.5, fontName="Helvetica-Oblique",
    textColor=MID_GRAY, leading=12
)
key_num_style = ParagraphStyle(
    "KeyNum", fontSize=22, fontName="Helvetica-Bold",
    textColor=RED, alignment=TA_CENTER
)
key_label_style = ParagraphStyle(
    "KeyLabel", fontSize=8, fontName="Helvetica",
    textColor=MID_GRAY, alignment=TA_CENTER
)
footer_style = ParagraphStyle(
    "Footer", fontSize=7.5, fontName="Helvetica",
    textColor=MID_GRAY, alignment=TA_CENTER
)

story = []

# ── HEADER BANNER ─────────────────────────────────────────────────────────────
header_data = [[
    Paragraph("❤  CPR QUICK REFERENCE GUIDE", title_style),
    Paragraph("Adult Cardiopulmonary Resuscitation  |  AHA / Red Cross Guidelines 2025", subtitle_style),
]]
header_table = Table(header_data, colWidths=[7.3*inch])
header_table.setStyle(TableStyle([
    ("BACKGROUND",  (0,0), (-1,-1), RED),
    ("ROUNDEDCORNERS", [8]),
    ("TOPPADDING",  (0,0), (-1,-1), 10),
    ("BOTTOMPADDING",(0,0),(-1,-1), 10),
    ("LEFTPADDING", (0,0), (-1,-1), 14),
    ("RIGHTPADDING",(0,0), (-1,-1), 14),
    ("VALIGN",      (0,0), (-1,-1), "MIDDLE"),
]))
story.append(header_table)
story.append(Spacer(1, 10))

# ── EMERGENCY CALLOUT ─────────────────────────────────────────────────────────
callout_data = [[
    Paragraph("☎  CALL 911 FIRST (or direct a bystander to call) — then begin CPR", ParagraphStyle(
        "Callout", fontSize=11, fontName="Helvetica-Bold",
        textColor=DARK_RED, alignment=TA_CENTER
    ))
]]
callout_table = Table(callout_data, colWidths=[7.3*inch])
callout_table.setStyle(TableStyle([
    ("BACKGROUND",  (0,0),(-1,-1), LIGHT_RED),
    ("BOX",         (0,0),(-1,-1), 1.5, RED),
    ("ROUNDEDCORNERS",[6]),
    ("TOPPADDING",  (0,0),(-1,-1), 8),
    ("BOTTOMPADDING",(0,0),(-1,-1), 8),
]))
story.append(callout_table)
story.append(Spacer(1, 10))

# ── STEPS ─────────────────────────────────────────────────────────────────────
steps = [
    ("1", "CHECK THE SCENE",
     "Ensure the environment is safe. Use gloves or PPE if available."),
    ("2", "CHECK FOR RESPONSIVENESS",
     "Tap shoulders firmly. Shout 'Are you okay?' twice.\nIf no response and not breathing normally → proceed."),
    ("3", "CALL 911 & GET AN AED",
     "Call 911 or send someone to call. Send a second person\nto retrieve an AED from the nearest location."),
    ("4", "POSITION THE PERSON",
     "Place them on their back on a firm, flat surface.\nKneel beside their chest."),
    ("5", "30 CHEST COMPRESSIONS",
     "• Heel of hand on center of chest (lower sternum)\n• Second hand on top, fingers interlaced\n• Arms straight, lean directly over hands\n• Compress ≥ 2 inches deep at 100–120/min\n• Allow full chest recoil between compressions"),
    ("6", "OPEN THE AIRWAY",
     "Head-tilt / chin-lift:\n• One hand on forehead, tilt back gently\n• Two fingers under chin, lift upward"),
    ("7", "2 RESCUE BREATHS",
     "• Pinch nose shut, seal mouth completely\n• Give 1 breath over 1 second — watch chest rise\n• If chest does not rise, retilt head and retry once"),
    ("8", "REPEAT 30:2 CYCLE",
     "Continue sets of 30 compressions + 2 breaths.\nMinimize any pause to < 10 seconds."),
    ("9", "USE AED WHEN AVAILABLE",
     "Power on AED → attach pads as shown → follow voice prompts.\nDeliver shock if advised, then immediately resume CPR."),
    ("10","KEEP GOING",
     "Stop only when:\n• Person shows clear signs of life\n• Trained EMS takes over\n• You are physically unable to continue"),
]

# Build steps as a 2-column grid: 5 rows × 2 cols
def make_step_cell(num, title, body):
    num_table = Table([[Paragraph(num, step_num_style)]], colWidths=[0.42*inch])
    num_table.setStyle(TableStyle([
        ("BACKGROUND",  (0,0),(-1,-1), RED),
        ("ROUNDEDCORNERS",[20]),
        ("TOPPADDING",  (0,0),(-1,-1), 5),
        ("BOTTOMPADDING",(0,0),(-1,-1), 5),
    ]))
    text_block = [
        Paragraph(title, step_title_style),
        Paragraph(body.replace("\n", "<br/>"), step_body_style),
    ]
    inner = Table(
        [[num_table, [Paragraph(title, step_title_style),
                      Paragraph(body.replace("\n","<br/>"), step_body_style)]]],
        colWidths=[0.48*inch, 3.0*inch]
    )
    inner.setStyle(TableStyle([
        ("VALIGN",      (0,0),(-1,-1), "TOP"),
        ("LEFTPADDING", (0,0),(0,-1), 0),
        ("RIGHTPADDING",(0,0),(0,-1), 6),
        ("LEFTPADDING", (1,0),(1,-1), 4),
        ("TOPPADDING",  (0,0),(-1,-1), 0),
        ("BOTTOMPADDING",(0,0),(-1,-1), 0),
    ]))
    wrapper = Table([[inner]], colWidths=[3.6*inch])
    wrapper.setStyle(TableStyle([
        ("BACKGROUND",  (0,0),(-1,-1), LIGHT_GRAY),
        ("BOX",         (0,0),(-1,-1), 0.5, colors.HexColor("#DDDDDD")),
        ("ROUNDEDCORNERS",[6]),
        ("TOPPADDING",  (0,0),(-1,-1), 8),
        ("BOTTOMPADDING",(0,0),(-1,-1), 8),
        ("LEFTPADDING", (0,0),(-1,-1), 8),
        ("RIGHTPADDING",(0,0),(-1,-1), 8),
    ]))
    return wrapper

# Pair steps into rows of 2
step_rows = []
for i in range(0, len(steps), 2):
    left  = make_step_cell(*steps[i])
    right = make_step_cell(*steps[i+1]) if i+1 < len(steps) else Spacer(1,1)
    step_rows.append([left, right])

steps_table = Table(step_rows, colWidths=[3.65*inch, 3.65*inch], hAlign="CENTER")
steps_table.setStyle(TableStyle([
    ("VALIGN",      (0,0),(-1,-1), "TOP"),
    ("LEFTPADDING", (0,0),(-1,-1), 0),
    ("RIGHTPADDING",(0,0),(-1,-1), 0),
    ("TOPPADDING",  (0,0),(-1,-1), 0),
    ("BOTTOMPADDING",(0,0),(-1,-1), 6),
    ("COLPADDING",  (0,0),(-1,-1), 6),
]))
story.append(steps_table)
story.append(Spacer(1, 10))

# ── KEY NUMBERS ───────────────────────────────────────────────────────────────
kn_header = Table(
    [[Paragraph("KEY NUMBERS TO REMEMBER", section_header)]],
    colWidths=[7.3*inch]
)
kn_header.setStyle(TableStyle([
    ("BACKGROUND",  (0,0),(-1,-1), TEAL),
    ("ROUNDEDCORNERS",[5]),
    ("TOPPADDING",  (0,0),(-1,-1), 5),
    ("BOTTOMPADDING",(0,0),(-1,-1), 5),
]))
story.append(kn_header)
story.append(Spacer(1, 6))

key_items = [
    ("100–120", "compressions\nper minute"),
    ("≥ 2\"",   "compression\ndepth"),
    ("30 : 2",  "compressions\nto breaths"),
    ("< 10 sec","max pause\nbetween compressions"),
    ("1 sec",   "per rescue\nbreath"),
]

kn_cells = []
for val, lbl in key_items:
    kn_cells.append(
        Table([
            [Paragraph(val, key_num_style)],
            [Paragraph(lbl.replace("\n","<br/>"), key_label_style)],
        ], colWidths=[1.36*inch])
    )

kn_table = Table([kn_cells], colWidths=[1.46*inch]*5)
kn_table.setStyle(TableStyle([
    ("BACKGROUND",  (0,0),(-1,-1), WHITE),
    ("BOX",         (0,0),(-1,-1), 0.5, colors.HexColor("#CCCCCC")),
    ("INNERGRID",   (0,0),(-1,-1), 0.5, colors.HexColor("#EEEEEE")),
    ("VALIGN",      (0,0),(-1,-1), "MIDDLE"),
    ("TOPPADDING",  (0,0),(-1,-1), 6),
    ("BOTTOMPADDING",(0,0),(-1,-1), 6),
]))
story.append(kn_table)
story.append(Spacer(1, 8))

# ── HANDS-ONLY NOTE ───────────────────────────────────────────────────────────
ho_data = [[
    Paragraph(
        "<b>HANDS-ONLY CPR:</b> If you are untrained or uncomfortable giving rescue breaths, "
        "continuous chest compressions alone (100–120/min) are still effective for adult bystander CPR. "
        "Any CPR is better than no CPR.",
        note_style
    )
]]
ho_table = Table(ho_data, colWidths=[7.3*inch])
ho_table.setStyle(TableStyle([
    ("BACKGROUND",  (0,0),(-1,-1), colors.HexColor("#EEF7F8")),
    ("BOX",         (0,0),(-1,-1), 1, TEAL),
    ("ROUNDEDCORNERS",[5]),
    ("TOPPADDING",  (0,0),(-1,-1), 7),
    ("BOTTOMPADDING",(0,0),(-1,-1), 7),
    ("LEFTPADDING", (0,0),(-1,-1), 10),
    ("RIGHTPADDING",(0,0),(-1,-1), 10),
]))
story.append(ho_table)
story.append(Spacer(1, 6))

# ── FOOTER ────────────────────────────────────────────────────────────────────
story.append(HRFlowable(width="100%", thickness=0.5, color=colors.HexColor("#CCCCCC")))
story.append(Spacer(1, 4))
story.append(Paragraph(
    "Based on 2025 AHA Guidelines for CPR & ECC and American Red Cross CPR Guidelines  |  "
    "This card is a quick reference only — formal CPR training is strongly recommended  |  "
    "Call 911 in all emergencies",
    footer_style
))

# ── BUILD ─────────────────────────────────────────────────────────────────────
doc.build(story)
print(f"PDF created: {OUTPUT}")

from reportlab.lib.pagesizes import letter
from reportlab.lib import colors
from reportlab.lib.units import inch
from reportlab.platypus import (
    SimpleDocTemplate, Paragraph, Spacer, Table, TableStyle,
    HRFlowable, KeepTogether, PageBreak
)
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.enums import TA_CENTER, TA_LEFT, TA_RIGHT

OUTPUT = "/home/daytona/workspace/cpr-guide/Shock_Notes_USMLE.pdf"

# ── Colour palette ────────────────────────────────────────────────────────────
NAVY      = colors.HexColor("#0D2137")
BLUE      = colors.HexColor("#1565C0")
LIGHT_BLUE= colors.HexColor("#E3F2FD")
MED_BLUE  = colors.HexColor("#BBDEFB")
TEAL      = colors.HexColor("#00695C")
LIGHT_TEAL= colors.HexColor("#E0F2F1")
RED       = colors.HexColor("#C62828")
LIGHT_RED = colors.HexColor("#FFEBEE")
ORANGE    = colors.HexColor("#E65100")
LIGHT_ORANGE = colors.HexColor("#FFF3E0")
PURPLE    = colors.HexColor("#6A1B9A")
LIGHT_PURPLE = colors.HexColor("#F3E5F5")
DARK_GRAY = colors.HexColor("#212121")
MID_GRAY  = colors.HexColor("#616161")
LIGHT_GRAY= colors.HexColor("#F5F5F5")
BORDER    = colors.HexColor("#CFD8DC")
WHITE     = colors.white
GOLD      = colors.HexColor("#F9A825")
LIGHT_GOLD= colors.HexColor("#FFFDE7")

# ── Doc setup ─────────────────────────────────────────────────────────────────
doc = SimpleDocTemplate(
    OUTPUT, pagesize=letter,
    leftMargin=0.55*inch, rightMargin=0.55*inch,
    topMargin=0.45*inch, bottomMargin=0.45*inch,
)

# ── Styles ────────────────────────────────────────────────────────────────────
def mks(name, **kw):
    base = dict(fontName="Helvetica", fontSize=9, textColor=DARK_GRAY, leading=13, spaceAfter=0, spaceBefore=0)
    base.update(kw)
    return ParagraphStyle(name, **base)

doc_title   = mks("DocTitle",   fontSize=22, fontName="Helvetica-Bold", textColor=WHITE, alignment=TA_CENTER, leading=26)
doc_sub     = mks("DocSub",     fontSize=10, fontName="Helvetica",       textColor=WHITE, alignment=TA_CENTER)
sec_hdr     = mks("SecHdr",     fontSize=11, fontName="Helvetica-Bold",  textColor=WHITE, alignment=TA_LEFT)
sub_hdr     = mks("SubHdr",     fontSize=10, fontName="Helvetica-Bold",  textColor=NAVY,  spaceAfter=2)
body        = mks("Body",       fontSize=8.5, leading=13)
body_bold   = mks("BodyBold",   fontSize=8.5, fontName="Helvetica-Bold", leading=13)
bullet_style= mks("Bullet",     fontSize=8.5, leading=13, leftIndent=10)
small       = mks("Small",      fontSize=7.5, textColor=MID_GRAY, leading=11)
tbl_hdr     = mks("TblHdr",     fontSize=8,   fontName="Helvetica-Bold", textColor=WHITE, alignment=TA_CENTER, leading=11)
tbl_cell    = mks("TblCell",    fontSize=8,   leading=11, alignment=TA_CENTER)
tbl_cell_l  = mks("TblCellL",   fontSize=8,   leading=11, alignment=TA_LEFT)
tbl_label   = mks("TblLabel",   fontSize=8,   fontName="Helvetica-Bold", leading=11, alignment=TA_LEFT)
footer_s    = mks("Footer",     fontSize=7,   textColor=MID_GRAY, alignment=TA_CENTER)
key_box     = mks("KeyBox",     fontSize=8.5, fontName="Helvetica-Bold", textColor=RED, alignment=TA_CENTER)
note_s      = mks("Note",       fontSize=8,   fontName="Helvetica-Oblique", textColor=MID_GRAY, leading=11)

story = []

# ══════════════════════════════════════════════════════════════════════════════
# PAGE HEADER
# ══════════════════════════════════════════════════════════════════════════════
hdr = Table([[
    Paragraph("SHOCK", doc_title),
    Paragraph("Medical Student / USMLE Notes  |  Pathophysiology · Classification · Hemodynamics · Management", doc_sub),
]], colWidths=[doc.width])
hdr.setStyle(TableStyle([
    ("BACKGROUND",   (0,0),(-1,-1), NAVY),
    ("TOPPADDING",   (0,0),(-1,-1), 10),
    ("BOTTOMPADDING",(0,0),(-1,-1), 10),
    ("LEFTPADDING",  (0,0),(-1,-1), 14),
]))
story.append(hdr)
story.append(Spacer(1,8))

# helper: coloured section bar
def sec_bar(text, colour=BLUE):
    t = Table([[Paragraph(text, sec_hdr)]], colWidths=[doc.width])
    t.setStyle(TableStyle([
        ("BACKGROUND",   (0,0),(-1,-1), colour),
        ("TOPPADDING",   (0,0),(-1,-1), 4),
        ("BOTTOMPADDING",(0,0),(-1,-1), 4),
        ("LEFTPADDING",  (0,0),(-1,-1), 8),
    ]))
    return t

def colored_box(content_rows, bg=LIGHT_BLUE, border=BLUE):
    t = Table(content_rows, colWidths=[doc.width])
    t.setStyle(TableStyle([
        ("BACKGROUND",   (0,0),(-1,-1), bg),
        ("BOX",          (0,0),(-1,-1), 0.8, border),
        ("TOPPADDING",   (0,0),(-1,-1), 5),
        ("BOTTOMPADDING",(0,0),(-1,-1), 5),
        ("LEFTPADDING",  (0,0),(-1,-1), 8),
        ("RIGHTPADDING", (0,0),(-1,-1), 8),
    ]))
    return t

# ══════════════════════════════════════════════════════════════════════════════
# 1. DEFINITION
# ══════════════════════════════════════════════════════════════════════════════
story.append(sec_bar("1.  DEFINITION"))
story.append(Spacer(1,5))
def_box = colored_box([[
    Paragraph(
        "<b>Shock</b> = a state of <b>acute circulatory failure</b> causing <b>tissue hypoperfusion</b> "
        "and cellular hypoxia. Oxygen delivery to tissues is insufficient to meet metabolic demands, "
        "resulting in anaerobic metabolism, lactic acidosis, and — if uncorrected — irreversible organ failure and death.",
        body)
]], LIGHT_BLUE, BLUE)
story.append(def_box)
story.append(Spacer(1,4))

# Key formula
formula_data = [
    [Paragraph("Oxygen Delivery (DO<sub rise='2'>2</sub>)", tbl_hdr),
     Paragraph("= Cardiac Output (CO) × Arterial O<sub rise='2'>2</sub> Content (CaO<sub rise='2'>2</sub>)", tbl_cell)],
    [Paragraph("CO = HR × Stroke Volume", tbl_hdr),
     Paragraph("CaO<sub rise='2'>2</sub> = (Hb × 1.34 × SaO<sub rise='2'>2</sub>) + (0.003 × PaO<sub rise='2'>2</sub>)", tbl_cell)],
]
formula_t = Table(formula_data, colWidths=[2.5*inch, 5.0*inch])
formula_t.setStyle(TableStyle([
    ("BACKGROUND",   (0,0),(0,-1), NAVY),
    ("BACKGROUND",   (1,0),(1,-1), LIGHT_BLUE),
    ("TEXTCOLOR",    (0,0),(0,-1), WHITE),
    ("GRID",         (0,0),(-1,-1), 0.5, BORDER),
    ("TOPPADDING",   (0,0),(-1,-1), 4),
    ("BOTTOMPADDING",(0,0),(-1,-1), 4),
    ("LEFTPADDING",  (0,0),(-1,-1), 6),
]))
story.append(formula_t)
story.append(Spacer(1,8))

# ══════════════════════════════════════════════════════════════════════════════
# 2. CLASSIFICATION
# ══════════════════════════════════════════════════════════════════════════════
story.append(sec_bar("2.  CLASSIFICATION OF SHOCK"))
story.append(Spacer(1,5))

class_colours = [BLUE, RED, TEAL, PURPLE]
class_data_raw = [
    ("HYPOVOLEMIC", BLUE, LIGHT_BLUE,
     "Low intravascular volume → ↓ preload → ↓ CO",
     "Hemorrhage, severe burns, vomiting/diarrhea, third-spacing, dehydration",
     "Tachycardia, ↓BP, cool/clammy skin, flat neck veins, oliguria",
     "IV fluids; blood products (pRBC:FFP:plt 1:1:1) for hemorrhage; control bleeding"),
    ("CARDIOGENIC", RED, LIGHT_RED,
     "Pump failure → ↓ CO despite normal/high volume",
     "MI (>40% LV loss), arrhythmia, myocarditis, valvular failure, cardiac tamponade",
     "Tachycardia, ↓BP, pulmonary edema (crackles), JVD, cool/clammy skin, S3",
     "Inotropes (dobutamine), vasopressors (NE); PCI for STEMI; IABP/MCS if refractory"),
    ("DISTRIBUTIVE", TEAL, LIGHT_TEAL,
     "Pathological vasodilation → ↓ SVR → relative hypovolemia; includes septic, anaphylactic, neurogenic",
     "Sepsis/bacteremia, anaphylaxis (IgE), spinal cord injury, adrenal crisis",
     "Septic: fever, warm/flushed skin early; Anaphylactic: urticaria, bronchospasm; Neurogenic: bradycardia + hypotension",
     "Septic: NE + broad antibiotics + fluids; Anaphylactic: IM epinephrine (FIRST LINE); Neurogenic: NE/phenylephrine"),
    ("OBSTRUCTIVE", PURPLE, LIGHT_PURPLE,
     "Mechanical block of cardiac output",
     "Massive PE, tension pneumothorax, cardiac tamponade, aortic dissection",
     "Tension PTX: absent breath sounds, tracheal deviation, JVD; Tamponade: Beck's triad; PE: pleuritic chest pain, hypoxia",
     "Tension PTX: needle decompression → chest tube; Tamponade: pericardiocentesis; Massive PE: anticoag ± thrombolytics"),
]

for name, col, light, mech, causes, sx, tx in class_data_raw:
    row1 = Table([[Paragraph(name, mks("TN", fontSize=10, fontName="Helvetica-Bold", textColor=WHITE, alignment=TA_LEFT))]], colWidths=[doc.width])
    row1.setStyle(TableStyle([("BACKGROUND",(0,0),(-1,-1),col),("TOPPADDING",(0,0),(-1,-1),3),("BOTTOMPADDING",(0,0),(-1,-1),3),("LEFTPADDING",(0,0),(-1,-1),8)]))
    inner = [
        [Paragraph("<b>Mechanism:</b>", body_bold), Paragraph(mech, body)],
        [Paragraph("<b>Causes:</b>", body_bold),    Paragraph(causes, body)],
        [Paragraph("<b>Signs/Sx:</b>", body_bold),  Paragraph(sx, body)],
        [Paragraph("<b>Treatment:</b>", body_bold), Paragraph(tx, body)],
    ]
    inner_t = Table(inner, colWidths=[1.1*inch, doc.width-1.1*inch])
    inner_t.setStyle(TableStyle([
        ("BACKGROUND",   (0,0),(-1,-1), light),
        ("TOPPADDING",   (0,0),(-1,-1), 3),
        ("BOTTOMPADDING",(0,0),(-1,-1), 3),
        ("LEFTPADDING",  (0,0),(-0,-1), 8),
        ("LEFTPADDING",  (1,0),(1,-1), 4),
        ("VALIGN",       (0,0),(-1,-1), "TOP"),
    ]))
    story.append(KeepTogether([row1, inner_t]))
    story.append(Spacer(1, 5))

story.append(Spacer(1,4))

# ══════════════════════════════════════════════════════════════════════════════
# 3. HEMODYNAMIC COMPARISON CHART
# ══════════════════════════════════════════════════════════════════════════════
story.append(sec_bar("3.  HEMODYNAMIC COMPARISON CHART  ★ HIGH-YIELD", ORANGE))
story.append(Spacer(1,5))

hdrs = ["Parameter", "Hypovolemic", "Cardiogenic", "Distributive\n(Septic)", "Obstructive\n(Tamponade/PE)"]
hdr_cols = [NAVY, BLUE, RED, TEAL, PURPLE]

rows = [
    ["CO / CI",       "↓↓",      "↓↓↓",    "↑↑ (early)\n↓ (late)", "↓↓"],
    ["SVR",           "↑↑",      "↑↑",     "↓↓",           "↑↑"],
    ["CVP / PCWP",    "↓↓",      "↑↑",     "↓ or normal",  "↑ (PCWP)\n↑ (CVP)"],
    ["HR",            "↑",       "↑",      "↑↑",           "↑"],
    ["BP (Systolic)", "↓",       "↓",      "↓",            "↓"],
    ["Pulse pressure","Narrow",  "Narrow", "Wide (early)",  "Narrow (pulsus paradoxus)"],
    ["SvO₂",         "↓",       "↓",      "↑ (early)\n↓ (late)", "↓"],
    ["Skin",         "Cool/pale","Cool/clammy","Warm/flushed\n(early)", "Cool/pale"],
    ["JVD",          "Absent",   "Present","Absent",        "Present"],
    ["Lung sounds",  "Clear",    "Crackles","Clear",         "Clear (tamponade)\nAbsent (PTX)"],
    ["Urine output", "↓",       "↓",      "↓",             "↓"],
    ["Lactate",      "↑",       "↑",      "↑",             "↑"],
    ["1st-line Rx",  "IV fluids\n+ blood products","Dobutamine\n+ NE + PCI","NE + antibiotics\n+ fluids","Decompress /\npericardiocentesis"],
]

col_w = [1.55*inch, 1.4*inch, 1.4*inch, 1.4*inch, 1.65*inch]

# Header row
hdr_row = [Paragraph(h.replace("\n","<br/>"), tbl_hdr) for h in hdrs]
all_rows = [hdr_row]

# Alternating shading
alt = [colors.HexColor("#EEF2FF"), WHITE]
for i, r in enumerate(rows):
    bg = alt[i % 2]
    all_rows.append([
        Paragraph("<b>" + r[0] + "</b>", tbl_label),
        *[Paragraph(c.replace("\n","<br/>"), tbl_cell) for c in r[1:]]
    ])

hd_table = Table(all_rows, colWidths=col_w)

ts = TableStyle([
    ("GRID",          (0,0),(-1,-1), 0.4, BORDER),
    ("TOPPADDING",    (0,0),(-1,-1), 4),
    ("BOTTOMPADDING", (0,0),(-1,-1), 4),
    ("LEFTPADDING",   (0,0),(-1,-1), 4),
    ("RIGHTPADDING",  (0,0),(-1,-1), 4),
    ("VALIGN",        (0,0),(-1,-1), "MIDDLE"),
    # header row backgrounds by type
    ("BACKGROUND", (0,0),(0,0), NAVY),
    ("BACKGROUND", (1,0),(1,0), BLUE),
    ("BACKGROUND", (2,0),(2,0), RED),
    ("BACKGROUND", (3,0),(3,0), TEAL),
    ("BACKGROUND", (4,0),(4,0), PURPLE),
    # param col
    ("BACKGROUND", (0,1),(0,-1), colors.HexColor("#ECEFF1")),
])
# alternating row fill
for i in range(len(rows)):
    bg = colors.HexColor("#EEF2FF") if i % 2 == 0 else WHITE
    ts.add("BACKGROUND", (1, i+1), (-1, i+1), bg)

hd_table.setStyle(ts)
story.append(hd_table)
story.append(Spacer(1, 6))

# ══════════════════════════════════════════════════════════════════════════════
# 4. THREE STAGES OF SHOCK
# ══════════════════════════════════════════════════════════════════════════════
story.append(sec_bar("4.  THREE STAGES OF SHOCK", colors.HexColor("#37474F")))
story.append(Spacer(1, 5))

stage_data = [
    ["Stage 1\nCOMPENSATED\n(Nonprogressive)", colors.HexColor("#1565C0"), LIGHT_BLUE,
     "Baroreceptors activate → catecholamines, ADH, RAAS\n"
     "• Tachycardia, ↑ SVR, renal fluid conservation\n"
     "• Blood shunted from skin/gut → heart and brain\n"
     "• No overt organ dysfunction; lactate mildly ↑\n"
     "• Skin: cool and pale (warm/flushed in early sepsis)"],
    ["Stage 2\nDECOMPENSATED\n(Progressive)", colors.HexColor("#BF360C"), LIGHT_RED,
     "Compensatory mechanisms overwhelmed\n"
     "• Anaerobic glycolysis → lactic acidosis → pH ↓\n"
     "• Arterioles dilate → blood pools in microcirculation\n"
     "• DIC may develop from endothelial injury\n"
     "• Vital organs (kidney, heart, bowel) begin to fail"],
    ["Stage 3\nIRREVERSIBLE", colors.HexColor("#4A148C"), LIGHT_PURPLE,
     "Lysosomal enzyme leakage amplifies cell destruction\n"
     "• ↑ Nitric oxide → worsening myocardial contractility\n"
     "• Ischemic gut → bacterial translocation → bacteremia\n"
     "• Multisystem organ failure (MSOF)\n"
     "• Death even if hemodynamics are corrected"],
]

stage_cells = []
for label, col, light, details in stage_data:
    label_t = Table([[Paragraph(label.replace("\n","<br/>"), mks("SL", fontSize=8.5, fontName="Helvetica-Bold", textColor=WHITE, alignment=TA_CENTER))]],
                    colWidths=[1.4*inch])
    label_t.setStyle(TableStyle([("BACKGROUND",(0,0),(-1,-1),col),("TOPPADDING",(0,0),(-1,-1),6),("BOTTOMPADDING",(0,0),(-1,-1),6)]))
    detail_t = Table([[Paragraph(details.replace("\n","<br/>"), mks("SD", fontSize=8, leading=12))]],
                     colWidths=[doc.width/3 - 1.5*inch])
    detail_t.setStyle(TableStyle([("BACKGROUND",(0,0),(-1,-1),light),("TOPPADDING",(0,0),(-1,-1),5),("BOTTOMPADDING",(0,0),(-1,-1),5),("LEFTPADDING",(0,0),(-1,-1),6)]))
    cell = Table([[label_t],[detail_t]], colWidths=[doc.width/3])
    cell.setStyle(TableStyle([("TOPPADDING",(0,0),(-1,-1),0),("BOTTOMPADDING",(0,0),(-1,-1),0),("LEFTPADDING",(0,0),(-1,-1),0),("RIGHTPADDING",(0,0),(-1,-1),0)]))
    stage_cells.append(cell)

stage_row = Table([stage_cells], colWidths=[doc.width/3]*3)
stage_row.setStyle(TableStyle([("TOPPADDING",(0,0),(-1,-1),0),("BOTTOMPADDING",(0,0),(-1,-1),0),("LEFTPADDING",(0,0),(-1,-1),2),("RIGHTPADDING",(0,0),(-1,-1),2)]))
story.append(stage_row)
story.append(Spacer(1,8))

# ══════════════════════════════════════════════════════════════════════════════
# 5. DIAGNOSIS & LAB MARKERS
# ══════════════════════════════════════════════════════════════════════════════
story.append(sec_bar("5.  DIAGNOSIS  —  CLINICAL CRITERIA & LAB MARKERS", colors.HexColor("#37474F")))
story.append(Spacer(1,5))

diag_left = [
    [Paragraph("<b>Empirical Criteria for Shock (any majority):</b>", body_bold)],
    [Paragraph("• Ill appearance / altered mental status", bullet_style)],
    [Paragraph("• HR > 100 bpm", bullet_style)],
    [Paragraph("• RR > 20 /min  or  PaCO₂ < 32 mmHg", bullet_style)],
    [Paragraph("• Base deficit < −4 mEq/L  or  Lactate > 4 mmol/L", bullet_style)],
    [Paragraph("• Urine output < 0.5 mL/kg/h", bullet_style)],
    [Paragraph("• SBP < 90 mmHg or MAP < 65 mmHg sustained > 30 min", bullet_style)],
    [Paragraph("<i>Note: Shock can occur with NORMAL BP (especially early / distributive)</i>", note_s)],
]
diag_right = [
    [Paragraph("<b>Key Lab Markers:</b>", body_bold)],
    [Paragraph("• <b>Lactate > 4 mmol/L</b>  →  tissue hypoperfusion; predicts organ failure", bullet_style)],
    [Paragraph("• <b>Base deficit < −4 mEq/L</b>  →  equivalent to lactate elevation", bullet_style)],
    [Paragraph("• <b>Rising lactate + worsening base deficit</b>  →  refractory shock", bullet_style)],
    [Paragraph("• <b>Creatinine / BUN ↑</b>  →  acute kidney injury", bullet_style)],
    [Paragraph("• <b>Troponin ↑</b>  →  myocardial injury (cardiogenic or demand ischemia)", bullet_style)],
    [Paragraph("• <b>Procalcitonin, CRP ↑</b>  →  sepsis markers", bullet_style)],
    [Paragraph("• <b>Coags (PT/INR/fibrinogen/D-dimer)</b>  →  DIC screen", bullet_style)],
]

left_t = Table(diag_left, colWidths=[(doc.width/2)-4])
left_t.setStyle(TableStyle([("BACKGROUND",(0,0),(-1,-1),LIGHT_BLUE),("BOX",(0,0),(-1,-1),0.5,BLUE),("TOPPADDING",(0,0),(-1,-1),3),("BOTTOMPADDING",(0,0),(-1,-1),3),("LEFTPADDING",(0,0),(-1,-1),6)]))
right_t = Table(diag_right, colWidths=[(doc.width/2)-4])
right_t.setStyle(TableStyle([("BACKGROUND",(0,0),(-1,-1),LIGHT_TEAL),("BOX",(0,0),(-1,-1),0.5,TEAL),("TOPPADDING",(0,0),(-1,-1),3),("BOTTOMPADDING",(0,0),(-1,-1),3),("LEFTPADDING",(0,0),(-1,-1),6)]))

diag_row = Table([[left_t, right_t]], colWidths=[doc.width/2, doc.width/2])
diag_row.setStyle(TableStyle([("LEFTPADDING",(0,0),(-1,-1),0),("RIGHTPADDING",(0,0),(-1,-1),0),("TOPPADDING",(0,0),(-1,-1),0),("BOTTOMPADDING",(0,0),(-1,-1),0),("COLPADDING",(0,0),(-1,-1),4)]))
story.append(diag_row)
story.append(Spacer(1,8))

# ══════════════════════════════════════════════════════════════════════════════
# 6. SEPTIC SHOCK — PATHOGENESIS
# ══════════════════════════════════════════════════════════════════════════════
story.append(sec_bar("6.  SEPTIC SHOCK — PATHOGENESIS (HIGH DETAIL)", RED))
story.append(Spacer(1,5))

sepsis_steps = [
    ("Microbial Trigger", "Endotoxin (LPS), exotoxins, fungal antigens activate TLRs on macrophages/dendritic cells via PAMPs & DAMPs"),
    ("NF-κB Activation", "TLR signaling → NF-κB nuclear translocation → transcription of TNF, IL-1, IL-6, IL-12, IL-18, IFN-γ, HMGB1"),
    ("Complement Activation", "Microbial components directly activate complement → C3a/C5a (anaphylatoxins) → further inflammation, vasodilation"),
    ("Endothelial Injury", "Cytokines ↑ adhesion molecules; coagulation activated via factor XII → widespread microvascular thrombosis, DIC"),
    ("Vasodilation / ↓ SVR", "NO (nitric oxide) massively ↑ → profound vasodilation → distributive shock; relative hypovolemia"),
    ("Counter-regulation", "Counter-regulatory immunosuppression: lymphocyte apoptosis, Th1→Th2 shift, IL-10 ↑ → oscillation between hyperinflammation and immunosuppression"),
    ("Organ Failure", "ARDS (lung), AKI, hepatic dysfunction, DIC, encephalopathy — SOFA score used to quantify organ failure"),
]

sep_rows = [[Paragraph(f"<b>{a}</b>", mks("SA", fontSize=8, fontName="Helvetica-Bold", textColor=DARK_GRAY)),
             Paragraph(b, mks("SB", fontSize=8, leading=12))] for a, b in sepsis_steps]
sep_t = Table(sep_rows, colWidths=[1.6*inch, doc.width-1.6*inch])
sep_t.setStyle(TableStyle([
    ("GRID",          (0,0),(-1,-1), 0.4, BORDER),
    ("BACKGROUND",    (0,0),(0,-1), colors.HexColor("#FFCDD2")),
    ("BACKGROUND",    (1,0),(1,-1), LIGHT_RED),
    ("TOPPADDING",    (0,0),(-1,-1), 4),
    ("BOTTOMPADDING", (0,0),(-1,-1), 4),
    ("LEFTPADDING",   (0,0),(-1,-1), 6),
    ("VALIGN",        (0,0),(-1,-1), "TOP"),
]))
story.append(sep_t)
story.append(Spacer(1, 4))

# Sepsis definitions box
sep_def = Table([[Paragraph(
    "<b>Definitions (Sepsis-3):</b>  "
    "<b>Sepsis</b> = life-threatening organ dysfunction (SOFA score ↑≥2) from dysregulated host response to infection.  "
    "<b>Septic Shock</b> = Sepsis + vasopressor requirement to maintain MAP ≥65 + lactate >2 mmol/L despite adequate fluids.  "
    "Mortality ~40%.",
    mks("SepDef", fontSize=8.5, leading=12))
]], colWidths=[doc.width])
sep_def.setStyle(TableStyle([("BACKGROUND",(0,0),(-1,-1),colors.HexColor("#FFEBEE")),("BOX",(0,0),(-1,-1),1,RED),("TOPPADDING",(0,0),(-1,-1),5),("BOTTOMPADDING",(0,0),(-1,-1),5),("LEFTPADDING",(0,0),(-1,-1),8)]))
story.append(sep_def)
story.append(Spacer(1,8))

# ══════════════════════════════════════════════════════════════════════════════
# 7. VASOPRESSOR / VASOACTIVE DRUG TABLE
# ══════════════════════════════════════════════════════════════════════════════
story.append(sec_bar("7.  VASOACTIVE DRUGS IN SHOCK", ORANGE))
story.append(Spacer(1,5))

vaso_hdrs = ["Drug", "Dose", "Receptors", "Main Effect", "Use in Shock"]
vaso_rows = [
    ["Norepinephrine\n(1st line — septic)", "3–30 µg/min", "α1 > β1", "↑SVR + modest ↑CO", "Septic, distributive;\npreferred over dopamine"],
    ["Epinephrine", "5–20 µg/min", "α + β1 + β2", "↑CO + ↑SVR\n(also bronchodilation)", "Anaphylaxis (IM first!\nthen IV infusion); refractory septic"],
    ["Vasopressin", "0.01–0.04 U/min", "V1 receptors", "↑SVR; no ↑HR;\nno ↑pulm. vasc. resistance", "Adjunct to NE in septic;\nuseful with pulm. HTN or RV failure"],
    ["Dobutamine", "2–15 µg/kg/min", "β1 > β2", "↑CO (inotrope);\n↓SVR slightly", "Cardiogenic shock;\nlow CO states"],
    ["Dopamine\n(not preferred)", "varies", "DA > β > α\n(dose-dependent)", "Low: renal vasodilation\nHigh: ↑SVR", "No longer recommended;\n↑arrhythmias vs NE"],
    ["Phenylephrine", "2–300 µg/min", "Pure α1", "↑SVR; reflex ↓HR", "Neurogenic shock;\ncontraindicated if low CO"],
]

vaso_cols = [1.5*inch, 1.05*inch, 1.1*inch, 1.6*inch, 2.15*inch]
v_hdr_row = [Paragraph(h, tbl_hdr) for h in vaso_hdrs]
v_all = [v_hdr_row]
for i, r in enumerate(vaso_rows):
    bg = colors.HexColor("#FFF8E1") if i % 2 == 0 else WHITE
    v_all.append([Paragraph(c.replace("\n","<br/>"), tbl_cell_l if j==0 else tbl_cell) for j,c in enumerate(r)])

v_table = Table(v_all, colWidths=vaso_cols)
v_ts = TableStyle([
    ("GRID",          (0,0),(-1,-1), 0.4, BORDER),
    ("BACKGROUND",    (0,0),(-1,0), ORANGE),
    ("TOPPADDING",    (0,0),(-1,-1), 4),
    ("BOTTOMPADDING", (0,0),(-1,-1), 4),
    ("LEFTPADDING",   (0,0),(-1,-1), 4),
    ("RIGHTPADDING",  (0,0),(-1,-1), 4),
    ("VALIGN",        (0,0),(-1,-1), "TOP"),
])
for i in range(len(vaso_rows)):
    bg = colors.HexColor("#FFF8E1") if i % 2 == 0 else WHITE
    v_ts.add("BACKGROUND", (0,i+1),(-1,i+1), bg)
v_table.setStyle(v_ts)
story.append(v_table)
story.append(Spacer(1,8))

# ══════════════════════════════════════════════════════════════════════════════
# 8. ORGAN PATHOLOGY IN SHOCK
# ══════════════════════════════════════════════════════════════════════════════
story.append(sec_bar("8.  ORGAN PATHOLOGY IN SHOCK", colors.HexColor("#37474F")))
story.append(Spacer(1,5))

organs = [
    ("Kidney",    "Acute Tubular Necrosis (ATN)",         "Most common cause of AKI; ischemic injury to proximal tubule and loop of Henle; granular 'muddy brown' casts on UA"),
    ("Lung",      "ARDS / 'Shock Lung'",                  "Diffuse alveolar damage; especially in septic and traumatic shock; protein-rich edema, hyaline membranes"),
    ("Heart",     "Subendocardial infarction",             "Ischemia of inner 1/3 of myocardium; diffuse non-territorial; ST depression on ECG; supply-demand mismatch"),
    ("Brain",     "Ischemic encephalopathy",               "Watershed zone infarcts; altered mental status; neurons and cardiomyocytes cannot regenerate"),
    ("GI Tract",  "Hemorrhagic enteropathy / Ischemic bowel", "Mucosal ulceration; bacterial translocation into bloodstream → superimposed bacteremia"),
    ("Adrenals",  "Cortical lipid depletion",              "Reflects maximal steroid synthesis; in overwhelming sepsis → Waterhouse-Friderichsen syndrome (adrenal hemorrhage)"),
    ("Liver",     "Centrilobular necrosis / 'Shock liver'","Zone 3 (centrilobular) most susceptible; ↑ transaminases; may resolve with resuscitation"),
]

org_hdr = [Paragraph(h, tbl_hdr) for h in ["Organ", "Lesion", "Notes"]]
org_rows = [org_hdr]
for i, (org, les, notes) in enumerate(organs):
    bg = colors.HexColor("#ECEFF1") if i % 2 == 0 else WHITE
    org_rows.append([
        Paragraph(f"<b>{org}</b>", tbl_label),
        Paragraph(les, tbl_cell_l),
        Paragraph(notes, mks("ON", fontSize=7.8, leading=11)),
    ])
org_t = Table(org_rows, colWidths=[1.0*inch, 1.8*inch, 4.6*inch])
org_ts = TableStyle([
    ("GRID",          (0,0),(-1,-1), 0.4, BORDER),
    ("BACKGROUND",    (0,0),(-1,0), colors.HexColor("#37474F")),
    ("TOPPADDING",    (0,0),(-1,-1), 4),
    ("BOTTOMPADDING", (0,0),(-1,-1), 4),
    ("LEFTPADDING",   (0,0),(-1,-1), 4),
    ("VALIGN",        (0,0),(-1,-1), "TOP"),
])
for i in range(len(organs)):
    bg = colors.HexColor("#ECEFF1") if i % 2 == 0 else WHITE
    org_ts.add("BACKGROUND", (0,i+1),(-1,i+1), bg)
org_t.setStyle(org_ts)
story.append(org_t)
story.append(Spacer(1,8))

# ══════════════════════════════════════════════════════════════════════════════
# 9. USMLE HIGH-YIELD PEARLS
# ══════════════════════════════════════════════════════════════════════════════
story.append(sec_bar("9.  USMLE HIGH-YIELD PEARLS  ⭐", GOLD))
story.append(Spacer(1,5))

pearls = [
    "Only type of shock with HIGH PCWP + LOW CO + HIGH SVR = CARDIOGENIC",
    "Only type of shock with LOW SVR + HIGH CO (early) = DISTRIBUTIVE (septic)",
    "Hypovolemic + Cardiogenic both show: ↓CO, ↑SVR, ↓CVP/PCWP (except cardiogenic has ↑PCWP)",
    "Beck's Triad (tamponade) = Hypotension + JVD + Muffled heart sounds → pericardiocentesis",
    "Tension PTX = Absent breath sounds + tracheal deviation away + JVD → NEEDLE decompression 2nd ICS MCL",
    "1st-line vasopressor for septic shock = NOREPINEPHRINE (not dopamine — ↑ arrhythmias with dopamine)",
    "1st-line treatment for anaphylactic shock = IM EPINEPHRINE (thigh) — do NOT give antihistamines first",
    "Lactate > 4 mmol/L OR base deficit < -4 mEq/L = presumptive shock regardless of BP",
    "Neurogenic shock = hypotension + BRADYCARDIA (not tachycardia) — from loss of sympathetic tone",
    "Cardiogenic shock post-MI defined as: SBP <90 + CI <2.2 L/min/m² + PCWP >18 mmHg",
    "Urine output < 0.5 mL/kg/h = severe renal hypoperfusion marker in shock",
    "SOFA score used to define/track organ dysfunction in sepsis; ↑≥2 from baseline = sepsis",
]

pearl_rows = []
for i, p in enumerate(pearls):
    bg = LIGHT_GOLD if i % 2 == 0 else WHITE
    pearl_rows.append([
        Paragraph(f"★", mks("Star", fontSize=9, fontName="Helvetica-Bold", textColor=GOLD, alignment=TA_CENTER)),
        Paragraph(p, mks("Pearl", fontSize=8.5, leading=12))
    ])

pearl_t = Table(pearl_rows, colWidths=[0.25*inch, doc.width-0.25*inch])
p_ts = TableStyle([
    ("GRID",          (0,0),(-1,-1), 0.3, BORDER),
    ("TOPPADDING",    (0,0),(-1,-1), 4),
    ("BOTTOMPADDING", (0,0),(-1,-1), 4),
    ("LEFTPADDING",   (0,0),(-1,-1), 5),
    ("VALIGN",        (0,0),(-1,-1), "MIDDLE"),
])
for i in range(len(pearls)):
    bg = LIGHT_GOLD if i % 2 == 0 else WHITE
    p_ts.add("BACKGROUND", (0,i),(-1,i), bg)
pearl_t.setStyle(p_ts)
story.append(pearl_t)
story.append(Spacer(1,8))

# ══════════════════════════════════════════════════════════════════════════════
# FOOTER
# ══════════════════════════════════════════════════════════════════════════════
story.append(HRFlowable(width="100%", thickness=0.5, color=BORDER))
story.append(Spacer(1,3))
story.append(Paragraph(
    "Sources: Robbins, Cotran & Kumar — Pathologic Basis of Disease (10e) | Harrison's Principles of Internal Medicine (22e) | "
    "Rosen's Emergency Medicine | Goldman-Cecil Medicine | Sabiston Textbook of Surgery | Schwartz's Principles of Surgery  "
    "| For educational use only — verify with current clinical guidelines",
    footer_s
))

doc.build(story)
print(f"PDF created: {OUTPUT}")

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Shock Notes — USMLE / Medical Student</title>
<style>
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  *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
  body {
    font-family: 'Segoe UI', Arial, sans-serif;
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  /* ── Print styles ── */
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    body { background: white; padding: 0; font-size: 11px; }
    .page { box-shadow: none; margin: 0; padding: 12mm; max-width: 100%; }
    .no-print { display: none; }
    section { page-break-inside: avoid; }
    h2.sec-bar { page-break-after: avoid; }
    @page { margin: 10mm; size: A4; }
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  /* ── Page wrapper ── */
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    max-width: 1000px;
    margin: 0 auto 30px;
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    border-radius: 6px;
    overflow: hidden;
    padding-bottom: 16px;
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  /* ── Print button ── */
  .print-btn {
    display: block;
    width: 200px;
    margin: 0 auto 18px;
    padding: 12px 0;
    background: #1565C0;
    color: white;
    border: none;
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    font-size: 15px;
    font-weight: bold;
    cursor: pointer;
    text-align: center;
    letter-spacing: 0.5px;
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  .print-btn:hover { background: #0D47A1; }

  /* ── Header banner ── */
  .header {
    background: linear-gradient(135deg, #0D2137 0%, #1565C0 100%);
    color: white;
    padding: 18px 24px 14px;
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  .header h1 { font-size: 28px; letter-spacing: 2px; margin-bottom: 4px; }
  .header p  { font-size: 11px; opacity: 0.85; letter-spacing: 0.5px; }

  /* ── Section bars ── */
  h2.sec-bar {
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    text-transform: uppercase;
    margin: 14px 12px 8px;
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  /* ── Content padding ── */
  .inner { padding: 0 12px; }

  /* ── Definition box ── */
  .def-box {
    background: #E3F2FD;
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    font-weight: bold;
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    background: #BBDEFB;
    border-radius: 4px;
    padding: 6px 12px;
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  /* ── Classification cards ── */
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    display: grid;
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    padding: 5px 10px;
    letter-spacing: 1px;
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  .card-body { padding: 8px 10px; font-size: 12px; line-height: 1.6; }
  .card-body b { color: #333; }
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<body>

<button class="print-btn no-print" onclick="window.print()">🖨 Print / Save as PDF</button>

<div class="page">

  <!-- HEADER -->
  <div class="header">
    <h1>SHOCK</h1>
    <p>Medical Student / USMLE Notes &nbsp;|&nbsp; Pathophysiology · Classification · Hemodynamics · Management</p>
  </div>

  <!-- ══ 1. DEFINITION ══ -->
  <h2 class="sec-bar bar-blue">1. Definition</h2>
  <div class="inner">
    <div class="def-box">
      <b>Shock</b> = a state of <b>acute circulatory failure</b> causing <b>tissue hypoperfusion</b> and cellular hypoxia.
      Oxygen delivery to tissues is insufficient to meet metabolic demands, resulting in anaerobic metabolism,
      lactic acidosis, and — if uncorrected — irreversible multi-organ failure and death.
      At the subcellular level, <b>mitochondria</b> are the first organelles affected (consume &gt;95% of O₂).
    </div>
    <div class="formula-row">
      <span class="formula-pill">O₂ Delivery (DO₂) = CO × CaO₂</span>
      <span class="formula-val">CO = HR × Stroke Volume</span>
      <span class="formula-val">CaO₂ = (Hb × 1.34 × SaO₂) + (0.003 × PaO₂)</span>
    </div>
  </div>

  <!-- ══ 2. CLASSIFICATION ══ -->
  <h2 class="sec-bar bar-blue">2. Classification of Shock</h2>
  <div class="inner">
    <div class="cards-grid">

      <div class="card hypo">
        <div class="card-header">HYPOVOLEMIC</div>
        <div class="card-body">
          <div class="card-row"><span class="label">Mechanism:</span> Low intravascular volume → ↓ preload → ↓ CO</div>
          <div class="card-row"><span class="label">Causes:</span> Hemorrhage, severe burns, vomiting/diarrhea, third-spacing, dehydration</div>
          <div class="card-row"><span class="label">Signs:</span> Tachycardia, ↓BP, cool/clammy skin, flat neck veins, oliguria</div>
          <div class="card-row"><span class="label">Treatment:</span> IV fluids; blood products (pRBC:FFP:plt 1:1:1) for hemorrhage; control bleeding</div>
        </div>
      </div>

      <div class="card cardio">
        <div class="card-header">CARDIOGENIC</div>
        <div class="card-body">
          <div class="card-row"><span class="label">Mechanism:</span> Pump failure → ↓ CO despite normal/high filling volume</div>
          <div class="card-row"><span class="label">Causes:</span> MI (&gt;40% LV loss), arrhythmia, myocarditis, valvular failure, cardiac tamponade</div>
          <div class="card-row"><span class="label">Signs:</span> Tachycardia, ↓BP, pulmonary edema (crackles), JVD, cool/clammy skin, S3 gallop</div>
          <div class="card-row"><span class="label">Treatment:</span> Dobutamine (inotrope) + norepinephrine; PCI for STEMI; IABP/MCS if refractory</div>
        </div>
      </div>

      <div class="card distrib">
        <div class="card-header">DISTRIBUTIVE (Septic / Anaphylactic / Neurogenic)</div>
        <div class="card-body">
          <div class="card-row"><span class="label">Mechanism:</span> Pathological vasodilation → ↓ SVR → relative hypovolemia</div>
          <div class="card-row"><span class="label">Causes:</span> Sepsis/bacteremia, anaphylaxis (IgE-mediated), spinal cord injury, adrenal crisis</div>
          <div class="card-row"><span class="label">Signs:</span> Septic: fever, warm/flushed early; Anaphylactic: urticaria, bronchospasm; Neurogenic: hypotension + bradycardia</div>
          <div class="card-row"><span class="label">Treatment:</span> Septic: NE + antibiotics + fluids; Anaphylactic: <b>IM epinephrine FIRST</b>; Neurogenic: NE or phenylephrine</div>
        </div>
      </div>

      <div class="card obstruct">
        <div class="card-header">OBSTRUCTIVE</div>
        <div class="card-body">
          <div class="card-row"><span class="label">Mechanism:</span> Mechanical block of cardiac output</div>
          <div class="card-row"><span class="label">Causes:</span> Massive PE, tension pneumothorax, cardiac tamponade, aortic dissection</div>
          <div class="card-row"><span class="label">Signs:</span> Tension PTX: absent breath sounds, tracheal deviation, JVD; Tamponade: Beck's triad; PE: pleuritic chest pain, hypoxia</div>
          <div class="card-row"><span class="label">Treatment:</span> Tension PTX: needle decompression → chest tube; Tamponade: pericardiocentesis; Massive PE: anticoag ± thrombolytics</div>
        </div>
      </div>

    </div>
  </div>

  <!-- ══ 3. HEMODYNAMIC COMPARISON CHART ══ -->
  <h2 class="sec-bar bar-orange">3. Hemodynamic Comparison Chart ★ HIGH-YIELD</h2>
  <div class="inner">
    <table class="hd-table">
      <thead>
        <tr>
          <th>Parameter</th>
          <th>Hypovolemic</th>
          <th>Cardiogenic</th>
          <th>Distributive (Septic)</th>
          <th>Obstructive (Tamponade/PE)</th>
        </tr>
      </thead>
      <tbody>
        <tr><td>CO / CI</td><td class="down">↓↓</td><td class="down">↓↓↓</td><td><span class="up">↑↑ early</span> / <span class="down">↓ late</span></td><td class="down">↓↓</td></tr>
        <tr><td>SVR</td><td class="up">↑↑</td><td class="up">↑↑</td><td class="down">↓↓</td><td class="up">↑↑</td></tr>
        <tr><td>CVP / PCWP</td><td class="down">↓↓</td><td class="up">↑↑</td><td class="down">↓ or normal</td><td><span class="up">↑ CVP</span> / <span class="up">↑ PCWP</span></td></tr>
        <tr><td>Heart Rate</td><td class="up">↑</td><td class="up">↑</td><td class="up">↑↑</td><td class="up">↑</td></tr>
        <tr><td>Blood Pressure</td><td class="down">↓</td><td class="down">↓</td><td class="down">↓</td><td class="down">↓</td></tr>
        <tr><td>Pulse Pressure</td><td>Narrow</td><td>Narrow</td><td>Wide (early)</td><td>Narrow / pulsus paradoxus</td></tr>
        <tr><td>SvO₂</td><td class="down">↓</td><td class="down">↓</td><td><span class="up">↑ early</span> / <span class="down">↓ late</span></td><td class="down">↓</td></tr>
        <tr><td>Skin</td><td>Cool / pale</td><td>Cool / clammy</td><td>Warm / flushed (early)</td><td>Cool / pale</td></tr>
        <tr><td>JVD</td><td>Absent</td><td>Present</td><td>Absent</td><td>Present</td></tr>
        <tr><td>Lung Sounds</td><td>Clear</td><td>Crackles (pulm. edema)</td><td>Clear</td><td>Clear (tamponade); Absent (PTX)</td></tr>
        <tr><td>Urine Output</td><td class="down">↓</td><td class="down">↓</td><td class="down">↓</td><td class="down">↓</td></tr>
        <tr><td>Lactate</td><td class="up">↑</td><td class="up">↑</td><td class="up">↑</td><td class="up">↑</td></tr>
        <tr>
          <td><b>1st-line Rx</b></td>
          <td>IV fluids + blood products (1:1:1)</td>
          <td>Dobutamine + NE; PCI for STEMI</td>
          <td>Norepinephrine + antibiotics + fluids</td>
          <td>Decompress / pericardiocentesis / anticoag</td>
        </tr>
      </tbody>
    </table>
    <p style="font-size:11px; color:#616161; margin-bottom:10px;">
      <b>Cardiogenic shock definition:</b> SBP &lt;90 mmHg + CI &lt;2.2 L/min/m² + PCWP &gt;18 mmHg
    </p>
  </div>

  <!-- ══ 4. THREE STAGES ══ -->
  <h2 class="sec-bar bar-gray">4. Three Stages of Shock</h2>
  <div class="inner">
    <div class="stages-grid">
      <div class="stage s1">
        <div class="stage-header">STAGE 1<br>COMPENSATED (Nonprogressive)</div>
        <div class="stage-body">
          <ul>
            <li>Baroreceptors activate → catecholamines, ADH, RAAS</li>
            <li>Tachycardia, ↑ SVR, renal fluid conservation</li>
            <li>Blood shunted: skin/gut → heart and brain</li>
            <li>No overt organ dysfunction yet</li>
            <li>Lactate mildly ↑; creatinine may rise</li>
            <li>Skin: cool/pale (warm/flushed in early sepsis)</li>
          </ul>
        </div>
      </div>
      <div class="stage s2">
        <div class="stage-header">STAGE 2<br>DECOMPENSATED (Progressive)</div>
        <div class="stage-body">
          <ul>
            <li>Compensatory mechanisms overwhelmed</li>
            <li>Anaerobic glycolysis → lactic acidosis</li>
            <li>↓ pH blunts vasomotor response → arterioles dilate</li>
            <li>Blood pools in microcirculation → worsens CO</li>
            <li>DIC develops from endothelial injury</li>
            <li>Vital organs (kidney, heart, bowel) begin to fail</li>
          </ul>
        </div>
      </div>
      <div class="stage s3">
        <div class="stage-header">STAGE 3<br>IRREVERSIBLE</div>
        <div class="stage-body">
          <ul>
            <li>Lysosomal enzyme leakage amplifies destruction</li>
            <li>↑ NO → myocardial contractility worsens further</li>
            <li>Ischemic gut → bacterial translocation → bacteremia</li>
            <li>Multisystem organ failure (MSOF)</li>
            <li>Death even if hemodynamics corrected</li>
          </ul>
        </div>
      </div>
    </div>
  </div>

  <!-- ══ 5. DIAGNOSIS ══ -->
  <h2 class="sec-bar bar-gray">5. Diagnosis — Clinical Criteria &amp; Lab Markers</h2>
  <div class="inner">
    <div class="diag-grid">
      <div class="diag-box blue">
        <b>Empirical Criteria for Shock (majority should be met):</b>
        <ul>
          <li>Ill appearance / altered mental status</li>
          <li>HR &gt; 100 bpm</li>
          <li>RR &gt; 20/min  or  PaCO₂ &lt; 32 mmHg</li>
          <li>Base deficit &lt; −4 mEq/L  or  Lactate &gt; 4 mmol/L</li>
          <li>Urine output &lt; 0.5 mL/kg/h</li>
          <li>SBP &lt; 90 mmHg or MAP &lt; 65 mmHg &gt; 30 min</li>
        </ul>
        <p class="note">⚠ Shock can occur with NORMAL BP — especially early or in distributive states</p>
      </div>
      <div class="diag-box teal">
        <b>Key Lab Markers:</b>
        <ul>
          <li><b>Lactate &gt; 4 mmol/L</b> → tissue hypoperfusion; predicts organ failure</li>
          <li><b>Base deficit &lt; −4 mEq/L</b> → equivalent to lactate elevation</li>
          <li><b>Rising lactate + worsening BD</b> → refractory shock</li>
          <li><b>Creatinine / BUN ↑</b> → acute kidney injury</li>
          <li><b>Troponin ↑</b> → myocardial injury (demand ischemia)</li>
          <li><b>Procalcitonin, CRP ↑</b> → sepsis markers</li>
          <li><b>PT/INR/fibrinogen/D-dimer</b> → DIC screen</li>
        </ul>
      </div>
    </div>
  </div>

  <!-- ══ 6. SEPTIC SHOCK PATHOGENESIS ══ -->
  <h2 class="sec-bar bar-red">6. Septic Shock — Pathogenesis (High Detail)</h2>
  <div class="inner">
    <table class="sep-table">
      <tbody>
        <tr><td>Microbial Trigger</td><td>Endotoxin (LPS), exotoxins, fungal antigens activate TLRs on macrophages/dendritic cells via PAMPs &amp; DAMPs</td></tr>
        <tr><td>NF-κB Activation</td><td>TLR signaling → NF-κB nuclear translocation → transcription of TNF, IL-1, IL-6, IL-12, IL-18, IFN-γ, HMGB1</td></tr>
        <tr><td>Complement Activation</td><td>Microbial components activate complement → C3a/C5a (anaphylatoxins) → further inflammation and vasodilation</td></tr>
        <tr><td>Endothelial Injury</td><td>Cytokines ↑ adhesion molecules; coagulation activated via factor XII → widespread microvascular thrombosis, DIC</td></tr>
        <tr><td>Vasodilation / ↓SVR</td><td>Massive ↑ nitric oxide (NO) → profound vasodilation → distributive shock; relative hypovolemia</td></tr>
        <tr><td>Counter-regulation</td><td>Lymphocyte apoptosis, Th1→Th2 shift, ↑ IL-10 → immunosuppression; oscillation between hyperinflammation and immune suppression</td></tr>
        <tr><td>Organ Failure</td><td>ARDS, AKI, hepatic dysfunction, DIC, encephalopathy — SOFA score quantifies organ failure</td></tr>
      </tbody>
    </table>
    <div class="sep-def">
      <b>Sepsis-3 Definitions:</b>
      &nbsp;<b>Sepsis</b> = life-threatening organ dysfunction (SOFA ↑≥2 from baseline) caused by dysregulated host response to infection.
      &nbsp;<b>Septic Shock</b> = Sepsis + vasopressor requirement to maintain MAP ≥65 mmHg + lactate &gt;2 mmol/L despite adequate fluids.
      &nbsp;Mortality ≈ <b>40%</b>. Most common triggers: gram-positive bacteria &gt; gram-negative bacteria &gt; fungi.
    </div>
  </div>

  <!-- ══ 7. VASOACTIVE DRUGS ══ -->
  <h2 class="sec-bar bar-orange">7. Vasoactive Drugs in Shock</h2>
  <div class="inner">
    <table class="vaso-table">
      <thead>
        <tr>
          <th style="text-align:left">Drug</th>
          <th>Dose</th>
          <th>Receptors</th>
          <th>Main Effect</th>
          <th>Use in Shock</th>
        </tr>
      </thead>
      <tbody>
        <tr>
          <td><b>Norepinephrine</b><br><small>(1st line — septic)</small></td>
          <td>3–30 µg/min</td>
          <td>α1 &gt; β1</td>
          <td>↑ SVR + modest ↑ CO</td>
          <td class="left">Septic / distributive; preferred over dopamine</td>
        </tr>
        <tr>
          <td><b>Epinephrine</b></td>
          <td>5–20 µg/min (IV)<br>0.3–0.5 mg IM</td>
          <td>α + β1 + β2</td>
          <td>↑ CO + ↑ SVR; bronchodilation</td>
          <td class="left">Anaphylaxis: <b>IM FIRST</b>; refractory septic shock</td>
        </tr>
        <tr>
          <td><b>Vasopressin</b></td>
          <td>0.01–0.04 U/min</td>
          <td>V1 receptors</td>
          <td>↑ SVR; no ↑ HR; no ↑ pulm. resistance</td>
          <td class="left">Adjunct to NE in septic; useful with pulm. HTN or RV failure</td>
        </tr>
        <tr>
          <td><b>Dobutamine</b></td>
          <td>2–15 µg/kg/min</td>
          <td>β1 &gt; β2</td>
          <td>↑ CO (inotrope); ↓ SVR slightly</td>
          <td class="left">Cardiogenic shock; low CO states</td>
        </tr>
        <tr>
          <td><b>Dopamine</b><br><small>(not preferred)</small></td>
          <td>dose-dependent</td>
          <td>DA &gt; β &gt; α</td>
          <td>Variable by dose; ↑ arrhythmias</td>
          <td class="left">⚠ Not recommended — higher mortality vs NE in septic/cardiogenic</td>
        </tr>
        <tr>
          <td><b>Phenylephrine</b></td>
          <td>2–300 µg/min</td>
          <td>Pure α1</td>
          <td>↑ SVR; reflex ↓ HR</td>
          <td class="left">Neurogenic shock; avoid if low CO</td>
        </tr>
      </tbody>
    </table>
  </div>

  <!-- ══ 8. ORGAN PATHOLOGY ══ -->
  <h2 class="sec-bar bar-gray">8. Organ Pathology in Shock</h2>
  <div class="inner">
    <table class="organ-table">
      <thead>
        <tr>
          <th style="text-align:left">Organ</th>
          <th style="text-align:left">Lesion</th>
          <th style="text-align:left">Notes</th>
        </tr>
      </thead>
      <tbody>
        <tr>
          <td>Kidney</td>
          <td class="left">Acute Tubular Necrosis (ATN)</td>
          <td class="left">Most common cause of AKI; ischemic injury to proximal tubule; granular "muddy brown" casts on UA</td>
        </tr>
        <tr>
          <td>Lung</td>
          <td class="left">ARDS / "Shock Lung"</td>
          <td class="left">Diffuse alveolar damage; especially septic and traumatic shock; protein-rich edema, hyaline membranes</td>
        </tr>
        <tr>
          <td>Heart</td>
          <td class="left">Subendocardial infarction</td>
          <td class="left">Ischemia of inner 1/3 of myocardium; diffuse, non-territorial; ST depression; supply-demand mismatch</td>
        </tr>
        <tr>
          <td>Brain</td>
          <td class="left">Ischemic encephalopathy</td>
          <td class="left">Watershed zone infarcts; altered mental status; neurons and cardiomyocytes cannot regenerate</td>
        </tr>
        <tr>
          <td>GI Tract</td>
          <td class="left">Hemorrhagic enteropathy / Ischemic bowel</td>
          <td class="left">Mucosal ulceration; bacterial translocation into bloodstream → superimposed bacteremia worsens shock</td>
        </tr>
        <tr>
          <td>Adrenals</td>
          <td class="left">Cortical lipid depletion</td>
          <td class="left">Maximal steroid synthesis; overwhelming sepsis → Waterhouse-Friderichsen syndrome (adrenal hemorrhage)</td>
        </tr>
        <tr>
          <td>Liver</td>
          <td class="left">Centrilobular necrosis / "Shock liver"</td>
          <td class="left">Zone 3 (centrilobular) most susceptible; ↑ transaminases; may resolve if resuscitation succeeds</td>
        </tr>
      </tbody>
    </table>
  </div>

  <!-- ══ 9. USMLE PEARLS ══ -->
  <h2 class="sec-bar bar-gold">9. USMLE High-Yield Pearls ⭐</h2>
  <div class="inner">
    <ul class="pearl-list">
      <li>Only type with <b>HIGH PCWP + LOW CO + HIGH SVR</b> = <b>CARDIOGENIC</b></li>
      <li>Only type with <b>LOW SVR + HIGH CO (early)</b> = <b>DISTRIBUTIVE (septic)</b></li>
      <li>Hypovolemic vs Cardiogenic: both ↓CO, ↑SVR — difference is PCWP (↓ in hypovolemic, ↑↑ in cardiogenic)</li>
      <li><b>Beck's Triad</b> (tamponade) = Hypotension + JVD + Muffled heart sounds → <b>pericardiocentesis</b></li>
      <li><b>Tension PTX</b> = absent breath sounds + tracheal deviation away + JVD → <b>needle decompression 2nd ICS MCL</b></li>
      <li>1st-line vasopressor for septic shock = <b>NOREPINEPHRINE</b> (not dopamine — dopamine ↑ arrhythmias, ↑ mortality)</li>
      <li>1st-line for anaphylactic shock = <b>IM EPINEPHRINE (thigh)</b> — do NOT give antihistamines or steroids first</li>
      <li>Lactate &gt;4 mmol/L <b>OR</b> base deficit &lt; −4 mEq/L = presumptive shock regardless of BP</li>
      <li><b>Neurogenic shock</b> = hypotension + <b>BRADYCARDIA</b> (unlike all other shock types which cause tachycardia)</li>
      <li>Cardiogenic shock post-MI: SBP &lt;90 + CI &lt;2.2 L/min/m² + <b>PCWP &gt;18 mmHg</b></li>
      <li>Urine output &lt;0.5 mL/kg/h = severe renal hypoperfusion marker in any shock</li>
      <li><b>SOFA score ↑ ≥2</b> from baseline = sepsis; add vasopressor need + lactate &gt;2 = <b>septic shock</b></li>
    </ul>
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    Sources: Robbins, Cotran &amp; Kumar — Pathologic Basis of Disease (10e) | Harrison's Principles of Internal Medicine (22e) |
    Rosen's Emergency Medicine | Goldman-Cecil Medicine | Sabiston Textbook of Surgery | Schwartz's Principles of Surgery
    &nbsp;|&nbsp; For educational use only — verify with current clinical guidelines
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