Cookbook 327: Offline Clinical Emergency Medicine Shock Index, SIPA & Massive Transfusion Engine

"""
Cookbook 327: Offline Emergency Medicine Shock Index, SIPA & Massive Transfusion Engine
OpenPHR Clinical AI Working Group (https://openphr.org)
"""

import math
import numpy as np
import pandas as pd
from typing import Dict, List, Tuple, Optional
from dataclasses import dataclass

@dataclass
class TraumaPatientTelemetry:
    patient_id: str
    age_years: float = 34.0
    heart_rate_bpm: float = 128.0 # bpm
    systolic_bp_mmhg: float = 86.0 # mmHg
    glasgow_coma_scale: int = 13 # GCS 3-15
    # ABC Score Parameters
    is_penetrating_mechanism: bool = True # Gunshot, stab wound
    is_fast_ultrasound_positive: bool = True # Free fluid in abdomen/pelvis
    # Time Since Injury Telemetry
    hours_since_injury: float = 1.2 # hours (<= 3.0h = CRASH-2 TXA window)
    # Arterial Blood Gas & Electrolyte Telemetry
    blood_ph: float = 7.18 # Normal 7.35 - 7.45 (< 7.20 = Severe Acidosis)
    base_deficit_mmol_l: float = -8.5 # mmol/L (< -6 = Severe hypoperfusion)
    core_body_temperature_c: float = 34.4 # C (< 35.0 C = Hypothermia)
    ionized_calcium_mmol_l: float = 0.88 # mmol/L (< 1.0 = Severe Hypocalcemia)
    serum_lactate_mmol_l: float = 5.2 # mmol/L
    # Thromboelastography (TEG) Telemetry
    teg_r_time_minutes: float = 11.2 # Normal 5 - 10 min (> 10 = Factor deficiency -> FFP)
    teg_alpha_angle_degrees: float = 52.0 # Normal 60 - 75 deg (< 60 = Fibrinogen -> Cryo)
    teg_maximum_amplitude_mm: float = 46.0 # Normal 55 - 70 mm (< 55 = Platelets -> Plt)
    teg_ly30_percent: float = 6.4 # Normal 0 - 3% (> 3% = Hyperfibrinolysis -> TXA)

@dataclass
class TraumaResuscitationReport:
    patient_id: str
    shock_index_value: float
    shock_index_interpretation: str
    rsig_value: float
    rsig_interpretation: str
    abc_total_score: int # 0 - 4
    mtp_activation_status: str # "🚨 STAT MASSIVE TRANSFUSION PROTOCOL (MTP) ACTIVATED", "MTP Not Triggered"
    hemostatic_blood_product_orders: List[str]
    crash2_txa_protocol: List[str]
    teg_guided_component_therapy: List[str]
    lethal_triad_safety_sentinels: List[str]
    clinical_acscot_atls_directive: str

class TraumaResuscitationDecisionEngine:
    """
    Offline clinical engine for Shock Index / SIPA / rSIG evaluation, ABC score calculation,
    1:1:1 Massive Transfusion Protocol activation, and TEG-directed hemostatic resuscitation.
    """

    def calculate_shock_indices(self, d: TraumaPatientTelemetry) -> Tuple[float, str, float, str]:
        # Adult Shock Index: HR / SBP
        si = round(d.heart_rate_bpm / max(d.systolic_bp_mmhg, 30.0), 2)

        # Pediatric Age-Adjusted Shock Index (SIPA) if < 17 years old
        if d.age_years < 17.0:
            if d.age_years <= 6.0:
                sipa_cutoff = 1.22
            elif d.age_years <= 12.0:
                sipa_cutoff = 1.00
            else:
                sipa_cutoff = 0.90

            if si > sipa_cutoff:
                si_interp = f"ELEVATED SIPA ({si:.2f} > {sipa_cutoff:.2f} age-specific cutoff for {d.age_years:.0f}yo) -> High risk of uncompensated pediatric shock."
            else:
                si_interp = f"Normal SIPA ({si:.2f} <= {sipa_cutoff:.2f} cutoff)."
        else:
            if si >= 1.3:
                si_interp = f"CRITICAL SHOCK INDEX ({si:.2f} >= 1.3) -> Impending cardiovascular collapse; severe hemorrhage (>40% blood loss)."
            elif si >= 0.9:
                si_interp = f"HIGH SHOCK INDEX ({si:.2f} >= 0.9) -> Uncompensated hemorrhagic shock; high likelihood of transfusion & ICU admission."
            elif si >= 0.7:
                si_interp = f"MILD / OCCULT SHOCK ({si:.2f} between 0.7-0.9) -> Compensated shock."
            else:
                si_interp = f"Normal Shock Index ({si:.2f} between 0.5-0.7)."

        # Reverse Shock Index x GCS (rSIG) = (SBP / HR) * GCS
        rsig = round((d.systolic_bp_mmhg / max(d.heart_rate_bpm, 30.0)) * d.glasgow_coma_scale, 2)
        if rsig < 7.8:
            rsig_interp = f"CRITICAL rSIG ({rsig:.2f} < 7.8 cutoff) -> High mortality risk; powerful predictor of massive transfusion and emergent surgical/angio intervention."
        else:
            rsig_interp = f"Non-Critical rSIG ({rsig:.2f} >= 7.8)."

        return si, si_interp, rsig, rsig_interp

    def calculate_abc_score(self, d: TraumaPatientTelemetry) -> Tuple[int, str]:
        score = 0
        if d.is_penetrating_mechanism: score += 1
        if d.systolic_bp_mmhg <= 90.0: score += 1
        if d.heart_rate_bpm >= 120.0: score += 1
        if d.is_fast_ultrasound_positive: score += 1

        status = "🚨 STAT MASSIVE TRANSFUSION PROTOCOL (MTP) ACTIVATED (ABC Score >= 2)" if score >= 2 else f"MTP Not Immediately Triggered (ABC Score {score}/4 < 2)"
        return score, status

    def generate_resuscitation_protocols(self, is_mtp: bool, d: TraumaPatientTelemetry) -> Tuple[List[str], List[str], List[str], List[str]]:
        blood_orders = []
        txa_plan = []
        teg_plan = []
        sentinels = []

        # 1. Balanced 1:1:1 Blood Product Protocol
        if is_mtp:
            blood_orders.append("1. STAT MTP COOLER PACK 1 (1:1:1 Ratio):")
            blood_orders.append("   • 6 Units Packed Red Blood Cells (pRBC) (O-negative for women of childbearing age; O-positive for males/older females).")
            blood_orders.append("   • 6 Units Fresh Frozen Plasma (FFP) (or Thawed Plasma).")
            blood_orders.append("   • 1 Apheresis Unit Single-Donor Platelets (or 6-pack pooled).")
            blood_orders.append("2. RESTRICT CRYSTALLOIDS: Limit crystalloid boluses (< 1.0 L total) to prevent dilutional coagulopathy, hypothermia, and worsening acidosis.")
        else:
            blood_orders.append("1. Type & Crossmatch 2-4 units pRBC; maintain hemostatic readiness.")

        # 2. CRASH-2 Tranexamic Acid (TXA) Protocol
        if d.hours_since_injury <= 3.0:
            txa_plan.append(f"1. STAT TXA LOADING DOSE (Golden Window {d.hours_since_injury:.1f}h <= 3.0h): Administer Tranexamic Acid 1.0 g IV in 100 mL NS over 10 minutes.")
            txa_plan.append("2. TXA MAINTENANCE INFUSION: Follow immediately with Tranexamic Acid 1.0 g IV continuous infusion in 250-500 mL NS over 8 hours.")
        else:
            txa_plan.append(f"⛔ TXA CONTRAINDICATED (> 3.0h from injury: {d.hours_since_injury:.1f}h). CRASH-2 trial demonstrates increased thrombotic mortality if given after 3 hours.")

        # 3. Viscoelastic TEG-Guided Component Resuscitation
        if d.teg_r_time_minutes > 10.0:
            teg_plan.append(f"• Prolonged R-Time ({d.teg_r_time_minutes:.1f} min > 10 min) -> Clotting factor deficiency: Transfuse 2-4 Units FFP or 4-Factor PCC.")
        if d.teg_alpha_angle_degrees < 60.0:
            teg_plan.append(f"• Decreased Alpha Angle ({d.teg_alpha_angle_degrees:.1f} deg < 60 deg) -> Impaired fibrin kinetics: Transfuse 10-20 Units Cryoprecipitate (Target Fibrinogen >= 150-200 mg/dL).")
        if d.teg_maximum_amplitude_mm < 55.0:
            teg_plan.append(f"• Decreased Maximum Amplitude ({d.teg_maximum_amplitude_mm:.1f} mm < 55 mm) -> Platelet deficiency/dysfunction: Transfuse 1 Apheresis Unit Platelets.")
        if d.teg_ly30_percent > 3.0:
            teg_plan.append(f"• Elevated LY30 ({d.teg_ly30_percent:.1f}% > 3.0%) -> Severe hyperfibrinolysis: Ensure full TXA dosing and repeat TEG in 30 min.")

        # 4. Lethal Triad Sentinels
        if d.core_body_temperature_c < 35.0:
            sentinels.append(f"HYPOTHERMIA SENTINEL (Temp {d.core_body_temperature_c:.1f} C < 35.0 C): Causes severe enzymatic clotting dysfunction. Initiate active forced-air rewarming and rapid fluid warming (Belmont/Level 1 at 42 C).")

        if d.blood_ph < 7.20 or d.base_deficit_mmol_l < -6.0:
            sentinels.append(f"SEVERE ACIDOSIS SENTINEL (pH {d.blood_ph:.2f}, Base Deficit {d.base_deficit_mmol_l:.1f} mmol/L): Profound tissue hypoperfusion. Prioritize surgical damage-control hemostasis and volume restoration over sodium bicarbonate.")

        if d.ionized_calcium_mmol_l < 1.0:
            sentinels.append(f"HYPOCALCEMIA CITRATE SENTINEL (iCa {d.ionized_calcium_mmol_l:.2f} mmol/L < 1.0 mmol/L): Banked blood citrate causes severe hypocalcemia leading to myocardial depression and coagulopathy. STAT administer 1.0 - 2.0 g Calcium Chloride IV per 4 units pRBC transfused.")

        return blood_orders, txa_plan, teg_plan, sentinels

    def evaluate_case(self, data: TraumaPatientTelemetry) -> TraumaResuscitationReport:
        si_val, si_desc, rsig_val, rsig_desc = self.calculate_shock_indices(data)
        abc_score, mtp_status = self.calculate_abc_score(data)
        is_mtp = "ACTIVATED" in mtp_status
        blood_plan, txa_plan, teg_plan, sentinels = self.generate_resuscitation_protocols(is_mtp, data)

        directives = []
        directives.append(f"SHOCK INDEX: {si_val} ({si_desc}).")
        directives.append(f"rSIG: {rsig_val} ({rsig_desc}).")
        directives.append(f"ABC SCORE: {abc_score}/4 -> {mtp_status}.")

        return TraumaResuscitationReport(
            patient_id=data.patient_id,
            shock_index_value=si_val,
            shock_index_interpretation=si_desc,
            rsig_value=rsig_val,
            rsig_interpretation=rsig_desc,
            abc_total_score=abc_score,
            mtp_activation_status=mtp_status,
            hemostatic_blood_product_orders=blood_plan,
            crash2_txa_protocol=txa_plan,
            teg_guided_component_therapy=teg_plan,
            lethal_triad_safety_sentinels=sentinels,
            clinical_acscot_atls_directive=" ".join(directives)
        )

# Example Execution & Verification
if __name__ == "__main__":
    engine = TraumaResuscitationDecisionEngine()

    print("=" * 80)
    print("OpenPHR Clinical Emergency Medicine Shock Index & Massive Transfusion Engine")
    print("=" * 80)

    # Test Case 1: 34-year-old male with penetrating gunshot wound to abdomen.
    # HR: 128 bpm, SBP: 86 mmHg, GCS: 13, Positive FAST. Time from injury: 1.2h.
    # SI: 1.49 (Critical Shock), rSIG: 8.73, ABC Score: 4/4 -> STAT MTP 1:1:1 Activation!
    # TEG: R-time 11.2 min (FFP), alpha 52 deg (Cryo), MA 46 mm (Plt), LY30 6.4% (TXA).
    # Lethal Triad: Temp 34.4 C, pH 7.18, iCa 0.88 mmol/L -> Active warming & CaCl2 sentinels!
    trauma1 = TraumaPatientTelemetry(
        patient_id="TRAUMA-EM-8801",
        age_years=34.0,
        heart_rate_bpm=128.0,
        systolic_bp_mmhg=86.0,
        glasgow_coma_scale=13,
        is_penetrating_mechanism=True,
        is_fast_ultrasound_positive=True,
        hours_since_injury=1.2,
        blood_ph=7.18,
        base_deficit_mmol_l=-8.5,
        core_body_temperature_c=34.4,
        ionized_calcium_mmol_l=0.88,
        serum_lactate_mmol_l=5.2,
        teg_r_time_minutes=11.2,
        teg_alpha_angle_degrees=52.0,
        teg_maximum_amplitude_mm=46.0,
        teg_ly30_percent=6.4
    )

    rep1 = engine.evaluate_case(trauma1)

    print(f"\n[Patient {rep1.patient_id} - Trauma Bay Resuscitation Assessment]")
    print(f"Shock Index: {rep1.shock_index_value:.2f} — {rep1.shock_index_interpretation}")
    print(f"rSIG Index: {rep1.rsig_value:.2f} — {rep1.rsig_interpretation}")
    print(f"ABC Score: {rep1.abc_total_score}/4 — {rep1.mtp_activation_status}")
    print("\nHemostatic Blood Product Orders (1:1:1 MTP):")
    for b in rep1.hemostatic_blood_product_orders:
        print(f"  {b}")
    print("\nCRASH-2 Tranexamic Acid (TXA) Orders:")
    for txa in rep1.crash2_txa_protocol:
        print(f"  {txa}")
    print("\nTEG-Guided Targeted Component Resuscitation:")
    for teg in rep1.teg_guided_component_therapy:
        print(f"  {teg}")
    if rep1.lethal_triad_safety_sentinels:
        print("\nTrauma Lethal Triad Safety Sentinels:")
        for s in rep1.lethal_triad_safety_sentinels:
            print(f"  🚨 {s}")
    print(f"\nACS-COT / ATLS Directive:\n{rep1.clinical_acscot_atls_directive}")