pediatric-ai-scribe-v3/public/js/bedside/toxicology.js

// ============================================================
// bedside/toxicology.js
// TOXICOLOGY.
// ============================================================

import { S } from './shared.js';

function lookupTox() {
  var wt = parseFloat(document.getElementById('tox-weight').value);
  var topic = document.getElementById('tox-topic').value;
  var el = document.getElementById('tox-result');
  var html = '';

  if (topic === 'approach') {
    html += S.stepBox('#3b82f6', '1. Stabilize (ABCDE)', 'Airway, breathing, circulation, disability (glucose, pupils, GCS), exposure. Naloxone if depressed LOC + resp depression. Dextrose if hypoglycemic. Thiamine in select cases.');
    html += S.stepBox('#8b5cf6', '2. Identify toxidrome', '<strong>Sympathomimetic:</strong> HTN, tachy, mydriasis, diaphoresis (cocaine, meth). <strong>Anticholinergic:</strong> hot/dry, mydriasis, tachy, delirium (antihistamines, TCAs). <strong>Cholinergic:</strong> SLUDGE-M, miosis (organophosphates). <strong>Opioid:</strong> miosis, resp depression, ↓LOC. <strong>Sedative-hypnotic:</strong> ↓LOC, normal/low vitals.');
    html += S.stepBox('#f59e0b', '3. Decontamination', '<strong>Activated charcoal</strong> 1 g/kg PO (max 50 g): within 1h of ingestion, intact airway, ingestion adsorbed (not Li, metals, alcohols). Avoid caustics/hydrocarbons. <strong>Whole bowel irrigation:</strong> PEG for metals/iron/lithium/sustained release. <strong>Gastric lavage:</strong> rarely indicated. <strong>Ipecac:</strong> no longer recommended.');
    html += S.stepBox('#10b981', '4. Enhance elimination', '<strong>Urinary alkalinization</strong> (salicylates, phenobarbital). <strong>Hemodialysis</strong> (see ISTUMBLE). <strong>Lipid emulsion</strong> for lipid-soluble drug toxicity (LA, CCB, TCA).');
    html += S.stepBox('#ef4444', '5. Antidotes', 'See topic list. <strong>Contact Poison Center</strong> (US: 1-800-222-1222) early for any significant exposure.');
  } else if (topic === 'acetaminophen') {
    html += '<div style="padding:10px 14px;border-radius:8px;background:var(--blue-light);border:1.5px solid var(--blue);margin-bottom:10px;"><strong>Acetaminophen overdose</strong></div>';
    html += '<p style="font-size:13px;">Acute toxic dose: &gt;150 mg/kg (or 7.5 g total) single ingestion. Hepatotoxic after 24h; AST/ALT peak day 3-4.</p>';
    html += '<p style="font-size:13px;"><strong>Diagnosis:</strong> Draw level at 4h post-ingestion (or on arrival if &gt;4h). Plot on <strong>Rumack-Matthew nomogram</strong> (treatment line at 150 mcg/mL at 4h).</p>';
    html += S.drugTable(
      S.drugRow('N-acetylcysteine (NAC) — IV', '150 mg/kg over 1h → 50 mg/kg over 4h → 100 mg/kg over 16h (21h total)', 'IV', 'Total 300 mg/kg. Most effective if started &lt;8h post-ingestion.') +
      S.drugRow('N-acetylcysteine — PO', '140 mg/kg load, then 70 mg/kg q4h × 17 doses', 'PO', 'Alternative to IV. Unpleasant taste — often with juice.') +
      S.drugRow('Activated charcoal', '1 g/kg (max 50 g)', 'PO', 'If within 1-2h of ingestion and airway protected.')
    );
    if (wt) html += '<div style="padding:10px;background:var(--g50);border-radius:6px;font-size:12px;"><strong>For ' + wt + ' kg:</strong> IV loading = ' + S.d(wt, 150) + ' mg over 1h <span style="color:var(--g500);font-size:11px;">(150 mg/kg)</span>; 2nd bag = ' + S.d(wt, 50) + ' mg over 4h <span style="color:var(--g500);font-size:11px;">(50 mg/kg)</span>; 3rd bag = ' + S.d(wt, 100) + ' mg over 16h <span style="color:var(--g500);font-size:11px;">(100 mg/kg)</span>. <em>Total 300 mg/kg.</em></div>';
  } else if (topic === 'opioids') {
    html += '<div style="padding:10px 14px;border-radius:8px;background:var(--blue-light);border:1.5px solid var(--blue);margin-bottom:10px;"><strong>Opioid overdose</strong></div>';
    html += '<p style="font-size:13px;">Triad: <strong>miosis + respiratory depression + ↓ LOC</strong>. Fentanyl / synthetics may require repeated/higher doses.</p>';
    html += S.drugTable(
      S.drugRow('Naloxone (initial)', '0.01-0.1 mg/kg' + (wt ? ' = ' + S.d(wt, 0.01) + '-' + S.d(wt, 0.1) + ' mg' : ''), 'IV / IM / IN / IO', 'Start low if chronic opioid use (avoid withdrawal). Titrate to respiratory effort, not consciousness.') +
      S.drugRow('Naloxone (full reversal)', '2 mg IV/IM/IN', 'IV / IM / IN', 'If no chronic use and severe resp depression. Repeat q2-3 min.') +
      S.drugRow('Naloxone infusion', '2/3 of effective bolus per hour', 'IV', 'For long-acting opioids (methadone, fentanyl patch, sustained release)')
    );
    html += '<div style="padding:10px;background:#fef3c7;border-radius:6px;font-size:12px;color:#92400e;margin-top:10px;">Observe ≥4h after last dose; longer for long-acting agents. Duration of naloxone (30-90 min) is shorter than most opioids — <strong>re-sedation is common</strong>.</div>';
  } else if (topic === 'iron') {
    html += '<div style="padding:10px 14px;border-radius:8px;background:var(--blue-light);border:1.5px solid var(--blue);margin-bottom:10px;"><strong>Iron overdose</strong></div>';
    html += '<p style="font-size:13px;">Toxic dose: elemental Fe ≥20 mg/kg. Severe ≥60 mg/kg. <strong>Charcoal does NOT bind iron.</strong></p>';
    html += '<p style="font-size:13px;"><strong>Stages:</strong> 1) GI (0-6h: vomiting, bloody diarrhea); 2) Latent (6-24h: deceptive improvement); 3) Shock/metabolic acidosis (12-24h); 4) Hepatotoxicity (2-5d); 5) Gastric scarring (2-8 wk).</p>';
    html += S.drugTable(
      S.drugRow('Whole bowel irrigation', 'PEG-ES 25-40 mL/kg/hr', 'NG', 'For radiopaque pills on KUB or ingested sustained-release iron.') +
      S.drugRow('Deferoxamine', '15 mg/kg/hr IV infusion', 'IV', 'Max 6-8 g/day. Indications: shock, metabolic acidosis, Fe level &gt;500 mcg/dL, or severe symptoms. Urine turns "vin rosé" color.')
    );
    html += '<div style="padding:10px;background:#fef3c7;border-radius:6px;font-size:12px;color:#92400e;margin-top:10px;">Iron level at 4-6h. &lt;350 usually asymptomatic; 350-500 mild; &gt;500 severe. Consider KUB for radiopaque pills.</div>';
  } else if (topic === 'tca') {
    html += '<div style="padding:10px 14px;border-radius:8px;background:var(--blue-light);border:1.5px solid var(--blue);margin-bottom:10px;"><strong>TCA overdose</strong></div>';
    html += '<p style="font-size:13px;">Anticholinergic + Na-channel blockade. <strong>Risks:</strong> seizure, VT/VF, hypotension, coma. ECG: QRS &gt;100 ms or R in aVR &gt;3 mm predicts toxicity.</p>';
    html += S.drugTable(
      S.drugRow('Sodium bicarbonate 8.4%', '1-2 mEq/kg IV bolus → infusion', 'IV', 'Goal pH 7.45-7.55 and narrowing QRS. Repeat bolus for QRS widening, hypotension, or arrhythmia.') +
      S.drugRow('Mg sulfate', S.dStr(wt || 30, 50, 2000, ' mg'), 'IV over 10 min', 'For torsades.') +
      S.drugRow('IV lipid emulsion 20%', '1.5 mL/kg bolus → 0.25 mL/kg/min × 30-60 min', 'IV', 'If refractory shock/arrest. Consult toxicology.')
    );
    html += '<div style="padding:10px;background:#fef3c7;border-radius:6px;font-size:12px;color:#92400e;margin-top:10px;"><strong>Avoid</strong> Class IA/IC antiarrhythmics, beta-blockers, physostigmine (risk of asystole with TCAs).</div>';
  } else if (topic === 'bbccb') {
    html += '<div style="padding:10px 14px;border-radius:8px;background:var(--blue-light);border:1.5px solid var(--blue);margin-bottom:10px;"><strong>β-blocker / Calcium-channel blocker overdose</strong></div>';
    html += '<p style="font-size:13px;">Bradycardia + hypotension. CCBs (esp. verapamil, diltiazem, amlodipine) can be lethal in small pediatric doses.</p>';
    html += S.drugTable(
      S.drugRow('IV fluids', '20 mL/kg NS bolus', 'IV', 'Cautious — avoid volume overload') +
      S.drugRow('Calcium chloride 10% or gluconate', 'CaCl 20 mg/kg / Ca-glu 60 mg/kg', 'IV', 'First-line for CCB. Repeat q15-20 min.') +
      S.drugRow('Glucagon', '50 mcg/kg IV bolus → 50-150 mcg/kg/hr', 'IV', 'β-blocker antidote. GI side effects common.') +
      S.drugRow('High-dose insulin (HIE)', 'Regular insulin 1 U/kg bolus → 0.5-2 U/kg/hr + D25% infusion', 'IV', 'Hyperinsulinemic euglycemia therapy. Monitor K+ and glucose closely.') +
      S.drugRow('Vasopressors', 'Epi / norepi infusion', 'IV', 'Titrate to MAP.') +
      S.drugRow('Lipid emulsion 20%', '1.5 mL/kg → 0.25 mL/kg/min', 'IV', 'For lipid-soluble CCBs (verapamil) if refractory.') +
      S.drugRow('Methylene blue / ECMO', '—', '—', 'Rescue therapy — toxicology/ICU consult.')
    );
  } else if (topic === 'benzo') {
    html += '<div style="padding:10px 14px;border-radius:8px;background:var(--blue-light);border:1.5px solid var(--blue);margin-bottom:10px;"><strong>Benzodiazepine overdose</strong></div>';
    html += '<p style="font-size:13px;">Sedation + resp depression. Usually supportive — intubation rarely needed alone. <strong>Flumazenil caution.</strong></p>';
    html += S.drugTable(
      S.drugRow('Flumazenil', '0.01 mg/kg (max 0.2 mg) IV, may repeat q1 min to max 1 mg', 'IV', 'Only for iatrogenic reversal in a benzo-naive patient with no TCAs, seizure disorder, or chronic benzo use. <strong>Can precipitate seizures.</strong>')
    );
    html += '<div style="padding:10px;background:#fef3c7;border-radius:6px;font-size:12px;color:#92400e;margin-top:10px;">In real-world ingestion, <strong>supportive care (airway, monitoring)</strong> is usually safer than flumazenil.</div>';
  } else if (topic === 'organo') {
    html += '<div style="padding:10px 14px;border-radius:8px;background:var(--blue-light);border:1.5px solid var(--blue);margin-bottom:10px;"><strong>Organophosphate / carbamate poisoning</strong></div>';
    html += '<p style="font-size:13px;">Cholinergic toxidrome: <strong>SLUDGE-M</strong> (salivation, lacrimation, urination, defecation, GI distress, emesis, miosis) + muscle fasciculation, bradycardia, bronchorrhea. Decontamination critical (PPE for providers).</p>';
    html += S.drugTable(
      S.drugRow('Atropine', '0.05 mg/kg IV, double q3-5 min until bronchial secretions dry', 'IV', 'Endpoint = dry lungs, not dry mouth or heart rate. Can require huge doses.') +
      S.drugRow('Pralidoxime (2-PAM)', '25-50 mg/kg IV over 30 min (max 2 g) → 10-20 mg/kg/hr', 'IV', 'Only for organophosphates (not carbamates). Regenerates acetylcholinesterase.') +
      S.drugRow('Diazepam / midazolam', 'Standard seizure doses', 'IV', 'For seizures or severe fasciculations.')
    );
  } else if (topic === 'salicylate') {
    html += '<div style="padding:10px 14px;border-radius:8px;background:var(--blue-light);border:1.5px solid var(--blue);margin-bottom:10px;"><strong>Salicylate overdose</strong></div>';
    html += '<p style="font-size:13px;">Mixed respiratory alkalosis + anion gap metabolic acidosis. Tinnitus, tachypnea, diaphoresis, hyperthermia. Severe: CNS depression, seizures, pulmonary edema, cerebral edema.</p>';
    html += S.drugTable(
      S.drugRow('Fluids', 'Aggressive resuscitation', 'IV', 'Dehydration common. Avoid fluid overload (risk of pulmonary edema).') +
      S.drugRow('Sodium bicarb', '1-2 mEq/kg IV bolus → drip', 'IV', 'Urinary alkalinization (goal urine pH &gt;7.5). Prevents CNS entry.') +
      S.drugRow('Glucose', 'Maintain euglycemia even if BG normal', 'IV', 'CNS hypoglycemia despite normal serum glucose.') +
      S.drugRow('Hemodialysis', '—', '—', 'For severe: altered MS, pulmonary edema, renal failure, refractory acidosis, or level &gt;100 mg/dL acute / &gt;60 chronic.')
    );
  } else if (topic === 'etoh') {
    html += '<div style="padding:10px 14px;border-radius:8px;background:var(--blue-light);border:1.5px solid var(--blue);margin-bottom:10px;"><strong>Toxic alcohols (methanol / ethylene glycol)</strong></div>';
    html += '<p style="font-size:13px;">Anion gap metabolic acidosis + osmolar gap. Methanol → visual changes, blindness. Ethylene glycol → calcium oxalate crystals in urine, renal failure.</p>';
    html += S.drugTable(
      S.drugRow('Fomepizole', '15 mg/kg IV load → 10 mg/kg q12h × 4 → 15 mg/kg q12h', 'IV', 'First-line. Inhibits alcohol dehydrogenase.') +
      S.drugRow('Ethanol (alternative)', 'Load 600 mg/kg → maintain level 100-150 mg/dL', 'IV / PO', 'If fomepizole unavailable. Monitor closely.') +
      S.drugRow('Hemodialysis', '—', '—', 'For severe acidosis, end-organ damage, or high levels.') +
      S.drugRow('Folate / thiamine / pyridoxine', 'Standard doses', 'IV', 'Methanol: folate. EG: thiamine + pyridoxine (divert to non-toxic metabolites).')
    );
  } else if (topic === 'dialyzable') {
    html += '<div style="padding:10px 14px;border-radius:8px;background:var(--blue-light);border:1.5px solid var(--blue);margin-bottom:10px;"><strong>Dialyzable drugs (ISTUMBLE)</strong></div>';
    html += '<p style="font-size:13px;">Commonly dialyzable in overdose:</p>';
    html += '<div style="display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:6px;font-size:13px;">';
    [['I','Isopropyl alcohol, INH'],['S','Salicylates'],['T','Theophylline, Toxic alcohols'],['U','Uremia-related drugs'],['M','Methanol, Metformin, Methotrexate'],['B','Barbiturates (long-acting)'],['L','Lithium'],['E','Ethylene glycol']].forEach(function(x) {
      html += '<div style="padding:8px 10px;background:var(--g50);border-radius:6px;"><strong>' + x[0] + ':</strong> ' + x[1] + '</div>';
    });
    html += '</div>';
    html += '<div style="padding:10px;background:#fef3c7;border-radius:6px;font-size:12px;color:#92400e;margin-top:10px;"><strong>Poor candidates for HD:</strong> Large Vd (TCAs, digoxin, BBs), highly protein-bound (benzos, CCBs), lipid-soluble (opioids, phenothiazines). EXTRIP recommendations are evidence-based — consult toxicology.</div>';
  }
  html += S.ref('Call Poison Control early: 1-800-222-1222 (US). Refs: Goldfrank\'s Toxicologic Emergencies, EXTRIP workgroup.');
  el.innerHTML = html;
}

export function init() {
  document.addEventListener('click', function(e) {
    if (e.target.id === 'btn-tox-lookup' || e.target.closest('#btn-tox-lookup')) lookupTox();
  });
}