// ============================================================
// bedside/neonatal.js
// NEONATAL ASSESSMENT (Fenton growth) + NRP pathway + Apgar.
// ============================================================
import { S } from './shared.js';
// Fenton 2013 LMS data (weight in grams, GA in weeks).
//
// LMS parameters derived empirically from peditools.org/fenton2013 —
// peditools is widely used and consistent with the published
// Fenton TR, Kim JH. BMC Pediatrics 2013;13:59 reference. Each week's
// triple was fit against 6 probe weights per week (RMSE < 0.005 z-score
// units). Replaces an earlier hand-rounded table whose z-scores drifted
// ~0.05 SD from peditools/Epic near term — that drift was enough to push
// borderline infants across SGA/AGA cutoffs.
//
// Validated test cases:
// 40 5/7 wk male, 3070g → z = -1.42 (Epic: -1.43, peditools: -1.42)
var fentonLMS = {
male: {
22:{L:0.5885,M:496,S:0.12802},23:{L:0.7565,M:571,S:0.14547},24:{L:0.9128,M:651,S:0.16235},25:{L:1.0544,M:741,S:0.17765},
26:{L:1.1862,M:841,S:0.19029},27:{L:1.3051,M:953,S:0.19989},28:{L:1.3699,M:1079,S:0.20777},29:{L:1.4165,M:1223,S:0.21163},
30:{L:1.4172,M:1388,S:0.21185},31:{L:1.3755,M:1578,S:0.20785},32:{L:1.2952,M:1790,S:0.20112},33:{L:1.1974,M:2018,S:0.19143},
34:{L:1.0743,M:2255,S:0.18119},35:{L:0.9583,M:2493,S:0.16992},36:{L:0.8460,M:2726,S:0.16001},37:{L:0.7543,M:2947,S:0.15072},
38:{L:0.6650,M:3156,S:0.14304},39:{L:0.5881,M:3360,S:0.13641},40:{L:0.5237,M:3568,S:0.13173},41:{L:0.4691,M:3785,S:0.12863},
42:{L:0.4216,M:4014,S:0.12735}
},
female: {
22:{L:-0.0868,M:481,S:0.13605},23:{L:0.2119,M:537,S:0.14635},24:{L:0.5281,M:606,S:0.16134},25:{L:0.8258,M:694,S:0.18077},
26:{L:1.0501,M:792,S:0.19889},27:{L:1.2084,M:899,S:0.21323},28:{L:1.2599,M:1017,S:0.22437},29:{L:1.2539,M:1152,S:0.22982},
30:{L:1.2262,M:1306,S:0.23082},31:{L:1.1223,M:1482,S:0.22733},32:{L:1.0122,M:1681,S:0.21846},33:{L:0.8746,M:1897,S:0.20681},
34:{L:0.7299,M:2126,S:0.19407},35:{L:0.5929,M:2362,S:0.18059},36:{L:0.4534,M:2602,S:0.17028},37:{L:0.3462,M:2835,S:0.16139},
38:{L:0.2636,M:3050,S:0.15513},39:{L:0.2069,M:3239,S:0.15004},40:{L:0.1670,M:3415,S:0.14649},41:{L:0.1517,M:3596,S:0.14359},
42:{L:0.1308,M:3787,S:0.14127}
}
};
function interpolateLMS(table, val) {
var keys = Object.keys(table).map(Number).sort(function(a,b){return a-b;});
if (val <= keys[0]) return table[keys[0]];
if (val >= keys[keys.length-1]) return table[keys[keys.length-1]];
for (var i = 0; i < keys.length - 1; i++) {
if (val >= keys[i] && val <= keys[i+1]) {
var t = (val - keys[i]) / (keys[i+1] - keys[i]);
var a = table[keys[i]], b = table[keys[i+1]];
return { L: a.L + t*(b.L-a.L), M: a.M + t*(b.M-a.M), S: a.S + t*(b.S-a.S) };
}
}
return table[keys[0]];
}
function calcZ(value, L, M, S) {
if (Math.abs(L) < 0.001) return Math.log(value / M) / S;
return (Math.pow(value / M, L) - 1) / (L * S);
}
function zToPercentile(z) {
// Approximation of the standard normal CDF
var a1=0.254829592, a2=-0.284496736, a3=1.421413741, a4=-1.453152027, a5=1.061405429, p=0.3275911;
var sign = z < 0 ? -1 : 1;
var x = Math.abs(z) / Math.sqrt(2);
var t = 1 / (1 + p * x);
var y = 1 - (((((a5*t + a4)*t) + a3)*t + a2)*t + a1)*t * Math.exp(-x*x);
return Math.round(((1 + sign * y) / 2) * 1000) / 10;
}
function classifyGA(weeks, days) {
var total = weeks + (days || 0) / 7;
if (total < 28) return { label: 'Extremely Preterm', color: '#dc2626', icon: 'fa-triangle-exclamation' };
if (total < 32) return { label: 'Very Preterm', color: '#ea580c', icon: 'fa-triangle-exclamation' };
if (total < 34) return { label: 'Moderate Preterm', color: '#d97706', icon: 'fa-circle-exclamation' };
if (total < 37) return { label: 'Late Preterm', color: '#ca8a04', icon: 'fa-circle-info' };
if (total < 39) return { label: 'Early Term', color: '#2563eb', icon: 'fa-circle-info' };
if (total < 41) return { label: 'Full Term', color: '#16a34a', icon: 'fa-circle-check' };
if (total < 42) return { label: 'Late Term', color: '#d97706', icon: 'fa-circle-info' };
return { label: 'Post Term', color: '#dc2626', icon: 'fa-triangle-exclamation' };
}
function classifyWeight(percentile) {
if (percentile < 3) return { label: 'Severely SGA', color: '#dc2626', detail: '<3rd percentile' };
if (percentile < 10) return { label: 'SGA', color: '#ea580c', detail: '<10th percentile' };
if (percentile > 97) return { label: 'Severely LGA', color: '#dc2626', detail: '>97th percentile' };
if (percentile > 90) return { label: 'LGA', color: '#ea580c', detail: '>90th percentile' };
return { label: 'AGA', color: '#16a34a', detail: '10th-90th percentile' };
}
function classifyBirthWeight(grams) {
if (grams < 1000) return { label: 'Extremely Low Birth Weight (ELBW)', color: '#dc2626' };
if (grams < 1500) return { label: 'Very Low Birth Weight (VLBW)', color: '#ea580c' };
if (grams < 2500) return { label: 'Low Birth Weight (LBW)', color: '#d97706' };
if (grams <= 4000) return { label: 'Normal Birth Weight', color: '#16a34a' };
return { label: 'Macrosomia (>4000g)', color: '#ea580c' };
}
function neoAssess() {
var weeks = parseInt(document.getElementById('neo-ga-weeks').value);
var days = parseInt(document.getElementById('neo-ga-days').value) || 0;
var weight = parseFloat(document.getElementById('neo-weight').value);
var sex = document.getElementById('neo-sex').value;
var resultDiv = document.getElementById('neo-result');
if (!weeks || !weight) {
resultDiv.innerHTML = 'Enter GA and birth weight.
';
return;
}
var gaDecimal = weeks + days / 7;
var gaClass = classifyGA(weeks, days);
var bwClass = classifyBirthWeight(weight);
// Calculate percentile using Fenton LMS
var lms = interpolateLMS(fentonLMS[sex], gaDecimal);
var z = calcZ(weight, lms.L, lms.M, lms.S);
var percentile = zToPercentile(z);
var wtClass = classifyWeight(percentile);
var expectedWeight = Math.round(lms.M);
var html = '';
// GA Classification
html += '';
html += '
';
html += '
Gestational Age Classification
';
html += '
' + gaClass.label + '
';
html += '
' + weeks + ' weeks ' + days + ' days (' + gaDecimal.toFixed(1) + ' weeks)
';
html += '
';
// Weight Classification (AGA/SGA/LGA)
html += '
';
html += '
Weight for Gestational Age
';
html += '
' + wtClass.label + '
';
html += '
' + percentile.toFixed(1) + 'th percentile (' + wtClass.detail + ')
';
html += '
';
html += '
';
html += '
';
html += '
Birth Weight Category
';
html += '
' + bwClass.label + '
';
html += '
' + weight + 'g (' + (weight/1000).toFixed(2) + ' kg)
';
html += '
';
// Stats
html += '
';
html += '
Fenton Growth Data (' + (sex === 'male' ? 'Male' : 'Female') + ')
';
html += '
';
html += 'Expected weight (50th %ile): ' + expectedWeight + 'g
';
html += 'Z-score: ' + z.toFixed(2) + '
';
html += 'Percentile: ' + percentile.toFixed(1) + '%';
html += '
';
html += '
Fenton TR, Kim JH. A systematic review and meta-analysis to revise the Fenton growth chart for preterm infants. BMC Pediatrics 2013;13:59. GA classification per ACOG/AAP definitions.
';
resultDiv.innerHTML = html;
}
// ---- NRP pathway + drug calc -----------------------------------------
function renderPathway() {
var el = document.getElementById('nrp-pathway-static');
if (!el || el.dataset.rendered) return;
var html = '';
html += S.stepBox('#3b82f6', 'BIRTH — ASSESS (first 30 sec)', 'Term? Tone? Breathing/crying? If all yes → routine care with mother. If any no → warm, dry, stimulate, position airway, clear airway PRN, evaluate HR & respirations.');
html += S.arrow;
html += S.stepBox('#8b5cf6', 'HR < 100 OR apneic/gasping (60 sec)', 'Start PPV 40-60 breaths/min, room air for term / 21-30% for preterm. Attach SpO2 (right hand) ± ECG. MR SOPA if ineffective: Mask adjust, Reposition, Suction, Open mouth, Pressure increase, Alternative airway.');
html += S.arrow;
html += S.stepBox('#f59e0b', 'HR < 100 after 30 sec effective PPV', 'Reassess ventilation — ensure chest rise. Consider increasing FiO2, intubation, or LMA. Continue PPV.');
html += S.arrow;
html += S.stepBox('#ef4444', 'HR < 60 after 30 sec of effective PPV', 'Intubate + Chest compressions — 3:1 ratio (90 compressions + 30 breaths per minute), FiO2 100%, lower 1/3 sternum, depth 1/3 AP chest.');
html += S.arrow;
html += S.stepBox('#dc2626', 'HR < 60 despite compressions + PPV x 60 sec', 'Epinephrine 1:10,000 (0.1 mg/mL):
• IV/IO: 0.01-0.03 mg/kg (0.1-0.3 mL/kg) — preferred
• ETT: 0.05-0.1 mg/kg (0.5-1 mL/kg) — while IV being placed
Repeat q3-5 min. If hypovolemia: NS 10 mL/kg IV/IO over 5-10 min.');
html += '';
html += '
Target SpO2 (preductal):
1 min: 60-65%
2 min: 65-70%
3 min: 70-75%
4 min: 75-80%
5 min: 80-85%
10 min: 85-95%
';
html += '
Initial ETT size:
<1 kg / <28 wk: 2.5
1-2 kg / 28-34 wk: 3.0
2-3 kg / 34-38 wk: 3.5
>3 kg / >38 wk: 3.5-4.0
';
html += '
ETT depth (lip):
~ 6 + weight(kg) cm
';
html += '
Enter weight (kg).
'; return; }
var epiIvLow = Math.round(wt * 0.01 * 100) / 100;
var epiIvHigh = Math.round(wt * 0.03 * 100) / 100;
var epiEtLow = Math.round(wt * 0.05 * 100) / 100;
var epiEtHigh = Math.round(wt * 0.1 * 100) / 100;
var ns = Math.round(wt * 10);
var d10 = Math.round(wt * 2 * 10) / 10;
var html = 'NRP doses — ' + wt + ' kg
';
var pk = function(txt) { return ' (' + txt + ')'; };
html += S.drugTable(
S.drugRow('Epinephrine 1:10,000', epiIvLow + '-' + epiIvHigh + ' mg, ' + (Math.round(epiIvLow*10)/10) + '-' + (Math.round(epiIvHigh*10)/10) + ' mL' + pk('0.01-0.03 mg/kg = 0.1-0.3 mL/kg'), 'IV / IO', 'Preferred route. Repeat q3-5 min.') +
S.drugRow('Epinephrine 1:10,000', epiEtLow + '-' + epiEtHigh + ' mg, ' + (Math.round(epiEtLow*10)/10) + '-' + (Math.round(epiEtHigh*10)/10) + ' mL' + pk('0.05-0.1 mg/kg = 0.5-1 mL/kg'), 'ETT', 'While IV being placed.') +
S.drugRow('Normal saline', ns + ' mL' + pk('10 mL/kg'), 'IV / IO', 'Over 5-10 min for volume. Repeat PRN.') +
S.drugRow('Dextrose 10%', d10 + ' mL' + pk('2 mL/kg = 0.2 g/kg'), 'IV slow push', 'For documented hypoglycemia. Then D10 infusion 4-6 mg/kg/min.')
);
html += 'Concentration note: NRP uses epinephrine 1:10,000 (0.1 mg/mL). NOT 1:1000 (1 mg/mL) — that is IM for anaphylaxis / older patients.
';
html += S.ref('AHA/AAP Neonatal Resuscitation Program (NRP) 8th edition, 2020.');
el.innerHTML = html;
}
// ---- Apgar -----------------------------------------------------------
function calcApgar() {
var keys = ['appearance','pulse','grimace','activity','respiration'];
var total = keys.reduce(function(s, k) {
return s + (parseInt(document.getElementById('apgar-' + k).value) || 0);
}, 0);
var el = document.getElementById('apgar-result');
var color, severity, guidance;
if (total >= 7) {
color = '#10b981'; severity = 'Reassuring';
guidance = 'Routine newborn care. Continue reassessment. Repeat at 5 min.';
} else if (total >= 4) {
color = '#f59e0b'; severity = 'Moderately depressed';
guidance = 'Stimulate, clear airway, warm. Give O2 if cyanotic. Ventilate with PPV if HR <100 or apneic/gasping. Reassess q30 sec.';
} else {
color = '#ef4444'; severity = 'Severely depressed';
guidance = 'Full NRP pathway — PPV immediately. Intubate if PPV ineffective. Chest compressions if HR <60. Epinephrine and volume per NRP.';
}
var html = '';
html += '
Apgar: ' + total + '/10 — ' + severity + '';
html += '
' + guidance + '
Apgar is a description of status — never delay resuscitation while scoring. Follow NRP algorithm based on HR and breathing. Apgar <7 at 5 min: repeat q5 min up to 20 min.
';
el.innerHTML = html;
}
export function init() {
// Neonatal assessment
document.addEventListener('click', function(e) {
if (e.target.id === 'btn-neo-assess' || e.target.closest('#btn-neo-assess')) neoAssess();
});
// NRP pathway render + calc
document.addEventListener('DOMContentLoaded', renderPathway);
document.addEventListener('tabChanged', function() { setTimeout(renderPathway, 100); });
if (document.readyState !== 'loading') setTimeout(renderPathway, 0);
document.addEventListener('click', function(e) {
if (e.target.id === 'btn-nrp-calc' || e.target.closest('#btn-nrp-calc')) calcNRP();
// Render NRP pathway when Neonatal sub-pill is clicked (in case component loaded late)
var np = e.target.closest && e.target.closest('[data-em="neonatal"]');
if (np) setTimeout(renderPathway, 0);
var nav = e.target.closest && e.target.closest('[data-calc="bedside"]');
if (nav) setTimeout(renderPathway, 50);
});
// Apgar
document.addEventListener('click', function(e) {
if (e.target.id === 'btn-apgar-calc' || e.target.closest('#btn-apgar-calc')) calcApgar();
});
}