Bedside Action Box — Suspected Critical CHD in the First Hour
Call for senior help first — do not act alone
- Call: senior neonatologist, cardiology, cardiac transport/center, respiratory therapy, nursing lead, pharmacy.
- Assess: right-hand and lower-limb SpO₂; 4-extremity BPs; pulses; perfusion; blood gas with lactate; glucose; calcium; CBC; blood culture if infection possible; CXR as needed.
- Start prostaglandin if cyanosis, shock, weak femoral pulses, metabolic acidosis, or uncertain ductal-dependent physiology — while arranging urgent echo and transfer.
- Avoid reflex high O₂ in lesions with pulmonary overcirculation. Titrate O₂ to physiology and cardiology guidance.
- Secure access: umbilical venous and arterial lines are preferred when the infant is unstable or likely to need surgery/catheterization.
- Reassess every 15–30 minutes: work of breathing, pulses, perfusion, urine output, lactate trend, pre/postductal saturation pattern, and response to PGE or ventilation changes.
1. Overview
Congenital heart disease in the newborn is best approached by physiology rather than by memorizing lesion names. The immediate bedside question is: does the baby have inadequate mixing, inadequate pulmonary blood flow, excessive pulmonary blood flow, ductal-dependent systemic blood flow, myocardial dysfunction, arrhythmia, or a non-cardiac mimic?
Serious lesions often present during the first days of life as the ductus arteriosus constricts and pulmonary vascular resistance falls. Some infants look stable at birth, then develop cyanosis, respiratory distress, poor feeding, weak pulses, acidosis, oliguria, or shock hours to weeks later.
Safest initial approach
- Stabilize oxygen delivery and protect systemic perfusion
- Use prostaglandin early when ductal dependence is possible
- Obtain echocardiography urgently
- Communicate with a cardiac center before the infant deteriorates
2. Why This Topic Matters
| Problem | Why It Matters at Bedside | Immediate Implication |
|---|
| Clinical signs may be subtle | A critical lesion may have no loud murmur and may pass an early exam | Use pulse oximetry screening, repeated perfusion exams, pulses, and low threshold for echo |
| Ductal closure changes physiology | Systemic or pulmonary blood flow can collapse as the duct constricts | Start prostaglandin when symptomatic ductal-dependent physiology is possible |
| Oxygen can help or harm | Oxygen decreases PVR and can worsen pulmonary overcirculation in some mixing/systemic-flow lesions | Treat saturations according to lesion physiology, not a fixed normal newborn target |
| Shock may be mistaken for sepsis | Coarctation, interrupted arch, HLHS, critical AS, myocarditis, and sepsis can present similarly | Treat sepsis if possible, but do not delay prostaglandin and echo in a shocked neonate |
| Preterm infants with CHD are fragile | Immature myocardium, brain, gut, lungs, and thermal control reduce reserve | Trend lactate, renal output, respiratory load, nutrition, and surgical timing closely |
3. Recognition: When to Suspect CHD
Evaluate for CHD when any of the following are present: failed or borderline CCHD screen, persistent central cyanosis, differential cyanosis, shock without a clear cause, weak or absent femoral pulses, unexplained metabolic acidosis, tachypnea without lung findings, recurrent hypoxemia, pathologic murmur, abnormal fetal echo, dysmorphic features, or a family history/syndrome associated with CHD.
| Cardinal Sign | Cardiac Clues | Important Mimics |
|---|
| Cyanosis |
Central cyanosis; low right-hand or lower-limb saturation; poor response to O₂; differential or reverse differential cyanosis; single loud S2; minimal lung disease on exam or CXR |
PPHN, pneumonia, RDS, MAS, hypothermia, polycythemia, methemoglobinemia, sepsis, airway disease |
| Systemic hypoperfusion |
Weak femoral pulses, upper-lower BP gradient, narrow pulse pressure, oliguria, metabolic acidosis, gray color, hepatomegaly, shock after several hours/days |
Sepsis, hypovolemia, adrenal insufficiency, anemia, metabolic disease, arrhythmia, tamponade |
| Tachypnea / heart failure |
Tachypnea with mild/no cyanosis, feeding fatigue, diaphoresis, hepatomegaly, pulmonary edema, hyperdynamic precordium, wide pulse pressure |
TTN, pneumonia, BPD, anemia, aspiration, pulmonary hemorrhage |
4. Initial Bedside Evaluation
| Domain | What to Do | Interpretation |
|---|
| History |
Fetal echo, anatomic scan, family CHD, genetic diagnosis, maternal diabetes, anticonvulsant/lithium exposure, infection risk, delivery course, Apgars, resuscitation, age at symptom onset |
Prenatal suspicion should trigger a delivery-room plan before clinical deterioration |
| Inspection |
Central cyanosis, respiratory distress, gray color, diaphoresis, poor activity, hepatomegaly, edema, dysmorphism, perfusion under adequate light |
A calm baby with severe cyanosis and little respiratory distress is concerning for cardiac disease or PPHN |
| Pulse oximetry |
Measure right hand and either foot simultaneously when possible; trend rather than relying on one number |
Preductal > postductal suggests R→L ductal shunt; lower preductal than postductal can occur in TGA with arch obstruction or suprasystemic pulmonary pressure |
| Pulses and 4-limb BP |
Palpate brachial/femoral pulses; obtain 4-extremity BP on admission or if arch obstruction is possible |
A gradient supports arch obstruction, but a wide-open duct can mask coarctation. Normal 4-limb BP does not exclude arch disease. |
| Blood gas/lactate |
Arterial or well-collected sample for pH, PaCO₂, PaO₂, lactate, glucose, ionized calcium, Hb/Hct |
Rising lactate or worsening base deficit = O₂ delivery is failing, even if BP is acceptable |
| ECG/CXR |
ECG for rhythm, axis, chamber hypertrophy; CXR for heart size, pulmonary vascularity, edema, situs, lung disease |
Normal ECG does not exclude CHD. CXR can suggest pulmonary blood flow category but does not define anatomy. |
| Echocardiography |
Urgent echo for symptomatic cyanosis, shock, abnormal screen without explanation, suspected ductal dependence, or uncertain physiology |
Echo defines anatomy, shunts, ductal direction, atrial restriction, ventricular function, pulmonary pressure, and surgical/cath pathway |
5. CCHD Pulse-Oximetry Screening
Symptomatic infants bypass the screening algorithm entirely
Screening is for apparently well infants before discharge. A symptomatic infant should not wait for a screening protocol — evaluate and stabilize immediately.
| Screening Situation | Practical Approach | Action |
|---|
| Routine well newborn |
Perform right-hand and foot SpO₂ at ≥24 hours of age, or as late as possible before earlier discharge |
Use the local/national algorithm; document preductal and postductal values |
| US AAP/CDC updated approach (2024/2025) |
Pass requires BOTH preductal and postductal ≥95% with acceptable difference; indeterminate results retested once per protocol |
Failed or persistent borderline screen → urgent clinical assessment and usually echo if no non-cardiac explanation |
| UK/West Midlands approach |
Similar but not identical thresholds; includes action bands for <90%, 90–94%, or abnormal pre/postductal difference |
Follow local policy; do not mix algorithms on the same patient |
| NICU infant on supplemental O₂ |
Screen after O₂ is discontinued when clinically appropriate, unless symptoms already require diagnostic evaluation |
Persistent hypoxemia requires diagnostic workup, not only a screening repeat |
Important limitation of pulse oximetry screening
Screening improves early detection but does not detect all critical lesions. Coarctation and interrupted arch may be missed, especially while the ductus is open. Persistent poor pulses, acidosis, poor feeding, or shock require urgent echo even after a passed screen.
6. Physiology-Based Classification
| Physiology Group | Common Lesions | Expected Bedside Pattern | Initial Stabilization Priority |
|---|
| Separate/parallel circulations — poor mixing |
D-TGA ± VSD; Taussig-Bing/DORV with subpulmonary VSD |
Severe cyanosis, often little respiratory distress; saturation may remain low despite O₂; lactate rises if mixing is inadequate |
Start PGE₁; assess atrial communication urgently; prepare for balloon atrial septostomy if restrictive mixing |
| Ductal-dependent pulmonary blood flow |
Critical pulmonary stenosis; pulmonary atresia/IVS; tricuspid atresia; severe TOF/TOF with PA; Ebstein anomaly; single ventricle with PS |
Cyanosis worsens as duct closes; decreased pulmonary vascular markings; saturations often lower than normal |
Start PGE₁; avoid unnecessary high O₂ if stable; target adequate O₂ delivery and lactate rather than normal saturation |
| Complete mixing — normal/increased pulmonary blood flow |
TAPVC, truncus arteriosus, single ventricle without PS, DORV without PS, large AVSD/VSD physiology |
Mild-moderate cyanosis or normal sats; tachypnea/heart failure as PVR falls; pulmonary congestion; wide pulse pressure in truncus/large PDA |
Avoid excessive O₂/alkalosis when overcirculation threatens systemic flow; support ventilation; diurese if needed; cardiology/surgery plan |
| Ductal-dependent systemic blood flow |
HLHS, critical AS, severe coarctation, interrupted aortic arch, Shone complex/left heart obstruction |
Shock, weak femoral pulses, metabolic acidosis, oliguria, poor perfusion, sometimes mild/no cyanosis; decompensation often after ductal constriction |
Start PGE₁ immediately; support systemic perfusion; cautious volume; avoid lowering PVR too much; urgent echo/transfer |
| Large left-to-right shunt / acyanotic heart failure |
Large VSD, AVSD, PDA, aortopulmonary window, large ASD + another lesion |
Symptoms increase as PVR falls: tachypnea, feeding fatigue, pulmonary edema, hepatomegaly, growth failure |
Optimize nutrition/respiratory support; consider diuretics; avoid excess O₂ if overcirculation; plan timing of repair |
7. Lesion-Specific Bedside Notes
| Lesion / Group | High-Yield Physiology | What the NICU Team Must Not Miss |
|---|
| D-TGA |
Parallel circuits; survival depends on atrial, ductal, or ventricular mixing. Atrial mixing is often most important. |
Start PGE₁. If severe cyanosis/acidosis persists, urgent balloon atrial septostomy. Do not assume O₂ failure is lung disease. |
| TAPVC |
Pulmonary venous blood returns abnormally and must cross an ASD. Obstructed TAPVC causes pulmonary venous HTN, edema, and profound hypoxemia. |
Obstructed TAPVC is a surgical emergency. PGE₁ usually does not fix the problem. Look for pulmonary edema with severe cyanosis. |
| Truncus arteriosus |
One arterial trunk supplies both circuits; as PVR falls, pulmonary overcirculation steals systemic output. |
Avoid excessive O₂ and hyperventilation. Monitor diastolic BP, coronary/systemic perfusion, calcium, and 22q11 risk. |
| TOF spectrum |
Degree of RV outflow obstruction determines cyanosis. Severe obstruction makes pulmonary blood flow ductal-dependent. |
For hypercyanotic spells: calm/sedate, knee-chest position, volume if depleted, raise SVR, consider beta blockade, call cardiology. |
| Pulmonary atresia/IVS |
Pulmonary blood flow is ductal-dependent; RV size and coronary anatomy determine pathway. |
Maintain ductal patency. RV-dependent coronary circulation must be recognized before interventions. |
| Ebstein anomaly |
Atrialized RV, severe tricuspid regurgitation, functional pulmonary atresia, massive cardiomegaly may occur. |
Cyanosis may improve as PVR falls, but severe cases need PGE₁, respiratory/circulatory support, and cardiology/surgical planning. |
| HLHS / critical left heart obstruction |
Systemic blood flow depends on R→L ductal flow; pulmonary overcirculation can reduce systemic O₂ delivery. |
Start PGE₁; monitor lactate/NIRS/UO; avoid excess O₂; maintain balanced Qp:Qs; secure access. |
| Coarctation / interrupted arch |
Ductal flow may mask gradient early; closure causes lower-body hypoperfusion and shock. |
Normal early exam does not exclude coarctation. Watch femoral pulses, 4-limb BP, lactate, renal output. Start PGE₁ if symptomatic. |
| Large VSD/AVSD/PDA/AP window |
Pulmonary overcirculation develops as PVR falls; heart failure often delayed beyond newborn period. |
Manage respiratory load and nutrition; diuretics may help symptoms. Normal SpO₂ does not mean the lesion is benign. |
8. Initial Stabilization Algorithm
CHD — Initial Stabilization Steps
STEP 1 — Recognize
Cyanosis · shock · weak pulses · acidosis · abnormal screen · fetal CHD · unexplained tachypnea
Do not wait for a murmur — many critical lesions have no diagnostic murmur at presentation
↓
STEP 2 — Stabilize ABC
Warmth · airway positioning · ventilation if apnea/fatigue · glucose/calcium correction · vascular access · sepsis evaluation if indicated
Correct reversible O₂-delivery problems while preserving cardiac physiology
↓
STEP 3 — Measure physiology
R-hand + foot SpO₂ · 4-limb BP · ABG/lactate · CXR · ECG · perfusion + UO · urgent echo
Single values are less useful than pattern and trend
↓
STEP 4 — Start PGE₁ when indicated
Symptomatic ductal-dependent pulmonary/systemic flow · severe unexplained cyanosis · shock suggesting ductal closure
Do not delay for transfer or echo if the baby is unstable and ductal dependence is plausible
↓
STEP 5 — Choose saturation strategy by physiology
Pulmonary flow obstruction: SpO₂ 75–85% may be acceptable if lactate/perfusion reassuring
Systemic-flow lesions: balanced Qp:Qs — chasing 100% can worsen pulmonary steal
↓
STEP 6 — Consult and transfer
Call cardiology/cardiac ICU/transport early; share vitals · gases · lactate · echo (if available) · PGE dose · access · airway status · response
Delayed transfer after acidosis or shock increases perioperative risk
| Step | Action | Rationale / Warning |
|---|
| Recognize | Cyanosis, shock, weak pulses, acidosis, abnormal screen, fetal CHD, or unexplained tachypnea | Do not wait for a murmur; many critical lesions have no diagnostic murmur at presentation |
| Stabilize ABC | Warmth, airway, ventilation if apnea/fatigue, glucose/calcium, vascular access, sepsis evaluation if indicated | Correct reversible O₂-delivery problems while preserving cardiac physiology |
| Measure physiology | R-hand and foot SpO₂; 4-limb BP; ABG/lactate; CXR; ECG; perfusion; UO; urgent echo | Single values are less useful than pattern and trend |
| Start PGE₁ when indicated | Symptomatic ductal-dependent pulmonary/systemic flow, severe unexplained cyanosis, or shock suggesting ductal closure | Do not delay for transfer or echo if ductal dependence is plausible |
| Choose saturation strategy | Pulmonary flow obstruction may tolerate 75–85% if lactate/perfusion are adequate; systemic-flow lesions need balanced Qp:Qs | Chasing 100% saturation can worsen pulmonary steal in some lesions |
| Consult and transfer | Call cardiology/cardiac ICU/transport early; share vitals, gases, lactate, echo if available, PGE dose, access, airway, response | Delayed transfer after acidosis or shock increases perioperative risk |
9. Prostaglandin for Ductal-Dependent Lesions
PGE₁ is a stabilizing bridge, not definitive treatment
It maintains or reopens ductal patency for lesions dependent on ductal flow for pulmonary blood flow, systemic blood flow, or intercirculatory mixing.
| Clinical Situation | Use of PGE₁ | Response to Monitor |
|---|
| Known antenatal ductal-dependent lesion, stable newborn | Start at center-specific low dose recommended by cardiology/local formulary | Stable pH/lactate, adequate perfusion, expected saturations for lesion |
| Cyanosed but well infant — suspected right-sided obstruction | Start promptly; titrate to adequate pulmonary blood flow | Improving oxygenation; commonly acceptable SpO₂ 75–85% if perfusion/lactate reassuring and cardiology agrees |
| Shock or acidosis — suspected systemic-flow obstruction | Start urgently while resuscitating and arranging echo/transport | Improved pulses, pH, lactate, UO, perfusion, lower-body blood flow |
| TGA with inadequate mixing | Start PGE₁ but recognize it may not be enough if atrial septum is restrictive | If saturation/lactate remain poor, urgent balloon atrial septostomy is likely needed |
| Pulmonary overcirculation lesion without ductal need | May worsen systemic perfusion by lowering PVR and promoting run-off | Use only after cardiology/echo confirms benefit or arch obstruction coexists |
PGE₁ Adverse Effects and Bedside Management
| Adverse Effect / Issue | What to Anticipate | Bedside Response |
|---|
| Apnea | More likely in preterm infants and with higher doses; may occur after starting or increasing infusion | Continuous monitoring; prepare airway support — especially for transport or unstable infants |
| Hypotension / flushing / fever | Systemic vasodilation and temperature instability | Monitor BP/perfusion; cautious fluid if hypovolemic; vasoactive support if needed |
| Overcirculation | Lower PVR can increase pulmonary blood flow at the expense of systemic flow | Trend lactate, diastolic BP, renal output, NIRS if available, respiratory status |
| Line safety | Short half-life means interruption can rapidly destabilize the infant | Reliable pump; dedicated line when possible; backup access; clear handoff during transport |
| Formulary variation | US uses alprostadil/PGE₁; some UK pathways use dinoprostone/PGE₂ with local preparation | Verify drug, concentration, dose range, compatibility, and transport policy locally |
9+. The Arch Watch Protocol and PGE Response (Baylor Ed. 33)
A newborn with suspected arch obstruction is the commonest reason an otherwise well-looking baby is admitted and watched. The protocol turns on a single number: the upper-to-lower-extremity systolic gradient.
| Situation | What to do |
|---|
| Low prenatal suspicion, pulses easily palpable, normal heart and respiratory rate, and a BP gradient under 20 mmHg |
Observe with four-extremity blood pressures every 6 hours; serial labs may not be needed. Consult cardiology and obtain an echocardiogram. |
| High prenatal suspicion, or a gradient above 20 mmHg, or any abnormal vital sign |
Urgent cardiology consult; order PGE to the bedside if it is not already running; consider central venous and arterial access for frequent labs; obtain the echocardiogram urgently. |
Two associations not to miss
- Coarctation in a female → consider Turner syndrome.
- Interrupted aortic arch → screen for 22q11 deletion (DiGeorge); the association is roughly 50%. Check the ionized calcium.
- A normal newborn may have up to a 15 mmHg systolic gradient between upper and lower limbs — that alone is not coarctation. Cuff pressures are also distorted by distress and agitation, so they monitor change better than they diagnose.
How PGE actually behaves
- Response is judged within about 30 minutes — a rising pH in an acidotic infant, or a rising PaO₂.
- PGE lowers both resistances but lowers pulmonary resistance more than systemic, so it can tip an at-risk infant into pulmonary overcirculation. In truncus arteriosus and similar complete-mixing lesions without obstruction, PGE is usually unhelpful and may worsen systemic perfusion unless coarctation or an interrupted arch is also present.
- Response depends on how long the duct has been closed. Cyanosis usually appears soon after closure, so those infants respond well. Do not assume an infant presenting at several weeks is unresponsive — especially a preterm infant, whose recently closed duct may still open.
- Coarctation is the lesion most likely to fail PGE: these infants can survive days on marginal flow, then decompensate, and often need urgent surgery regardless.
- Apnoea is the adverse effect that catches people out — commonest in preterm infants and at higher doses, but it occurs in term infants too and can begin several hours after starting. Use the lowest effective dose. Whether caffeine helps PGE-induced apnoea has not been studied. Other effects: hypotension, fever, flushing, and with long infusions electrolyte disturbance, hyperostosis and gastric outlet obstruction.
- A long infusion is legitimate — it buys lung maturation and nutrition in a preterm or SGA infant, and the risk of pulmonary vascular disease developing within a few months is small.
10. General NICU Care of Neonates With CHD
Monitoring cadence and access rules Baylor specifies
- Four-extremity blood pressures on admission for every patient, and regularly in anyone suspected of arch hypoplasia. During stable periods, an upper-extremity cuff pressure every 3 hours; continuous arterial pressure during instability or changing physiology.
- Multi-site NIRS — cerebral and somatic — considered at admission.
- Lactate by arterial puncture or indwelling line. Capillary samples may be trended but are not diagnostic.
- Umbilical arterial and venous access at delivery or admission for infants with unclear physiology or expected surgery in the first week; PICC if a UVC cannot be placed. Keep a peripheral IV after central lines come out — PGE, adenosine, vasoactives and volume may be needed without warning.
- No right-arm arterial line before HLHS stage I, in an interrupted arch awaiting advancement, or in a coarctation planned for thoracotomy — that site is likely needed for surgery.
- Low ambient lighting is normal NICU practice but hides colour and perfusion — assess appearance under proper light regularly.
- Routine head and renal ultrasound is not indicated in the absence of additional anomalies.
| Care Domain | Guideline Approach | Practical Cautions |
|---|
| Environment and O₂ demand | Maintain normothermia, minimize agitation, treat pain, cluster care, use developmentally appropriate comfort measures | Fever, cold stress, pain, seizures, and high work of breathing all increase O₂ consumption |
| Monitoring | Continuous SpO₂, cardiorespiratory monitoring, frequent perfusion exam, BP, UO, lactate trend, renal function, electrolytes; cerebral/somatic NIRS in critical lesions | BP alone is not enough — normal BP can coexist with inadequate systemic O₂ delivery |
| Vascular access | UVC/UAC for unstable or likely early-surgery infants; maintain backup peripheral IV after central line removal | Avoid right-arm arterial line when that arm may be needed for arch/coarctation surgery — confirm with surgical team |
| Nutrition | Start dextrose IV until physiology and surgical plan are clarified. Use TPN for prolonged NPO or ductal-dependent infants. Prefer human milk when feeding is allowed. | Systemic-flow lesions have mesenteric hypoperfusion risk. Advance feeds slowly; pause during PGE trial off or clinical instability. |
| Respiratory support | Reduce work of breathing while avoiding atelectasis and hyperinflation; positive pressure can reduce LV afterload but may reduce venous return/RV output | O₂ and ventilation targets must match the lesion — avoid unnecessary hyperoxia in balanced or overcirculation physiology |
| Prematurity | Expect lower reserve, earlier pulmonary overcirculation, feeding intolerance, IVH/NEC risk, and delayed surgery decisions | Daily trend: growth, lactate, respiratory support, perfusion, central line exposure, and infection risk |
| Genetics and screening | Consider genetics for CHD, especially arch lesions, conotruncal lesions, dysmorphism, or extracardiac anomalies | 22q11 risk with conotruncal/arch defects; Turner consideration in females with coarctation; individualize head/renal ultrasound |
10+. Feeding Volumes, Antiplatelet Dosing and Neurodevelopmental Referral (Baylor Ed. 33)
| Group | Feeding plan with the numbers |
|---|
| PGE-dependent systemic blood flow, surgery expected within the first month | Exclusive human milk (maternal or donor), unfortified, advanced slowly to a preoperative ceiling of 40–60 mL/kg/day — these infants are at real risk of mesenteric hypoperfusion (low certainty evidence, weak recommendation). |
| PGE-dependent pulmonary blood flow | Also unfortified human milk until the need for PGE is settled, advancing by 20 mL/kg/day as tolerated; how far you advance depends on the lesion and the expected course (low quality evidence, weak recommendation). |
| Trialling off PGE | Hold feeds for the first 24–48 hours off PGE. If the infant stays haemodynamically stable, restart at the previous volume and advance per protocol. |
| While NPO | Oral care with colostrum. The microbiome evidence comes from preterm infants and has not been studied in CHD, but Baylor recommends it for ductal-dependent infants who are NPO. |
| Growth failure / overcirculation | Individualize: fortified expressed milk or 24–30 kcal/oz feeds. Watch osmolality as calories rise — hyperosmolar feeds may predispose to NEC, and cardiac infants are already at higher NEC risk from mesenteric hypoperfusion. |
| Every PGE-dependent infant | Give TPN — the raised basal metabolic rate of CHD produces negative nitrogen balance perioperatively without it. Enteral feeding during a PGE infusion has been documented as safe. |
A belief with no evidence behind it
Many clinicians treat an infant's refusal of oral feeds as an early sign of bowel hypoperfusion or ischaemia. There is no evidence supporting this, and the safety of orogastric or nasogastric feeding in these infants remains genuinely controversial. Decide on perfusion data, not on feeding behaviour.
Aspirin for stent patency
- Dose range 3–10 mg/kg/day. Aspirin irreversibly inhibits platelet aggregation for the platelet lifespan — roughly 10 days.
- Use the 81 mg chewable tablet in fractions: 20.25 mg (¼ tablet), 40.5 mg (½ tablet) or 81 mg by size.
- Do not use aspirin suspension — poor solubility gives variable dosing, and it is not available as an outpatient product.
- Absorption is inhibited or erratic when given into the jejunum or rectum.
Neurodevelopmental referral before discharge
Infants with critical heart disease have higher rates of developmental, learning and behavioural problems that are subtle and easily missed at early ages. Every infant who has had cardiac surgery or a catheter procedure at under 3 months of age should be referred to a cardiac neurodevelopmental follow-up programme, at least one week before discharge. Isolated PDA ligation is the usual exception; infants with Down syndrome are referred to a Down syndrome clinic instead. Confirm the referral pathway your own centre uses.
11. Feeding Strategy in Preoperative CHD
| Infant Group | Suggested Approach | Hold / Slow Feeds When… |
|---|
| Unclear diagnosis or unstable physiology | NPO initially; provide glucose and early parenteral nutrition if prolonged | Lactate rising, acidosis, escalating respiratory/vasoactive support, poor perfusion |
| PGE-dependent systemic blood flow | Human milk only if feeding is allowed; unfortified, slow advancement, often limited volumes per local pathway | Any sign of mesenteric hypoperfusion, NEC concern, unstable lactate, PGE trial off |
| PGE-dependent pulmonary blood flow | May feed cautiously when stable; unfortified human milk and slow advancement until course is clear | Need for escalating PGE/O₂/ventilation, acidosis, poor systemic perfusion |
| Pulmonary overcirculation / heart failure | Optimize calories carefully; may need fortification or higher-calorie feeds once safe | Tachypnea limiting oral feeding, aspiration risk, pulmonary edema, poor growth despite high work |
| Post-catheter/surgical infant | Follow cardiac center feeding pathway; assess vocal cord/airway if symptoms after arch/PDA surgery | Postoperative low CO, gut hypoperfusion, chylothorax, high vasoactive support |
12. Patent Ductus Arteriosus in Preterm Infants
PDA management in preterm infants is separate from PGE-maintained ductal-dependent CHD
The same ductus that saves a baby with HLHS or pulmonary atresia may harm an extremely preterm infant when it causes large left-to-right shunting, pulmonary edema, diastolic steal, and systemic hypoperfusion.
Hemodynamically Significant PDA (hsPDA) — Clinical and Echo Criteria
| hsPDA Concern | Clinical Criteria | Echo Criteria / Physiology |
|---|
| Pulmonary overcirculation | Increasing ventilator/CPAP need, pulmonary edema, inability to wean O₂/pressure, pulmonary hemorrhage risk | Large ductal diameter, unrestrictive L→R flow, LA/LV enlargement |
| Systemic steal | Wide pulse pressure, bounding pulses, hypotension, oliguria, feeding intolerance, poor growth, NEC history | Absent/reversed diastolic flow in descending aorta or systemic arteries |
| Myocardial load | Hyperdynamic precordium, tachycardia, cardiomegaly, worsening respiratory status | Volume-loaded LA/LV; possible LV dysfunction |
Management Options
| Management Option | When It Fits | Key Cautions |
|---|
| Expectant/conservative management |
Asymptomatic PDA, early PDA without major support needs, or small PDA |
Avoid excessive fluid; consider modest fluid strategy, optimize PEEP, treat pulmonary edema if present. Do not treat echo alone. |
| Ibuprofen |
Symptomatic hsPDA when treatment is indicated and contraindications absent |
Avoid in NEC, active bleeding, severe thrombocytopenia/coagulopathy, significant renal dysfunction, sepsis concern, or ductal-dependent CHD |
| Indomethacin |
Alternative when ibuprofen unavailable or local protocol favors it |
Greater renal/mesenteric concerns; withhold if oliguria/significant renal dysfunction. Avoid concurrent hydrocortisone due to perforation risk. |
| Acetaminophen |
Case-by-case when NSAIDs are contraindicated |
Evidence is evolving; avoid routine use unless local protocol supports it |
| Catheter closure |
Failed/contraindicated medical therapy or persistent symptomatic hsPDA; increasingly feasible in very small infants at experienced centers |
Requires cardiology/cath team review; assess anatomy/weight/respiratory status |
| Surgical ligation |
When catheter closure not possible and PDA remains clinically harmful |
Watch for post-ligation syndrome: hypotension, oxygenation failure, LV dysfunction, need for inotrope/lusitrope |
13. Clinical Decompensation in Known or Suspected CHD
Impending arrest warning signs
Rising lactate or base deficit · low/falling NIRS · poor pulses · worsening perfusion · oliguria · agitation/diaphoresis · worsening hypoxemia · tachycardia followed by bradycardia · apnea · increasing respiratory support requirement
| Likely Physiology | Immediate Actions | Avoid |
|---|
| Ductal-dependent systemic flow closing |
Start/increase PGE₁ per local policy; support ventilation; cautious volume if hypovolemic; vasoactive support; urgent echo/transfer |
Do not chase high saturation with O₂ if systemic perfusion is worsening |
| Ductal-dependent pulmonary flow closing |
Start/increase PGE₁; assess ventilation, acidosis, PVR triggers; cardiology for stent/shunt/valvuloplasty pathway |
Do not accept severe acidosis because saturation is "expected" |
| Inadequate mixing in TGA |
PGE₁, intubate if unstable, correct acidosis, immediate cardiology for balloon atrial septostomy |
Do not delay septostomy when restrictive atrial septum causes refractory hypoxemia |
| Pulmonary overcirculation / systemic steal |
Limit excessive O₂, optimize ventilation, consider diuresis if perfusion allows, support systemic output, urgent cardiology |
Avoid pulmonary vasodilation that steals systemic blood flow |
| Arrhythmia or myocardial dysfunction |
ECG, correct electrolytes/glucose/acidosis, targeted antiarrhythmic or cardioversion if unstable, echo for function |
Do not treat as sepsis alone if rhythm/perfusion pattern suggests cardiac cause |
14. Source Differences and How This Chapter Resolves Them
| Topic | Source Difference | Neonatology Academy Resolution |
|---|
| PGE drug and dose | Baylor uses PGE₁/alprostadil practice; West Midlands uses dinoprostone/PGE₂ with local dose bands; Belize describes PGE₁ and favors intubation for transport | Use local formulary and cardiac center dose. Clinical trigger and monitoring are emphasized; exact preparation must be verified locally. |
| CCHD screening thresholds | West Midlands and AAP/CDC algorithms are similar but not identical; AAP 2024/2025 updated US algorithm to require both pre- and postductal values to pass | For US-facing guideline, use AAP/CDC thresholds. Symptomatic infants bypass screening and need diagnostic evaluation. |
| Hyperoxia test | Belize describes hyperoxia testing as useful; modern high-resource pathways prioritize echo and PGE when symptomatic | Hyperoxia may help in resource-limited settings but should not delay PGE₁, echo, or transfer in an unstable infant. |
| PDA treatment timing | Older guidance often treated earlier; Baylor and recent AAP guidance favor expectant management for asymptomatic/early PDA and treatment for symptomatic hsPDA | Do not treat PDA solely because it is present. Use combined clinical and echo criteria. |
| Feeding on PGE | Practice varies widely due to NEC/mesenteric perfusion concern | Feed only stable infants under local cardiac feeding pathway; use human milk, slow advancement, and stop feeds during instability or PGE trial off. |
15. Common Mistakes
- Waiting for a murmur: a life-threatening lesion can present without a loud or diagnostic murmur.
- Treating saturation alone: SpO₂ of 80% may be acceptable in some pulmonary-flow lesions if perfusion and lactate are reassuring, while SpO₂ of 95% may hide pulmonary overcirculation and systemic steal.
- Delaying prostaglandin: a symptomatic neonate with possible ductal-dependent systemic or pulmonary flow should receive PGE₁ while the diagnosis is clarified.
- Assuming normal early 4-limb BP excludes coarctation: a large PDA may mask the gradient.
- Using oxygen indiscriminately: O₂ can lower PVR and worsen Qp:Qs balance in overcirculation/systemic-flow lesions.
- Ignoring lactate and urine output: shock is oxygen-delivery failure; BP may be a late or misleading marker.
- Feeding through instability: NEC risk rises when systemic and mesenteric perfusion are compromised.
16. Teaching Points
- Think physiology first: mixing, pulmonary flow, systemic flow, ventricular function, rhythm, and pulmonary vascular resistance.
- The ductus can be lifesaving or harmful depending on anatomy — do not close or open it without understanding the physiology.
- Cyanosis with minimal respiratory distress is cardiac disease or PPHN until proven otherwise.
- Shock in the first weeks of life is ductal-dependent systemic blood flow until proven otherwise, especially with weak femoral pulses or acidosis.
- Echo is the diagnostic anchor, but prostaglandin should not wait for echo when the infant is unstable and ductal dependence is plausible.
- Nutrition, temperature, pain control, respiratory work, anemia, calcium, glucose, and acidosis all affect O₂ delivery in CHD.
17. Key Takeaways — Chapter 3.3
- Screen well newborns, but diagnose sick newborns.
- Use right-hand and foot saturations, 4-limb BP, pulses, perfusion, lactate, UO, CXR/ECG, and echo together — not any single parameter in isolation.
- Start PGE₁ for symptomatic suspected ductal-dependent lesions or uncertain cyanosis/shock while arranging echo and transfer.
- Avoid reflex hyperoxia in lesions where pulmonary overcirculation may steal systemic output.
- Feed cautiously — systemic perfusion and mesenteric flow determine safety more than the label "PGE infusion."
- PDA treatment in preterm infants should be based on symptomatic hemodynamic significance, not PDA presence alone.
- Early communication with cardiology/cardiac ICU/transport is part of stabilization — not an optional later step.
18. References
- Fernandes CJ, Pammi M, editors. Guidelines for Acute Care of the Neonate. Edition 33, 2025–2026. Baylor College of Medicine / Texas Children's Hospital. Section 3, Chapter 3.3.
- Bedside Clinical Guidelines Partnership and West Midlands Perinatal Network. Neonatal Guidelines 2025–2028. Sections: Prostaglandin Infusion; CCHD Screening; PPHN; PDA.
- Constanza E. Neonatal Clinical Practice Guidelines 2018–2021. Ministry of Health Belize. Sections: Suspected neonatal CHD; patent ductus arteriosus.
- Oster ME, Pinto NM, Pramanik AK, et al. Newborn Screening for Critical Congenital Heart Disease: A New Algorithm and Other Updated Recommendations. Pediatrics. 2025;155(1):e2024069667.
- Centers for Disease Control and Prevention. Screening for Critical Congenital Heart Defects. Updated December 2025.
- American Heart Association and American Academy of Pediatrics. 2025 Guidelines for CPR and Emergency Cardiovascular Care, Part 5: Neonatal Resuscitation.
- Ambalavanan N, Aucott SW, Salavitabar A, Levy VY; AAP Committee on Fetus and Newborn; Section on Cardiology and Cardiac Surgery. Patent Ductus Arteriosus in Preterm Infants. Pediatrics. 2025;155(5):e2025071425.
- Hamrick SEG, Hansmann G, et al. Patent ductus arteriosus in preterm infants. Pediatrics. 2020;146(5):e20201209.
- Jasani B, Mitra S, Shah PS. Paracetamol (acetaminophen) for patent ductus arteriosus in preterm or low birth weight infants. Cochrane Database Syst Rev. 2022.
- Textbook of Neonatal Resuscitation. 8th edition. AAP/AHA.