Marc Anders. Hypoplastic left heart, Don't Forget the Bubbles, 2013. Available at:
Definition: abnormal left heart development resulting in underdevelopment of LV, aortic valve, aorta, mitral valve and aortic arch. Incidence 0.2:1000 of all live births.
PDA dependent systemic perfusion: PDA closure results in acidosis, hypoxaemia and shock.
In patients with restrictive ASD/PFO, cardiogenic shock develops right after birth.
Prominent loud single second heart sound
Coarctation, critical AS, IAA (all PDA dependant systemic lesions)
- Secure vascular access (two peripheral IVs or UVC)
- Commence prostaglandin E1 (20 ng/kg/min) to maintain systemic perfusion. Watch for apnoeas
- If deteriorating with pulmonary over-circulation (increasing saturations, decreasing perfusion): intubate and sedate to lower oxygen consumption with hypoventilation to increase PVR (aim for a pH 7.30-7.35) and to lower SVR (hypercarbia). SNP (0.5-4 mcg/kg/min to lower SVR – aim MAP >35 mmHg in neonates)
- With restrictive ASD/PFO: immediate intubation and resuscitation, urgent BAS or septectomy (10% of HLHS)
- No enteral feeds until surgical correction, consider gastric protection
Management of low CO preoperative:
- SpO2 >85 – excessive pulmonary blood flow: intubation, sedation, filling, SNP
- Impaired systemic ventricular function (+/- tricuspid regurgitation): consider intubation, dobutamine, milrinone
- SpO2 <65% and acidosis: confirm diagnosis of restrictive ASD via ECHO;intubation, resuscitation, urgent BAS
- Restrictive PDA (variable SpO2) → increase prostin
ECG, CXR, CUS, renal US, FISH, FBE, clotting,UECs, PRBC (4), FFP (2), platelets (2), cryoprecipitate (2)
Methylprednisolone 10mg/kg 12 hrs and 6 hrs pre surgery in neonates
Primary cardiac transplantation – not done in Australia (consider also compassionate care).
Norwood procedure: reconstruction of aortic root and aortic arch, disconnection of pulmonary trunk and incorporating the RV stump into systemic circulation; lung perfusion by BT Shunt (diastolic runoff) or Sano-Shunt (obstruction).
- Keep intubated, ventilated, sedated and paralysed for 24-48 hrs
- Inotropes: milrinone plus dopamine or adrenaline plus noradrenaline, aim MAP >40 mmHg in neonates, aim for maximal vasodilation to reduce strain on RV
- Haemodynamics: SBP > 60 mmHg, MAP >40 mmHg (increasing over time), CVP 8-12 mmHg
- Respiratory: balance circulation (SpO2 70 – 85%), normocapnea
- Fluid restriction: 1ml/kg/hr
- Introduce feeds when haemodynamically stable (not before day 2)
- Introduce captopril gradually when tolerating feeds and haemodynamically stable
- Commence aspirin 5 mg/kg OD once enteral full feeds established
- Consider clopidogrel 0.2 mg/kg OD (all surgical lines and pacing lines must be removed prior)
- Consider long term central venous access for feed intolerance and need for long term parenteral nutrition
- Low CO: keep paralysed, don’t wean inotropes <24 hrs → adaption of the RV for systemic circulation
- Anatomical coronary artery problems (check ECG, troponin). Early investigations (echo, cathlab)
- Coronary artery spasm (start GTN 5-10 mcg/kg/min)
- Arrhythmia and pacing
- Low urine output: start PD
- ECHO assessment: function of systemic RV, patency of BT shunt/Vmax across Sano shunt, degree of tricuspid regurgitation, adequacy of ASD, evaluation of neoaorta and arch
- Feed intolerance: consider feeding protocol
Mean ICU stay: 5 days
Mortality 30 days: up to 40%
HLHS w/ restrictive ASD and BAS: mortality up to 50%
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