Duct dependent circulation.ppt2
- 1. Management of a Patient with duct dependent circulation Dr Anil S.R Consultant Pediatric Cardiologist Apollo Hyderabad
- 2. Duct dependent Physiology • Pulmonary Circulation • Systemic Circulation • Both Circulation- Intercirculatory Mixing
- 3. Duct dependent Pulmonary circulation • Pulmonary atresia- VSD or Intact Septum • Severe TOF • Neonatal Ebsteins • Critical PS- Isolated or with complex CHD • Severe Tricuspid Valve regurgitation
- 4. Duct dependent systemic circulation • Left heart: Hypoplastic left heart • Critical AS • CoA • Interrupted arch
- 5. Pulmonary Vs Systemic Pulmonary Cyanosis predominant- Hypoxia dominating the clinical picture Relatively well at least initially- present in 24-48 hours of life Systemic Poor Perfusion- Decreased cardiac output Sick infants- present in the first 2 weeks of life.
- 6. Suspect and Rule out • Any baby with shock or collapse after 24 hours- “Duct Dependent systemic circulation” – Poor perfusion, absent pulses, pallor, shock • Cyanosis • Differential cyanosis • Respiratory symptoms but lungs clear • No response to oxygen or worsening with oxygen
- 9. Prenatal Physiology • Severe left or right sided lesions do not affect fetal growth and development. • Factors that mimic fetal circulation will stabilize the neonate. • Ductus-dependent fetal cardiac defects are contraindications to the maternal use of prostaglandin inhibitors during pregnancy.
- 10. Neonatal Cardiac Evaluation •General Evaluation Airway,Breathing,Circulation History and Examination •Inspection and Palpation Activity Cyanosis Peripheral Perfusion Dysmorphism and System Review
- 11. Neonatal Cardiac Evaluation •Auscultation Single S2 Murmurs +/-
- 12. Neonatal Cardiac Evaluation •Saturations •4limb BP •Liver Size •Auscultation •CXR •Hyperoxia Test •ABG- pH, PCO2, pO2, HCO3,Blood Sugar •Septic Workup
- 13. Hyperoxia Test 100% Oxygen (or as close as possible) for 10 minutes -by Blow by Mask, intubation -Repeat pO2 assessments by ABG -Pulseoximeter is Unacceptable Measure right arm pO2 pO2 > 250 – Unlikely to be Cyanotic CHD pO2 100-250 – possible cyanotic CHD pO2 <100 – Cyanotic CHD
- 15. Diagnosis of duct dependence Echo is the gold standard -Delineate the anatomy -Assess the size of PDA, degree of restriction/constriction -Assess PVR/SVR ratio on the flow pattern across the duct
- 16. Management Principles Back to Basics A , B, C and Drugs (Prostaglandin E1)
- 17. Management of Sick Neonate • Ensure Airways • Optimise Oxygen • Breathing - Good Now - Will it Sustain? - Fatigue an issue - When to ventilate? • Ventilate : Off load work of breathing Ensure good Oxygenation Secure Lines Secure airways Concomitant respiratory issues
- 18. When in doubt • Blue baby • Baby in shock Start………………Prostaglandin
- 19. PGE1 Preparation • Available as PROSTIN VR from Upjohn pharmacia as 1 ml ampoules containing 500 mcg/ml. • We dilute 0.1 ml (50 mcg) in 50 cc 5% Dextrose under laminar air flow to avoid sepsis. • The remaining PGE1 is stored in a fridge at 2-8o C. • Dilute 0.1 ml (50 mcg) in 50 ml 5%D; in this dilution, each ml equals 1 mcg of PGE1
- 20. PGE1 infusion protocol • PGE1 infusion is started at 0.05 - 0.1 mcg/kg/min • Depending on clinical response ( Saturations, femoral Pulse, urine output) infusion rates can be increased upto 0.4 mcg/kg/min • Once a desired response is obtained, (stable sats of 70 - 80% ) maintain patency by continuing infusions at 0.01 - 0.05 mcg/kg/min • It is often possible to bring down the rate to low levels to maintain effect
- 21. 0.01 mcg/kg 0.025 mcg/kg 0.05 mcg/kg 0.1 mcg/kg 2 kg 17 days 7 days 3.5 days 2 days 3 kg 12 days 5 days 3 days 1.5 days 4 kg 8 days 3.5 days 2 days 1 day How long does one Ampoule last?
- 22. Monitoring PGE1 Hypotension : Manifests as cold extremities, delayed capillary refill > 3 min tachycardia, low urine Rx : IV fluid bolus 5-10 ml/kg N.Saline in Apnea : Often noted in first hours, noted by apnea monitor or a watchful nurse (ideal). common in < 2 kg, preterms Rx : Stimulation, Hand Bagging, Ventilation
- 23. Fever : often in first 24 hours, needs tepid sponging Rx : Ensure that insensible fluid losses of a febrile neonate are met adequately Fluid retention: Often a common problem Seizures: Rare, may need cessation of PGE1 infusion Rx : Rule out other metabolic and infective causes in a sick neonate Monitoring PGE1
- 24. Monitoring PGE1 Bradycardia : if severe stop infusion Flushing : often noted in first few hours Others : Diarrhea, sepsis, DIC, Low K+. > 7 DAYS USE : Long bone hyperosteosis Gastric outlet (antral)obstruction
- 25. PDA patency • Oral/IV PGE • Atropine • PDA balloon/Stent
- 26. Surgical alternative: BT shunt • Shunt blockage:Acute thrombosis • Shunt overflow: CHF, pleural effusions • Chylothorax • Diaphragmatic paralysis • Late: Pulmonary artery distortion or stenosis
- 27. Keeping the PDA patent • Formalin infiltration of PDA at thoracotomy-invasive • Early experience of PDA stenting – Perforation of PA’s/chambers – PDA’s longer, tortuous, vertical in cyanotic CHD-axillary cut down needed – Inability to enter the duct, ductal spasm, incomplete stenting
- 28. PDA stenting • Current coronary equipment:better flexibility, lower profile • Heparin coating and drug elution may prolong palliation • 4F long Cook sheaths; cut pig (u) for vertical ducts or Judkins right • Extra support choice PT wire
- 29. PDA stenting • Transfemoral or transvenous via the VSD • Need to cover complete length of PDA esp distal end near PA • Measure length once PDA fully straightened by extra stiff wire
- 30. Blue babies: Other Non surgical Rx • Critical PS/AS/TOF with valvar stenosis Emergent non-surgical Rx: – Valvuloplasty • Atresia: – Valve perforation with straight wire or 2F RF ablation
- 31. D-TGA: Non surgical Rx Key is to ensure mixing Fluid boluses PGE1
- 32. Life saving in TGA where inadequate mixing can lead to cyanosis and low cardiac output Use umbilical or femoral vein Balloon atrial septostomy
- 33. • Keep calm • Knee chest • IV fluid bolus • Bicarbonate • Morphine IM or SC • Metoprolol (0.1 mg/kg) • Phenylephrine • If all else fails: • General anesthesia • or Spells
- 34. Conclusion • The key to a successful outcome in duct dependent cardiac lesions is… to realise the baby IS duct dependent!! Thank you!