1. www.latrobe.edu.au/nursing Patent Ductus Arteriosus Melissah Burnett La Trobe University, Melbourne. and Dr Kai König Mercy Hospital for Women Melbourne, Victoria, Australia

2. www.latrobe.edu.au/nursing Objectives Define Patent Ductus Arteriosus (PDA) Discuss the pathophysiology associated with PDA Identify risk factors for PDA Discuss the physiologic effects of a PDA on different systems. Demonstrate appropriate nursing care of a neonate with a PDA Describe the initial and long term management of a neonate with a PDA

3. www.latrobe.edu.au/nursing Definition Patent ductus arteriosus is the persistence in postnatal life of the normal fetal vascular conduit that connects the central pulmonary and systemic arterial systems. (Casteneda, Jonas, Mayer & Hanley, 1994)

4. www.latrobe.edu.au/nursing Fetal Ductus Arteriosus During fetal life DA is a normal structure Wide muscular connection between the pulmonary artery and the aorta Allows right to left shunting of blood away from the pulmonary bed

5. www.latrobe.edu.au/nursing Role of Ductus Arteriosus in the Fetus The DA allows blood to be diverted away from the high resistance pulmonary circulation into the Descending Aorta, towards the low resistance placental circulation Pulmonary Vascular Resistance Greater than Systemic Vascular Resistance results in a R → L shunt at the DA

6. www.latrobe.edu.au/nursing Fetal Ductus Arteriosus DA remains patent in-utero due to: Low Oxygen Tension Prostaglandins cases reported of antenatal DA closure resulting in (severe) right heart failure

7. www.latrobe.edu.au/nursing Ductal Closure Functional closure between 24-72 hours of age in term babies: 50% by 24 hrs, 90% by 48 hrs, all by 72 hrs (Doppler echo assessment) delayed or absent closure in preterm infants Balance between the constricting effects of O2, vasoconstrictive substances and relaxing effects of prostaglandins

8. www.latrobe.edu.au/nursing Structural Closure Takes place within 1-3 months Formation of ligamentum ateriosum Until structural closure, shunts may open and close intermittently

9. www.latrobe.edu.au/nursing Postnatal transition and DA closure Factors that promote ductal closure: increase in oxygen tension after birth decrease in blood pressure within the ductal lumen decrease in circulating PGE 2 due to loss of placental production and increase of its removal by the lungs decrease in number of PGE 2 receptors in the ductal wall in small preterms, decreased intrinsic ductal tone + increased sensitivity to vasodilating effects of PGE 2 and NO

10. www.latrobe.edu.au/nursing

12. Ductus arteriosus (DA) in the fetus

13. www.latrobe.edu.au/nursing Incidence 4th most common cardiac lesion In term babies 1:2000 live-births In pre-term babies 8:1000 live births Occurs 2-3 times more commonly in females than males Lower incidence in babies whose mothers had ante-natal steroids (24hrs)

14. www.latrobe.edu.au/nursing Incidence http://www.sswahs.nsw.gov.au/rpa/neonatal/

15. www.latrobe.edu.au/nursing Factors That Increase Incidence of PDA Respiratory distress syndrome Perinatal asphyxia High altitude at birth Congenital syndromes Congenital cardiac abnormalities Prematurity Sepsis Hypoxemia Excess IV fluids

16. www.latrobe.edu.au/nursing Factors That Decrease Incidence of PDA Maternal steroids Fluid restriction Increased gestational age Intrauterine growth restriction Prolonged rupture of membranes

17. www.latrobe.edu.au/nursing Clinical Manifestations Manifests at 3-7 days of life Tachycardia Tachypnoea Oxygen desaturation Systolic murmur Hyperactive precordium Bounding pulses/Widened pulse pressures Generalised oedema Deterioration of respiratory status Congestive Cardiac Failure

18. www.latrobe.edu.au/nursing Clinical Presentations Important to consider presentation of PDA in the neonatal period In the preterm infant In the term infant In the infant with cardiac abnormalities

19. www.latrobe.edu.au/nursing PDA in the Preterm Infant Prematurity and RDS are the two main causative factors for PDA The lower the GA the greater the risk of PDA Failure of the duct to close in preterm infants is not an abnormality of the DA

20. www.latrobe.edu.au/nursing PDA in the Preterm Infant Immature ductal tissue much less reactive to oxygen The DA remains sensitive to dilating effects of prostaglandins Likely to develop RDS

21. www.latrobe.edu.au/nursing PDA in the Preterm Infant In the preterm infant blood shunts Left → Right through the duct

22. www.latrobe.edu.au/nursing PDA in the Preterm Infant In the preterm infant blood shunts Left → Right through the duct Occurs when pulmonary vascular resistance decreases Results in pulmonary over circulation Increases the work of the left heart due to increased flow returning to left side

23. www.latrobe.edu.au/nursing Clinical Presentation in the Preterm Infant Systolic murmur Widening pulse pressure Bounding pulses Over active precordium Tachycardia Hypotension Worsening RDS Cardiac Failure

24. www.latrobe.edu.au/nursing PDA in the Term Infant May present as an isolated cardiac abnormality Mostly seen in relation to PPHN –Increased pulmonary vascular resistance (PVR higher than SVR)

25. www.latrobe.edu.au/nursing PDA in the Term Infant In the term infant with pulmonary hypertension blood shunts Right → Left through the duct

26. www.latrobe.edu.au/nursing PDA in the Term Infant PPHN can be caused by anything that causes Hypoxia Hypercarbia Acidosis Hypothermia

27. www.latrobe.edu.au/nursing PDA in the Cardiac Infant Forced ductal patency in duct dependant cardiac lesions Duct remains open to provide pulmonary or systemic flow Prostaglandin E1 infusion to ensure ductal patency

28. www.latrobe.edu.au/nursing PDA in the Cardiac Infant May present as an isolated cardiac abnormality accounts for 5-10 % of all CHD ’ s Allows left to right shunting re-entering the pulmonary circuit Mostly seen in relation to PPHN –Increased pulmonary vascular resistance (PVR higher than SVR)

29. www.latrobe.edu.au/nursing Diagnosis of PDA Clinical examination Heart sounds Cardiac echo EKG Chest X-ray

30. www.latrobe.edu.au/nursing Clinical Signs systolic murmur, bounding pulses, hyperactive precordium, increased O2/ventilation requirement late clinical signs = signs of heart failure Echo + Doppler: PDA diameter and shunt, AO:LA ratio increased, volume loading of left heart, decreased/absent diastolic flow in superior mesenteric artery, middle cerebral artery or renal artery

31. www.latrobe.edu.au/nursing Heart Sounds The pulse volume may be increased, the precordium is often active and there is a continuous murmur in the left infraclavicular region. http://www.medindia.n et/patients/PatientInfo /audios/pda.mp3http://www.medindia.n et/patients/PatientInfo /audios/pda.mp3

32. www.latrobe.edu.au/nursing Cardiac Echo This easily allows the ductus to be seen and the size measured. An estimate of the shunt size can be made from the Doppler pattern and the size of the left atrium and left ventricle.

33. www.latrobe.edu.au/nursing Turbulance

34. www.latrobe.edu.au/nursing Shunt Direction

35. www.latrobe.edu.au/nursing Haemodynamic Significance

36. www.latrobe.edu.au/nursing EKG If there is a significant shunt then there will be left ventricular hypertrophy evident.

37. www.latrobe.edu.au/nursing Chest X-ray If there is a significant left to right shunt then the heart will be enlarged and pulmonary plethora present.

38. www.latrobe.edu.au/nursing Management of PDA Oxygenation Fluids Weight Assessment Parents

39. www.latrobe.edu.au/nursing Management of a PDA in the preterm infant Two opinions re management of a PDA a PDA ? Just close it. God gave us a PDA, so why should we close it?

40. www.latrobe.edu.au/nursing PDA in the preterm infant ongoing controversy – should a PDA be treated? no convincing data despite numerous studies of prophylactic or therapeutic indomethacin/ibuprofen no decrease in death, chronic lung disease, neurodevelopmental outcome Who should be treated?

41. www.latrobe.edu.au/nursing PDA in the preterm infant Individual approach required – disease staging: What is the infant’s gestational age?  the lower gestation, the higher the risk for PDA How old is the infant?  increasing age decreases likelihood of treatment success  requires early diagnosis -> requires early echo (clinical signs of PDA are late signs) Is the PDA haemodynamically significant?  clinically significant/ echocardiographically significant

42. www.latrobe.edu.au/nursing PDA in the preterm infant Clinical disease staging: oxygenation? ventilator dependent? apnoea/bradycardia/desaturations? feeding intolerance? hypotension? metabolic acidosis? renal function?

43. www.latrobe.edu.au/nursing Management of a PDA in the preterm infant watch and wait for spontaneous closure fluid restriction keep haematocrit normal ventilation/PEEP indomethacin/ibuprofen (prostanglandin inhibitor) surgical ligation

44. www.latrobe.edu.au/nursing Management of a PDA in the preterm infant Indomethacin/ibuprofen: constricts the DA risk of treatment failure and ductus reopening highest in smallest babies and late initiation of treatment efficacy of 2 nd course rather low ibuprofen less effect on renal perfusion (lower incidence of renal impairment) and mesenteric blood flow

45. www.latrobe.edu.au/nursing Management of a PDA in the preterm infant Indomethacin/ibuprofen adverse effects: renal failure/oliguria (indo > ibu) Indo in conjunction with steroids may increase risk of GI perforation ? less NEC with ibu ? less BPD with indo

46. www.latrobe.edu.au/nursing Management of a PDA in the preterm infant Surgical ligation: (relatively) safe procedure in experienced hands growing concern re effects of surgery and/or anaesthesia on the developing brain cardiac function impaired post ligation for 24-48 hrs surgery-associated complications (pneumo-/chylothorax etc)

47. www.latrobe.edu.au/nursing Management of a PDA in the preterm infant Interaction between PDA and neonatal drugs: surfactant - higher incidence of PDA since its introduction caffeine - less PDA in CAP trial, but no direct effect in animal model inotropes - not reported frusemide - stimulates synthesis of renal PGE 2 -> can promote PDA

48. www.latrobe.edu.au/nursing Indomethacin Prostaglandin inhibitor Constricts the DA and vasodilates other vascular beds Dosages and regimes

49. www.latrobe.edu.au/nursing Surgical Closure

50. www.latrobe.edu.au/nursing Outcomes and Complications Dependant on pre-existing conditions and severity of symptoms prior to closure May be more at risk of –Infective Endocarditis –NEC –Intracranial haemorrhage –ROP –Chronic lung disease

51. www.latrobe.edu.au/nursing Management of a PDA in the term infant PDA in PPHN – treat underlying cause, manage PPHN  PDA will resolve once normal postnatal circulation is established PDA as an isolated anomaly – watch and wait  close interventionally (coil, occluder) or surgically later in life

52. www.latrobe.edu.au/nursing Key Points (from RPA) Risk of PDA increases with lower gestation, no antenatal steroids and hyaline membrane disease. Early diagnosis requires high degree of suspicion and echocardiography. The negative impact of ductal shunting on the systemic circulation is most marked in the early hours after birth. Indomethacin or Ibuprofen are the first line treatment with surgery if that fails or is contraindicated.

53. www.latrobe.edu.au/nursing Key Points (from RPA) There is no evidence that prophylactic indomethacin improves long term neuro developmental outcomes. (TIPP trial awaiting publication) Targeted early treatment of ducts, that fail to constrict spontaneously, is justified but not proven to improve outcomes. If the duct has closed 24 hours after the first dose, consideration should be given to not giving further doses.

54. www.latrobe.edu.au/nursing References Castaneda, A. R., Jonas, R. A., Mayer, J. E., & Hanley, F. L. (1994) Cardiac Surgery of the Neonate. W.B. Saunders Company: Philadelphia. DiMenna, L., Laabs, C., McCoskey, L., & Seals, A. (2005). Management of the Neonate with Patent Ductus Arteriosus. Journal of Perinatal and Neonatal Nursing, 20 (4). p 333 – 344. Deacon, J. & O ’ Neill, P. (1999) Core Curriculum for Neonatal Intensive Care Nursing (2 nd ed), W.B. Saunders Company, Sydney Kenner, C., Lott, J.W. & Flandermeyer, A.A. (1998) Comprehensive Neonatal Nursing – A Physiologic Perspective (2 nd ed.), W.B. Saunders Company, Sydney Bland A (2008) Patent Ductus Ateriosus, Lecture Merenstein, G.B. & Gardner, S.L. (2002) Handbook of Neonatal Intensive Care Nursing (5 th ed), Mosby, Sydney Medhurst, A. (2006) The Premature Baby With Patent Ductus Arteriosus, Lecture Persaud, T.V.N. & Moore, K.L. (2003) The Developing Human – Clinically Orientated Embryology, Saunders, Philadelphia.

55. www.latrobe.edu.au/nursing References Castaneda, A. R., Jonas, R. A., Mayer, J. E., & Hanley, F. L. (1994) Cardiac Surgery of the Neonate. W.B. Saunders Company: Philadelphia. DiMenna, L., Laabs, C., McCoskey, L., & Seals, A. (2005). Management of the Neonate with Patent Ductus Arteriosus. Journal of Perinatal and Neonatal Nursing, 20 (4). p 333 – 344. Kenner, C., Lott, J. W. (2007). Comprehensive Neonatal Care (4 th ed), Saunders Elsevier: Missouri. Rennie, J, M. (ed) (2005). Roberton’s Textbook of Neonatology. Elservier Limited: United Kingdom. Schneider, D. J., & Moore, J. W. (2006) Patent Ductus Arteriosus. Circulation.114, p 1873 – 1882.

56. www.latrobe.edu.au/nursing References Polin, R.A. & Spitzer, A.R. (2001) Fetal and Neonatal Secrets, Hanley & Belfus Inc, Philadelphia.. Rennie, J, M. (ed) (2005). Roberton ’ s Textbook of Neonatology. Elservier Limited: United Kingdom. Schneider, D. J., & Moore, J. W. (2006) Patent Ductus Arteriosus. Circulation.114, p 1873 – 1882. Patent Ductus Arteriosus, Heart Point, Retrieved July 2006, from http://www.heartpoint.com/congpda.html http://www.heartpoint.com/congpda.html Patent ductus Arteriosus, Pediheart.org, Retrieved July 2006, from http://www.pediheart.org/parents/defects/PDA.htm http://www.pediheart.org/parents/defects/PDA.htm Sethuraman, G. (2006) ‘ Patent Ductus Arteriosus ’ EMedicine, Retrieved July 2006, from http://www.emedicine.com/emerg/topic358.htm http://www.emedicine.com/emerg/topic358.htm Sturrock-Fox C 2008 Patent Ductus Ateriosus. Lecture Patent Ductus Arteriosus, Royal Children ’ s Hospital Cardiology Department, Retrieved July 2006, from http://www.rch.org.au/cardiology/defects.cfm?doc_id=5073http://www.rch.org.au/cardiology/defects.cfm?doc_id=5073