Pulse Oximetry Screening for Critical Congenital Heart Disease (CCHD): Early WA Experience. Jim Ramsay Children s Cardiac Centre Perth

Transcription

1 Pulse Oximetry Screening for Critical Congenital Heart Disease (CCHD): Early WA Experience Jim Ramsay Children s Cardiac Centre Perth

2 Overview of Presentation WA Oximetry Screening Origins Critical CHD - Intro to problem Oximetry screening for CCHD WA Oximetry study to date Logistical problems Screening results CCHD in WA Early results from review Possible Future directions

3 WA Oximetry Screening - Origins In late 2010 KEMH neonatologists contacted Cardiology at PMH re feasibility of introducing oximetry screening based on AHA 2009 (and other) papers Another neonatologist introduced oximetry screening to two smaller maternity units in South Perth in early 2011 following a missed diagnosis in 2010 KEMH started informal oximetry screening in late 2011

4 HeartKids Grant Recognising that oximetry obviously does detect cases of CCHD Concerned re increase in echocardiography requests without increase in resources New HeartKids Australia grants of up to $50,000 available and applied for in Sept 2011 Contacted a number of maternity units to see if they would particpate in a pilot study KEMH, St John s Subiaco, Glengarry, Joondalup, Attadale and Kalleya?Total no of births approx 14,000 per year Received notice of successful grant application in late December Funding of $45,000 for 0.4 FTE echocardiographer

5 WA Oximetry Study - Background Increasing literature over last decade on the use of oximetry screening in newborns to detect critical congenital heart disease (CCHD) American Heart Association released consensus statement in 2009 re Screening More evidence in last 2-3 years with big studies from Europe - Sweden, Germany, Norway and UK Oct 2011 article in Paediatrics (Kemper et al ) representing committee from US Health and Human Services recommended a protocol for oximetry screening January Endorsement by American Academy of Pediatrics and American Heart Association of Recommendation for Pulse Oximetry Screening for CCHD

6 US CHD Screening Map

7 Critical Congenital Heart Disease Congenital Heart Disease (CHD) most common congenital disorder CHD 1% newborns, of which ~15-25% (1-3/1000) have CCHD Diagnosis of CCHD: Antenatal ~ 20-60% Postnatal (prior to discharge)~20% with murmur, resp distress, shock or cyanosis ~20%-25% may not be diagnosed before discharge Earlier discharge may exacerbate this problem

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10 Left Heart Obstructive Lesions H y p o p l a s t i c L e f t Conditions where obstruction to the systemic blood flow causes heart failure and often shock Depends on severity of obstruction and timing of closing of PDA - ductal dependent Hypoplastic left heart syndrome Coarctation of aorta Critical aortic stenosis Interrupted aortic arch H e a r t S y n d r o m e

11 RVOTO Physiology Problem is obstruction to pulmonary blood flow Number of cardiac problems beginning at tricuspid valve and going through to pulmonary valve Many lesions ductal dependent Tricuspid atresia Ebstein s anomaly Critical pulmonary stenosis Pulmonary atresia + IVS Tetralogy of Fallot Pulmonary atresia + VSD

12 Transposition Physiology Problem is systemic pulmonary circulations in parallel with poor mixing Can be seen in different forms of TGA TGA + IVS TGA + VSD Complex TGA Need mixing at atrial, ventricular or great artery level

13 Antenatal Diagnosis Antenatal diagnosis varies 25-80% major CHD depending on the lesion, sonographer experience, fetal position and maternal weight Traditionally 4 chamber views only, now look at outflow tracts too TGA/Coarct less likely to be diagnosed

14 Postnatal Diagnosis of CCHD Murmurs Femoral pulses weak Fast breathing Cyanosis (blueness) Shock

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16 Postnatal Diagnosis Murmurs between 0.6% and 4.2% neonates Many benign or minor CHD Transitional circulation Benign peripheral pulmonary stenosis Small VSDs Conversely many Critical CHD NO murmur in first few days inc TGA, HLHS, CoA, TAPVR

17 Postnatal Diagnosis Cyanosis (clinical determined) 4 to 5 g of deoxygenated haemoglobin is needed to produce visible central cyanosis independent of haemoglobin concentration. For the typical newborn with a haemoglobin concentration of 17g/dL, cyanosis will only be visible when arterial oxygen saturation is 80% Harder in dark skinned babies

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19 Postnatal Diagnosis Femoral Pulses May be present day 1 then diminishing in coarctation of the aorta due to PDA Normal femorals on day 1 is not necessarily reassuring Need to be checked again on discharge Early discharge reduces chance of detection

20 Postnatal Diagnosis Shock Variable timing of presentation Cardiac shock usually from day 2-3 (may have gone home ) Coarctation may present up to 2 weeks of age (as ductal tissue in an around aorta narrowing continues to contract)

21 Why is it best to diagnose before discharge? Ductal dependent lesions present with circulatory collapse and potentially death if not treated 3-6% TGA die before diagnosis 1.7% all heart defects die before diagnosis Critical coarct (or interrupted arches) and HLHS most at risk UK 0.4-2/10000 delayed/missed CCHD Those resuscitated may have suffered significant acidosis and potential long term neurological and cardiac consequences Timely diagnosis can improve outcomes

22 Pulse oximetry to help detect CCHD Painless and non-invasive way to measure oxygen saturation of haemoglobin in arterial blood Aim to reduce number of babies discharged home with undetected CCHD Been studied for many years, but only large studies in Europe from 2007 Big studies from Sweden, Germany and UK

23 Systematic Meta- analysis Review >229,421 babies in observational studies using 95% cut off 13 studies Sensitivity (detect DISEASE) 76.5% Specificity (detect HEALTH) 99.9% False positive rate 0.14% Lancet :2459

24 Timing 2012 Lancet : False positive rate much lower after 24 hours (0 05% [ ] vs 0 50 [ ]; p=0 0017). Conclusions: babies should be screened on day 2 where possible, those with saturations 90-95% on day 1 could be observed until 24 hours and echo obtained after this if still </=95%

25 False positives Studies have found up to 50% will have other causes mainly infection Important to rule out infection/polycythaemia

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27 Cost AAP estimate $1/baby screened UK estimate cost 1500 in 2005 for one positive case Recent estimate 24,000 per positive case from PulseOX study

28 KEMH Guidelines for Oximetry Screen all neonates born at KEMH prior to discharge (ideally at >24 hours age, but for early discharge within 1 hour of discharge) with lower limb 0 2 saturations. The trace needs to be good (need a monitor with visible pulse trace) and take the highest number the trace gets to as the screening number. The baby should not be feeding and should be settled. This can be done by a midwife or ward RMO

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30 KEMH Audit First 6 months Dec 11-Jun babies screened 2 failed initial screen passed 3-4 hours late 1 failed 2 screen (4 hours apart) had normal echo Problems: initially missing babies (est 35%)- discharged without screen Reasons: lack education re protocol (hundreds of midwifes.), frequent RMO change overs, early d/c, Day 1 check done prior 24 hours so no oximetry done Improvements: documentation, education

31 WA Oximetry Study Significant logistical problems Funding for echocardiographer delayed for five months - didn t begin until end May 2012 Neonatologists from two of original units left and no agreement to take part in study has been reached Problems with who will do oximetry Midwives not happy at KEMH or other public hospitals to take on extra workload Residents doing at KEMH currently Original neonatologist who was driving study left KEMH

32 WA Oximetry Study Percentage screened has been very variable up to 40% not being screened at KEMH, but has improved recently towards 75% Didn t begin formal screening study until September 1st 2012 Working well at St John of God Hospital in Subiaco and at Attadale Hospitals Added Broome Hospital into study in Oct 2012 Midwives at SJOG Hospital have taken on the role of screening and have not missed any babies - now part of routine discharge check Driven by two neonatologists

33 WA Oximetry Study - Results Total babies screened since September 1st 2012 until end June/July 7051/8883 (81% screened) No true positives Only two false positives One had abnormal Hb One with Down syndrome - had echo PDA only - no CCHD One false negative - TAPVR normal echo sats at 6 days

34 Hospital No of births No screened % Screened KEMH % St John of God % Kaleeya % Attadale % Broome?240 93?39% Total %

35 WA Critical CHD Study Review of all babies from WA born with CCHD from 1/1/2011 to present date - plan to finish on 31/12/2013 To complement the oximetry study as not actually documented how significant the problem of babies being discharged without a diagnosis being made in WA

36 WA Critical CHD Study From 1/1/2011 to 31/8/2012 study was retrospective From 1/9/2013 the study was prospective when we started the Oximetry Screening Reviewed surgical and cardiac catheter databases, Cardiobase, Synapse (Echo database) and patient records

37 WA Critical CHD Study - Results 1 91 babies diagnosed with CCHD 45/91 (49%) antenatal diagnosis (fetal echo) 46/91 after birth - 28/91(31%) while in hospital due to clinical symptoms or abnormal exam 18/91 (20%) after discharge from hospital Number of babies presented with significant haemodynamic compromise Contacted Forensic Pathology in Perth - no babies detected with cardiac lesion that died suddenly and unexpectedly in same period

38 WA CCHD Study - Antenatal Diagnosis Total 45/91 HLH syndrome - 3 CoA - 4 Interrupted Aortic Arch - 1 PA + IVS - 6 PA + VSD - 1 Tetralogy - 7 Tricuspid atresia - 1 Tricuspid stenosis HRV - 1 Critical PS - 1 TGA - 7 (5 IVS + 2 VSD) Truncus - 1 Miscellaneous complex -12 Single ventricle DORV Unbalanced AVSD Situs inversus dextrocardia Right isomerism etc

39 WA CCHD Study - Postnatal Diagnosis Before Discharge - 28/91 TGA - 11 CoA - 5 Critical PS - 3 Critical AS - 1 Tetralogy - 4 PA + IVS - 1 Truncus - 1 AVSD with CoA - 2

40 WA CCHD Study - Postnatal Diagnosis CoA - 6 After Discharge - 18/91 TGA - 4 ( 3 with VSD) TAPVR - 3 ( 1 documented sats at 6 days of 95%) Tetralogy - 3 PA + VSD with MAPCAS - 1 Ebstein anomaly - 1

41 WA CCHD Study - Outcomes 91 babies diagnosed with CCHD 3 babies families elected for palliative care 1 baby died before surgery 84 babies had procedures 2 waiting for operation still 6 post-op deaths Mortality 11% (10/91) No deaths in babies discharged before diagnosis made

42 WA CCHD Study - Summary WA study similar to other reviews of CCHD around world Approx 50% diagnosed by fetal echo Approx 20% discharged from hospital with unsuspected CCHD Of those discharged probably more than 50% could have been detected with pulse oximetry screening

43 Conclusions Lancet Editorial in June 2012 entitled A New Milestone in Congenital Heart Disease commenting on meta-analysis paper concluded that the question shouldn t be Why should pulse oximetry screening be introduced but Why should such screening not be introduced more widely?

44 Conclusions Important to realise that Oximetry Screening is not a panacea Some babies will still not be diagnosed particularly with Coarctation type problems Some significant logistical problems to be overcome

45 Future Directions Believe we should plan to introduce oximetry screening to other maternity units in WA Aim to introduce statewide Develop protocols for introduction that makes part of routine discharge planning Try to encourage midwives to be more involved in performing oximetry Education of paediatricians, nursing staff and families

46 Future Directions PMH Grand Round next week on Oximetry run by KEMH where I will present results of studies More talks scheduled in October 2013 with KEMH and Neonatal Network Abstracts for CCHD study to PMH Research and Advances Symposium Abstracts to be sent to World Congress of Cardiology to be held in Melbourne May 2014 on Oximetry and CCHD Studies In World Congress there will be a session on Early Detection of CHD which I have been asked to chair

47 Oximetry References Brown KL, Ridout DA, Hoskote A. et al. Delayed diagnosis of congenital heart disease worsens preoperative condition and outcome of surgery in neonates. Heart 2006;92: Mahle AT, Newburger JW, Paul Matherne G et al. Role of pulse oximetry in examining newborns for congenital heart disease: a scientific statement from the AHA and AAP. Pediatrics 2009;124: Tautz J, Merkel C, Loersch F et al. Implication of pulse oxymetry screening for detection of congenital heart defects. Klin Padiatr 2010; 222(5):291-5 Riede FT, Worner C, Dahnert I et al. Effectiveness of neonatal pulse oximetry screening for detection of critical congenital heart disease in daily clinical routine- results from a prospective multicenter study. Eur J Pediatr 2010; 169: De Whal Granelli A, Wennergren M et al, Impact of pulse oximetry screening on the detection of duct. dependent congenital heart disease: a Swedish prospective screening study in newborns BMJ 2009;338:a3037 Walsh W. Evaluation of pulse oximetry screening in Middle Tennessee: cases for consideration before universal screening. J Perinat 2011; 31, Swiss National guideline: Pulse oximetry screening for congenital heart defects in Switzerland: most but not all maternity units screen their neonates. Swiss Med Wkly 2009 Nov 28;139(47-48): Pulse oximetry screening for critical congenital heart defects: a UK national survey Lancet 281 Thangaratinam S, Brown K, Zamora A et al. Pulse oximetry screening for critical congenital heart defects in asymptomatic newborn babies: a systematic review and meta-analysis. Lancet :2459 Meberg A, Andreassen, Brunvand L, Markestad T, Moster D, Nietsch L, Silberg IE and Skalevik JE. Pulse oximetry screening as a complementary strategy to detect critical congenital heart defects. Acta Paediatrica 2008 Garg LA et al., Results From the New Jersey Statewide Critical Congenital Heart Defects Screening Program Pediatrics 2013; 132:2 e314

48 Oximetry Resources