Working Towards Neonatal Pulse Oximetry Screening to Detect Critical CHD Dalhousie Fall Refresher Course 2015 Kenny K Wong, MD, FRCPC Pediatric Cardiologist Associate Professor of Pediatrics
Objectives 1. Explain how neonatal pulse oximetry screening can help detect critical congenital heart disease. 2. List lesions that can be missed with screening and how to detect them. 3. Recognize the steps needed to work towards implementing neonatal pulse oximetry screening in your centre.
The Recommendation All newborns get pulse oximetry testing before discharge to enhance detection of critical congenital heart disease. DOES NOT rule out ALL CHD NOT a substitute for clinical exam
Refresher on Cardiac Cyanosis BLUE blood into the aorta causes cyanosis L R keeps you PINK R L makes you BLUE (Stanford Children s Health, 2015a) (Standford Children s Health, 2015c)
What is Ductal Dependency? A patent ductus arteriosus forms an essential bypass pathway to secure systemic or pulmonary blood flow Prostaglandin can keep the ductus open Discovered by Dr. Peter Olley at SickKids in 1973 (Stanford Children s Health, 2015b)
Critical Congenital Heart Diseases Require surgery in the the first weeks of life Typically cause cyanosis Not all duct dependent Coarctation of the aorta Transposition of the great arteries Hypoplastic left heart syndrome Tetralogy of Fallot Truncus arteriosus Ebstein anomaly Interrupted aortic arch Pulmonary atresia Tricuspid atresia Double outlet right ventricle Single ventricles Total anomalous pulmonary veins
Why Does This Matter? Congenital heart disease is common ~8/1000 born with CHD, ~1/1000 critical CHD Compared to PKU 1/15000, MCAD 1/18500 CHD is a leading cause of infant deaths ~30% discharged without a diagnosis Earlier detection decreases morbidity and mortality (Thangaratinam et al., 2012) (Wren et al., 2008) (Prudhoe et al., 2013)
Isn t What we are Doing Enough? Antenatal ultrasound detection is very good Wide regional variations Physical exam is helpful Adding pulse oximetry screening to lower the diagnostic gap Figure 2: (Riede et al., 2010) (Gardiner et al., 2014) (Riede et al., 2010) (Prudhoe et al., 2013)
In the Maritimes 115 cardiac surgeries for critical CHD (08-13) Overall 49% (56) diagnosed after birth Detection rates: 69% NS, 67% PEI, 33% NB 41/56 (73%) diagnosed prior to discharge 27% were discharged as normal Pulse oximetry will help us do better (Hammer & Wong, 2014)
Why Focus on Pulse Oximetry? It is easy, non-invasive, and readily available Cyanosis is common in critical CHD lesions Difficult to clinically detect cyanosis Cyanosis may be the earliest (only) sign Can also detect important respiratory disease
The Road to Screening Validity Subject of publications since 1990s 2009 AHA and AAP said there was a role but not ready for universal screening 2010 US DHHS recommended CCHD added to screening, with implementation concerns 2012 studies with another 100000 patient enrollment brought it into primetime (Ewer et al., 2011) (Mahle et al., 2012)
Assessing Pulse Oximetry as a Tool Normal sat = 98.5% chance no critical CHD Low false positive rate 0.5% (.29-.86%) Testing after 24H, 0.05% (0.02-0.12%) Equates to 2-12/10000 live births False positives mostly due to the transitional fetal circulation (Thangaratinam et al., 2012)
The False Negatives - 0.01% Coarctation remains a challenge Most likely to be missed Difficult antenatal diagnosis May not be desaturated No baby should be discharged without normal femoral pulses PRACTICE PEARL: Compare brachial pulses to femoral pulses (Stanford Children s Health, 2015d) (Hammer et al., 2014) (Gardiner et al., 2014)
American Academy of Pediatrics Algorithm Abnormal <90% Normal 95% AND 3% difference Borderline 90-94% OR >3% difference (Kemper et al., 2011)
What Have we Learned so far? Not expensive or time consuming Thorough clinical evaluation by physician rather than immediate transfer for an echo May not be as helpful in tertiary care settings with excellent antenatal detection More helpful in smaller centres False negatives are rare Applied successfully to home births, NICUs
We do Selective Testing Already Any baby with cardiac findings gets a sat Pulse Ox screening removes the subjective assessment for cyanosis Any blue baby would have been considered for an echo anyways
IWK HEALTH CENTER EXPERIENCE
Steps Towards Implementation Decide on who is going to be involved Who gets called and what to do with abnormals Clinical evaluation by MD rather than automatic echo What about the weekends or weeknights Logistics What time of day to screen Discuss practicalities of doing the screen
Steps Towards Implementation Engage the nurses by focusing on improving patient care Education will help overcome initial pushback Concern for missed critical CHD will motivate Emphasize that it s just another vital sign Respect that all nurses are familiar and capable of doing pulse oximetry testing
Steps Towards Implementation Documentation is important Best to be part of the nursing care path Get necessary program approvals Go up the administrative chain as there may be competing funding demands Teaching using existing infrastructure
IWK Pulse Ox Experience Since 03/13 Highly collaborative team made it easy 3 pulse ox machines adequate for our unit with over 4000 neonatal admissions Reusable probes $250 each, last ~1 year, washable probe wraps ($37 for 12) Checks usually done during bath time Estimate 10 minutes to test, clean equipment and document
IWK Pulse Ox Experience Since 03/13 5 abnormal screens, no false negatives 3 false positive, 2 true positives (Tetralogy of Fallot and Ebstein) Some regional centres are screening too Abnormals get referred to pediatrics Transfer for outpatient echo or NICU admission Benefit from live transmission of echo images Abnormal weekend screens are kept till weekday
What s Next A position statement is coming NS Reproductive Care Program is supportive It s not a big ask and an extension of current practices Doesn t need a big roll out or government endorsement like metabolic screening If all else fails, just do it
In Summary It is just another vital sign Removes the subjective assessment for cyanosis If abnormal, no change to current practices Few false positives 2-12/10000 births Femoral pulses are critical to detecting COA Pulse Ox screening allows us to decrease the diagnostic gap in detecting critical CHD
References 1. Thangaratinam S, Brown K, Zamora J, Khan KS, Ewer AK. Pulse oximetry screening for critical congenital heart defects in asymptomatic newborn babies: a systematic review and meta-analysis. Lancet. 2012 Jun 30; 379(9835): 2459 64. 2. Wren C, Reinhardt Z, Khawaja K. Twenty-year trends in diagnosis of life-threatening neonatal cardiovascular malformations. Arch Dis Child Fetal Neonatal Ed. 2008 Jan; 93(1): F33 5. 3. Prudhoe S, Abu-Harb M, Richmond S, Wren C. Neonatal screening for critical cardiovascular anomalies using pulse oximetry. Arch Dis Child Fetal Neonatal Ed. 2013 Jul; 98(4): F346 50. 4. Gardiner HM, Kovacevic A, van der Heijden LB, Pfeiffer PW, Franklin RC, Gibbs JL, et al. Prenatal screening for major congenital heart disease: assessing performance by combining national cardiac audit with maternity data. Heart. 2014 Mar; 100(5): 375 82. 5. Riede FT, Worner C, Dahnert I, Mockel A, Kostelka M, Schneider P. 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 of Pediatr. 2010 Aug; 169(8): 975 81. 6. Hammer CT, Wong KK. Supporting the need for newborn pulse oximetry screening. In: Canadian Paediatric Society, editor. Abstracts. Paediatr Child Health; 2014 Jun-Jul; 19(6): e41. 7. Ewer AK, Furmston AT, Middleton LJ, Deeks JJ, Daniels JP, Pattison HM, et al. Pulse oximetry as a screening test for congenital heart defects in newborn infants: a test accuracy study with evaluation of acceptability and cost-effectiveness. Lancet. 2011 Aug 27; 378(9793): 785 94. 8. Mahle WT, Martin GR, Beekman RH 3 rd, Morrow WR, Section on Cardiology and Cardiac Surgery Executive Committee. Endorsement of Health and Human Services recommendation for pulse oximetry screening for critical congenital heart disease. Pediatrics. 2012 Jan; 129(1): 190 2.
References 9. Centers for Disease Control and Prevention. Facts about critical congenital heart defects [Internet]. Atlanta: Centers for Disease Control and Prevention; 2015 May 21 [cited 2015 Dec 9]. Available from: http://www.cdc.gov/ncbddd/heartdefects/cchd-facts.html 10. Stanford Children s Health. Atrial septal defect (ASD) [Internet]. San Francisco: Stanford Children s Health; 2015a [cited 2015 Dec 9]. Available from: http://www.stanfordchildrens.org/en/topic/default?id=atrial-septal-defect-asd-90-p01766 11. Stanford Children s Health. Hypoplastic left heart syndrome [Internet]. San Francisco: Stanford Children s Health; 2015b [cited 2015 Dec 9]. Available from: http://www.stanfordchildrens.org/en/topic/default?id=hypoplastic-left-heart-syndrome-90-p01798 12. Stanford Children s Health. Tricuspid atresia [Internet]. San Francisco: Stanford Children s Health; 2015c [cited 2015 Dec 9]. Available from: http://www.stanfordchildrens.org/en/topic/default?id=tricuspid-atresia-ta-90-p01819 13. Stanford Children s Health. Coarctation of the aorta [Internet]. San Francisco: Stanford Children s Health; 2015d [cited 2015 Dec 9]. Available from: http://www.stanfordchildrens.org/en/topic/default?id=coarctation-of-the-aorta-90-p01770 14. Kemper AR, Mahle WT, Martin GR, Cooley WC, Kumar P, Morrow WR, Kelm K, Pearson GD, Glidewell J, Grosse SD, Lloyd-Puryear M, Howell RR. Strategies for implementing screening for critical congenital heart disease. Pediatrics. 2011; 128: e1-8.