Pulse Oximetry screening for Cardiac malformations in the neonate Majd Abu-Harb September 2014

Congenital Cardiac malformations 6-10% of all infant deaths 74% of all CCM are diagnosed in infancy and most of these present during the neonatal period 96% of those who survived infancy will go on to survive into adulthood

Congenital Cardiac malformations Many babies are asymptomatic at birth More than 50% babies with CM may be missed by neonatal exam* Earlier discharge reduces time-window for signs and symptoms to develop * Wren et al. Arch Dis Child Fetal Neonatal Ed 1999;80:F49-F53

Current Timing of Diagnosis of Congenital Heart Disease

Modes of presentation in the neonate Left heart obstruction Right heart obstruction Abnormal connections

Modes of presentation Left heart obstruction Right heart obstruction Abnormal connections Heart failure

Modes of presentation Left heart obstruction Right heart obstruction Abnormal connections Heart Failure Cyanosis

Left heart obstruction Heart Failure Coarctation of the Aorta

Right heart obstructive lesions Cyanosis Diminished pulmonary blood flow

Cyanosis Abnormal connections Problem with mixing Transposition of the great arteries

Newborn screening NN check: murmur abnormal pulses

How significant are neonatal murmurs?

Our audit of early neonatal murmurs (2008-9) All babies born in Sunderland undergo new born check in hospital even if delivered at home All babies with murmurs can be evaluated prior to discharge

Retrospective - hospital based All births over 2 year Total births 6874 Exclusions: prenatal diagnosis preterm < 35 wks symptomatic prior to NN examination admissions to NICU 6560 included in the analysis

Of 6560 babies 70 had murmurs (Prevalence 1%) Age of baby when murmur was detected 12-36hrs Hospital stay: range hrs ( mode 21.5hrs) Of those with murmurs 23 had structural CM ( 33%) Our audit

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Screening Antenatal : Anomaly scan detection rate variable NN check Pulse oximetry: - Clinically undetectable low oxygen levels present in the majority of critical CM - Pulse oximetry may detect babies with Critical CM early, before they collapse

Measurement of oxygen saturation once in one foot of all babies after 2 hrs and before discharge

The oxygen saturation study All babies whose oxygen saturation below 95% had echocardiography 2 year birth cohort based at Sunderland April 1999-March 2001 Total live births: babies eligible for measurement 5626 (98.3%) measured

Oxygen saturation study Total births 6166 ( 49 ) CHD Babies with Sat. measured 5625 ( 10 ) CHD 296 Sat. low ( 12 ) Other significant pathology

Oxygen saturation study Babies with Sat. measured 5625 ( 10 ) CHD 296 Sat. low ( 12 ) Other 10 Respiratory 2 CNS 7 Murmur 3 No murmur 1 Coarctation 2 Transposition

Critical Cardiac malformations ~ 1.7/1000 live births Estimated 1200 new cases per year in England and Wales May only be recognised when babies collapse Hypoplastic Left heart Syndrome (HLHS) Pulomanry atresia with Intact ventricular septum (PA /IVS) Interrupted Aortic Arch (IAA) Transposition of the Great Arteries (TGA) Those dying or undergoing operation/intervention before 12 weeks of age with the following –PA with VSD –Coarctaion of the aorta (CoA) –Aortic stenosis (AS) –Total anomalous pulmonary venous connection (TAPVC)

2007 -Systematic review ; 8 studies patients Thangaratinam et al. Arch Dis Child Fetal Neonatal Ed 2007,92:F176-F180 “ More Larger studies needed to define test accuracy” 2011 PulseOx: a test accuracy study Ewer et al. The Lancet, Volume 378, Issue 9793, pages , 27 August babies screened ( of which 24 cases had Critical CM) Test positive -18/24 critical cases - 14 non-critical CM Accuracy for Critical CM : sensitivity 75% vs 50% antenatal us False negatives : 6 Critical CM ( 4 of which detected on AN screen ) False positives: 169 (0.8%) of these 6 had significant CM, 40 had other conditions including pneumonia Oximetry studies

2013 -Neonatal screening for critical CM using pulse oximetry Prudhoe et al Arch Dis Child Fetal Neonatal Ed 2013;98:F346-F previous studies listed –published birth cohorts Single centre study ( ) babies screened ( of which 27 had Critical CM) Test positive - 5/27 critical cases - 5/50 serious cases “ Routine pulse oximetry did not prevent five babies with critical and 15 with serious anomalies being discharged undiagnosed. Results from screening over babies have now been published, but this total includes only 49 babies with transposition, and even smaller number of rarer anomalies” 3 more studies have been published since ….. Oximetry studies

What do have oximetry screening (OS) studies in common? OS is effective in significant hypoxaemia i.e. most obstructive right heart lesions OS is not good at detecting Coarctation of the aorta The advantage of detecting non-cardiac serious illnesses

Practical issues Antenatal detection rate of CM False positive rate and impact on: - admission - workload - parental anxiety Timing of screening Acceptability and cost-effectiveness Wider implementation of OS in the UK?

Birmingham Women’s Hospital data 40 month period Live births : Total admissions 3552 of which 1651 were unexpected - 208/1651 (12.6%) for test +ve OS - Echo was performed in 61/ /208 had significant clinical condition 17 CM ( 9 critical) 55 pneumonia 30 sepsis 12 PPHN Therefore 1/8 of the unexpected admissions was due to positive OS but less than third of these had echo performed Singh A et al. Arch Dis Child Fetal Neonatal Ed 2014;99:F297-F302

Conclusions Routine pulse oximetry screening: is feasible and acceptable to parents and staff adds value to existing screening procedures is likely to identify cases of Critical CM which would otherwise go undetected has the additional advantage of detecting other serious ( non- cardiac ) illnesses

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