Pulse Oximetry Screening Has Not Changed Timing of Diagnosis or Mortality of Critical Congenital Heart Disease

Machine Learning-Based Critical Congenital Heart Disease Screening Using Dual-Site Pulse Oximetry Measurements

BACKGROUND

Oxygen saturation (Spo2) screening has not led to earlier detection of critical congenital heart disease (CCHD). Adding pulse oximetry features (ie, perfusion data and radiofemoral pulse delay) may improve CCHD detection, especially coarctation of the aorta (CoA). We developed and tested a machine learning (ML) pulse oximetry algorithm to enhance CCHD detection.

METHODS AND RESULTS

Six sites prospectively enrolled newborns with and without CCHD and recorded simultaneous pre- and postductal pulse oximetry. We focused on models at 1 versus 2 time points and with/without pulse delay for our ML algorithms. The sensitivity, specificity, and area under the receiver operating characteristic curve were compared between the Spo2-alone and ML algorithms. A total of 523 newborns were enrolled (no CHD, 317; CHD, 74; CCHD, 132, of whom 21 had isolated CoA). When applying the Spo2-alone algorithm to all patients, 26.2% of CCHD would be missed. We narrowed the sample to patients with both 2 time point measurements and pulse-delay data (no CHD, 65; CCHD, 14) to compare ML performance. Among these patients, sensitivity for CCHD detection increased with both the addition of pulse delay and a second time point. All ML models had 100% specificity. With a 2-time-points+pulse-delay model, CCHD sensitivity increased to 92.86% (P=0.25) compared with Spo2 alone (71.43%), and CoA increased to 66.67% (P=0.5) from 0. The area under the receiver operating characteristic curve for CCHD and CoA detection significantly improved (0.96 versus 0.83 for CCHD, 0.83 versus 0.48 for CoA; both P=0.03) using the 2-time-points+pulse-delay model compared with Spo2 alone.

CONCLUSIONS

ML pulse oximetry that combines oxygenation, perfusion data, and pulse delay at 2 time points may improve detection of CCHD and CoA within 48 hours after birth.

REGISTRATION

URL: https://www.clinicaltrials.gov/study/NCT04056104?term=NCT04056104&rank=1; Unique identifier: NCT04056104.

Screening for Critical Congenital Heart Defects in Sweden

OBJECTIVES

Early diagnosis of critical congenital heart defects (CCHD) improves survival. We evaluated the relative contributions of prenatal ultrasound, neonatal pulse oximetry screening (POS), and neonatal physical examination (NPE) to the early detection (before discharge) of CCHD in the context of increasing prenatal detection, and POS being a national standard since 2013.

METHODS

Retrospective, nationwide population-based study. All full-term live-born infants with CCHD in Sweden between 2014 and 2019 were included. CCHD was defined as a congenital heart defect requiring surgery or catheter-based intervention or resulting in death within 28 days of birth.

RESULTS

Of 630 infants, 89% were diagnosed before discharge or death, 42% prenatally, 11% from early symptoms, 23% by POS, and 14% from NPE after a negative POS. Four (0.6%) died undiagnosed before discharge and 64/630 (10%) were discharged undiagnosed, with 24/64 being readmitted with circulatory failure and causing 1 preoperative death. Coarctation was the most prevalent CCHD (N = 184), 25% of whom were detected prenatally (12% by POS and 29% by NPE). Two died undiagnosed before discharge and 30% were discharged undiagnosed. Transposition was the second most common defect (N = 150) and 43% were detected prenatally (33% by POS, 1 by NPE) and 2 died undiagnosed before POS. None was discharged undiagnosed.

CONCLUSIONS

POS and NPE remain important for the early detection of CCHD complementing prenatal ultrasound screening. Nevertheless, 1 in 10 with CCHD leaves the hospital without a diagnosis, with coarctation being the predominant lesion. Future research on CCHD screening should have a particular focus on this cardiac defect.

Trends in Delayed Diagnosis of Critical Congenital Heart Defects in an Era of Enhanced Screening, 2004-2018

OBJECTIVE

To describe trends in delayed diagnosis of critical congenital heart defects (CCHDs) with prenatal and postnatal screening advances.

STUDY DESIGN

We evaluated a retrospective cohort of live births with CCHD delivered between 2004 and 2018 from a statewide, population-based birth defects surveillance system in Massachusetts. Demographic information were obtained from vital records. We estimated timely (prenatal or birth/transfer hospital) and delayed diagnosis (after discharge) proportions by year and time periods coinciding with the transition to mandatory pulse oximetry in 2015.

RESULTS

We identified 1524 eligible CCHD cases among 1 087 027 live births. By 2018, 92% of cases received a timely diagnosis, most prenatally. From 2004 to 2018, prenatal diagnosis increased from 46% to 76% of cases, while hospital diagnosis decreased from 38% to 17%, and delayed diagnosis declined from 16% to 7%. These trends were consistent across all characteristics evaluated. Among cases without a prenatal diagnosis, the proportion with delayed diagnosis did not change over time, even after implementation of mandatory pulse oximetry screening. Prenatal detection increased the most among severe cases (treated or died in first month of life). Well-appearing newborns without prenatal diagnosis made up 79% of delayed diagnosis cases by 2015-2018. Delayed diagnosis was most common for coarctation.

CONCLUSIONS

While prenatal diagnosis of CCHD increased dramatically, there was no reduction in delayed diagnosis among postnatally diagnosed infants, even after pulse oximetry screening became mandatory. Pulse oximetry may not reduce delayed diagnosis in settings with high prenatal detection, and other strategies are needed to ensure timely diagnosis of well-appearing newborns.

Pulse Oximetry Screening: Association of State Mandates with Emergency Hospitalizations

We evaluated the association between implementation of state-mandated pulse oximetry screening (POS) and rates of emergency hospitalizations among infants with Critical Congenital Heart Disease (CCHD) and assessed differences in that association across race/ethnicity. We hypothesized that emergency hospitalizations among infants with CCHD decreased after implementation of mandated POS and that the reduction was larger among racial and ethnic minorities compared to non-Hispanic Whites. We utilized statewide inpatient databases from Arizona, California, Kentucky, New Jersey, New York, and Washington State (2010-2014). A difference-in-differences model with negative binomial regression was used. We identified patients with CCHD whose hospitalizations between three days and three months of life were coded as "emergency" or "urgent" or occurred through the emergency department. Numbers of emergency hospitalizations aggregated by month and state were used as outcomes. The intervention variable was an implementation of state-mandated POS. Difference in association across race/ethnicity was evaluated with interaction terms between the binary variable indicating the mandatory policy period and each race/ethnicity group. The model was adjusted for state-specific variables, such as percent of female infants and percent of private insurance. We identified 9,147 CCHD emergency hospitalizations. Among non-Hispanic Whites, there was a 22% (Confidence Interval [CI] 6%-36%) decline in CCHD emergency hospitalizations after implementation of mandated POS, on average. This decline was 65% less among non-Hispanic Blacks compared to non-Hispanic Whites. Our study detected an attenuated association with decreased number of emergency hospitalizations among Black compared to White infants. Further research is needed to clarify this disparity.

Coarctation of the aorta: Prenatal assessment, postnatal management and neonatal outcomes

Coarctation of the aorta (Coa) is a potentially life threatening diagnosis. It occurs in 0.3 per 1000 live births and accounts for 6-8% of all infants with congenital heart defects. Neonates with severe Coa may be completely asymptomatic at birth, as the ductus arteriosus can provide flow to the lower body. Those who are not diagnosed prenatally may be diagnosed only after constriction of the ductus arteriosus, when they present in cardiogenic shock. This group has a higher risk for mortality and morbidity relative to those diagnosed prenatally. Despite the increasing practice of universal pulse oximetry screening, many cases with significant coarctation of the aorta still go undiagnosed in the newborn period. In this article, we present the pathophysiology, diagnosis, presentation, treatment and outcomes of Coa.

Effects of universal critical CHD screening of neonates at a mid-sized California congenital cardiac surgery centre

INTRODUCTION

CHD affects over 1 million children in the United States. Studies show decreased mortality from CHD with newborn cardiac screening. California began a screening programme on 1 July, 2013. We evaluated the effect of mandatory screening on surgical outcomes at Loma Linda University Children's Hospital since 1 July, 2013.

METHODS

We evaluated all infants having congenital heart surgery at Loma Linda University Children's Hospital between 1 July, 2013 and 31 December, 2018. Primary target diagnoses include hypoplastic left heart syndrome, pulmonary atresia with intact ventricular septum, tetralogy of Fallot, total anomalous pulmonary venous return, transposition of the great arteries, tricuspid atresia, and truncus arteriosus. Secondary target diagnoses include aortic coarctation, double outlet right ventricle, Ebstein anomaly, interrupted aortic arch, and single ventricle. Patients were stratified by timing of diagnosis (pre-screen, screen positive, and screen negative). Primary end points were post-operative length of stay, operative mortality, absolute mortality, and actuarial survival.

RESULTS

The cohort included 274 infants. Of these, 79% were diagnosed prior to screening (46% prenatally). Only 38% of those screened were positive, with 13% of the cohort having a "missed diagnosis."

CONCLUSIONS

Primary targets were more likely to be diagnosed by screening (53%), while secondary targets were unlikely to be diagnosed by screening (10%) (p = 0.004). Outcomes such as length of stay, operative mortality, and actuarial survival were not different based on timing of diagnosis (p > 0.05). Despite late diagnosis, those not diagnosed until after screening did not have adverse outcomes.

Impact of pulse oximetry screening to detect congenital heart defects: 5 years' experience in a UK regional neonatal unit

Pulse oximetry screening (POS) has been shown to be an effective, non-invasive investigation that can detect up to 50-70% of previously undiagnosed congenital heart defects (CHDs). The aims of this study were to assess the accuracy of POS in detection of CHDs and its impact on clinical practice. All eligible newborn infants born between 1 Jan 2015 and 31 Dec 2019 in a busy regional neonatal unit were included in this prospective observational study. A positive POS was classified as two separate measurements of oxygen saturation < 95%, or a difference of > 2% between pre- and post-ductal circulations. Overall, 23,614 infants had documented POS results. One hundred eighty nine (0.8%) infants had a true positive result: 6 had critical CHDs, 9 serious or significant CHDs, and a further 156/189 (83%) infants had significant non-cardiac conditions. Forty-three infants who had a normal POS were later diagnosed with the following categories of CHDs post-hospital discharge: 1 critical, 15 serious, 20 significant and 7 non-significant CHDs. POS sensitivity for detection of critical CHD was 85.7%, whereas sensitivity was only 33% for detection of major CHDs (critical and serious) needing surgery during infancy; specificity was 99.3%.Conclusion: Pulse oximetry screening showed moderate to high sensitivity in detection of undiagnosed critical CHDs; however, it failed to detect two-third of major CHDs. Our study further emphasises the significance of adopting routine POS to detect critical CHDs in the clinical practice. However, it also highlights the need to develop new, innovative methods, such as perfusion index, to detect other major CHDs missed by current screening tools. What is Known: • Pulse oximetry screening is cost effective, acceptable, easy to perform and has moderate sensitivity and high specificity in detection of critical congenital heart defects. • Pulse oximetry screening has been implemented many countries including USA for detection of critical congenital heart defects, but it is not currently recommended by the UK National Screening Committee. What is New: • To our knowledge, this is the first study describing postnatal detection and presentation of all the infants with congenital heart defects over a period of 5 years, including those not detected on the pulse oximetry screening, on the clinical practice. • It emphasises that further research required to detect critical congenital heart defects and other major CHDs which can be missed on the screening tools currently employed in clinical practice.

Newborn Pulse Oximetry Screening at a Community Hospital: An 8-Year Experience

OBJECTIVES

To evaluate newborn pulse oximetry screening (POS) outcomes at a large community hospital and the impact of the recommended revised POS algorithm.

METHODS

A retrospective cohort study was performed to evaluate the results of POS in the well-infant nursery between 2012 and 2020. The POS results were obtained from an electronic platform. Chart review was completed for newborns with failed screens. The recommended revision to POS, no second rescreen, was applied to the data to evaluate screening outcomes.

RESULTS

Of the total 65 414 infants admitted to the well-infant nursery during this 8-year period, >99% (n = 64 780) received POS. Thirty-one infants failed POS (4.6 per 10 000 screened). All infants who failed POS were found to have a disorder, with 12 (39%) having critical congenital heart disease (CCHD), 9 (29%) having non-CCHD requiring further follow-up, and 10 (32%) having noncardiac conditions. One false-negative screen result was identified through the Maryland Department of Health Newborn Screening Follow-up Program. The positive predictive value of POS for those screened was 39% for CCHD, with a specificity of 99.97%. Eliminating the second rescreen in the POS algorithm would have resulted in an additional 5 newborns without CCHD failing POS, increasing the false-positive rate from 0.03% to 0.04%.

CONCLUSIONS

POS is an effective tool for identifying CCHD and secondary conditions. POS was successfully implemented with few missed screens and was highly specific. Elimination of the second rescreen in the pulse oximetry algorithm would have resulted in a minimal increase in false-positive results and faster evaluation of newborns with CCHD.