Newborn Screening for Critical Congenital Heart Defect (CCHD)

What is the importance of Critical CHD Diagnosis Before Leaving the Hospital?

When babies with an undiagnosed critical CHD leave the hospital, they might have very serious problems, such as cardiac collapse (when a baby’s heart stops working properly and can’t get oxygen to the body) or death within the first few days or weeks they are at home.

If a critical CHD is diagnosed before a baby leaves the hospital, doctors can provide care and treatment that may prevent later health problems or even death. They can also better plan treatment for a baby with a critical CHD, helping the baby have surgery or other treatment when he or she is stable, not in an emergency situation. Babies that have a critical CHD diagnosed after they leave the hospital tend to be admitted to the hospital more frequently, spend more time in the hospital, and have higher hospital costs compared with babies that had a critical CHD diagnosed in the hospital. Mandated critical CHD screening using pulse oximetry reduces early infant deaths from critical CHD by 33%, or 120 early infant deaths from critical CHD averted per year. Additional information about the importance of screening for Critical CHD is available at CDC.gov/NCBDDD.

How common is CCHD?

About 3 percent of all babies are born with a birth defect. Overall, nearly 1 percent of all newborns have a congenital heart defect (CHD). CHDs are the leading cause of birth defect-associated infant illness and death.

About 20 per 10,000 babies are born with critical congenital heart defects (CCHDs, also known as critical congenital heart disease), which are life threatening and require catheter-based intervention or heart surgery during the neonatal period. Delayed diagnosis of CCHD may result in the child having a poorer preoperative condition and worse cardiopulmonary and neurological outcomes after treatment.

Won’t CCHD be detected prenatally or by exam in the nursery?

Maybe not. Prenatal ultrasounds detect fewer than half of the cases of CCHD and predicting saturations based on visual examination of color is unreliable. Prior to discharge, some babies with CCHD will have normal exams and not appear cyanotic.

Often the ductus arteriosus does not close until after the baby goes home. Before closing, the ductus arteriosus may provide a significant amount of blood flow to the lungs or body. As a result, babies with CCHD can quickly decompensate when the ductus arteriosus closes. Pulse oximetry can accurately detect the lower oxygen saturations associated with CCHD with ductal-dependent systemic or pulmonary blood flow.

Why is CCHD screening considered to be part of newborn screening?

Newborn screening is a public health program intended to ensure that all newborns are tested for specific conditions, regardless of where they are born and their insurability. The program began in the 1960s as a way to detect metabolic disorders using dried-blood spots. Today, nearly all newborn babies have a blood spot taken, which is sent to a centralized laboratory for evaluation. The goal of newborn screening is to identify conditions that are not associated with clinical signs or symptoms during the newborn period but that benefit from early detection. Each state determines which conditions are included in newborn screening.

As of 2018 all states added CCHD screening as part of routine newborn screening, but the role of state health departments in supporting CCHD screening adoption and monitoring of screening rates and outcomes varies. Unlike other current newborn screening tests, the health care team should assure diagnostic, and when necessary, treatment services are provided to those babies with a failed CCHD screen prior to discharge home. It is also important for health care to be aware of the specific requirements and recommendations for screening and the reporting of results.

The AAP recommends that all newborns be screened for CCHD.

What CCHD screening algorithm should I use?

Check your state requirements for CCHD screening first. State profiles are available on the NewSTEPS website. In the absence of a state-recommended algorithm, the AAP-endorsed CCHD screening algorithm should be used. . A graphical presentation of the algorithm along with a detailed description is available on the Centers for Disease Control and Prevention Website for the National Center for Birth Defects and Developmental Disabilities.

Which babies should be screened?

All newborns at risk for undetected CCHD should be screened. In other words, the only babies who do not need to be screened are those who are already known to have CCHD, such as those identified by prenatal ultrasound or who have already had an echocardiogram. The algorithm referenced above was developed primarily for healthy, full-term newborns. Please see Screening in Special Settings for information on premature infants, newborn infants who are sick or have other congenital malformations, or infants born at high elevation.

There are some very uncommon reasons that CCHD screening might not be done (e.g., babies who have an echocardiogram prior to discharge to home from the nursery or babies who have such serious medical conditions that no intervention would be done if CCHD were identified). Some parents might also refuse CCHD screening. In that case, parents should be educated about the benefits of screening and, if they still refuse, the refusal should be documented in the medical record.

To avoid missing screening opportunities, plan to screen all eligible newborns. Also, be aware of any state-specific rules, which may require that all newborns be screened regardless of any prior testing or diagnoses.

Screening should begin after 24 hours of age or shortly before discharge if the baby is less than 24 hours of age. Waiting until 24 hours of life will decrease the false-positive results. The screening should occur in the right hand and either foot. If using only one pulse oximeter, test one right after the other. Testing should occur with the patient breathing room air.

The baby passes screening if the oxygen saturation is 95 percent or greater in the right hand or foot and the difference is three percentage points or less between the right hand or foot. The screen is immediately failed if the oxygen saturation is less than 90 percent in the right hand or foot. If the oxygen saturation is greater than 90 percent and less than 95 percent in the right hand and foot, or there is more than a 3 percent difference between the right hand and foot, then repeat the screen in one hour and follow the same process as above. Rarely, some babies will require three screens (e.g., the initial and two repeat screens, all separated by one hour). A baby whose oxygen saturation measures 90 percent to less than 95 percent in either the right hand and foot, Or who has more than a 3 percent difference between the right hand and foot after the third screen, will have failed screening.

Who should perform the screening?

CCHD screening should be conducted by individuals who have pulse-oximetry testing within their scope of practice, who are trained in the use of pulse oximetry and the CCHD algorithm, and who regularly use pulse oximetry for other purposes. Ultimately, the health care provider of record for each newborn is responsible for assuring that screening was appropriately completed.

What pulse-oximetry equipment should I use?

Many pulse oximeters are currently available, and most hospitals have pulse oximeters already available. Only hospital-grade pulse oximeters designed for use in neonates should be used for CCHD screening. It is important that the probes used are designed for use in newborns and that the manufacturer specifically recommends them for the particular pulse oximeter you are using. Using reusable probes can decrease the overall cost of CCHD screening. In addition, using a device that provides a waveform can make it easier to tell when the pulse oximeter is appropriately tracking the oxygen saturation. Some pulse oximeters report a perfusion index. This is not currently used in the algorithm. Some device manufacturers are developing pulse oximeters with the CCHD screening algorithm embedded. This is not necessary, although it could help simplify the screening process.

If an asymptomatic infant fails CCHD screening using pulse oximetry, what is the likelihood that CCHD or some other serious disease is present?

In most cases when of a “positive” screen, a newborn may have a CCHD or another potentially serious and treatable condition. Examples include, a noncritical congenital heart defect, sepsis, other infection, persistent pulmonary hypertension, parenchymal or anatomic pulmonary disease, transient tachypnea of the newborn, hypothermia, and hemoglobinopathies. It is important to recognize that a baby with a failed screen can look completely well on exam but have a significant underlying medical problem.

What are the oxygen saturation cut-off levels?

If the oxygen saturation level is below 90 percent in both the right hand and either foot, it is considered a failed test, according to the AAP-endorsed CCHD screening algorithm. If the oxygen saturation level is at least 95 percent for readings on both the right hand and either foot, it is considered a passed screening as long as the difference between the foot and right-hand readings is 3 percent or lower.

How should I track screening completion and outcomes?

In addition to recording the screening results in patients’ charts, all birth centers should have a log to track the completion of screening and screening results. Many of the most effective logs are computer based. If it is not possible to have a log within the electronic medical record that you use, a simple one utilizing a spreadsheet can be sufficient. However, paper-based logs can be used if it is not possible to track screening electronically.
Using such logs is an important component of quality improvement to assure that all babies are appropriately screened. Elements to include in the log are: the baby’s unique identifier, the age of the baby when screened, the exact pulse-oximetry results and the limb where they were obtained, whether the screen was considered to be passed or failed, and, if failed, a description of the subsequent evaluation and final specific diagnosis (e.g., normal, specific type of CCHD, or the other specific cause of the hypoxemia, such as sepsis or pneumonia). If necessary, the reasons for not screening a baby should also be recorded (see CCHD Screening Data Collection and Management). In the setting of a busy nursery, it can be easy to misclassify a screening result as passed or failed. Therefore, cutoffs for normal and abnormal should be included on the log, and routine audits of the data should be performed.

Who will pay for the CCHD screening?

As of now, there is not a separate reimbursement available for CCHD screening. CCHD screening is, therefore, part of the bundled services that all newborns should receive. However, services provided after a failed CCHD screening (e.g., echocardiograms) are typically reimbursed. If the abnormal screen, meaning they have repeated the screen per protocol, remains abnormal and results in a cardiology work up, those services are appropriately billed and paid.

Developing strategies to efficiently administer CCHD screening can significantly reduce hospital costs. For example, utilizing reusable pulse-oximetry probes reduces the direct cost of screening. Bundling the screening with other care activities at the time of screening can reduce the staff time required to screen. Using log forms, as described above, can help balance work activities and patient flow in the newborn nursery to further improve efficiency.

Do I need to obtain consent from parents before screening?

CCHD screening is considered a part of routine newborn nursery care. Many birthing centers incorporate the consent for screening as part of the overall consent for managing the infant. Therefore, no specific consent is needed. However, informing parents ahead of time that the CCHD screening will occur can help decrease anxiety in the event of a failed screen. Communicating with parents is also an important component of public education, which can help increase support for CCHD screening.

Although signed consent for CCHD screening is not required, some hospitals may require signatures confirming that screening was performed. Refer to your hospital’s policies and procedures.

What should I do after a failed screen?

After a failed screen, the first step is to examine the infant to make sure the baby is hemodynamically stable. Once it is confirmed that the baby is stable, begin the process of evaluation for hypoxemia. Depending on the status of the baby, this could involve evaluating for sepsis or pneumonia. Any signs or symptoms of CHD should prompt rapid evaluation, including potential urgent transfer to a center with advanced care capabilities.

If the baby is asymptomatic and otherwise well, with no obvious cause for hypoxemia, a cardiologist or neonatologist should be consulted and an echocardiogram should be performed. Newborns should not be discharged home until the underlying reason or hypoxemia has been identified or the hypoxemia has resolved. Remember, these babies will often appear normal and have no clinical findings other than the low oxygen saturation. Still, a careful and thorough evaluation is necessary.

What should I do if there are no pediatric cardiologists or pediatric echocardiography in my hospital?

Not all causes of hypoxemia are necessarily cardiac in nature, but a thorough evaluation should be performed. Plans should be made regarding the management of stable infants who have failed CCHD screening. This could range from echocardiogram by telemedicine or transferring to another center for further evaluation. Although babies may appear well at the time of the failed screen, those with CCHD may rapidly decompensate as the ductus arteriosus closes, so follow-up on the failed screen should happen before a baby is discharged, rather than as a scheduled follow-up.

If this is newborn screening, what is the role of the public health department?

CCHD screening is a component of newborn screening. This means that the screening should be universal for all newborns. Unlike blood-spot screening for metabolic conditions, CCHD screening is a point-of-care test. This means that all of the screening happens within the hospital. Unlike newborn hearing screening, another point-of-care newborn screening test, diagnostic follow-up for those with a failed screen must occur prior to discharge home. States have taken different approaches to CCHD newborn screening. Some mandate that the CCHD screening should be done but leave implementation up to health care providers. Other states take a more active role, mandating how and when CCHD screening should occur or what data to report to the health department.

Does a passing CCHD screen mean that there is no critical congenital heart defect?

CCHD screening with pulse oximetry is used to detect 12 CCHD conditions and six non-CCHD, secondary conditions. Conditions Detected Via Screening for CCHD With the Use of Pulse Oximetry:

Core Conditions

• Coarcation of the aorta
• Double-outlet right ventricle
• Ebstein’s anomaly
• Hypoplastic left heart syndrome
• Interrupted aortic arch
• Pulmonary atresia
• Single ventricle (not otherwise specified)
• Tetralogy of Fallot
• Total anomalous pulmonary venous return
• D-transposition of the great arteries
• Tricuspid atresia
• Truncus arteriosus
• Other critical cyanotic lesions not otherwise specified

Secondary conditions (non-CCHD):

• Hemoglobinopathy
• Hypothermia
• Infection, including sepsis
• Lung disease (congenital or acquired)
• Noncritical congenital heart defect
• Persistent pulmonary hypertension
• Other hypoxemic conditions not otherwise specified

As with any screening test, both false positives and false negatives can occur. The screening algorithm was developed to balance the harms of false positives (e.g., worry to the family, unnecessary testing) against the harms of false negatives (e.g., delayed detection of CCHD).

Health care providers should not consider a passed normal CCHD screen to mean that the baby does not have CCHD. The screen is not intended to replace current clinical care; instead, it should augment care to increase case detection. In addition, it is critical to remember that CCHD screening does not detect all cases of serious (CHD). For example, coarctation of the aorta can be life threatening in early infancy, but may not be associated with hypoxemia.

Are there toolkits that can help me with implementation?

Several toolkits have been developed. The University of Wisconsin and Children's National Medical Center have comprehensive toolkits, including provider and family educational materials, available on the Internet. In addition, the Newborn Screening Technical assistance and Evaluation Program (NewSTEPs) provides technical assistance webinars, legislative updates, educational resources, news and events, and data collection specific to CCHD.

Why is it important to collect and record CCHD screening data?

As with any other medical activity, screening results and any subsequent activity should be recorded in the child’s medical record. Tracking screening results helps with quality-assurance efforts, public health surveillance and improving the process of CCHD screening overall.

Other than for direct medical care, how can screening results be used?

CCHD screening is a component of newborn screening. That means that all newborns should be appropriately screened. Therefore, all birthing facilities should have systems in place to regularly audit charts to assure that high-quality screening is routinely conducted. Missed screening or misclassified screening results should prompt a root-cause analysis to improve systems of care. If a missed screening has been identified, the baby’s primary care provider should be notified immediately.

Although CCHD screening has already been shown to improve health outcomes, ongoing assessment and optimization of these algorithms is done to improve the case detection rate and lower the false-positive rate. Many states and other agencies are collecting data on the process of screening and screening outcomes. Similar work is also being conducted to develop new approaches to improve care coordination after failed CCHD screening. It is important for health care providers to be good partners with these public health activities, including timely reporting of requested data, to assure that CCHD screening programs meet the goal of efficiently decreasing morbidity and mortality associated with CCHD.

What data should be recorded?

At a minimum, the data recorded within the medical record should include: the age of the baby at the time of screening; the specific values of each oximetry result, including the extremity from which it was obtained; whether the screen was deemed a pass or fail; and where the screening took place. If the screening was not done, then the reasons should be documented. All subsequent activities related to a failed screen (e.g., exam, echocardiogram) should also be documented. As described in the preceding section, documentation logs can be helpful in assuring that all newborns are appropriately screened. In addition, some health departments have specific requirements regarding the data to be reported that should also be included (see Topic 2: Implementation of CCHD above).

Should I modify the screening algorithm if I am at high altitude?

The partial pressure of oxygen decreases with increasing elevation. As a result, children born at high altitude (e.g., >800 meters) may have lower pulse-oximetry levels than those born at sea level. The CCHD screening algorithm was based on studies done near sea level. Therefore, there may be more false positives among babies screened at high altitude. However, more research should be done before modifying the algorithm if you are at high level. Providers are encouraged to track data regarding all screening activity to help with any necessary revisions in the future.

Should babies born at home be screened?

The AAP Policy Statement regarding Planned Home Birth recommends CCHD screening for planned home deliveries. The same CCHD screening protocol used for hospital births should be used in the home birth setting, keeping in mind that it is most reliable if performed 24 hours or more after birth. Those involved with home births should assure that any necessary repeat screening is done in a timely manner and that newborns with failed screenings have an expeditious evaluation for CCHD and other causes of hypoxemia.

What should be done for full-term babies with systemic disease or congenital anomalies?

Infants with systemic disease or with congenital anomalies can fall through the cracks of the usual CCHD screening process as their care diverges from that of otherwise well babies. Missed screening can occur when a newborn is moved from the normal nursery to an intensive care setting or is transferred between institutions. CCHD screening should be performed prior to discharge home unless performed previously during the baby’s care. CCHD screening does not need to be performed prior to discharge if echocardiography has been performed as part of the infant’s care.

Should infants in the NICU be screened?

Although premature infants usually have pulse-oximetry measured as a routine part of their management and are observed for longer periods than asymptomatic term infants, there is the possibility that some forms of CCHD may go undetected even in the NICU. Routine care in the NICU typically does not involve pre- and post-ductal oxygen saturation measurements, leading to the possibility of missing a case. In addition, the presence of lung disease and other illness makes the interpretation of saturation data much more complex in these infants and CCHD screening at 24 hours after birth is often not possible.

For those infants who have not had echocardiography performed as part of their care, the CCHD screening protocol should be followed once they have been weaned from supplemental oxygen. CCHD screening does not need to be performed prior to discharge if the baby has already had an echocardiogram. Note that some state newborn screenings mandate that all infants undergo CCHD screening, regardless of prior receipt of an echocardiogram. This simplifies the process of making sure all newborns are tested. Please make sure to follow the rules in place covering your practice setting.

Should babies be screened in primary care offices if they were not screened in the nursery?

CCHD screening allows the detection of CCHD during the asymptomatic period prior to closure of the ductus arteriosus. The asymptomatic window for these infants is of variable duration, and babies discharged with unrecognized CCHD often become symptomatic within the first two weeks after birth. Because CCHD screening can be performed in the primary care office, screening can be considered at the first newborn outpatient visit for those babies who were not screened. Pediatricians who opt to perform CCHD screening in the office should have a plan in place for further evaluation for infants who need repeat pulse-oximetry measurements or who have a failed screen. The focus of screening, however, should be in the newborn nursery to avoid the need for outpatient CCHD screening.