Pulse oximetry screening - saving babies' lives

pulseoxPulse oximetry screening is a safe, painless and simple test that has been shown, in research studies involving almost half a million babies, to identify consistently babies with life-threatening heart defects (critical congenital heart defects or CCHD) before they become seriously unwell.  

The National Screening Committee's public consultation 

The UK’s National Screening Committee has been considering routine pulse oximetry screening for critical heart defects in newborn babies for a number of years. Recently, the National Screening Committee launched a public consultation on its decision not to offer pulse oximetry screening to all UK newborn babies. 

Pulse Oximetry

All the information about the National Screening Committee's consultation is on a dedicated website, but we hope this webpage that you are currently reading will simplify the consultation process and try to give information about important questions raised by the National Screening Committee. 

  1. What is pulse oximetry screening?
  2. Why does the National Screening Committee not want to recommend pulse oximetry screening for all babies?
  3. Submit your views 

If you have any questions about pulse oximetry screening or any of the information on this website, please contact the University of Birmingham's Professor Andrew Ewer, Professor of Neonatal Medicine

The National Screening Committee’s decision will affect every baby born in the UK (over 700,000 per year) and it is important that the views of parents, patients and clinical staff caring for newborn babies are heard.

It wants feedback on whether the evidence it has presented is sufficient to support its decision. It is asking for your opinion and, if you have a view on pulse oximetry screening, it is vital that we make sure the National Screening Committee is aware of it.

This is the only opportunity we will have to influence the National Screening Committee's decision.

The consultation is open until 9 August 2019; this is a great opportunity to air your views.

Take a look at the consultation website, read the consultation cover note and complete the consultation comments form after reviewing the associated documents on the consultation website. 

Please return your form to: screening.evidence@nhs.net

Take part in the consultation online – closing date 9 August 2019


What is pulse oximetry screening?

The screening process

Pulse oximetry screening is a simple test performed on babies before discharge from hospital. It takes less than five minutes and is completely harmless and painless.

The test is carried out using a pulse oximeter, a special machine that is used routinely throughout the world to measure the amount of oxygen in the blood. A small probe is wrapped around the baby’s hand and foot and connected to a small, handheld machine that measures the baby’s oxygen levels by shining a light through the skin.

Research at the University of Birmingham and by others has shown that by measuring blood oxygen levels in newborn babies, it is possible to identify the small number of babies who have an unidentified critical heart defect; these babies usually appear healthy at birth but often have lower oxygen levels.

The pulse oximetry test identifies babies with lower oxygen levels so we can check these babies very carefully to identify a possible heart defect before the baby becomes unwell.

In the USA, where pulse oximetry screening is routine for all babies, a large study has clearly shown that death from critical heart defects was reduced by one third in babies offered the screening compared with those who were not offered it.

Currently less than half of the babies born in the UK are offered this test and over half will not. Whether or not a baby has the test depends on the hospital of birth. If the National Screening Committee were to recommend this test then all babies born in the UK would be screened. 

Will my baby receive this test?

Whether your baby receives this test or not depends on where they are born. In a recent UK survey of hospitals that were not performing pulse oximetry screening, almost two-thirds are considering its introduction. Many are waiting for the National Screening Committee's decision before starting.

The charity Tiny Tickers recently introduced 'Tommy's campaign', which aims to provide pulse oximetry machines for those hospitals who would like to start pulse oximetry screening; machines have currently been provided in 35 hospitals. 

Other children’s heart charities, including the Children’s Heart Federation and Little Hearts Matter, have also been running campaigns advocating pulse oximetry screening.

A number of countries, including the USA and several European countries, have already recommended pulse oximetry screening. Professor Ewer led a large influential group of European doctors who strongly advocated routine pulse oximetry screening across Europe.

Why has this test been introduced in some hospitals?

Pulse oximetry screening has been shown to identify babies with life-threatening heart defects (otherwise known as critical congenital heart defects or CCHDs) and reduce deaths from these conditions by one-third. Pulse oximetry also identifies other serious conditions, such as infections and breathing problems, which allows earlier treatment for these problems also.

There is strong evidence to suggest that pulse oximetry identifies babies with these conditions early before they deteriorate. Many doctors think that this is a test that can save lives and reduce the time to diagnosis resulting in earlier treatment. 

This consultation is an opportunity for everyone, including doctors, nurses and parents, to express their views and experiences with this test.

What happens to babies who are currently screened with pulse oximetry?

UK research, including the National Screening Committee’s pulse oximetry pilot in 2015, has shown that what happens to babies who are screened is very consistent. 

POS infographicAbout seven in every 1,000 babies screened (0.7%) will have a positive test. More than half of the babies (six out of every 10 or 60%) who test positive are healthy and they just have slow adaptation to birth. Five out of these six babies will develop normal oxygen levels very quickly and will need no investigation or treatment.

Five out of every 10 babies who test positive (3.5 out of every 1,000 babies tested) will undergo further investigations and almost all will be admitted to the Neonatal Unit for further assessment. Most babies will have blood tests, X-rays and other investigations to try to find out the cause of the low oxygen levels.

Of the babies admitted to a Neonatal Unit after a positive test*:

  • One in 10 will have a heart problem and they will benefit from early diagnosis and treatment

  • Seven in 10 will have a breathing problem or infection and most will benefit from the test by early diagnosis and treatment of a potentially serious illness

  • Two in every 10 babies will be healthy (less than one in every 1,000 babies screened) and will have had any unnecessary tests that may have resulted in a delayed discharge from the Neonatal Unit

So about eight out of 10 babies (80%) who are admitted to the Neonatal Unit after a positive test will have a condition that is considered to require treatment which will have been detected early. By using pulse oximetry screening, this early detection can improve a baby’s chances of survival and long-term quality of life. 

In 2018, the National Screening Committee convened a work group of senior neonatologists and experts in public health in screening to decide on the balance between benefits and harms of pulse oximetry screening. They concluded that most babies who tested positive and were admitted to a Neonatal Unit will benefit. 

*Analysis from the National Screening Committee’s pulse oximetry pilot (pages 110-111)


Why does the National Screening Committee not want to recommend pulse oximetry screening for all babies? 

The National Screening Committee summarised its decision as follows:

‘…there is currently insufficient evidence to suggest that there is a greater benefit to babies with the inclusion of pulse oximetry than that afforded by the current screening programme alone. It is also noted that there are harms associated with screening and the further investigations following a positive screening result.’

This means that the National Screening Committee does not think that the evidence showing benefit of pulse oximetry screening is convincing.

What is the current screening programme for heart defects in newborn babies?

All babies are currently screened for heart defect while still in the womb (antenatal ultrasound) and following birth (postnatal clinical examination).

  • Antenatal ultrasound  between 2014 and 2017 in the UK, less than half (42%) of babies with heart defects that require intervention were identified before birth (2018 NICOR report, table 12a). Between different health regions in the UK there is great variability in the rate of identification – between 33% in the lowest performing regions and 62% in the highest – so some hospitals are much better at this than others
  • Postnatal examination – despite best efforts examination fails to identify about 45% of babies before collapse with critical congenital heart defects and up to 30% are sent home without diagnosis. Some of these babies will die and many will have a worse outcome as a result of late diagnosis. Research has consistently shown that when pulse oximetry is added to the existing programme the identification rate for critical congenital heart defects increases to between 90 and 95%

What does the National Screening Committee mean by ‘harms’?

  • In any screening programme the benefits must outweigh the harms. So, the benefits such as earlier diagnosis and treatment and reduction in death rate must be balanced against the harms of the screening test

Harms raised by the National Screening Committee

Parental anxiety – It is possible that some parents will be anxious if their baby does not pass the test. This information sheet explains what happens during screening to reduce any possible anxieties. In the Birmingham research study parents of babies who tested false positive were not significantly more anxious than those whose babies passed the test. What is your opinion on this?

Longer stay in hospital – Babies who have a serious condition will need to stay in hospital until they are better. Most babies who do not pass the test and are healthy are correctly identified within an hour or two and are not admitted to the neonatal unit. This is a short delay which rarely affects the time of discharge. Babies who test positive and are healthy who are admitted to Neonatal Unit (less than one baby per 1,000 screened) are usually discharged within 12 hours*.

Transfer to Neonatal Unit – About half of the babies who test positive (3.5 per 1,000 screened) are admitted to the Neonatal Unit.

Overdiagnosis or overtreatment – This is a problematic area as some of the non-cardiac condition (such as breathing problems and infections) are difficult to diagnose with absolute certainty. In the UK pilot and in a study from the University of Birmingham, about 80% of babies admitted to Neonatal Unit had a diagnosis of a potentially serious condition.

The working group formed by the National Screening Committee to address the issue of overdiagnosis and overtreatment decided that in most (six out of eight) of these conditions there was a clear benefit to early diagnosis with pulse oximetry and in one the benefits outweighed the harms. Only one condition did not benefit and this accounted for only one baby in over 32,000 screened*.

False positives – These are the babies who do not pass the test but do not have the condition screened for. In the strictest sense, all babies who do not have a critical congenital heart defect are false positives. However, there is an advantage to identifying the other non-cardiac conditions (see above) and so many people consider only the completely healthy babies to be false positives.

False reassurance or false negatives – Like many screening tests, pulse oximetry is not a perfect test and will miss some babies with critical congenital heart defects. The proportion of babies missed is reduced to less than 10% if pulse oximetry is added to existing screening.

*Analysis from the National Screening Committee’s pulse oximetry pilot (pages 110-111)


Submit your views

Have you recently had a baby? Was your baby offered pulse oximetry screening?

If yes – how did you find it? Did it make your anxious? Was the result positive or negative? 
Please share your experiences with the National Screening Committee

Are you having a baby soon?

Have you heard of pulse oximetry screening?
Does your hospital offer pulse oximetry screening?
Would you like the test to be offered to your baby?
Let the National Screening Committee know

Have you had a baby who had a serious heart defect?

How was the problem picked up?
Was there a delay in diagnosis?
Your experiences are really important

Do you care for newborn babies as a health professional?

Do you work in a hospital that provides pulse oximetry screening? If yes, what is your experience? Are there any drawbacks?
Is your hospital considering pulse oximetry screening?

Take part in the consultation online – closing date 9 August 2019


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