Crying baby
Photo for illustrative purposes only Image Credit: Unsplash

A sallow complexion tinged with blue comes into focus as the baby wails. His tiny body with swollen extremities shuddering, his stomach flexing as he regurgitates milk – he is suffering from Blue Baby Syndrome, a condition where low oxygen levels cause a change in skin colour.

Dr Siddharth Arora, PICU Specialist, General Paediatrics, Medcare Women and Children Hospital, explains: “Blue Baby Syndrome is when a baby’s skin has a bluish discolouration, sometimes especially when they cry. This condition is characterised by bluish or purple skin and this is known as cyanosis.” In Greek, ‘cyanoses’ literally means ‘dark blue’. “The blue tinge is caused by lack of oxygen in the blood flowing in the body,” he explains.

Blue Baby Syndrome is especially noticeable in the nailbeds and around the lips, tongue and earlobes where the skin is thinner.

- Dr Anita Ravi Kumar

Dr Anita Ravi Kumar, Specialist Peadiatrician Prime Medical Center, explains: “Blue Baby Syndrome is especially noticeable in the nailbeds and around the lips, tongue and earlobes where the skin is thinner.”

The condition can occur due to a number of congenital (present at birth) heart formation defects or environmental factors.

Typically, at what age does the condition present itself?

This depends on the underlying condition causing the defect, explains Arora. However, usually the condition affects early infancy.

What causes Blue Baby Syndrome?

Ravi Kumar says that in babies, congenital cyanotic heart disease, which is an umbrella term for a group of heart issues present at birth, is the main cause of this syndrome. “There may be mixing of oxygenated and deoxygenated blood due to defects in the heart walls or outflow obstruction so that sufficient blood doesn't reach the lungs to be oxygenated,” she adds.

Dr Arora explains that while in the case of structural heart defects, one can see an immediate chain of events; if it’s an acquired issue, it may take up to six months to present.

  • Structural heart defects: In this case, the lungs and heart are not able to provide oxygenated blood to the body. This is evident at birth itself. However, in some cases the ‘bluishness’ becomes more prominent and so difficult to ignore by the end of the first or second month.
  • Chemical issues such as methemoglobinemia: These may show up by about the sixth month.

Congenital heart defects

There are a few subtypes of congenital heart defects that can cause abnormal mixing or supply of oxygenated blood from the lungs with the deoxygenated blood returning from body. Depending on the level and grade of severity, the bluishness will occur. Most common lesion is the Tetralogy of Fallot - which involves the heart defect with four features including a narrow pulmonary artery, a thick right ventricle, an aorta that connects to both the right and left ventricles, and a hole in the ventricle wall, explains Dr Arora. It does not allow for regular blood flow to the heart.

Other defects include:

Transposition of the great vessels - a birth defect of the heart in which the two main arteries carrying blood out of the heart – the main pulmonary artery and the aorta – are switched in position, explains Centres for Disease Control and Prevention (CDC).

Tricuspid atresia: CDC explains this as a birth defect of the heart where the valve that controls blood flow from the right upper chamber of the heart to the right lower chamber of the heart doesn't form at all.

Total anomalous pulmonary venous connections: This is a birth defect of the heart in which the veins bringing blood back from the lungs don’t connect to the left atrium as per usual. Instead they go to the heart by way of an abnormal connection.

Persistent ductus arteriousus (PDA): This is a hole that allows the blood to skip the circulation to the lungs, explains American Heart Association; every baby in the womb has one. But once they are born, this hole is supposed to close within a day or two. Small PDAs often close on their own within the first few months of life, explains Arora. “Most children can have the PDA closed by inserting catheters (long thin tubes) into the blood vessels in the leg to reach the heart and the PDA, and a coil or other device can be inserted through the catheters into the PDA like a plug,” it adds.


This is a form of haemoglobin that has been oxidised and cannot bind oxygen. As a result it cannot deliver oxygen to the tissues. It can be a congenital or an acquired condition.

The majority of people with congenital methemoglobinemia are asymptomatic except for cyanosis (only of cosmetic significance), but some forms may have serious morbidity, says Arora.

High levels of ingested nitrates and nitrites have been associated with methemoglobinemia. Some examples include making baby formula from well water, using unclean root vegetables, exposure to some mushroom types, antifreeze, aniline dyes.

- Dr Siddharth Arora

Acquired methemoglobinemia can be severe or even fatal, depending on the proportion of methemoglobin. “High levels of ingested nitrates and nitrites have been associated with methemoglobinemia. Some examples include making baby formula from well water, using unclean root vegetables, exposure to some mushroom types, antifreeze, aniline dyes, while most commonly implicated medications include antimalarials like dapsone, topical anesthetic agents (benzocaine, lidocaine, prilocaine),” explains Dr Arora.

Dr Ravi Kumar adds: “The treatment is medical. Oxygen therapy and transfusions may be required. Baby foods and water containing high levels of natural nitrates must be avoided.”

What’s an unhealthy nitrate level?
Nitrates are present in fertilizer as well as explosives. Carried by rain or irrigation this compound may make it into the soil down to ground water or into other sources of drinking water. Human and animal wastes can also add to nitrates in ground water. The compound does have some uses – it is used to treat angina, chest pain caused by heart disease. Wisconsin Department of Health Services explains that if a private well has nitrate levels above 10 milligrams per liter (mg/L), then pregnant and breastfeeding women should use bottled water instead of the well water.

What are the symptoms?

Here’s a look at some general symptoms – these may vary depending on the cause of the ailment, explains Dr Arora.

Common and not so dangerous:

  • Always cranky and crying,
  • Excess salivation, diarrhoea, vomiting,
  • Feeding tantrums,
  • Slow growth,
  • Clubbed’/swollen fingertips and toes,
  • Murmuring sounds in baby heart, and
  • Fever.

Dangerous symptoms:

  • Weight loss,
  • Cold baby,
  • Rapid breathing,
  • Seizures,
  • Racing heartbeat,
  • Poor pulse detected by the doctor, and
  • State of shock and fainting in extreme cases.

What are the tests undertaken to diagnose Blue Baby Syndrome?

It’s not enough to rely on anecdotal evidence in this case. There are a number of tests that must be undertaken, explains Dr Arora.

Blood examinations such as a full blood count, blood gasses – a group of tests to measure the pH and the amount of oxygen and carbon dioxide resent in blood sample.

Tests for lungs:

  • Chest X-ray
  • Oxygen saturation.

Tests for the heart:

  • Electrocardiogram (EKG).
  • Echocardiogram
  • Cardiac Catheterisation.

What’s the prognosis for someone with Blue Baby Syndrome? What are the treatments?

While treatment depends on the underlying cause, it involves prevention by way of prenatal tests and acute observation. Other important treatment routes are:

  • Some medications and counselling might be required for inherited methemoglobinemia.
  • For acquired causes, ascorbic acid or Vitamin C, methylene blue or oxygenation are used, depending on the case.

In case of structural issues, explains Dr Arora, corrective and palliative heart surgeries will be done. Some of the underlying heart defects have very good surgical outcomes with a normal life longevity if diagnosed and done at the right time in infancy.

Did you know?
American cardiologist Helen Taussig founded paediatric cardiology and her specialisation was blue baby syndrome. One of the chief reasons of which is a congenital heart condition. She used fluoroscopy – a new X-ray technique at the time – to discover that babies with such conditions had leaking septums and an underdeveloped artery leading from the heart to the lungs.
With her years of research and experience, Taussig came up with an idea for a surgical procedure to fix the issue. In 1944, she and another surgeon performed the operation for the first time, with successful results. They then repeated it successfully on two more patients. Soon, the technique was used in operation theatres worldwide.