Cyanosis is characterized by bluish discoloration of skin and mucous membranes. Cyanosis is usually a sign of an underlying condition rather than being a disease in itself.
The most common symptoms of the condition are bluish discoloration of the lips, fingers, and toes.
Symptoms of cyanosis can be broken down into those for central and peripheral cyanosis. (1-5)
Symptoms of central cyanosis
This is manifested by bluish or purple discoloration of tongue and lips and mucous membranes of the mouth.
It is seen in diseases of the heart or lungs and in abnormal haemoglobin conditions like methemoglobin and sulfhemoglobin etc. Here cyanosis is caused due to desaturation of central arterial blood due to diseases of the heart and lungs.
This deoxygenated venous blood instead of going to the lungs for oxygenation moves to the general blood circulation of the body leading to symptoms of cyanosis.
Usually central cyanosis is accompanied with features of peripheral cyanosis.
There may be other features like breathlessness, shortness of breath, bluish or purple discolouration of the oral mucous membranes, rapid and shallow breathing etc.
The hands and feet are usually normal temperature or warm. They may be cold if there is concomitant peripheral cyanosis.
Symptoms of peripheral cyanosis
This is caused by decreased blood circulation in the peripheral organs and limbs. This may occur due to stasis or stagnation of blood and excessive extraction of oxygen from the blood making it deoxygenated and manifesting as cyanosis.
The affected areas turn bluish or purple and are cold to touch. It is commonly seen in the nail beds.
The condition resolves with gentle warming. There is no bluing of the mucous membrane of the mouth.
Age and onset of cyanosis
Cyanosis that occurs due to a congential or birth defect of the heart usually begins at birth or within the first few years of life.
In heart failure, lung embolism, pneumonia or acute severe attack of asthma, the cyanosis may have a sudden or abrupt onset as the patient “begins to turn blue” due to lack of oxygen.
On the other hand patients with chronic obstructive lung disease or COPD often develop cyanosis gradually over many years.
Patients with a long history of COPD or asthma or other lung diseases are prone to develop cyanosis
Symptoms of cyanosis in infants
Infants with cyanosis get tired or sweat while feeding and show lack of weight gain.
They may be born with a low birth weight. They may be irritable and often feel floppy or limp.
There is flaring of the nostrils as evidence of laboured breathing. Some babies may grunt or emit a noise with each breath.
Symptoms of cyanosis in children
Children with cyanotic heart diseases also assume a squatting position after physical activity to relieve breathlessness.
Fainting spells are common with children who have cyanotic heart diseases. Children with congenital heart disease are also prone to repeated chest infections.
Other symptoms of cyanosis
Other symptoms of cyanosis include the following (1-5):
- There may be breathlessness, difficulty breathing and rapid shallow breathing. This may happen suddenly in cases of pulmonary emboli, pulmonary oedema or sever attack of asthma.
- Other symptoms include chest pain. If cyanosis is caused due to pleural effusion (collection of fluids around lungs), pneumonia or pulmonary embolism there may be chest pain. Pulmonary oedema also causes a dull, aching chest tightness.
- There is accompanying fever in patients with pneumonia or pulmonary emboli.
- Those with heart failure may also cough up a pink frothy sputum or dark mucus.
- There is usually thickening of the last joint of the fingers. This gives them a club like appearance and is called clubbing of fingers.
This occurs due to long standing oxygen deprivation in certain heart and lung diseases. Cyanosis is often accompanied by clubbing.
- There is general tiredness or weakness in patients who suffer from long term cyanosis. There may be episodes of headaches as well.