The principal function of the respiratory system is to get oxygen into the body and to release carbon dioxide (the waste product of breathing). To achieve this, the respiratory system requires a gas-exchanging organ (alveoli in the lungs), an effective pump to move the air (lungs, the breathing muscles – diaphragm) and effective control of the required depth and rate of breathing (the brain). When we breathe our respiratory muscles contract and the air that we inhale passes through our upper airways, nose, pharynx, larynx, trachea, bronchioles and onto our alveoli. It is when the air reaches the alveoli that the gas exchange takes place; the blood eliminates its carbon dioxide waste and replaces it with oxygen to feed the body cells.
There are two main reasons that may cause difficulties in breathing:
Obstruction: this is where the carbon dioxide stays within the alveoli. It causes breathlessness and frequent coughing to help clear secretions.
Muscle weakness: in this case you are not able to contract your muscles to allow air to enter the lungs and provide oxygenation.
Main symptoms of respiratory failure
People with respiratory failure may develop symptoms due to their reduced oxygen and increased carbon dioxide levels. These effects may include:
- Restlessness, confusion, agitation and breathlessness caused by a lack of oxygen
- Headaches, drowsiness and confusion caused by a buildup of carbon dioxide
Respiratory failure can be acute (developing rapidly) or chronic (developing slowly).
Respiratory failure is usually confirmed when you are in hospital by taking/performing an ‘arterial blood gas sample’. This sample of blood is taken from an artery rather than from a vein and is usually obtained from the wrist. This provides accurate information about how well the respiratory system exchanges oxygen and carbon dioxide. If a more comprehensive assessment is required, you may also be required to undertake an overnight sleep study and further lung function investigations.
Your consultant is the best person to speak to and advise you on your specific medical condition.