The act of breathing (respiration) should not be uncomfortable or painful. At times we all feel some breathing discomfort with indigestion or upper body muscular pain after a strenuous workout. In these cases, soreness or even pain when breathing is not considered to be a problem and often resolves without any treatment. However, painful breathing that persists and hampers the normal rate and rhythm of respiration should be investigated further as it may be a symptom of various diseases.
Normal Breathing Sensation
Most of us never give the act of breathing a second thought. The expansion and contraction of the chest wall and lungs, as well as movement of air may be palpable but it is neither uncomfortable nor painful. In fact, we would describe the sensation as being normal, or without pain or discomfort, although there is no specific term to describe it. Every minute we inhale and exhale anywhere between 12 to 20 times and this respiration rate varies by age and level of physical activity.
Flow of Air
Air enters through the nose or mouth, travels down the throat (pharynx), past the voice box (larynx), into the trachea and then is split down two bronchi to each lung. In the lungs, oxygen from the air is absorbed and carbon dioxide from the bloodstream is then passed out. The air then travels back out through the way it came. In order for this to happen, the respiratory muscles have to expand and contract the chest cavity around the lungs. It is important to understand how air flows through the airways and lungs, as well as the structures involved in this process to have a better understanding of where pain may be arising.
The main respiratory muscle is the diaphragm which is a large muscle sheet that sits below the lungs. The intercostal muscles between the ribs are the other important respiratory muscles. The diaphragm also separates the chest cavity from the abdominal cavity. When it contracts, it flattens and the negative pressure around the lungs causes it to expand. In fact the entire chest wall an expand to some extent. The lung tissue is highly elastic to inflate in this way. When the diaphragm relaxes, the lungs recoil and air is pushed out. Sometimes accessory muscles of respiration on the chest wall and neck also aid with inspiration and expiration.
Causes of Painful Breathing
Painful breathing largely implies that the pain is occurring in or around the chest or where the air passages are located. Sometimes the pain can be elsewhere in the body yet triggered or exacerbated during breathing. Most causes of pain during breathing arises from the airways, lungs, other organs of the chest cavity of chest wall. Sometimes it may be a problem in the abdominal cavity since the abdominal organs are also affected by the pressure changes during respiration.
Any injury to the chest wall, airways or lungs may cause painful breathing. A blow to the chest, soreness of the muscles and sometimes even very tight clothing are common causes of chest wall injury. These injuries can also lead to broken bones like a fractured rib which causes intense pain. Trauma may also extend to the tissue of the airways and lungs. This may be seen when inhaling smoke or air laden with noxious chemicals and particles. Usually the cause of the trauma can be identified.
Penetrating injuries may not always cause a gaping opening on the chest wall yet pain can be present. In a pneumothorax, air enters around the lungs. It can occur from within by mechanical ventilation or certain lung disease, or from the outside with chest wall injuries. Sometimes it occurs during certain medical procedures which is often unintentional. Other surgical procedures may also cause trauma to the chest cavity or lungs leading to pain when breathing. Sometimes symptoms like painful breathing occurs weeks after surgery for no clearly identifiable reason, like in post-commissurotomy syndrome.
Infections are also among the more common causes of painful breathing. Bronchitis, pneumonia, pleuritis, tuberculosis (pulmonary TB), psittacosis and other viral, bacterial and fungal lung diseases often present with pain when breathing. The pain may also be present with infections of the other parts of the airway like pharyngitis (sore throat), laryngitis (voice box infection) and tracheitis (windpipe infection) but pain in these conditions is not as common as it is with lung infections.
Sometimes chest wall infections, like in shingles, can also cause painful breathing. Common viral infections that affect the respiratory tract, like the common cold and influenza, can also cause pain with breathing but here as well it is not a frequently seen symptom unless bronchitis or pneumonia arise. An infection of the lining of the lungs (pleuritis) or heart (pericarditis) can also lead to painful breathing, most notably chest pain with deep breathing or specifically with inhalation.
Fractured bones mainly occurs with trauma. It is a significant cause of painful breathing. The pain is usually present at all times, but breathing exacerbates it. Fractures in one or more of the following three bones are more likely lead to pain with breathing includes ribs, sternum (breastbone) and/or the scapula (shoulder bone). However, even fractures of the vertebrae (spine bones), clavicle (collarbone) and sometimes even the pelvic bone can also present with pain when breathing.
A flail chest is where a portion of the ribcage breaks away from the rest of the chest wall. It is more likely to occur from motor vehicle collisions. Some bone and joint conditions may cause painful breathing despite there not being a fracture. Costochondritis or Tietze’s syndrome is where there is inflammation at the joint between the ribs and sternum. It is often mistaken for a sternal or rib fracture at times but is more of a cartilage and joint problem.
A number of other conditions can also painful breathing. Some may be relatively common, others less so. However, the most common have been discussed above.
- Abscess (lung or subphrenic)
- Aspiration pneumonia
- Decompression sickness
- Cancer (bronchogenic carcinoma, lung carcinoma, mesothelioma)
- Dressler syndrome
- Pulmonary embolism
- Hiatal hernia
- Tracheobronchial tear
- Esophageal tear
- Necrotizing granulomatous angiitis (lung)