Chronic Obstructive Pulmonary Disease (COPD) is a chronic lung disease that includes two main illnesses: chronic bronchitis and emphysema. There is no cure for COPD. If you have chronic bronchitis, the lining in your bronchial tubes gets red and full of mucus. This mucus blocks your tubes, and makes it hard to breathe. If you have emphysema, your alveoli are irritated. They get stiff and can't hold enough air. This makes it hard for you to get oxygen into and carbon dioxide out of your blood.
Spinal Muscular Atrophy (SMA) Children with type 1 have a weakness of the intercostal muscles (the muscles between the ribs) that help expand the chest, and the chest is often smaller than usual. The strongest breathing muscle in an SMA patient is the diaphragm. As a result, the patient appears to breath with their stomach muscles. The chest may appear concave (sunken in) due to the diaphragmatic (tummy) breathing. Also due to this type of breathing, the lungs may not fully develop, the cough is very weak, and it may be difficult to take deep enough breaths while sleeping to maintain normal oxygen and carbon dioxide levels. Children with Type II also have weak intercostals muscles and are diaphragmatic breathers. They have difficulty coughing and may have difficulty taking deep enough breaths while they sleep to maintain normal oxygen levels and carbon dioxide levels. Scoliosis is almost uniformly present as these children grow, resulting in need for spinal surgery or bracing at some point in their clinical course.
Duchennes muscular dystrophy (DMD) When the muscles involved in breathing become very weak, lung function becomes inadequate so that there is not enough oxygen and too much carbon dioxide in the blood. This causes drowsiness, headaches and a general lack of well-being. When this happens, assistance with breathing through a face mask, used during sleep, may return the blood oxygen and carbon dioxide levels to normal and relieve the symptoms. A small number of affected people choose to have mechanically assisted breathing for 24 hours a day when their breathing muscles are so weak that they could not otherwise support life
Guillain-BarreA disorder involving progressive muscle weakness or paralysis, usually after an infection – particularly a respiratory or gastrointestinal one. It is caused by inflammation of nerves and results in damage to the cover (myelin sheath) of the nerve. This damage causes the nerves to stop working effectively by slowing the messages carried to muscle and skin through the nerve. The symptoms of the disorder usually appear after the infection has gone and progress rapidly. These symptoms may include muscle weakness, paralysis, or spasms; numbness or tenderness; and blurred vision. Possible complications include: Persistent paralysis Respiratory failure, mechanical ventilation Hypotension or hypertension. Most patients require hospitalization and about 30% require ventilatory assistance.
Asthma If you have asthma, the inside walls of your airways are inflamed (swollen). The inflammation makes the airways very sensitive, and they tend to react strongly to things that you are allergic to or find irritating. When the airways react, they get narrower, and less air flows through to your lung tissue. This causes symptoms like wheezing (a whistling sound when you breathe), coughing, chest tightness, and trouble breathing. During an asthma attack, muscles around the airways tighten up, making the airways narrower so less air flows through. Inflammation increases, and the airways become more swollen and even narrower. Cells in the airways may also make more mucus than usual. This extra mucus also narrows the airways. These changes make it harder to breathe.
Cystic Fibrosis (CF) In a healthy person, there is a constant flow of mucus over the surfaces of the air passages in the lungs. This removes debris and bacteria. In someone with CF, this mucus is excessively sticky and cannot perform this role properly. In fact, the sticky mucus provides an ideal environment for bacterial growth. People with CF are at risk of bacterial chest infections. About half of people with CF have repeated chest infections and pneumonia. If they are not treated early and properly, these are very difficult to treat. Symptoms include persistent coughing, excess production of sputum (saliva and mucus), wheezing, and shortness of breath with ordinary activities People with CF need daily chest physiotherapy, which involves vigorous massage to help loosen the sticky mucus. Parents of a child with CF are taught by hospital staff how to do this. Older children and adults with CF can be taught to do this for themselves. Chest physiotherapy is important because helps to prevent the thick, sticky lung secretions from blocking the air tubes. This helps to reduce infection and prevent lung damage. The length of treatment sessions varies according to need. If there are few or no secretions, treatment sessions may only need to last 10-15 minutes. However, it could take as long as 45-60 minutes if there are many secretions to be cleared. The number of treatment sessions should be varied. Most people do two a day when all is well, increasing to four a day when necessary. If no secretions are present, some people with CF only need treatment once a day.
Chronic respiratory failure (CRF) is associated with nocturnal hypoventilation. Due to the interaction of sleep and breathing, sleep quality is reduced during nocturnal hypoventilation. Non-invasive mechanical ventilation (NMV), usually performed overnight, relieves symptoms of hypoventilation and improves daytime parespiratory status in patients with CRF. This type of ventilatory support is now used commonly to assist ventilation in patients with a variety of neuromuscular and chest wall diseases. These may be separated into spinal cord lesions, diseases of peripheral nerves, disorders of the neuromuscular junction, diseases of muscles, and chest wall disorders.
The incidence of respiratory muscle dysfunction varies among these different entities. In neuromuscular disease, the degree of compromise may differ significantly between respiratory and nonrespiratory muscles, and not all respiratory muscles may be similarly impaired. The clinical course also varies, as respiratory muscle weakness may be:
Completely reversible (Guillain-Barre syndrome)
- Reversible with treatment (myasthenia gravis)
- Relapsing (multiple sclerosis)
- Relentlessly progressive (amyotrophic lateral sclerosis)
In several of these disease processes, respiratory function may also be compromised by parenchyma lung disease (polymyositis) or abnormal control of breathing. Nevertheless, despite the diversity of these underlying conditions, the resulting critical illness and the respiratory consequences of severe disease tend to be similar.
