Briefly explain the main cause or mechanism of the increase in respiratory rate or depth and/or respiratory difficulties in the following cases: (one to two sentences only)
Initiation of exercise
- During the onset of an exercise, the brain detects a slight increase in the body's carbon dioxide level and in turn, demands a higher respiration rate to eliminate it and supply oxygen to the cells. This is controlled by the respiratory center within the medulla oblongata, which responds to the changes in the oxygen and carbon dioxide in the blood.
Moderate exercise
- The demand for gas exchange in the lungs rises due to increased oxygen consumption and carbon dioxide production, which is a result of meeting the needs of the contracting muscles during moderate exercise.
Asthma attack
- When a person experiences an asthma attack, the airways become swollen and inflamed. The bronchial tubes become narrow due to the contraction and production of extra mucus in the airways, which causes trouble breathing and in some cases, hyperventilating.
Abrupt ascent into high altitudes
- Air pressure is lower at higher altitudes, which means the body takes in less oxygen. Thus, during an abrupt ascent into the sky, a person often feels drained or short of breath.
Pneumonia
- Pneumonia is a form of acute respiratory infection wherein the alveoli become inflamed and filled up with fluid or pus, which makes it difficult to breathe in oxygen and for it to enter the bloodstream.
Paralysis of phrenic nerve
- When the phrenic nerve is damaged, the diaphragm can become weak and paralyzed. This may cause difficulty in maintaining adequate gas exchange, reduced breathing capabilities, and inability to control voluntary breathing.
Severe tuberculosis with resulting lung scar tissue
- Tuberculosis is a bacterial infection that results in airway inflammation. With scarred lung tissues, difficulty getting oxygen to the rest of the body is all the more expected, which may also cause high blood pressure in the lungs.
Severe anemia
- A patient with severe anemia is not supplied with enough oxygen-rich blood, which may lead to hyperventilation and a rapid heartbeat as a result of the body's constant effort to restore oxygen levels. Because of this, the patient is likely to feel tired, weak, and short of breath.
Advanced COPD (chronic obstructive pulmonary disease)
- With an inflammatory lung disease such as COPD, the airflow in the lungs is obstructed, which makes breathing difficult. When this advances, the body becomes more vulnerable to breathing complications, lung infections, or respiratory failure.
Advanced pregnancy
- During the later stage of pregnancy, the uterus begins to press on the diaphragm, which makes it difficult for the lungs to expand. This may result in shallow breathing and the feeling of short breath.