1. Initiation of exercise
- When exercise is initiated, there is an increase heart rate so that oxygen can be distributed throughout the body. The need for oxygen increases which will also lead to more production of carbon dioxide.
2. Moderate exercise
- When a person does moderate exercise, energy is expended by muscles. This in turn causes our body to increase its intake of oxygen, and our breathing will increase from 12L of air, around 15 times per minute.
3. Asthma attack
- During an asthma attack, the airway muscles constrict due to inflammation, which also results in mucus secretion, therefore narrowing the bronchial tubes. Air then becomes trapped in the lungs and the person experiences difficulty breathing.
4. Abrupt ascent into high altitudes
- When there is an abrupt ascent into high altitudes, there may be breathing instability and increased heart rate. This is due to the fact that there is a higher need to deliver oxygen throughout the body.
5. Pneumonia
- Pneumonia, which is an infection, causes a person to have difficulty breathing due to inflammation and fluids taking up the air sacs.
6. Paralysis of phrenic nerve
- Paralysis of the phrenic nerve, which aids in movement of the diaphragm, results to shortness of breath and sleeping difficulties.
7. Severe tuberculosis with resulting lung scar tissue
- With severe tuberculosis, the airways will narrow as a result of inflammation. Shortness and breath and chest pains could occur.
8. Severe anemia
- Due to low amounts of RBC, people with anemia experience shortness of breath and dizziness. This is due to the increase need to supply oxygen throughout the body.
9. Advanced COPD
- COPD obstructs the airways as they become swollen and inflammed. Breathing difficulties may result from this, such as difficulty breathing and increased breathing rate.
10. Advanced pregnancy
- As the uterus expands due to growth of the infant in the womb, it presses and pushes against other organs for space. This includes the lungs, which may result in pregnant mothers experiencing increased breathing rate and shortness of breath.