LECTURE ACTIVITY: RESPIRATORY SYSTEM
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)
1. Initiation of exercise
The neural changes that transmit excitatory impulses to the dorsal respiratory group (DRG) of the medullary respiratory center in the medulla cause an abrupt increase in breathing.
2. Moderate exercise
There is a gradual increase in breathing due to chemical and physical changes in the bloodstream. These chemical and physical changes include a slight decrease in PO2, a slight increase in PCO2, and an increased temperature.
3. Asthma attack
The lungs' internal airway walls swell and become inflamed during an asthma attack, which causes the airways to constrict or narrow. As a result, breathing becomes more difficult, which in some cases may lead to coughing and wheezing.
4. Abrupt ascent into high altitudes
Our breathing increases at high altitudes because there is a low amount of oxygen in the air, which sometimes causes us to feel ill. As a result, we tend to breathe more rapidly and deeply to boost the amount of oxygen that can enter the blood from the lungs.
5. Pneumonia
The infection causes the alveoli of the lungs to become inflamed as they get filled up with fluid or pus. As a consequence, it disrupts the regular gas exchange, making it difficult for oxygen to enter the bloodstream.
6. Paralysis of phrenic nerves
The paralysis of the phrenic nerves impedes the proper functioning of the diaphragm, which reduces the individual’s breathing capabilities and voluntary control over breathing. Moreover, this might also cause difficulty in maintaining adequate gas exchange since the lungs are not able to inhale O2 and exhale CO2 as efficiently.
7. Severe tuberculosis with resulting lung scar tissue
Severe tuberculosis is caused by the buildup of fluid between the respiratory membranes, or pleura, which causes the individual to exhibit chest pain and severe coughing. The scarring of the lung tissue (fibrosis) makes the person’s breathing more difficult, often resulting in shortness of breath.
8. Severe anemia
Because there are fewer RBCs carrying oxygen when anemia is severe, the body's capacity for gas exchange is compromised. As a result of the body's ongoing efforts to return oxygen levels to normal, a person with severe anemia may frequently experience shortness of breath and hyperventilation.
9. advanced COPD (chronic obstructive pulmonary disease)
With COPD, the lungs’ airways become inflamed and thickened, and the tissue where oxygen is exchanged is destroyed. Thus, it makes the patient unable to sustain a regular respiratory exchange and less able to adequately exhale CO2, which can lead to hypercapnia.
10. Advanced Pregnancy
The breathing muscle, the diaphragm, moves up and toward the chest during pregnancy. As a result, increased oxygen use and a reduction in the amount of air the lungs can hold contribute to the shortness of breath that many pregnant women experience.