A. ACTIVITY
Briefly explain the main cause or mechanism of increase in respiratory rate or depth and/or respiratory difficulties in the following cases: (one to two sentences only)
1. Initiation of exercise
Respiratory rate increases at the onset of exercise because of neural changes that send excitatory impulses to the medullary respiratory center's Dorsal Respiratory Group (DRG); causing stimulation of the limbic system, sensory impulses from proprioceptors in muscles, tendons, and joints, and motor impulses from the primary motor cortex.
2. Moderate exercise
The increase in the respiratory rate in moderate exercise occurs due to the chemical and physical changes in the bloodstream such as a slightly decreased partial pressure of Oxygen, a slightly increased partial pressure of Carbon Dioxide, and an increased temperature.
3. Asthma attack
Asthma attacks are characterized by difficulty breathing, coughing, wheezing, and chest tightness. This is usually caused by airway inflammation, and/or obstruction because of smooth muscle spasms in the walls of smaller bronchi and bronchioles, edema of the mucosa of the airways, increased mucus secretion, and/or damage to the epithelium of the airway.
4. Abrupt ascent into high altitudes
Hypoxic hypoxia causes difficulty in breathing because of low partial pressure of oxygen in arterial blood due to abrupt ascents or high altitudes.
5. Pneumonia
Rapid or difficulty breathing in pneumonia is caused by an acute infection or inflammation of the alveoli as a result, toxins and immune response damage the alveoli and bronchial mucous membranes; interfering with ventilation.
6. Paralysis of phrenic nerve
The phrenic nerve innervates the diaphragm, and thus paralysis of the phrenic nerve may cause dyspnea or shortness of breath.
7. Severe tuberculosis with resulting lung scar tissue
Tuberculosis is a communicable disease from the bacterium Mycobacterium tuberculosis that usually affects the lungs and pleurae. As a result, it causes inflammation and also dyspnea.
8. Severe anemia
The main cause of difficulty breathing in severe anemia is anemic hypoxia, which happens when there is too little functioning hemoglobin present in the blood, thus decreasing oxygen transport to tissue cells.
9. advanced COPD (chronic obstructive pulmonary disease)
Advanced COPD causes difficulty in breathing by permanent damage to the airways and therefore causing airflow obstruction. This usually results from cigarette smoking, secondhand smoke, air pollution, pulmonary, infection, occupational exposure to dust and gases, and other genetic factors.
10. Advanced pregnancy
In order to meet the oxygen demands of the fetus, respiratory function in pregnancy is altered, causing an increase in minute ventilation. The uterus also starts to press on the diaphragm, preventing full expansion of the lungs, and causing shortness of breath.