N3 Anatomy and Physiology (1st Sem AY 2022-2023)

Initiation of Exercise: Once exercise begins, the respiratory frequency increases rapidly. The breathing rate increases so that more oxygen can be brought to the lungs and pumped into the bloodstream. 

Moderate Exercise: During moderate exercise, the body utilizes more oxygen and releases more carbon dioxide as the muscles work harder. Because of that, the rate and depth of breathing increase, ensuring that more oxygen is absorbed and more carbon dioxide is liberated. 

Asthma Attack: During an asthma attack, the muscles of the airways contract, and the lining inside becomes inflamed and swollen and gets congested with large amounts of mucus. As a result, the airways become narrower, thus breathing becomes harder in this case.

Abrupt Ascent into High Altitudes: At high altitudes, the atmospheric pressure decreases, and consequently there is a lowering of oxygen pressure. So, to compensate for that and obtain an adequate supply of oxygen, an individual’s breathing rate increases.

Pneumonia: Pneumonia is an infection that causes the air sacs to become inflamed and filled with fluid or pus. This makes it harder for a person to breathe, which leads to an increase in respiratory rate. 

Paralysis of Phrenic Nerve: The phrenic nerve is the only nerve that provides signals to the diaphragm for it to contract and expand, allowing the lungs to inhale and exhale air. So, when the phrenic nerve is paralyzed, the diaphragm is also affected and disabled, which makes it more difficult for someone having this condition to breathe on their own.

Severe Tuberculosis with Resulting Lung Scar Tissue: Tuberculosis is an infection caused by bacteria that destructs the tissue in the lungs and inflames the airways. This provides difficulties for a person to breathe as it affects the passage of air into the blood given the scarring of the lung tissue. 

Severe Anemia: With anemia, the body cannot produce an adequate amount of red blood cells that carry oxygen because of the lack of iron. So, in an effort to restore the body’s oxygen level to normal, the lungs overcompensate and bring in more oxygen, which leads to rapid breathing. 

Advanced COPD (Chronic Obstructive Pulmonary Disease): With COPD, the airways become inflamed and tissue (where oxygen is exchanged) is destroyed, decreasing the flow of air in and out of the lungs. So, when COPD becomes very severe, a person experiences critical shortness of breath, even when at rest. 

Advanced Pregnancy: Because of the increase in the hormone progesterone, a pregnant woman may feel as if she needs to breathe in more deeply. In addition, she may also experience difficulties in breathing due to the enlarging uterus that takes up more space and is pressuring against the diaphragm.