Parts of the Respiratory System - Overview

Henry’s law

 Henry’s law describes the behavior of gases when they come into contact with a liquid, such as blood.

 There are two types of sleep apnea: obstructive sleep apnea and central sleep apnea. 

Obstructive sleep apnea is caused by an obstruction of the airway during sleep, which can occur at different points in the airway, depending on the underlying cause of the obstruction. 

For example, the tongue and throat muscles of some individuals with obstructive sleep apnea may relax excessively, causing the muscles to push into the airway. Another example is obesity, which is a known risk factor for sleep apnea, as excess adipose tissue in the neck region can push the soft tissues towards the lumen of the airway, causing the trachea to narrow.

inspiration

 inspiration: the diaphragm and the external intercostal muscles. Additional muscles can be used if a bigger breath is required.

 This increase in volume leads to a decrease in intra-alveolar pressure,

expiration- When the diaphragm contracts, it moves inferiorly toward the abdominal cavity, creating a larger thoracic cavity and more space for the lungs. 

inspiration- Contraction of the external intercostal muscles moves the ribs upward and outward, causing the rib cage to expand, which increases the volume of the thoracic cavity.

This increase in volume leads to a decrease in intra-alveolar pressure, creating a pressure lower than atmospheric pressure. As a result, a pressure gradient is created that drives air into the lungs.

The process of normal expiration is passive, meaning that energy is not required to push air out of the lungs.

Instead, the elasticity of the lung tissue causes the lung to recoil, as the diaphragm and intercostal muscles relax following inspiration.

A deep breath, called diaphragmatic breathing, requires the diaphragm to contract. As the diaphragm relaxes, air passively leaves the lungs.

A shallow breath, called costal breathing, requires contraction of the intercostal muscles. As the intercostal muscles relax, air passively leaves the lungs.

There are four major types of respiratory volumes: tidal, residual, inspiratory reserve, and expiratory reserve.

Tidal volume (TV) is the amount of air that normally enters the lungs during quiet breathing, which is about 500 milliliters.

Expiratory reserve volume (ERV) is the amount of air you can forcefully exhale past a normal tidal expiration, up to 1200 milliliters for males.

Residual volume (RV) is the air left in the lungs if you exhale as much air as possible. 

The residual volume makes breathing easier by preventing the alveoli from collapsing. Respiratory

The residual volume makes breathing easier by preventing the alveoli from collapsing.

Inspiratory reserve volume (IRV) is produced by a deep inhalation, past a tidal inspiration.

Aortic body Monitors blood PCO2, PO2, and pH

Carotid body Monitors blood PCO2, PO2, and pH

Boyle’s Law

 At a constant temperature, changing the volume occupied by the gas changes the pressure, as does changing the number of gas molecules. Boyle’s law describes the relationship between volume and pressure in a gas at a constant temperature.

What Happens During an Asthma Attack?

 

inspiration: the diaphragm and the external intercostal muscles. 

Contraction and relaxation of the diaphragm and intercostals muscles (found between the ribs) cause most of the pressure changes that result in inspiration and expiration. 

Air flows into the lungs largely due to a difference in pressure; atmospheric pressure is greater than intra-alveolar pressure, and intra-alveolar pressure is greater than intrapleural pressure.

Air flows out of the lungs during expiration based on the same principle; pressure within the lungs becomes greater than the atmospheric pressure.

The process of normal expiration is passive, meaning that energy is not required to push air out of the lungs.