BPK 142 Study Guide - Final Guide: Thoracic Cavity, Lung Volumes, Pneumothorax

• School: Simon Fraser University
• Department: Biomedical Physio & Kines
• Course: BPK 142
• Professor: Jim Carter

Document Summary

For every 10 meter of depth (33ft) the pressure increases by one atmosphere. The air cavities in our body compress under pressure which causes pain. The volume of gas varies inversely with the pressure on it. As the pressure of the gas increases, the volume decreases. The longer the tube we have to breathe through, the greater the dead space. If the tube is too long, there is no air reaching our alveoli. Scuba divers breathe in compressed air which helps overcome the pressure on their thoracic cavity. Snorkelers however, must breathe the air at atmospheric pressure even though there is still some pressure on their thoracic cavity. If compressed below residual volume, lung damage occurs because blood is sucked from pulmonary capillaries into the alveoli. Decreases the amount of co2 in our blood. When the diver is ascending, the pressure of oxygen in their lungs can decrease below the critical point and they can lose consciousness and drown.