NURS 471 Lecture Notes - Lecture 8: Heart Sounds, Mental Status Examination, Mucus
Document Summary
Stages of respiration: external respiration/ventilation, movement of air in the lungs occurring bc change in the intrathoracic pressure in lungs related to pressure in airways. Gas goes from high pressure to low pressure. O2 goes into the body and is expelled to get rid of co2. O2 goes into the blood and co2 goes into the lungs. Both voluntary and involuntary, using intercostal muscles and diaphragm. Contraction of intercostal muscles increases chest dimension, decreasing intrathoracic pressure, causing gas to go from high pressure (atmospheric) to lower pressure (intrathoracic): diffusion, movement of materials from higher to lower concentration. Alveoli: where o2 diffuses into the blood. Co2 diffuses from blood into alveoli and is exhaled. Tissues: o2 diffuses from blood into the cells. Co2 diffuses from cells into the: transport blood, o2 and co2 move abck and forth across capillary membrane by diffusion. O2 moves from alveolar gas into the arterial blood. Co2 moves from arterial blood into the alveolar gas.
