BPK 305 Lecture Notes - Lecture 25: Hypocapnia, Bronchodilator, Trachea

• School: Simon Fraser University
• Department: Biomedical Physio & Kines
• Course: BPK 305
• Professor: Damon Poburko

Document Summary

Lecture 25 mechanical properties of the lungs ii. The respiratory cycle: during quiet breathing, *b -> as lungs stretch, ptp gets larger, *c -> a-b-c = inspire, c-d-a = expire, negative pressure = expanding, positive pressure = contracting. C = alveolar pressure changes: pa (alveolar) is variable, pb = 0 (barometric pressure, so p = pa, *pa = pip + ptp, when pip and ptp are equal and opposite = no change in alveoli size. D flow changes (i. e. ohm"s law) and pressure. = p / r -> (when r = raw: **v dot = flow of air, q = flow of blood. 3: abcf energy required to overcome resistance to airflow during expiration. If aabcf less than stored elastic energy (a0abcd), expiration can be passive. Pathology: a = normal, b = restrictive lung disease, changes compliance/stiffness of lungs, ex. pulmonary fibrosis, decreased compliance.