KIN 275 Lecture Notes - Lecture 4: Alveolar Pressure, Blood Pressure, Pressure Gradient
14 Apr 2016
School
Department
Course
Professor
Document Summary
Fick"s law: diffusion constant of gas diffusing - solubility and molecular weight. At rest o2 diffusion capacity limited by incomplete lung perfusion: only bottom 1/3 going to be really well perfused because close to heart, top 2/3 lung surface. During exercise, o2 diffusion capacity increases due to more lung perfusion: even gas exchange. O2 diffusion capacity: o2 volume diffused per minute per 1 mmhg of gradient, bigger gradient, bigger diffusion. Max exercise, venous o2 drops, po2 bigger gradient: diffusion capacity increases. Middle 1/3: arterial pressure higher than alveolar pressure, higher than venous pressure, good ventilation, moderate perfusion. Lower 1/3 pa(lveolar)>pv>pa(rterial: alveolar pressure allows easy diffusion across other membranes. Oxygen: can carry 20 ml of o2/100ml blood. Carbon dioxide: released as waste from krebs, carried 3 ways. Bicarbonate ions: transports 60-70% of co2 in blood to lungs. Thursday, april 14, y: co2 and water form carbonic acid, carbonic acid dissociates into bicarbonate. Wings to hb and triggers bohr effect.
