Oxygen transport by the blood O2 in physical solution O2 in physical solution The O2 in physical solution determines the PO2 in the blood and therefore the direction of diffusion of O2. O2 carried by hemoglobin O2 carried by hemoglobin

The O2 content The O2 content 1- Amount of hemoglobin present. 2- O2 tension. 3- O2 affinity of hemoglobin. 4- Metabolic state of the organ The O2 capacity of blood The O2 capacity of blood hemoglobin saturation hemoglobin saturation Coefficient of O2 utilization Coefficient of O2 utilization

Carbon Dioxide Transport by the Blood Physically dissolved, 6% In chemical combination: As bicarbonate. 88% As bicarbonate. 88% CO 2 +H 2 O H 2 CO 3 H + + HCO3 - In combination with the amine group of blood proteins as carbamino compounds. In combination with the amine group of blood proteins as carbamino compounds. Hb-NH 2 +CO 2 Hb-NHCOOH 4% Protein-NH 2 +CO 2 ptn-NHCOOH 2% CA

CO2 H2O HCO3 Cl Na O2 + HCO3 Cl K H Hb O2 HHb O2Hb HHbCO2 RBCs Plasma Tissue fluid CA Carbamino reaction

Functions of intrapleural pressure Functions of intrapleural pressure Pneumothorax Pneumothorax Causes of recoil tendency of the lungs Causes of recoil tendency of the lungs elastic tissues 1/3 elastic tissues 1/3 surface tension 2/3 surface tension 2/3 Nature functions deficiency

How to measure How to measure spirometry spirometry helium dilution helium dilution Factors affecting the vital capacity Factors affecting the vital capacity Physiological / pathological Clinical significance of the vital capacity Clinical significance of the vital capacity Chest cage: bone/ muscle Lung: obstructive / restrictive abdomen Timed vital capacity Timed vital capacity FEV1/FVC%. FEV1/FVC%.