Respiratory Physiology u heart heart circuitry heart circuitry tissues lung heart circuitry tissues lung heart circuitry tissues cell STRUCTURE of respiratory system - Conducting zone - - Respiratory zone STRUCTURE of respiratory system - Conducting zone (nose, larynx, trachea, bronchi, bronchioles) The walls conducting airways contain smooth muscle -Sympathetic -Parasympathetic - -b2 receptors - relaxation, dilatation of the airway - STRUCTURE of respiratory system - Conducting zone - Anatomic dead space -V of the conducting airways - Physiologic dead space -V of the lungs that does not participapate in gas exchance STRUCTURE of respiratory system - Conducting zone - Physiologic dead space (VD) -V of the lungs that does not participapate in gas exchance PaCO2 – PECO2 VD = VT x ---------------- PaCO2 VT – tidal volume PaCO2 – PCO2 of arterial blood PECO2 – PCO2 of mixed expired air STRUCTURE of respiratory system Respiratory zone Alveoli Lung ~ 300 x 106 alveoli diaphragm inspiration expiration inspiration – mm. intercosales externi expiration – mm. intercosteles interni inspiration – mm. intercosales externi expiration – mm. intercosteles interni inspiration – mm. intercosales externi expiration – mm. intercosteles interni inspiration – mm. intercosales externi expiration – mm. intercosteles interni inspiration – mm. intercosales externi expiration – mm. intercosteles interni inspiration – mm. intercosales externi expiration – mm. intercosteles interni inspiration – mm. intercosales externi expiration – mm. intercosteles interni S02401-037-f001 diaphragm inspiration expiration pleura parietalis diaphragm inspiration expiration pleura visceralis diaphragm inspiration expiration pleura parietalis pleura visceralis transmural pressure diaphragm inspiration expiration pleura parietalis pleura visceralis transpulmonal pressure diaphragm inspiration expiration pleura parietalis pleura visceralis intrapulmonal pressure diaphragm inspiration expiration pleura parietalis pleura visceralis transmural pressure transpulmonal p. intrapulmonal pressure S02401-037-f002 diaphragm inspiration expiration pleura parietalis pleura visceralis transpulmonal p. bránice - diaphragma inspirace expirace pleura parietalis pleura visceralis transmural p. PNEUMOTHORAX diaphragm inspiration expiration pleura parietalis pleura visceralis transmural p. transpulmonal p. intrapulmonal pressure alveoli ventilation V Physiologic dead space Is the volume of air in the lungs that does not participate in gas exchance (i.e.e it is dead) Anatomic dead space – is the volume of conducting airways Functional dead space volume – which is made up of alveoli that do not participate in gas exchance (alveoli that are ventilated, but are not perfused by pulmonary capilary blood) Physiologic dead space PaCO2 – PECO2 V D = VT x ----------------------- PaCO2 VD – physiologic dead space (mL) VT – tidal volume (mL) PaCO2 – PCO2 of arterial blood (mmHg) PECO2 - PCO2 of expered air (mmHg) Physiologic dead space PaCO2 – PECO2 V D = VT x ----------------------- PaCO2 40 - 30 VD = 500 x -------------- 40 = 500 x 0.25 = 125 Alveolar ventilation VA = (VT – VD) x breasths/min VA - alveolar ventilation (mL/min) VT - tidal volume (mL) VD - physiologic dead space (mL/min) Alveolar ventilation VA = (VT – VD) x breasths/min VA = (500 – 125) x 16 = 375 x 16 = 6000 mL/min lung heart circuitry tissues cell diffusion perfusion S02401-039-f007 S02401-038-f006 S02401-039-f009 ventilation diffusion perfusion ventilation - static volums - dynamic volums S02401-037-f005 S02401-037-f006 STATIC VOLUMS 1 s FEV1 VC V t DYNAMIC VOLUMS FEV1 -------- x 100 VC > 80 % Physiological value: 1 s FEV1 VC V t DYNAMIC VOLUMS OBSTRUCTION ¯ FEV1 = VC Restriction ¯ VC = FEV1 respirace-a272.jpg respirace-a273.jpg Infection inhaled allergens inhaled irritants food allergens inducing stimuli mental stress medicines Triggers respirace-a274.jpg respiratory irritant factors physical activity preventing infection sick people, vaccination, intensive treatment sufficient fluid intake eat small portions breathing exercises respirace-a275.jpg Differential diagnosis respirace-a276.jpg steroid potentiation of beta-adrenergic receptor bronchospasmolytic effect cholinergic antagonism reduction in mucus production - anti-inflammatory effect - block the formation of antibodies - stabilization of lysosomes block - formation and release of histamine - 1 s FEV1 VC V t DYNAMIC VOLUMS RESTRICTION = FEV1 ¯ VC difusion alveolo-capillary membrane (surfactant) difusion alveolo-capillar membrane (surfactant) perfusion (heart) S02401-038-f006 srdce12036.jpg Pulmonary edema - cardiogenic - noncardiogenic srdce11035.jpg Cyanosis (right ventricle) Causes of cyanosis Central cyanosis Decreased arterial saturation Hemoglobin abnormalities Peripheral cyanosis Reduced cardiac output Cold exposure Redistribution of blood flow from extremities Arterial obstruction Venous obstruction lung heart circuitry tissues cell perfusion (anemia) perfusion (emboli) perfusion (emboli) 20% 20% dg. pulmonal emboli 20% 20% Dg. pulmonal emboli % hemoglobin saturation 100 pO2 Bohrs effects % hemoglobin saturation 100 Bohrs effect – O2 hemoglobin dissociation curve 0 25 50 75 100 pO2 % hemoglobin saturation 100 Shift to the right 0 25 50 75 100 pO2 100 čas Shift to the right temperature ¯ pH [H+] 2,3 - DPG % hemoglobin saturation 0 25 50 75 100 pO2 100 Shift to the left ¯ temperature pH ¯ [H+] ¯ 2,3 - DPG % hemoglobin saturation 0 25 50 75 100 pO2 % hemoglobin saturation 100 Bohr effect 0 25 50 75 100 pO2 pO2 mmHg saturation (%) 10 25 20 35 25 50 30 60 40 75 50 85 60 90 80 96 100 98 Values of pO2 and corresponding values of percent saturation of hemoglobin S02401-040-f001 S02401-040-f003 S02401-040-f013 S02401-020-f006 lung heart circuitry tissues cell