Chapter 5 RESPIRAION Introduction o Containing: inspiration expiration o Functions: Obtain o from external environment Remove co form the body o Respiratory processes: Pulmonary ventilation Gas exchange in the lung Gas transport in the blood Gas exchange in the tissue
Chapter 5 RESPIRATION Introduction • Containing: inspiration & expiration • Functions: Obtain O2 from external environment Remove CO2 form the body • Respiratory processes: Pulmonary ventilation Gas exchange in the lung Gas transport in the blood Gas exchange in the tissue
血液循环 组织、 肺 细胞 肺通气肺换气气体在血液组织细胞内氧 中的运输换气化代谢 Respirator 外呼吸 内呼吸 processes
Respiratory processes
8 1. Pulmonary ventilation ● Definition o Principles of pulmonary ventilation 米 Driving force Direct pressure changes in alveoli Source contraction of respiratory muscles Inspiratory muscles Diaphragm, External intercostal muscle Expiratory muscles: Diaphragm, Ext-& Internal intercostals Accessory respiratory muscles
§ 1. Pulmonary ventilation • Definition • Principles of pulmonary ventilation * Driving force Direct ~: pressure changes in alveoli Source ~: contraction of respiratory muscles Inspiratory muscles: Diaphragm, External intercostal muscle Expiratory muscles: Diaphragm, Ext- & Internal intercostals Accessory respiratory muscles
吸 呼气时 平静吸气时 深吸气时 Respiratory movement
Respiratory movement
ypes of respiration >Eupnea forced breathing deep breathing > Abdominal thoracic breathing Principles of pulmonary ventilation Contraction Relaxation) of inspiratory muscles->Expansion(Reduction) of thoracic cavity-(.)Distension (Recoil) of alveoli> Intrapulmonary pressure\(n<() atmo spheric pressure-Air flows into(out of) the alveoli
Types of respiration ➢Eupnea & Forced breathing (Deep breathing) ➢Abdominal & Thoracic breathing Principles of pulmonary ventilation ➢Contraction (Relaxation) of inspiratory muscles→Expansion (Reduction) of thoracic cavity→(?)Distension (Recoil) of alveoli→ Intrapulmonary pressure()) atmospheric pressure→Air flows into (out of) the alveoli
Intrapulmonary pressure >Inspiratory phase: Expiratory phase: >1 atm >At the end of inspiration or expiration:=l atm Intrapleural pressure More negative as inspiratory processing cle Concept changes during respiratory cy Less negative as expiratory processing >Measurement Expression Direct Indirect measurement 775 mmHg or-5 mmHg Always < I atm under static condition
Intrapulmonary pressure ➢Inspiratory phase: 1 atm ➢At the end of inspiration or expiration: =1 atm Intrapleural pressure ➢Concept & Changes during respiratory cycle More negative as inspiratory processing Less negative as expiratory processing ➢Measurement & Expression Direct & Indirect measurement 775 mmHg or −5 mmHg Always < 1 atm under static condition
吸气 呼气 肺内压 吸气 气 胸膜腔内压 A S 呼吸气容积0.6 0.2 时间(s) Changes of intrapulmonary intrapleural pressure tring respiratory cycle e
Changes of intrapulmonary & intrapleural pressure during respiratory cycle
>Formation iaP prf has opposite directions, so IPP=IAP-PRF At the end of insp-& expiration, so IPP=ASP-PRF If AsP=0. PP=0-PRF=-PRF IPP: intrapleural pressure IAP: intra alveolar pressure PRF: pulmonary recoil force ASP: atmospheric pressure
➢Formation IAP & PRF has opposite directions, so IPP=IAP−PRF At the end of insp- & expiration, so IPP=ASP−PRF If ASP=0, IPP=0−PRF= −PRF IPP: intrapleural pressure IAP: intra alveolar pressure PRF: pulmonary recoil force ASP: atmospheric pressure
Formation of intrapleural negative pressure
Formation of intrapleural negative pressure
>Significance Physiological Distend the lung make inspiration easier Promote venous lymph return in the chest Pathological (Pneumothorax Collapse the lung make inspiration difficult Affect venous lymph return Fatal in pulmonary circulatory failure cases Importance Keep the interpleural cavity hermetically sealed
➢Significance Physiological ~ Distend the lung & Make inspiration easier Promote venous & lymph return in the chest Pathological ~ (Pneumothorax) Collapse the lung & Make inspiration difficult Affect venous & lymph return Fatal in pulmonary & circulatory failure cases Importance Keep the interpleural cavity hermetically sealed
