Chapter 5 RESPIRATION Introduction Containing:inspiration expiration ●Functions: Obtain O,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
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、 细胞 00 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 Respiratory 外呼吸 内呼吸 processes
Respiratory processes
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
§ 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
平静吸气时 深吸气时 Respiratory movement
Respiratory movement
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）训of alveoli--→ Intrapulmonary pressure(T))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:=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
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 1呼气 肺内压 胸膜腔内压 气容积 。 容积 1234 时间(s) Changes of intrapulmonary intrapleural pressure during respiratory cycle
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,IPP=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