3 most important structures of the respiratory system:
- Lungs: o2 and co2 out
- Muscles of respirations:breathing is a passive process from high to low.
- Brain:Sympathethics increases respiratory rate,
- Para: decrease
The upper airway that are aligned with ciliated mucosa to keep foreign particles out.
The structure that connects upper to lower airways:
Larynx: voice box
- 2.immune support-debris,mucins(proteoglycans),bacteria interface
- 3.lubricant-to allow food move into digestive tract
- 90%apirations go into the right lung
Protect the larynx voice box
complete lung collapse
One lobe partial collapse
pomegranates only in alveoli, it deceases surface area for gas exchange, less oxygen in the blood, gas exchange problem.
Is an inflammation of the tissue lining,mucosa membranes
Mediastinum: self from non-self
intubation,connected to epiglottis
Mechanics of breathing:3
- accessory muscles
- elastic properties of the lungs and chest walls
- resistance air-flow through the conducting airways.
Muscles of inspiration:
Diaphram and intercostal muscles(between the ribs), causes negative pressure that draws gas into the lungs through the upper airways trachea, increase during excersie
abdominal and internal intercostal muscles
Surfactant lowers by coating the alveoli, lipoprotein produced by type 2 alveolar cells
Elastic properties: recoil
lungs to returning to its normal state after inspiration, depends on chest wall.
- Increased compliance indicates has lost some elastic recoil and abnormally easy to inflate:
- Decreased compliance: stiff or difficult to inflate.
airway increases when the diameter of the airway decreases. Bronchoconstriction, which increases airway resistance can be caused by parasympathetic receptors in the bronchial smooth muscle. or by edema or tumors
Work of breathing:
is determined by muscular effort, and oxygen required. More muscle effort is required when lung compliance decreases,
Mechanics of breathing:
- Ventilation:is the movement of air between the environment and the lungs
- Diffusion:of oxygen from the alveoli into the capillary blood , happens in the lungs
- Perfusion:the blood that reaches the capillaries
- Diffusion:from capillaries into tissue cells out of blood
Mechanics of breathing:Pons of the brainstem
- 1.Apneustic center-stimulates neurons to promote expiration and inspiration intercostal and diaphram.
- 2.Pneumotaxic center:stimulated neurons to promote expiration via the internal intercostals and rectus abdominis
Mechanics of breathing:
- 1.Chemoreceptors-central located in the medulla
- 2.PEripheral-located in the aorta and carotid bodies
- **Both detect increased levels in co2 and then stimulate increase in RR
- 1. mechanical movement-of gas or air into and out the lungs
- 2.minute volume - ventilator rate multiplied by the volume of air per breath
- 3.alveolar ventilation:the amount of air that reaches the alveoli and is available for gas exchange with the blood per unit time.
- Alveoli-epithelial cells
- -Type 1 alveolar cells, alveolar structure, where diffusion of respiratory gasses occur.
- -Type 2-surfactant production
- has a lower pressure than the systemic circulation.
- One-third of pulmonary vessels are filled with blood at any given time.
Alveolocapillary membrane formed by the shared alveolar and capillary walls
- -Gas-exchange occurs across this membrane
- -Membrane -Type 1
- oxygen transport-diffusion across the alveolocapillary membrane.
- -dissolved in plasma
- carbon dioxide
- dissolved in plasma
- bicarbonate-(Hco3)-90% of co2
- PA-alveoli pressure
- PIP-intrapleura pressure
- PB-atmosphere pressure
- Inhalation: PB>PA>PIP
- Exhalation: PA>PIP>PB
- low co2(high02)-vasodilation
- hco3=basehigh PH
- *high co2 massive vasoconstriction cause pulmonary hypetension