KIN 3304 1nd EditionExam #4 Study Guide Lectures: 22 - 33Lecture 22 (October 19) The Respiratory System is divided into the upper respiratory system and the lower respiratory system. - The Upper Respiratory Tract o Nose, nasal cavity, paranasal sinuses, pharynxo Warms and moistens the air  You always humidify airo Protects the delicate LRS Well-developed lymphoid barrier Superficial mucus barrier- The Lower Respiratory Tracto Larynx, trachea, bronchi, and lungso Gas exchange occurs hereo Larynx Closed during swallowingo Lumen of trachea Held open by incomplete, C-shaped cartilaginous rings Helps to keep airway openo Trachea bifurcates (splits) into main bronchi Then forms the bronchial treeAirway Generations- The number of airway generations to reach the respiratory zone- Airways get smaller but double in numberPossible TQ’s:- CO2 is just as important in the breathing process- Passive Breathing – uses just the diaphragm (which is the major respiratory muscle)- Active Breathing – uses more muscles- Be familiar with muscles of inspiration and expiration- You don’t have lung muscles, you have respiratory muscles- Be familiar with the Respiratory Mechanics PicturePhysiology of Respiration- All processes involve the uptake of O2 and the release of CO2- 3 Basic Processeso Mechanics of lung and thoraxo Gas Exchange (atmosphere to alveoli)o Transport of gases in the blood Structure of Thorax- Thorax provides structure and protection for lungs- Allows for lung volume changeso The larger the individual, usually the larger the lungso Due to articulation of the ribs and diaphragm motion- Lots of musclesPleural Space- Lungs are covered by thin visceral pleura and it normally contains a few mL of lubricatingfluid- Inspiratory force of chest wall/diaphragm is transmitted to the lung by negative pressure- Penetration/rupture of the lung surface can happen hereo Pneumothorax An abnormal collection of air or gas in the pleural space Common in tall slender meno Air can enter the thoracic cavityGas Exchange - Occurs in the alveoli when fresh inspired air comes in contact with capillary bloodo Alveoli is what expands and contracts and they fill up with air- Must pass through conductive airwayso Some air remains in the CA (means there is no exchange)o CA are termed “anatomical dead space” because its using air to push air- Respiratory bronchioles, alveolar ducts, sacs, and alveoli- Occurs where basal laminae of alveolar epithelium and capillaries have fused- Rapid diffusion due to:o Sizeo Gases are lipid solubleAlveolar Cells can be either Type 1 or Type 2- Type 1o Creates air sacs- Type 2o Secretes surfactant that’s a combination of a phospholipido Absorbs Na+, H2Oo Lowers surface tension o Keeps alveoli from collapsingo Has a structural interdependence Local distortion opposed by surrounding tissue If a small zone of alveoli collapses, surrounding tissue stretches, pulls zone back open Termed “structural interdependence” Along with surfactant, collateral air pathways help prevent collapse of alveoli (called atelectasis)o Scattered among squamous cells Also have alveolar macrophages - phagocytosisLecture 23 (October 31)Pulmonary Physiology in Pregnancy- Tidal Volume increases o b/c she’s breathing for two- Residual Volume decreaseso b/c the uterus is pressing up on the diaphragm- Total Lung Capacity decreaseso b/c the uterus is pressing up on the diaphragm- Expiratory Reserve Volume decreaseo b/c the uterus is pressing up on the diaphragmPartial Pressure- Sea level – PP ambient air = 760 mmHg- Usually measured”dryo Water vapor is removed when comparingo Allows for universal comparisons- 760 (ambient air) – 47 (water vapor, in trachea) = 713 mmHgO2 Transport- Hemoglobin (Hb)o One mole carries 4 moles of O2- Decrease in pH, increase in PCO2 and temperature:o Helps to unload O2 at the tissues o Ex. exerciseNormal Arterial O2 ContentFick’s Equation- VO2 = Q x (a – VO2 difference)o VO2 – O2 consumptiono Q – cardiac outputo CaO2-CvO2 – difference between alveolar and mixed venous O2 contento CaO2 – arterial O2 contento CvO2 – mixed venous O2 contento PVO2 – mixed venous PP of O2Lecture 24 (November 3)Gas Diffusion- Simply from high to low (concentration)o In lungs, between alveolar gas and capillary blood- We call this the diffusion capacity (DL)o Total DL of lung made up of: Diffusion process through alveolar membrane Resistance of RBC + chemical combination with Hb- RBC’s spread every .75 seconds in alveolar capillarieso This is called the “capillary transit time”- With normal DLo .25 seconds – enough O2 crosses the membrane to bring Hb to equilibrium with alveolar PO2- With severely limited DL (<. 25)o There will be diffusion abnormalityo Low O2 saturation at rest (disease)Lecture 25 (November 5)Things to know:- As soon as you go unconscious, breathing resets- Left lung is where the cardiac notch- Hb will drop O2 to pick up CO- Known what a collapsed lung looks like- Incubator is similar in relation to the lower respiratory tract because a lot of stuff can growthere- Iron lungFunctions of the Respiratory System- We will only be focusing on 2:o Gas Exchangeo Move air to/from Lung SurfacePrimary Bronchi - The trachea branches into the right and left primary (main) bronchio Extrapulmonary bronchi are located outside the lungs- The main bronchi then travel to a groove (hilum) along the lungo This provides cross for pulmonary vessels and nerveso Anchored with dense CT (the rest of the lung)Bronchioles- Tertiary bronchus branches many times- ANS regulates activity and controls diameter- Epithelium causes bronchodilation- Parasympathetic stimulation causes bronchoconstriction Respiratory Bronchioles- Each terminal bronchiole delivers air to a single pulmonary lobule- Within a lobule, terminal bronchiole branches into respiratory bronchioleso These deliver air to lung (surface exchange)o No mucus cells/glands hereAlveolar Ducts and Alveoli- Respiratory bronchioles are connected to independent and multiple alveoli along alveolar ductso They end at alveolar sacso Why the lung is “spongy” in appearance- There is a huge capillary network association with each alveoluso Surrounded by Elastic Fiber (expansion) Elastic Fibers are well developed Found at every level of respiratory system When lungs expand, elastic recoil returns lungs to unexpanded volumeAlveolus and Respiratory Membrane- Alveolar