Presentation Transcript

1. Internal & External Respiration Events #2 & 4 Gas Exchanges in the Body
2. Dalton’s Law Used to determine the individual pressures of each gas in a mixture of gases Based on % of total of 760 mmHg of total atmospheric pressure
3. Dalton’s Law Gas exchanges that occur: Between the blood and the alveoli AND Between the blood and the tissue cells Take place by simple diffusion Depends on partial pressures of oxygen & carbon dioxide that exist on opposite sides of the exchange membrane (Dalton’s law of partial pressures) Always flowing from high to low
4. Henry’s Law states thatthe solubility of a gas in a liquid is directly proportional to the pressure of that gas above the surface of the solution (IOW: the higher the pressure of the gas, the more gas will be shoved into the liquid thus increasing solubility)
5. Henry’s law Solubility (of a gas) and partial pressure have a direct relationship
6. Solubility Coefficients The solubility coefficient of the gas also affects this process – the higher the #, the more the gas “likes” to dissolve into a liquid (based on molecular structure, etc.) Each gas will dissolve in a liquid in proportion to the ratio between its partial pressure gradient and its solubility coefficient CO2 = .57 O2 = .024 N2 = .012
7. 2nd Law of Thermodynamics Solubility & temperature have an inverse relationship. Increase in temperature causes increase in kinetic energy causes more molecular motion which allows molecules to break the intermolecular bonds and escape from solution And vice versa
8. 2nd Law of Thermodynamics
9. Factors that Influence:Ratio Relationships Partial pressure gradients and gas solubilities Oxygen = has low solubility but steep partial pressure gradient (105 mmHg in alveoli – 40 mmHg in blood = 65 mmHg pressure gradient) Carbon dioxide = has solubility ~20x greater than oxygen but partial pressure gradient is only 5 mmHg
10. Partial pressure gradients and gas solubilities Due to the ratios of solubility coefficients and pressure gradients: ~Equal amounts of gases are exchanged Factors influencing internal & external respiration
11. Factors influencing internal & external respiration Thickness of respiratory membranes 0.5 to 1.0 micrometers edematous (swollen) tissue can be caused by congestion and pneumonia - hinders diffusion leading to hypoxia oxygen deprivation
12. Factors influencing internal & external respiration Surface Area 50-70 square meters for gas exchange Emphysema or cancer Walls of alveoli break down Less surface area for gas exchange
13. Control of Respiration
14. Nerves The phrenic & intercostal nerves transmit impulses to the respiratory muscles Irritation to phrenic nerve is responsible for hiccups (spasm of diaphragm muscle) Neural centers are located in medulla & pons
15. Respiration Rate Terms Eupnea = normal respiration rate Approx 12-15 breaths per min Hyperpnea = higher than normal rate Apnea = No rate Dyspnea = general term for abnormal rate Physical factors, conscious control, emotional factors, and chemical factors all influence rate & depth of breathing.
16. Hyperventilation Deep & rapid respiration, too much CO2 is vented out of the body so: Not enough acid production H2O + CO2 = H2CO3 (carbonic acid) Respiratory alkalosis results Treatment: trap the CO2 and rebreathe it till breathing returns to normal
17. Hypoventilation Slow & shallow respiration with not adequate expiration so CO2 is not vented out of the body Production of excess acid H2O + CO2 = H2CO3 (carbonic acid) Respiratory acidosis results Usually caused by disease process: COPD Asthma Obesity Trauma Pneumonia

18. Disorders of Respiratory System

19. Chronic Bronchitis Symptoms: inflammation of mucosa – chronic mucus production
20. Normal Bronchitis
21. Emphysema Breathing is very labored due to lack of alveolar recoil End stage: Alveolar walls collapse = loss of surface area so less gas diffusion Membranes thicken so decrease in diffusion eventually
22. 4 features in common Both emphysema and chronic bronchitis have: Smoking history Dyspnea = air hunger due to dysfunctional breathing Coughing & pulmonary infections Will develop respiratory failure, hypoxia, acidosis
23. Lung Cancer Basic Info 1/3 of all cancer deaths are due to lung cancers 90% have a smoking history Metastasizes VERY rapidly due to vascularity of lungs
24. Metastasis
25. Squamous cell carcinoma Begins in larger bronchi & bronchioles Forms masses that have bleeding cavities within them
26. Adenocarcinoma Nodules that develop in peripheral areas of lung Develop from alveolar cells & bronchial glands
27. Small cell carcinoma Originate in primary bronchi Grow into small grape like clusters in mediastinum Very aggressive cancer
28. Treatments Resection of diseased portion of lung (thoracotomy) Radiation therapy Chemotherapy
29. Thoracotomy/lung resection
30. Cystic Fibrosis Genetic disorder – recessive Causes oversecretion of thick mucus that clogs respiratory passages Impairs food digestion by clogging ducts that secrete enzymes Multiple other organs are affected
31. Cystic Fibrosis
32. SIDS - Sudden Infant Death Syndrome Sudden, unexplained death of an infant less than 1 year old Possibly caused by brain abnormalities that control respiration, heart rate, or consciousness Environmental factors to reduce risks – sleep on back not on stomach, firm crib with no blankets or stuffed animals or pillows Sudden infant death syndrome (SIDS): Risk factors - MayoClinic.com
33. Asthma Chronically inflamed hypersensitive bronchial passageways Bronchoconstriction of passageways in response to allergen, temperature changes, & exercise Can be managed with medication
34. Hyperbaric Conditions Hyperbaric oxygen chambers – designed to force greater amounts of oxygen into patient’s blood Treats tissues affected by poor circulation
35. How Hyperbaric Treatment Works Patient breathes in regular air while body is under pressure Increased pressure means increased solubility of gases (incl oxygen) More oxygen in blood benefits treatment of certain conditions
36. HBOT used to treat: Tetanus Gangrene Migraines Slow healing wounds Burns/skin grafts Stroke Autism Traumatic Brain Injury Decompression Sickness Cerebral Palsy Multiple Sclerosis Fibromyalgia Many other conditions
37. Scuba Diving The Physics of Diving - Scuba Gas Laws As you go down in depth, the water puts pressure on your body Increased pressure = increased solubility of inhaled gases into the blood
38. Scuba Diving As you come up at the correct rate, the pressure decreases slowly So the solubility decreases slowly So the gases come out of the blood And you can exhale them
39. Scuba Diving If you come up too rapidly, the pressure decreases rapidly So the solubility decreases rapidly So the gases come out of the blood too fast to exhale them properly The excess gas bubbles can collect in joint spaces, arteries, tissues, etc. causing coronary, pulmonary, or brain embolisms
40. Eustachian tubes: FYI Auditory or eustachian tubes provide an avenue for equalizing middle ear pressure with atmospheric pressure via the flow of gases Air will either move in or out of your ears to cause this equalization This is the cause of your ears “popping”
41. Eustachian tubes
42. Laryngitis on your left Notice swollen vocal cords and mucus accumulation
43. Read through the Developmental Aspects section of your notes Developmental Aspects