Term
| What is the respiratory exchange ratio at rest and during exercise? |
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Definition
respiratory exchange ratio = CO2 production/ O2 consumption at rest = 0.8 during exercise = 1.0 |
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Term
| What is the O2 consumption at rest and during exercise? |
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Definition
at rest VO2 = 250 ml/min during exercise VO2 = 3000 ml/min |
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Term
| What are some substances that will cause bronchodilation? |
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Definition
Beta 2 agonists 1) EPI 2) albuterol - in asthma inhalers 3) isoproterol |
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Term
| Explain the relationships between pressure, volume, and temperature |
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Definition
Boyle's Law P1V1 = P2V2 P and V are inversely related Charles' Law P and V are directly related to T General Gas Law P1V1/T1 = P2V2/T2 |
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Term
| How is O2 partial pressure calculated? |
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Definition
PO2 = PB*FO2 PB = barometric pressure = 760 mm HG FO2 = fractional concentration of oxygen, normally 21% |
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Term
| What is the partial pressure of water vapor? |
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Definition
47 mm Hg *must be taken into account when doing calculations with inspired air |
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Term
| What is the partial pressure of O2 at different parts of the respiratory system? |
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Definition
Air - 160 mm Hg Trachea - 150 mm Hg Alveoli - 100 mm Hg Arterial - 100 mm Hg Mixed venous - 40 mm Hg |
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Term
| What are the partial pressure values of CO2 at different parts of the respiratory system? |
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Definition
Air - 0 mm Hg Alveoli - 40 mm Hg Arterial - 40 mm Hg Mixed venous - 46 mm Hg |
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Term
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Definition
| The volume inspired or expired in a single normal breath - normally 500 mL |
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Term
| What is inspiratory reserve volume? |
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Definition
| The additional volume to the tidal volume that can be maximally inspired |
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Term
| What is expiratory reserve volume? |
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Definition
| The volume additional to tidal volume that can be maximally expired |
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Term
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Definition
The volume left in the lungs after maximum expiration NOTE - cannot be measured directly by spirometer |
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Term
| What is inspiratory capacity? |
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Definition
| The maximum volume that can be inspired in a single breath - tidal volume + inspiratory reserve volume |
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Term
| What is functional residual capacity? |
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Definition
The amount of volume left in the lung after a normal expiration Equilibrium point NOTE - cannot be measured directly by spirometer |
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Term
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Definition
AKA forced vital capacity the maximum volume of air that can be exhaled after a maximum inspiration expiratory reserve volume + tidal volume + inspiratory reserve volume |
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Term
| What is total lung capacity? |
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Definition
the total volume of the lung NOTE - cannot be measured directly by spirometer |
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Term
| What are the lung volumes that cannot directly measured by spirometry? |
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Definition
1) residual volume 2) functional residual capacity and 3) total lung capacity - both based off residual volume |
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Term
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Definition
Forced expiratory volume of air exhaled in 1 second normal FEV1/FVC ratio = 0.8 or 80% *obstructive diseases (asthma) - FEV1/FVC ratio decreased, FEV1 decreased, FVC decreased *restrictive diseases (fibrosis) - FEV1/FVC ratio the same or increased, FEV1 decreased, FVC decreased FEF25-75% is affected the same as FEV1/FVC ratio |
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Term
| What is the alveolar ventilation equation? |
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Definition
PACO2 = (VCO2 * K)/ VA very important relationship. K is constant so alveolar ventilation must increase when CO2 production increases to maintain a constant partial pressure of CO2 in the alveoli |
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Term
| How can PAO2 be calculated using the alveolar gas equation? |
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Definition
PAO2 = PIO2 - (PACO2/R) PIO2 = partial pressure of inspired oxygen PACO2 = partial pressure of carbon dioxide in alveoli R = respiratory exchange ratio |
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Term
| What is transmural pressure? |
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Definition
Includes two types Transpulmonary pressure (PL) = PA (alveolar pressure) - Ppl (pleural pressure) Transairway pressure (Pta) = Paw (airway pressure) - Ppl (pleural pressure) *before inspiration Ppl = -5 *during inspiration Ppl= -8 during expiration Ppl = -5 |
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Term
| How can diseases affect lung compliance? |
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Definition
*increase compliance - pulmonary emphysema - the exception *decrease compliance pulmonary fibrosis pulmonary vascular congestion pneumonia pleural effusion decreased surfactant spine deformity obesity |
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Term
| How does surface tension relate to alveolar stability? |
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Definition
P = 2T/r P - pressure in the alveoli T - surface tension r - alveolar radius *surfactant reduces surface tension thus reducing pressure and promoting alveolar stability |
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Term
| What are the causes of reduced surfactant activity? |
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Definition
1) neonatal respiratory distress syndyome 2) adult respiratory distress syndrome 3) post cardio-pulmonary bypass 4) pulmonary embolus 5) oxygen toxicity and other agents |
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