Term
| tidal volume? normal amount? which two volumes make this? |
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Definition
| volume inspired & expired w normal breath. about 500 ml. Dead space volume + Alveolur volume = Vt. |
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Term
| IRV (inspiratory reserve volume). when used? |
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Definition
| volume that can be inspired above the tidal volume. used in exercise. |
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Term
| expiratory reserve volume |
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Definition
| volume that can be expired after tidal volume. |
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Term
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Definition
| remaining volume in lung after forced expiration - cannot be expired or measured via spirometry |
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Term
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Definition
| tidal volume X breaths/min |
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Term
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Definition
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Term
| functional residual capacity. what volume is expired to get this? measure? |
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Definition
| sum of ERV & residual volume. volume remaining after tidal volume is expired. includes residual volume thus can't be measured via spirometry. |
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Term
| vital capacity / forced vital capacity. describe this volume. |
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Definition
| sum of tidal volume & IRV & ERV. volume that can be forcefully expired after inspiration. |
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Term
| total lung capacity. Describe this volume. Measure? |
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Definition
| all four lung volumes. the amount in lung after full inspiration. can't be measured cuz it includes the residual volume. |
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Term
| FEV (forced expiratory volume). what percentage of vital capacity? affect of asthma? and fibrosis? |
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Definition
| the amount that can be expired in one second. normally 80% of vital capacity. Asthma = obstructive thus reduces FEV1 only and ratio of FEV1/FVC is reduced. Fibrosis = restrictive lung disease, thus it reduces both the FEV1 & FVC equally, so there's no change in ratio. |
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Term
relationship of compliance to elastance of the lung
what about to recoil? |
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Definition
inverse relationship
compliant lungs have low recoil, while stiff lungs have high recoil |
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Term
compliance on graph? what is compliance? calculation?
what is relationship between compliance & airflow? |
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Definition
slope of the pressure-volume curve. compliance is the distensibility of the lung.
CL = ΔV/PTP
V = lung volume
P = transpulmonary pressure
high C means more airflow for a given pressure |
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Term
| For emphysema, what property of the lung is increased, which is decreased? which way does this shift the FRC on the lung-chest wall system? |
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Definition
| compliance is increased. elastacity is decreased. FRC is shifted up. |
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Term
| For fibrosis, what property of the lung is increased, which is decreased? which way does this shift the FRC on the lung-chest wall system? |
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Definition
| compliance is decreased (hard to expand lungs), tendency for the lungs to collapse is increased (increased recoil). FRC is shifted downward. |
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Term
| collapsing pressure of large alveoli, low or high? |
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Definition
| low thus easy to keep open |
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Term
| collapsing pressure for small alveoli? what prevents collapse? |
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Definition
| large thus harder to keep open. Surfactant. |
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Term
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Definition
| reduces surface tension thus prevents alveolur collapse. |
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Term
| calculation of air flow? where is the highest resistance? how can an asthma pt reduce airway resistance? |
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Definition
| Pressure divided by Resistance. Highest R in the medium sized bronchi, not in smallest bronchioles cuz there are so many of them in parrallel. Asthma pt breathe at a higher lung volume thus with more air in lungs the resistance is lower. |
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Term
| At rest, what is alveolur pressure? what lung volume is present? What's interpleural pressure? What's this pressure caused by? |
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Definition
| Alveolur pressure = 0. Lung volume = FRC. Interpleural P = negative cuz the chest wall is trying to expand and lung is trying to collapse. |
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Term
| during inspiration, what is alveolur pressure? what is lung volume at the end of a normal inspiration? What is interpleural pressure? |
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Definition
| Alveolur P = negative. Lung volume becomes Tidal Volume (1 breath). Interpleural P becomes more negative. |
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Term
| Asthma & COPD. Type of respiratory disease? Which properties of the lung are decreased / increased? |
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Definition
| Obstructive disease (narrowing of airways). FVC (forced vital cap) is decreased, FEV (forced expiratory volume) is decreased. FRC (functional residual capacity) is increased (cuz not all the air is exhaled, but trapped in lungs). |
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Term
| Fibrosis. Type of respiratory disease? what lung properties are decreased / increased? |
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Definition
| Restrictive disease. compliance is decreased (inspiration impaired). Decrease in all lung volumes. Both FEV1(forced expiratory volume per second) & FVC (forced vital capacity) is unchanged. FRC (functional residual capacity) is decreased. |
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Term
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Definition
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Term
| Calculation for Partial Pressure of a gas. |
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Definition
| Px = Fx (PB - PH20), where Fx = fraction of that gas. PH20 = vapor pressure. |
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Term
| calc Alveolar ventilation |
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Definition
(VT - VD) X (breathing freq)
VT = alveolar volume
VD = dead space volume |
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