respiratory disease Flashcards
low PO2
hypoxemia
low O2 in tissues
sciencey word
what does it result from
- hypoxia
2. results from inadequate oxygen delivery to meet tissue oxidative requirements
causes of hypoxemia
respiratory (4)
other (4)
respiratory:
1. reduced inspired O2 tension
2. alveolar hypoventilation (air not moving in and out)
3. impairment of diffusion (ie fibrotic tissue)
4. venous/ perfusion mismatch
others:
1. blood volume loss
2. anemia
3. carbon monoxide
4. hypothermia (lower temp => RBC holding onto O2)
hypercapnia (def [actual #] and cause)
- increase in PaCO2 >45 torr
2. from inadequate alveolar ventilation in relation to metabolic production of CO2
hypocapnia (def [actual #] and what it causes)
- low PaCO2 <35 torr
2. increases ventilation
restrictive lung dysfunction (3)
2 basics
1 hallmark of disease*
- abnormal reduction in pulmonary ventilation, lung expansion is diminished
- everything is smaller => less volume of gas moving in and out
- hallmark of disease is flow rate stays the same, just the volume decreases
obstruction lung dysfunction (2)
- diseases of respiratory tract which produce obstruction to airflow
- can ultimately affect mechanical function and gas exchange capability
compliance (def)
- link to P exerted on wall and amt of air lungs can have
pathogenesis of restrictive lung disease (4)
(whats increasing or decreasing)
- compliance of chest wall and lung decrease => lung is not fully inflated
- lung volumes decrease (IRV, tidal volume, and ERV is reduced)
- work of breathing increases and we recruit accessory muscles
- RR increases because we need to breath more to maintain minute volume (more breaths with less O2)
identifying RLD by spirometry
what measures do we use
what happens to shape
what results do we consider diseased
- TLC and VC are the two most common measures used to identify RLD
- on the spirograph the shape is the same, just smaller
- if change of 20% (in either direction) we consider person diseased
clinical manifestations of RLD
signs (6)
symptoms (3)
signs:
1. tachypnea
2. hypoxemia
3. decreased breath sounds on auscultation
4. decreased lung volumes
5. decreased diffusing capacity (because of widening of interstitial spaces)
6. cor pulmonale
symptoms:
1. dyspnea (complaint of shortness of breath)
2. cough- dry/ non-productive (*opposite from OLD)
3. emaciation - because breathing causes shortness of breath
cor pulmonale (def and what it can lead to)
- right side heart failure because pressures got so high
2. can lead to pulmonary hypertension
pathogenesis of OLD (4)
what happens to flow rates? why?
loss of elastic recoil leads to what?
whats increasing or decreasing? (2)
- altered expiratory flow rate because narrowing => increased airflow resistance
- loss of elastic recoil because airways tend to collapse which leads to hyperinflation
- increased residual volume
- work of breathing increases
4 pathological (physical) changes (in bronchi) resulting from OLD
- increased mucus prodiction/ impaired secretion
- inflammation of mucosal lining of the bronchi and bronchioles
- muscosal thickening
- spasm of bronchial smooth muscle
why work of breathing is increased with obstructive lung disease (4)
- respiratory muscles must work harder to overcome increased airway resistance
- diaphragm excursion may be limited due to hyperinflation of lungs
- alveolar ventilation is reduces because hyperinflated areas cause distortions of perfusion areas
- alveolar- capillary membrane surface area may be reduced