Patho Exam 1 Respiratory Flashcards
1
Q
Define a high V/Q ratio
A
Poor perfusion of well ventilated lung tissue
2
Q
Define a low V/Q ration
A
Poor ventilation of well perfused lung tissue
3
Q
Define alveolar dead space
A
An area where alveoli are ventilated but not perfused
4
Q
Shunting occurs when?
A
Inadequate ventilation of well perfused lung tissue (Low V/Q)
5
Q
Examples of Low V/Q
A
Atelectasis, Asthma, Pneumonia, Pulmonary Edema
6
Q
Most common cause of a high V/Q?
A
Pulmonary Embolism
7
Q
Why would someone with emphysema or fibrosis die from hypoxia rather than hypercapnia?
A
Because even with the impaired diffusion of O2 across the aveolocapillary membrane CO2 can still freely diffuse.
8
Q
Clinical definition of Acute Respiratory Failure
A
PaO2 50 mmHg
and
pH
9
Q
What are the three main causes of Pulmonary Edema?
A
- LHF -leading to increased capillary hydrostatic pressure
- Injury to the capillary epithelium - Increases permeability leading to increased interstitial oncotic pressure
- Lymph system blockage
