4. Ventilation / Perfusion

Study Guide

What is ventilation

What is perfusion

Where is perfusion highest in the lung and why

What is the average, normal V/Q ratio across the lungs?

What value makes up ventilation?

What value makes up perfusion

How is the ratio affected by an airway obstruction? Would this decrease or increase the ratio?

How is the ratio affected by pulmonary (blood flow) obstruction? Would this increase or decrease the ratio?

What do the partial pressures of gasses look like in these scenarios?

How does the body make local adjustments to perfusion with changes in alveolar ventilation?

W

what happens to perfusion is alveolar ventilation is low?

What happens to alveolar perfusion is alveolar ventilation is high?

What is a shunt?

What happens to PO2 levels in arterial blood with a shunt?

In general, what are some different types of shunts?

What is the difference between hypoxemia and hypoxia?

How is hypoxemia measured?

How can hypoxemia be corrected (depending on what’s causing it)?