A Simplified Algorithm for Distinguishing the Major Clinical Causes of Hypoxemia

A Simplified Algorithm for Distinguishing the Major Clinical Causes of Hypoxemia - Flowchart Hypoxemia Hypoxemia

«Flowchart»

Hypoxemia

Shunt

Low V/Q
Hypoventilation

Response to supplemental oxygen

Yes

Hypoventilation

Low V/Q

ABG

(A–a)PO₂ increased

O ₂ (A–a)P(O2) increased

(A–a)PO₂ normal

O ₂ (A–a)P(O2) normal

Asthma
COPD

End

Decrease in respiratory drive

Pulmonary embolism
Intracardiac shunt
AVMs

Pneumonia
Atelectasis

Edema
ARDS

Chest radiograph

Focal opacities

Diffuse opacities

Clear