Fig. 1.
Study flow chart. CXR chest x-ray, FiO2 fraction of inspired oxygen, PaO2 partial pressure of oxygen, SpO2, pulse oximetric oxygen saturation, U/S ultrasound
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.