Adult patients in the ICU were prospectively enrolled from January through
September 2010 with a Pa o 2 /F io 2 ratio , 300 on arterial blood gas (ABG) analysis within 6 h of
a new hypoxemic event or the ICU admission. Focused cardiac and thoracic CCUS was conducted
within 6 h of ABG testing. Causes of AHRF were categorized into cardiogenic pulmonary
edema (CPE), ARDS, and miscellaneous causes aft er reviewing the hospitalization course
in electronic medical records.