Likewise , the association between VD/VT and mortality was significant on study day @ ( odds ratio per @ change in V ( D ) / V ( T ) -LSB- @ % CI -RSB- : @ -LSB- @-@ @ -RSB- P = @ ; and study day @ : @ -LSB- @-@ @ -RSB- P = @ ) after adjusting for V ( D ) / V ( T ) , P ( aO@ ) / F ( IO@ ) , oxygenation index , vasopressor use , and the primary risk for ARDS .