| EFC | elastin fragment concentration; endogenous fecal calcium; ephemeral fever of cattle |
|---|---|
| ETCO2 | end-tidal carbon dioxide [concentration] |
| ETPCO2 | end-tidal partial carbon dioxide [concentration] |
| FECO2 | fractional concentration of carbon dioxide in expired gas |
| FEO2, | FEO2 fractional concentration of oxygen in expired gas |