PH
All arterial blood gas (ABG) results (FIO2, PO2, CO2, & PH) should be obtained from the same specimen. Use the PH value from the worst ABG result you have selected for a patient during their first 24 hours in ICU.
- though there are different collection practices used when selecting the PH value, the original APACHE II user manual (version 1.0) is as above.
