# 3-Compartment Infusion (plasma and blood data) **URL:** \ **Category:** Phoenix WNL basics\ **Created:** [November 11, 2010, 1:37pm UTC](https://forum.certara.com/t/3-compartment-infusion-plasma-and-blood-data/2240 "2010-11-11T13:37:25Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Helmut\_Schuetz](https://avatars.discourse-cdn.com/v4/letter/h/eb8c5e/32.png) [@Helmut\_Schuetz](https://forum.certara.com/u/Helmut_Schuetz)\ **Post date:** [November 11, 2010, 1:37pm UTC](https://forum.certara.com/t/3-compartment-infusion-plasma-and-blood-data/2240/1 "2010-11-11T13:37:25Z")
Hi! I’m struggling to set up a simultaneous fit (plasma/blood). Both plasma and blood follow a two-compartment model - now I want to set up a 3-Compartment infusion using blood data as one of the peripherals. Any suggestions? ---
**Author:** ![Samer\_Mouksassi](https://avatars.discourse-cdn.com/v4/letter/s/ce7236/32.png) [@Samer\_Mouksassi](https://forum.certara.com/u/Samer_Mouksassi)\ **Post date:** [November 11, 2010, 2:38pm UTC](https://forum.certara.com/t/3-compartment-infusion-plasma-and-blood-data/2240/2 "2010-11-11T14:38:15Z")
Hi Helmut, Are you using Phoenix PML models ? or the classical ? With Phoenix models you can build this model in graphical mode by choosing a 3-CMT model with infusion and then adding an observation (blood) to one of the peripheral compartments. Samer ---
**Author:** ![Helmut\_Schuetz](https://avatars.discourse-cdn.com/v4/letter/h/eb8c5e/32.png) [@Helmut\_Schuetz](https://forum.certara.com/u/Helmut_Schuetz)\ **Post date:** [November 11, 2010, 3:19pm UTC](https://forum.certara.com/t/3-compartment-infusion-plasma-and-blood-data/2240/3 "2010-11-11T15:19:36Z")
Well, first I tried with the classical… If I start with PHX, I’m not sure how to add the second dataset. Right now I have two, one for plasma and one for blood. If I append them (with one additional column stating the matrix) it doesn’t help me either… ---
**Author:** ![ecolby](https://avatars.discourse-cdn.com/v4/letter/e/bb73d2/32.png) [@ecolby](https://forum.certara.com/u/ecolby)\ **Post date:** [November 11, 2010, 3:22pm UTC](https://forum.certara.com/t/3-compartment-infusion-plasma-and-blood-data/2240/4 "2010-11-11T15:22:31Z")
A “merge worksheets” would work, sorting by subject and time, including plasma and blood. ---
**Author:** ![Helmut\_Schuetz](https://avatars.discourse-cdn.com/v4/letter/h/eb8c5e/32.png) [@Helmut\_Schuetz](https://forum.certara.com/u/Helmut_Schuetz)\ **Post date:** [November 11, 2010, 3:31pm UTC](https://forum.certara.com/t/3-compartment-infusion-plasma-and-blood-data/2240/5 "2010-11-11T15:31:20Z")
Is this my stupid day today ? 😉 I’ve tried that before, but now I have two concentration columns. Fine, but how do I link them to the PK model? ---
**Author:** ![ecolby](https://avatars.discourse-cdn.com/v4/letter/e/bb73d2/32.png) [@ecolby](https://forum.certara.com/u/ecolby)\ **Post date:** [November 11, 2010, 3:37pm UTC](https://forum.certara.com/t/3-compartment-infusion-plasma-and-blood-data/2240/6 "2010-11-11T15:37:05Z")
You could edit the Phoenix model graphically, add an observation block, name it something else such as CpObs, and link it to the compartment it is being measured from. Then, in the main mappings panel, there will be a CObs and a CpObs to map the data columns to. ---
**Author:** ![Helmut\_Schuetz](https://avatars.discourse-cdn.com/v4/letter/h/eb8c5e/32.png) [@Helmut\_Schuetz](https://forum.certara.com/u/Helmut_Schuetz)\ **Post date:** [November 11, 2010, 3:48pm UTC](https://forum.certara.com/t/3-compartment-infusion-plasma-and-blood-data/2240/7 "2010-11-11T15:48:13Z")
Wow, THX – you made my day! ---
**Author:** ![ecolby](https://avatars.discourse-cdn.com/v4/letter/e/bb73d2/32.png) [@ecolby](https://forum.certara.com/u/ecolby)\ **Post date:** [November 11, 2010, 3:49pm UTC](https://forum.certara.com/t/3-compartment-infusion-plasma-and-blood-data/2240/8 "2010-11-11T15:49:17Z")
You’re welcome! 🙂