Blood Gas and Acid‑Base Balance Experiments
BI‑274, Dr. C. S. Tritt
Plots due: 10/17/03

Work in groups of two or three.  Each group should submit one set of plots for this exercise.  You may allocate the work in your group any way you wish, but everyone should understand what was done. Produce plots illustrating the following effects and relationships:

•	The effect of PCO2 or pH on the oxygen partial pressure‑content relationship (the Bohr effect).
•	The effect of hemoglobin saturation on the carbon dioxide partial pressure‑content relationship (the Haldane effect).
•	The relationship among bicarbonate concentration, carbon dioxide partial pressure and pH (attempt to reproduce the pH-bicarbonate diagram). This plot should consist of at least six curves on one set of axis.

Plots should be of engineering quality (have consistent number of significant digits in axis labels, have both vertical and horizontal grids, be labeled with the creators initials and the date created, etc.).

The DOS based BLOOD Program

I wrote the Blood program while working on my Masters degree.  It is starting to show its age (i.e. it's a DOS program written in Pascal), but still provides very good data for the investigation of blood gas and acid-base behavior. The program (and its associated data files) is available for download from http://www.msoe.edu/~tritt/blood.html (download the zip file). Alternately, you can copy the file BLDPRGMS.ZIP from the BI274 folder in my faculty out folder. Then run PowerArchiver (or a similar program) to extract the files to their own folder (c:\blood would be a good choice). Finally, use Start | Run to execute blood.com.

The program will ask you a series of questions regarding how to model blood gas and acid‑base behavior.  I recommend you enter Human for the Lutz file name (other valid file names include pig, mouse, etc. and indicate the species to be modeled).  I recommend you use Kelman's CO2 Content Method.  Select independent pH entry to have the program calculate base excess or decline independent pH entry in which case you'll enter the base excess of the blood and the program will calculate its pH. Select output to the screen and initially accept all the default parameter values (record them in your lab notebook), then proceed with your experiments. During data entry, leaving an entry blank results in its previous value being retained.

Generating the pH-bicarbonate diagrams can be a little tricky. Getting the isobars is relatively easy; you just select independent pH entry and enter a series of pH values and record bicarbonate concentrations for each PCO2. Generating the lines of constant base excess is a little harder. For these lines, decline independent pH entry (this results in the program asking for base excess values). For each Base Excess value of interest, enter a series of PCO2’s and record the generated pH and bicarbonate concentration values for plotting.