Related Experiment Videos
An evaluation of three methods for determining colloid osmotic pressure
M M Blackwell1, J Riley, M McCall
1Program of Extracorporeal Circulation Technology, Clinical Services Department, Medical University of South Carolina, Charleston 29425.
The Journal of Extra-Corporeal Technology
|December 9, 1993
Summary
Estimating plasma colloid osmotic pressure (COP) using total serum solids (TSS) is a reliable alternative to direct measurement. This method, particularly the derived equation, offers accurate assessment for clinical applications.
Area of Science:
- Cardiovascular Physiology
- Clinical Chemistry
Background:
- Plasma colloid osmotic pressure (COP) is crucial for regulating fluid balance and preventing edema.
- Accurate COP measurement is vital in managing patients, especially those undergoing complex procedures like cardiopulmonary bypass.
Purpose of the Study:
- To compare direct COP measurement with estimations derived from serum total protein and total serum solids (TSS).
- To validate a regression equation for estimating COP from TSS.
Main Methods:
- Blood samples were collected from 20 adult patients during cardiopulmonary bypass surgery at three distinct time points.
- COP was directly measured using a colloid osmometer and estimated using serum total protein and TSS.
- Statistical analysis included two-way ANOVA, Bonferroni correction, and linear regression.
Main Results:
- A statistically significant difference (p < 0.01) was observed among the three COP assessment methods.
- A regression equation (COP = (3.02 * TSS) + 0.65) was developed to estimate COP from TSS.
- Prospective testing (n=38) showed a strong correlation (R² = .932) and no significant difference between direct COP measurement and TSS estimation.
Conclusions:
- Estimation of COP from TSS using the derived equation is a valid and accurate method.
- This TSS-based estimation offers a practical alternative to direct COP measurement in clinical settings.