Effect of the size of evacuated blood collection tubes on total carbon dioxide concentration in equine plasma.

The research article investigates the effects of the size of evacuated blood collection tubes on the concentration of total Carbon Dioxide (CO2) in horse plasma. It demonstrates that the volume ratio between air and blood significantly influences the CO2 concentration.

Methods

The methodology mainly followed a randomized crossover study design involving a convenient sample of 20 healthy adult horses. Multiple types of evacuated tubes were used to collect jugular venous blood from horses in a random sequence, which includes:

• 2-mL glass
• 2- or 3- mL plastic or plastic plasma separator
• 4- or 6-mL plastic
• 10-mL glass or plastic

The total CO2 concentrations in the plasma were measured using a biochemistry analyzer, and the recorded data were analyzed using repeated-measures Analysis of Variance (ANOVA) and multivariate regression.

Results

The research found that the air volume-to-blood volume ratio was notably higher, and consequently, the plasma total CO2 concentration was considerably lower when blood was collected into 2-mL glass tubes and 2- or 3-mL plastic tubes than when the other five types of evacuated tubes were employed. Concentrations in other types of tubes were found to be statistically equivalent. Besides, researchers detected a linear connection between the total CO(2) concentration and the air volume-to-blood volume ratio.

Conclusion

The research calls attention to the importance of the air-to-blood volume ratio in evacuated blood collection tubes when an accurate estimate of plasma total CO(2) concentration is required. According to their findings, blood samples should be collected into evacuated tubes with a smaller air volume-to-blood volume ratio. This research potentially provides invaluable insights for veterinary clinicians and laboratories for improving the accuracy of CO2 estimation in horse plasma.