Comparison of jugular and transverse facial venous sinus blood analytes in healthy and critically ill adult horses.

The study aims to compare results of blood gas, electrolyte, and metabolic analysis between blood sampled from the jugular vein (JV) and transverse facial venous sinus (TFVS) in both healthy and sick adult horses. The research found no significant differences between variables in healthy horses. In sick horses, JV measurements were slightly higher for ionized calcium and glucose, and lower for hematocrit than TFVS measurements. Despite small differences, it suggests TFVS can be interchangeably used with JV for venous blood gas analysis in healthy horses.

Objective of the Study

• The study aims to compare the differences in blood gas, electrolyte, and metabolic analysis results between blood obtained from two different venipuncture sites: the jugular vein and the transverse facial venous sinus.
• The study analyzed two groups of horses: healthy adult horses and sick adult horses presented for emergency evaluation.

Methodology

• The study was conducted as a prospective, experimental study at a large animal university teaching hospital.
• The sample included ten healthy adult horses owned by the University and 48 client-owned adult horses presenting to the hospital’s emergency service for medical or surgical evaluation.
• Preheparinized syringes were used to collect blood from both the jugular vein and the transverse facial venous sinus, prior to the institution of medical therapy.
• Collected samples were analyzed using a point-of-care blood gas analyzer which also reported electrolyte and metabolite results.
• The differences between the two sample sites were analyzed using Student’s paired t-test for normally distributed data and the Wilcoxon paired test for non-normally distributed data.

Results

• For the healthy adult horses, there were no significant statistical differences found between variables for samples obtained from the jugular vein and transverse facial venous sinus.
• For the sick horses, the jugular vein measurements were greater than the transverse facial venous sinus measurements for ionized calcium and glucose, and less than the transverse facial venous sinus for hematocrit.
• However, despite these small discrepancies, the overall agreement between the two sites was demonstrated via Bland-Altman analysis.

Conclusions

• The research concludes that the transverse facial venous sinus can be used interchangeably with the jugular vein for venous blood gas analysis in healthy horses.
• Though there were small differences found in sick horses, these identified differences are not likely clinically important.
• The reliability of the blood gas analyzer used in this study for the measurement of hematocrit remains to be determined.