A technique for central venous pressure measurement in normal horses.

OBJECTIVE

To investigate a technique of central venous pressure (CVP) measurement using a newly developed catheter in healthy adult horses.

DESIGN

Prospective experimental study.

SETTING

University research facility.

ANIMALS

Twenty healthy adult horses.

INTERVENTIONS

An equine central venous catheter was inserted into the jugular vein to a length of approximately 80 cm from the mid-cervical region in an attempt to catheterize the pulmonary artery. Pulmonary arterial catheterization was confirmed by echocardiography. Insertion distance and pressure were measured at this location with a disposable manometer. The catheter was then withdrawn until presence in the right atrium was confirmed by echocardiography. Insertion distance and pressure were also measured at this location. The catheter was then withdrawn in 5 cm increments until exiting the jugular insertion site with pressure measured at each location. All pressure measurements were taken with the manometer zero position at the point of the shoulder.

MEASUREMENTS AND MAIN RESULTS

Pulmonary artery catheterization was successful in 16 of 20 horses. Mean pulmonary arterial pressure was 23.8 cm H2O (17.5 mm Hg) (95% confidence interval [CI] 20.9-26.7 cm H2O [15.4-19.6 mm Hg]). Mean right atrial pressure was 8.3 cm H2O (6.1 mm Hg) (95% CI 7.1-9.4 cm H2O [5.2-6.9 mm Hg]). Right atrial pressure was compared with pressures recorded at sequential insertion distances and resulted in a recommendation for catheter insertion of at least 40 cm for CVP measurement in adult horses. Jugular venous pressure measurement was statistically different from CVP measurement.

CONCLUSIONS

This catheter measurement technique is well tolerated in normal horses. Routine clinical use of this equine central venous catheter may improve our ability to monitor patients and improve patient care and outcomes of ill horses in hospital.