Effect of body position on indirect measurement of systolic arterial blood pressure in dogs.

OBJECTIVE

To determine whether a difference existed in Doppler ultrasonographic measurements of systolic arterial blood pressure (SAP) in sitting versus laterally recumbent dogs and to determine the degree of variability in measurements made in each position.

DESIGN

Diagnostic test evaluation.

ANIMALS

51 healthy or sick adult dogs, without recent sedation or anesthesia and with an SAP ≤ 300 mm Hg.

PROCEDURES

In a crossover design, SAP was measured via Doppler ultrasonography when dogs were sitting (on hind limbs with nonmeasured forelimb bearing weight) and laterally recumbent, with the cuff position at the level of the right atrium for both positions. Seven measurements were obtained per position for each dog.

RESULTS

Mean ± SD SAP was significantly higher in the sitting (172.1 ± 33.3 mm Hg) versus recumbent (147.0 ± 24.6 mm Hg) position, and this difference was evident for 44 of 51 (86%) dogs. The mean difference in measured SAP between the 2 positions was 25.1 ± 28.5 mm Hg. Blood pressure measurements had a significantly higher repeatability in the recumbent position than in the sitting position.

CONCLUSIONS AND CLINICAL RELEVANCE

Blood pressure measurements in dogs were significantly affected by body position, and they were higher for most dogs when sitting rather than laterally recumbent. Blood pressure measurements in the laterally recumbent body position were less variable than in the sitting position.