Objective—To describe the pulsed-wave Doppler
tracing of the equine lateral palmar digital artery and
its modification in relation to standardized changes in
Animals—17 healthy Saddlebred horses.
Procedure—Pulsed-wave Doppler examinations of
left and right lateral palmar digital arteries of the horses
were performed. The baseline examination was
performed on each forelimb while horses were standing
squarely with the body weight equally distributed
among the 4 limbs (BED position). For each forelimb,
the examination was repeated during 3 standardized
modifications of the horse's posture (non–weightbearing
[NWB] position, full weight-bearing [FWB]
position, and a position involving hyperextension of
the distal interphalangeal joint [HE position]). In each
position, mean values of systolic peak velocity, first
and second diastolic peak velocity, end-diastolic
velocity, mean velocity, and resistive index were calculated.
Data obtained in each different posture were
Results—No significant differences in blood flow variables
were detected between the left and right forelimbs.
However, significant differences were detected
in values of first diastolic velocity, second diastolic
velocity, mean velocity, and resistive index between
the NWB position and FWB position. Also, end-diastolic
velocity in the NWB position was significantly different
from that recorded in the HE position.
Conclusions and Clinical Relevance—The pulsedwave
Doppler tracing of the equine lateral palmar digital
artery was modified considerably with changes in
posture. This suggests that the use of a precisely standardized
posture for horses is required to obtain repeatable
data. (Am J Vet Res 2004;65:1211–1215)