Evaluation of a new oscillometric blood pressure monitor in isoflurane-anesthetized dogs.
OBJECTIVE
This study was conducted to evaluate the performance of a new veterinary oscillometric noninvasive blood pressure (NIBP) monitor in anesthetized dogs.


METHODS
Assessment was made to determine how closely indirect measurements were associated with direct measurements, and if there were statistically significant differences between the measurements by site.


METHODS
Six mongrel dogs weighing 27.8 +/- 2.9 kg.


METHODS
Dogs were anesthetized with thiopental and maintained with isoflurane, which was delivered with controlled ventilation. Direct pressure measurements were obtained via a percutaneously placed arterial catheter. A range of systolic arterial pressures (SAP) were achieved by changing the isoflurane concentrations. Sites of cuff placement for indirect measurements were identified as metacarpus, metatarsus, and anterior tibial.


RESULTS
At pressures below 80 mm Hg, indirect systolic measurements averaged 4 +/- 3 mm Hg, higher than the direct values. At normal and high levels, indirect systolic measurements underestimated direct values by 18 +/- 6 and 23 +/- 6 mm Hg, respectively. Diastolic and mean pressure measurements followed the same trend, with indirect values being lower than the direct arterial pressures. Systolic, diastolic and mean arterial pressure measurements differed by cuff-placement site.


CONCLUSIONS
When analyzed by site and level, indirect systolic and mean arterial blood pressures during hypotension were essentially the same as direct pressures. However, at pressures within the normal or high range, indirect measurements underestimated the direct pressures.


CONCLUSIONS
Noninvasive blood pressure measurements with a new oscillometric monitor provided an excellent means of detecting arterial hypotension in anesthetized dogs. The metatarsal site for cuff placement was slightly better than the metacarpal or anterior tibial site, considering that the regression line was closest to complete equality between the indirect and direct measurements for SAP.
Sawyer
Donald C
DC
Department of Physiology, Michigan State University, E Lansing, Michigan 48824, USA. DSESI@aol.com
Guikema
Audra H
AH
Siegel
Erin M
EM
D000758:Anesthesia / Q000662:veterinary*; D018685:Anesthetics, Inhalation / Q000008:administration & dosage*; D000818:Animals; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000295:instrumentation / Q000379:methods / Q000662:veterinary; D015924:Blood Pressure Monitors / Q000592:standards / Q000662:veterinary*; D004285:Dogs / Q000502:physiology*; D004867:Equipment Design; D007530:Isoflurane / Q000008:administration & dosage*; D015203:Reproducibility of Results
D018685:Anesthetics, Inhalation; D007530:Isoflurane