Chapter 9: Non-invasive Blood Pressure
Veterinary 3 Parameter Advisor
®
Operation Manual
9-3
NIBP Theory of Operation
The 3 Parameter Advisor
®
Vital Signs Monitor uses oscillometric principles to calculate the systolic, diastolic and
mean arterial pressure values from the blood pressure cuff. When the blood pressure cuff is inflated it creates an
occlusion of the artery on the limb being used. The cuff is then deflated by a set amount of pressure in the cuff.
When an oscillometric pulse is identified, another similar pulse must also be identified and measured before it
steps down again. This method of measuring blood pressure ensures the measurement is a true measurement
and not a change in the cuff due to motion. If the measurement is not reproduced a second time, it is not
recorded and the pressure is stepped down. Once two identical oscillations are obtained the cuff deflates. In
other words, it will only capture readings that are reproduced; if there are no similar oscillations at that pressure,
the reading is discarded as artifact. This type of oscillometric technology is more motion tolerant and generally
produces a higher success rate than other NIBP technologies.
Attaching the Patient
Choose a blood pressure cuff appropriate for the patient and the limb size by measuring the circumference
1.
of the limb. See the table below.
WARNING! Blood pressure measurements may be inaccurate if cuffs and/or hoses other than those
specified by Smiths Medical PM, Inc. are used. (SurgiVet
®
brand)
NOTE! The NIBP Cuff Kit is latex-free.
LIMB CIRCUMFERENCE
CUFF
3 – 9 cm
Extra small (SurgiVet
®
part
number 31543B1)
5 – 15 cm
Small (SurgiVet
®
part
number 31543B2)
9 – 25 cm
Medium (SurgiVet
®
part
number 31543B3)
17 – 41 cm
Large (SurgiVet
®
part
number 31543B4)
Cuff Warranty
Cuffs carry a six-month warranty, pending evaluation by Smiths Medical PM, Inc. Technical Services.
Cuffs that
are contaminated, have liquid in them, have been misused/abused, or are older than six months will not
be covered under the warranty.
CAUTION! Extremity and cuff motion should be minimized during blood pressure determinations.
CAUTION! Proper blood pressure cuff size and placement are essential to the accuracy of the blood
pressure determination.
CAUTION! Any blood pressure recording can be affected by the position of the patient, his or her
physiologic condition, and other factors.