LE 5002 Non Invasive Blood Pressure Meter
USER MANUAL
17
7. FACTORS TO TAKE INTO ACCOUNT
The technique for carrying out indirect (non invasive) blood pressure measurements
does not offer immediate results. It requires a process of adaptation by the animals,
proper placement of transducer and cuff and suitable environmental conditions.
Generally, simply placing the transducer and cuff on the animal, making the necessary
connections, switching on the instrument and starting to take measurements without any
further ado will not offer satisfactory results.
This section proposes a number of recommendations that should be followed by the
experimenter.
7.1.
ON THE PLACEMENT OF THE PRESSURE CUFF
AND PULSE TRANSDUCER
Generally, the position of pressure cuff and pulse transducer on the animal tail is not
critical.
Normally, the user decides on the most suitable placement in the initial measurement,
naturally taking into account the fact that the decision will be guided by a transducer
position that makes it possible to obtain the highest pulse signal, and where occlusion is
easiest. This should always be done with the animal properly prepared (See
Vasodilatation).
This manual describes some tips that are for guidance only:
•
The animal’s tail should be kept clean. This will improve contact between skin,
cuff and pulse transducer.
•
The cuff-pulse transducer unit can be used either together or separately. There is
no need to press the tail excessively with the transducer. The pressure applied by
the spring is sufficient to keep it attached to the tail, and also increases its
sensitivity.
•
To avoid minor tail movements that may cause artefacts, and improve transducer
contact at the same time, it should be held using the guide on the accessory plate
of the PANLAB traps (ref. LE 5095, in which case it is a good idea to work with
the cuff/transducer jointly).
•
Place the transducer over the end of the tail, normally 2 or 3 cm from the end,
where the tissue has less muscular mass and pulse sensitivity is greater. Place
the cuff, before the transducer, about 2 or 4 cm from the former. Greater
distances between both devices may give rise to parasitic movements.
Obviously, the above measurements are valid for rats and not for mice.
•
Due to the characteristic vascular system of the mouse’s tail, the diametric
position of the transducer may be fundamental to facilitate detection of a pulse.
