Connection And Disconnection Reactions; Electrolytic Effects; Electromagnetic Interference; Product Liability - Enraf Nonius Sonopuls 490 Mode D'emploi

Connection and disconnection reactions

Constant Current (CC) output characteristics may
cause unpleasant connection and disconnection re-
actions if the electrodes are not securely placed or
lose contact with the skin. Make sure the output is
set to 0 mA when you apply or remove the elec-
trodes. Preferably use Constant Voltage (CV) in case
of dynamic application techniques.

Electrolytic effects

Electrolysis occurs under the electrodes when cur-
rent types with a DC component are applied. Be-
cause the greatest concentration of electrolytic
by-products caused by ion migration occur under
the electrodes, we recommend the use of the sup-
plied sponges to keep the effects to a minimum.
Make sure that the sponges are kept well moistened
and place the thick side of the sponge between the
flexible rubber electrodes and the patient.

Electromagnetic interference

Simultaneous connection of a patient to High Fre-
quency Therapy (shortwave or microwave) equip-
ment and an electrical stimulator must not be done
as this may result in burns at the site of the stimulator
electrodes. Therefore, simultaneous connection is
not allowed.
Operation in close proximity (i.e. less than 2 me-
tres) to working shortwave or microwave therapy
units may produce instability in the Sonopuls out-
put. To prevent electromagnetic interference, we
strongly advise using separate mains groups
(phases) for the Sonopuls and the shortwave or mi-
crowave equipment, and a distance of at least 2
metres is kept between the Sonopuls and the
shortwave or microwave equipment. Ensure that the
mains cable of the shortwave/microwave unit does
not come near the Sonopuls or the patient.
If problems with electromagnetic interference per-
sist, please contact your authorised distributor.

Product Liability

A law on Product Liability has become effective in
many countries. This Product Liability law implies,
amongst other things, that once a period of 1 0 years
has elapsed after a product has been brought into
circulation, the manufacturer can no longer be held
responsible for possible shortages of the product.

International safety standard IEC 601-1

This equipment meets the requirements of the In-
ternational Standard for the safety of medical elec-
trical equipment IEC 601-1(general standard), IEC
601-2-5 (standard for ultrasound equipment) and IEC
601-2-10 (standard for electrotherapy equipment /
only Sonopuls 491).
THE THERAPY POSSIBILITIES IN A

Ultrasound therapy

Frequency
The Sonopuls offers a choice of two ultrasound fre-
quencies: 1 and 3 MHz. 3 MHz sound waves are
absorbed relatively strongly by the tissue and con-
sequently have a slightly less deep effect than 1 MHz
waves.
Ultrasoundmode
Both continuous and pulsed ultrasound can be ap-
plied. The advantage of the pulsing sound beam is
that the thermal sensation is suppressed. In this way
it is possible to set a higher intensity than in the case
of continuous ultrasound.
Pulse frequency / duty cycle
The pulse frequency is set at 100 Hz. The duty cy-
cle (= average effective power or ratio pulse dura-
tion: pulse interval) can be altered in 5, 10, 20, 50,
80 and 100 %.

Two pole interferential current

The Sonopuls 491 uses two pole interference, ena-
bling the interferential current to be generated in the
equipment itself, and thus only two electrodes are
needed instead of four.
Carrier wave frequency
This parameter is adjustable in 2, 4 or 10 kHz. De-
pending on the type of nerve fibre (motor/sensory) a
low or high carrier wave frequency may be selected.
Stimulation frequency (AMF)
The stimulation frequency can be adjusted in steps
between 0 and 150 Hz. The choice of setting is de-
pendent on the nature, stage, severity and localisa-
tion of the disorder.
Frequency modulation (spectrum)
This parameter csn be sdjusted in steps between 0
and 100 Hz, and serves to prevent accommodation.
Frequency modulation programs
There are two frequency modulation (sweep) pro-
grams: 6/6 s and 1/30/1/30 s.

Asymmetrical biphasic pulse current (TENS)

Phase duration
The phase duration can be adjusted in steps be-
tween 20 and 400 µs. A short phase duration allows
selective stimulation of the thick fibres.
Stimulation frequency
The frequency can be adjusted in steps between 5
and 200 Hz.
NUTSHELL
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