Zimmer A.T.S. 2000, Operators & Service Manual

Page: 7 / 32

5
• In case of failure, the tourniquet cuff must be fully de-
flated and the limb exsanguinated again before reinfla-
tion. Reinflation over blood-filled vasculature may lead
to intravascular thrombosis.
• Tourniquet users must be familiar with the inflation-
deflation sequence when using a dual-cuff tourniquet,
or two tourniquet cuffs together for IVRA (Bier Block
anesthesia), so that the wrong tourniquet will not be
released accidentally.
• Test for hemoglobin type and level before using a
tourniquet on patients with sickle-cell anemia. When the
tourniquet is used for these patients, the limb should be
carefully exsanguinated and the PO
2
and pH should be
closely monitored.
• Select the proper cuff size to allow for an overlap of
about 3 to 6 inches (7.6 to 15.2 cm). Too much overlap
may cause cuff rolling and telescoping, and may lead
to undesired pressure distribution on the limb. The
skin under the tourniquet cuff must be protected from
mechanical injury by smooth, wrinkle-free application
of the cuff. If the tourniquet cuff is applied over any
material that may shed loose fibers (such as Webril) the
fibers may become embedded in the contact closures
and reduce their effectiveness. As an under padding, a
section of stockinette may be used. The deflated cuff
and any underlying bandages should be com-
pletely removed as soon as tourniquet pressure
is released. After the cuff has been fully deflated
and removed from the patient, the unit can be set
to STANDBY. Even the slightest impedance of venous
return may lead to congestion and pooling of blood in
the operative field.
• If skin preparations are used preoperatively, they
should not be allowed to flow and collect under the cuff
where they may cause chemical burns.
• Whenever the tourniquet cuff pressure is released, the
wound should be protected from blood surging back by
applying pressure dressings and, if necessary, elevat-
ing the limb. Transient pain upon tourniquet pressure
release can be lessened by elevation of the limb. If
full color does not return within 3 to 4 minutes after
release, the limb should be placed in a position slightly
below body level.
• Whenever Intravenous Regional Anesthesia (IVRA, a
Bier Block anesthesia) is used, it is recommended that
the tourniquet remain inflated for at least 20 minutes
from the time of injection.
1.6 ADVERSE EFFECTS
A dull aching pain (tourniquet pain) may develop throughout the limb
following use.
Pathophysiologic changes due to pressure, hypoxia, hypercarbia,
and acidosis of the tissues occur and become significant after about
1 1/2 hours of tourniquet use. Symptoms of tourniquet paralysis are
motor paralysis and loss of sense of touch, pressure, and proprio-
ceptive responses.
Intraoperative bleeding may be caused:
1. By the slight impeding effect exerted by an unpressurized cuff
(and its padding, if used), which prevents venous return at the
beginning of the operation.
2. By blood remaining in the limb because of insufficient exsangui-
nation.
3. By inadequate tourniquet pressure (between systolic and
diastolic blood pressure of the patient), or slow inflation and de-
flation, all of which allow arterial blood to enter while preventing
venous return.
4. By blood entering through the nutrient vessels of the long
bones, such as the humerus.
SECTION 2.0
A.T.S. 2000 TOURNIQUET SYSTEM
INSTALLATION & OPERATING
INSTRUCTIONS
2.1 INITIAL INSPECTION
Unpack the A.T.S. 2000 Tourniquet upon receipt and
inspect the unit for any obvious damage that may have oc-
curred during shipment. We recommend that this inspection
be performed by a qualified biomedical engineer or other
person thoroughly familiar with electronic medical devices.
If the unit is damaged, notify the carrier and your Zimmer
representative immediately. If the initial inspection results
are satisfactory, a functional and calibration check should
be performed.
2.2 FUNCTIONAL AND CALIBRATION CHECK
The unit shall produce the results explained in the follow-
ing steps, exactly as indicated. Failure to do so indicates
that the device is not to be used until necessary repairs are
made.
1. Connect the power plug to the power entry module on
the back of the unit, then plug the unit into a source of
power compatible with the unit’s power rating.
a) Observe that the ~ (AC) indicator is on.
b)
Unit should be connected to A/C power 24
hours before initial use.
2. Turn the unit on by pressing the ON/STANDBY ( I/O )
touch-switch and observe the following:
a) A series of zeros and asterisks appear on the
PRESSURE and TIME displays;
b) The unit emits three tones; high, medium, low;
c) The word “SELF” appears in the main PRESSURE
display and the word “TEST” appears in the main
TIME display;
d) The word “VER” appears in the second PRES-
SURE display and the software version number
appears in the second TIME display;
e) The Alarm Silence Switch illuminates;
f ) The word “CAL” appears in both PRESSURE dis-
plays;
g) The PRESSURE and TIME displays all read zeros.
3. Test the PRESSURE set point system as follows:
a) Press and hold the main PRESSURE INCREASE
(+) or DECREASE (–) touch-switch;
b) The PRESSURE display reads “*250”, the default
pressure set point, for approximately 1.5 seconds;
c) The main PRESSURE display increases (or de-
creases) by units of one until reaching a multiple of
5. Then the main PRESSURE display increases (or
decreases) by units of 5 to a maximum of 475 (or a
minimum of 0), thus altering the pressure set point;
d) Releasing the touch-switch causes the sensed
pressure of “0” to be displayed;
e) Once again, press the main PRESSURE IN-
CREASE (or DECREASE) touch-switch; the main
PRESSURE display should read the last setting
from step c (above);
f) Release the main PRESSURE touch-switch;
g) Repeat steps
a
through
f
above for the second
PRESSURE display functional check.