Hemochron 801, 401 User manual

OPERATOR’S MANUAL

Models 801 & 401

Table of Contents

Summary & Explanation 2

Principle of the Procedure 3

Principle of Operation 4

Features 5

Specifications 8

Operating Instructions 9

Operating Cautions & Limitations 10

Performance (Expected Values) 12

Quality Control 13

Service & Maintenance 15

Troubleshooting 24

Replacement Parts 26

Suggested Reading 28

For in vitro Diagnostic Use

S

ummary

&

E

xplanation

he HEMOCHRON®instru­ments (Models 401 and 801)
are portable, battery oper-

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perform an array of whole blood
coagulation tests at any patient loca­tion. The Model 401 instrument has
one test well for single or sequential
test determinations. The Model 801
instrument has two individual test
wells allowing for the simultaneous
performance of two coagulation tests.
It is ideal for running the same test in
duplicate or for measuring two
different coagulation tests simultane­ously. The operation of both the 401
and the 801 Models is the same.

ated instruments designed to

The HEMOCHRON is manufactured
and quality assured by skilled tech­nical personnel using high quality test
instruments. Our Quality Assurance
team uses rigorous standards to eval­uate and certify each machine. The
HEMOCHRON instrument complies
with CSA, L.A. County, and IEC stan­dards as well as many other state and
city codes.

Under routine operating conditions,
the HEMOCHRON instrument will
provide uninterrupted trouble-free
service. The HEMOCHRON is sold
with a Limited Warranty which is
published in this manual.

2

P

rinciple of the

P

rocedure

here are two pathways which
comprise the overall coagula­tion cascade: The intrinsic

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There are twelve clotting factors or
proteins involved in this cascade
scheme. They are numbered I through
XIII, excluding factor VI which was
incorrectly used to label an extrinsic
factor.

The intrinsic pathway is so named
because all the proteins needed for the
entire process are contained within the
blood. The following clotting factors
are unique to this pathway: XII, XI,
IX, and VIII. The extrinsic mechanism
requires a substance outside of the
blood, tissue factor (Factor III), to
initiate the pathway. Only Factor VII is
unique to this pathway. The extrinsic
pathway of coagulation is much faster
than the intrinsic.

and the extrinsic pathways.

Common to both the intrinsic and
extrinsic pathways are Factor X,
prothrombin, thrombin, fibrinogen and
fibrin.

The HEMOCHRON system allows one
to conduct in vitro diagnostic coagula­tion tests at the patient bedside to
ensure accurate assessment of patient
hemostasis.

3

P

rinciple of

O

peration

he HEMOCHRON instrument
was introduced commercially
in 1969 as a convenient

T

time-consuming and subjective Lee­White and manual activated clotting
time procedures. The Models 401 and
801 provide many features for ease of
use and reliability.

The HEMOCHRON system has enjoyed
widespread use during cardiopul­monary bypass surgery, hemodialysis,
extracorporeal membrane oxygenation,
Percutaneous Transluminal Coronary
Angioplasty, cardiac catheterization,
and critical care. Over 15,000
HEMOCHRON systems have been sold
worldwide since its introduction.

The patented HEMOCHRON clot
detection mechanism consists of a
precision aligned magnet within a test
tube and a magnetic detector located
within the test well. When a test tube
is inserted into the well, the magnetic
detector senses a magnet within the
test tube as the tube slowly rotates.
When the clot begins to form, it causes
the magnet to lift within the tube.
Since the magnet has been displaced,
it is no longer sensed by the instru­ment’s magnetic detector. The instru

replacement for the more

-

ment gives an audible beep and
displays the coagulation time.

The HEMOCHRON system, which
includes the instrument plus test kits,
has developed over the years to offer
an expanding coagulation test menu.
At present, the whole blood activated
clotting time (ACT) test, activated
partial thromboplastin time (APTT)
test, prothrombin time (PT) test,
fibrinogen assay (FIB), thrombin time
(TT) test, heparin neutralizing
thrombin time (HNTT) test, high dose
thrombin time (HiTT), heparin
response test (HRT), protamine
response test (PRT), and protamine
dose assay (PDA) are available for the
HEMOCHRON. New tests are
constantly under development. For a
complete list of HEMOCHRON tests,
contact International Technidyne
Corporation.

4

F

eatures

■ Coagulation testing at bedside.

■ Uses fresh whole blood.

■ Test results within minutes.

■ Fully portable system.

■ Self-contained rechargeable nickel

cadmium batteries.

■ Automatic shut-off conserves
batteries.

Convenience Features of the Models 401 and 801

Automatic Shut-Off

If the “Start” button is depressed but
no test tube is inserted into the instru­ment within 60 seconds, the system
automatically sounds and displays a
FAULT 08 on the display screen. This
feature is designed to conserve the life
of the battery by preventing the instru­ment from running indefinitely.

■ “Select” button offering several test
result conversion and countdown
options.

■ Low battery indicator on the
display screen.

■ Automatically monitors internal
circuitry and reports problems to
display screen (see Trouble-shooting).

■ Microprocessor controlled for
enhanced reliability.

Select Options

1. Pre-Warm Option: Depressing the

“Select” button once will begin a 300
second (5 minute) pre-warming of the
test well. The display will countdown
this 300 second period and the alarm
will sound at 0 seconds. The test well
will warm up to 37 °C within 20
seconds and maintain that temperature
for five minutes.

Note: Some older HEMOCHRON
models use a 180 second Prewarm
feature instead of 300 seconds.

®

5

2. APTT Conversion Option: Before
beginning the fresh whole blood
OneStep APTT test by HEMOCHRON
(A103), depress the “Select” button two
times rapidly so that the letters APTT
appear on the display screen. Upon
completion of the APTT test and prior
to removing the APTT test tube from
the test well, the operator can obtain a
plasma equivalent value of the
HEMOCHRON OneStep APTT test
result by depressing the “Select” button
once. Pressing the “Select” button
again will return the HEMOCHRON
result and continual pushing of the
“Select” button toggles between the
two values as long as the test tube is
in the well. When the test tube is
removed, the instrument will only
display the HEMOCHRON whole
blood result.

Note: For differentiation, plasma
equivalent values are displayed with a
decimal point (123.45) while
HEMOCHRON whole blood results do
not have a decimal point (123).

will appear on the display screen
when a plasma equivalent value is
chosen and the actual result is outside
of the range of the HEMOCHRON test.

3.

PT Conversion Option: Before

beginning the fresh whole blood PT
test by HEMOCHRON (A201 or A203),
depress the “Select” button three times
rapidly so that the letters PT appear
on the display screen. Upon comple­tion of the PT test and prior to

removing the PT test tube from the test
well, two correlations can be obtained

for the HEMOCHRON PT result.

A plasma equivalent result with a
flashing
that the result is within the range of
the HEMOCHRON OneStep APTT but
outside of the range of a routine
plasma APTT test. Three dashes (---)

FAULT annunciator indicates

6

Depressing the “Select” button one
additional time will provide a plasma
equivalent PT value. Pressing the
button again will provide an INR value
(refer to PT package insert for an
explanation of INR). Pressing the
“Select” button one more time will
return the HEMOCHRON PT result and
continual pushing of the “Select”
button toggles between the three
values as long as the test tube is in the
well. When the test tube is removed,
the instrument will only display the
HEMOCHRON result.

Three dashes (---) will appear on the
display screen when a plasma equiva­lent or INR value is chosen and the
actual result is outside of the range of
both the HEMOCHRON and routine
plasma tests.

Note: For differentiation, plasma
equivalent values are displayed with a
decimal point (12.3), and are always
greater than 10.0, INR values are
displayed with a decimal point (1.2)
and are always less than 10.0,
HEMOCHRON results do not have a
decimal point (123).

Run On Shut Off

The HEMOCHRON instrument will
automatically shut itself off once the
timer exceeds 1500 seconds. This
feature conserves battery life if for any
reason an empty HEMOCHRON test
tube is inserted and the start button is
depressed. A HEMOCHRON test result
of greater than 1500 seconds should
be considered beyond clinical signifi­cance and the test should be immedi­ately repeated.

Self Monitoring

The Models 401 and 801 automatically
monitor internal circuitry and report
problems to the display screen.
Malfunctions will appear on the
display screen as an error code or
fault. For example, LO BAT will
appear on the display screen when the
battery is running low.

A complete list of FAULT codes with
an explanation can be found in the
TROUBLESHOOTING section of this
manual.

7

S

pecifications

HEMOCHRON Model 401 801

■ Number of Channels

■ Timing Range (seconds)

■ Incubation Temperature (°C)

■ Incubation Warm-Up Time (sec)

■ Operating Time on Full Battery

Charge, All Channels Constant

Run (hours)

■ Line Voltage (volts AC 50⁄60 Hz)

■ Power (watts)

■ Dimensions (w x d x h, cm)

■ Weight (kg)

1

0 - 1500

37 ± 0.5

14 - 20

4 - 6

120

(100, 220, 230 optional)

6

18 x 23 x 12.5

1.7

2

0 - 1500

37 ± 0.5

14 - 20

4 - 6

120

(100, 220, 230 optional)

11

25 x 28 x 15

2.6

8

O

perating Instructions

he HEMOCHRON coagulation
instrument can be operated
either on its self-contained

T

appropriate AC outlet. Routine
charging and discharging of the nickel
cadmium battery will improve its life­span. Coagulation tests can be
performed on the HEMOCHRON while
it is charging.

The HEMOCHRON is operated by
simply depressing the “Start” button to
begin the timer. The test well heater is
activated at the same time. Depress
the “Start” button twice if the instru­ment is asleep (blank screen). The
asleep mode is a conservation feature
during battery operation.

The proper operating procedure for
individual HEMOCHRON coagulation
tests can be found in the respective
package inserts. Common to all
HEMOCHRON test tubes is the magnet
and plastic center post. When a
HEMOCHRON test tube is inserted into
the test well the magnet positions itself
directly above the detector. To assure
this positioning, the operator should
rotate the test tube two full revolutions
clockwise while verifying that the
detector light is illuminated.

battery or plugged into the

Once a clot has been detected, a
beeping sound will be heard and the
clotting time will flash on the display
screen. This result will remain flashing
on the screen for 15 minutes.

Whenever a FAULT is on the
HEMOCHRON display screen and a
new test is desired, simply depress the
“Start” or “Select” button to begin a
new test.

9