O P E R AT O R ’ S M A N U A LM o d e l s 8 0 1 & 4 0 1

Table of ContentsSummary & 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

2

The HEMOCHRON® instru-ments (Models 401 and 801)are portable, battery oper-ated instruments designed to

perform an array of whole bloodcoagulation tests at any patient loca-tion. The Model 401 instrument hasone test well for single or sequentialtest determinations. The Model 801instrument has two individual testwells allowing for the simultaneousperformance of two coagulation tests.It is ideal for running the same test induplicate or for measuring twodifferent coagulation tests simultane-ously. The operation of both the 401and the 801 Models is the same.

The HEMOCHRON is manufacturedand quality assured by skilled tech-nical personnel using high quality testinstruments. Our Quality Assuranceteam uses rigorous standards to eval-uate and certify each machine. TheHEMOCHRON instrument complieswith CSA, L.A. County, and IEC stan-dards as well as many other state andcity codes.

Under routine operating conditions,the HEMOCHRON instrument willprovide uninterrupted trouble-freeservice. The HEMOCHRON is soldwith a Limited Warranty which ispublished in this manual.

Summary & Explanation

3

There are two pathways whichcomprise the overall coagula-tion cascade: The intrinsicand the extrinsic pathways.

There are twelve clotting factors orproteins involved in this cascadescheme. They are numbered I throughXIII, excluding factor VI which wasincorrectly used to label an extrinsicfactor.

The intrinsic pathway is so namedbecause all the proteins needed for theentire process are contained within theblood. The following clotting factorsare unique to this pathway: XII, XI,IX, and VIII. The extrinsic mechanismrequires a substance outside of theblood, tissue factor (Factor III), toinitiate the pathway. Only Factor VII isunique to this pathway. The extrinsicpathway of coagulation is much fasterthan the intrinsic.

Common to both the intrinsic andextrinsic pathways are Factor X,prothrombin, thrombin, fibrinogen andfibrin.

The HEMOCHRON system allows oneto conduct in vitro diagnostic coagula-tion tests at the patient bedside toensure accurate assessment of patienthemostasis.

Principle of the Procedure

4

The HEMOCHRON instrumentwas introduced commerciallyin 1969 as a convenientreplacement for the more

time-consuming and subjective Lee-White and manual activated clottingtime procedures. The Models 401 and801 provide many features for ease ofuse and reliability.

The HEMOCHRON system has enjoyedwidespread use during cardiopul-monary bypass surgery, hemodialysis,extracorporeal membrane oxygenation,Percutaneous Transluminal CoronaryAngioplasty, cardiac catheterization,and critical care. Over 15,000HEMOCHRON systems have been soldworldwide since its introduction.

The patented HEMOCHRON clotdetection mechanism consists of aprecision aligned magnet within a testtube and a magnetic detector locatedwithin the test well. When a test tubeis inserted into the well, the magneticdetector senses a magnet within thetest tube as the tube slowly rotates.When the clot begins to form, it causesthe magnet to lift within the tube.Since the magnet has been displaced,it is no longer sensed by the instru-ment’s magnetic detector. The instru-

ment gives an audible beep anddisplays the coagulation time.

The HEMOCHRON system, whichincludes the instrument plus test kits,has developed over the years to offeran expanding coagulation test menu.At present, the whole blood activatedclotting time (ACT) test, activatedpartial thromboplastin time (APTT)test, prothrombin time (PT) test,fibrinogen assay (FIB), thrombin time(TT) test, heparin neutralizingthrombin time (HNTT) test, high dosethrombin time (HiTT), heparinresponse test (HRT), protamineresponse test (PRT), and protaminedose assay (PDA) are available for theHEMOCHRON. New tests areconstantly under development. For acomplete list of HEMOCHRON tests,contact International TechnidyneCorporation.

Principle of Operation

5

Features

Automatic Shut-OffIf the “Start” button is depressed butno test tube is inserted into the instru-ment within 60 seconds, the systemautomatically sounds and displays aFAULT 08 on the display screen. Thisfeature is designed to conserve the lifeof the battery by preventing the instru-ment from running indefinitely.

Select Options1. Pre-Warm Option: Depressing the“Select” button once will begin a 300second (5 minute) pre-warming of thetest well. The display will countdownthis 300 second period and the alarmwill sound at 0 seconds. The test wellwill warm up to 37 °C within 20seconds and maintain that temperaturefor five minutes.

Note: Some older HEMOCHRON®

models use a 180 second Prewarmfeature instead of 300 seconds.

n Coagulation testing at bedside.

n Uses fresh whole blood.

n Test results within minutes.

n Fully portable system.

n Self-contained rechargeable nickelcadmium batteries.

n Automatic shut-off conservesbatteries.

n “Select” button offering several testresult conversion and countdownoptions.

n Low battery indicator on thedisplay screen.

n Automatically monitors internalcircuitry and reports problems todisplay screen (see Trouble-shooting).

n Microprocessor controlled forenhanced reliability.

Convenience Features of the Models 401 and 801

6

2. APTT Conversion Option: Beforebeginning the fresh whole bloodOneStep APTT test by HEMOCHRON(A103), depress the “Select” button twotimes rapidly so that the letters APTTappear on the display screen. Uponcompletion of the APTT test and priorto removing the APTT test tube fromthe test well, the operator can obtain aplasma equivalent value of theHEMOCHRON OneStep APTT testresult by depressing the “Select” buttononce. Pressing the “Select” buttonagain will return the HEMOCHRONresult and continual pushing of the“Select” button toggles between thetwo values as long as the test tube isin the well. When the test tube isremoved, the instrument will onlydisplay the HEMOCHRON wholeblood result.

Note: For differentiation, plasmaequivalent values are displayed with adecimal point (123.45) whileHEMOCHRON whole blood results donot have a decimal point (123).

A plasma equivalent result with aflashing FAULT annunciator indicatesthat the result is within the range ofthe HEMOCHRON OneStep APTT butoutside of the range of a routineplasma APTT test. Three dashes (---)

will appear on the display screenwhen a plasma equivalent value ischosen and the actual result is outsideof the range of the HEMOCHRON test.

3. PT Conversion Option: Beforebeginning the fresh whole blood PTtest by HEMOCHRON (A201 or A203),depress the “Select” button three timesrapidly so that the letters PT appearon the display screen. Upon comple-tion of the PT test and prior toremoving the PT test tube from the testwell, two correlations can be obtainedfor the HEMOCHRON PT result.

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Depressing the “Select” button oneadditional time will provide a plasmaequivalent PT value. Pressing thebutton again will provide an INR value(refer to PT package insert for anexplanation of INR). Pressing the“Select” button one more time willreturn the HEMOCHRON PT result andcontinual pushing of the “Select”button toggles between the threevalues as long as the test tube is in thewell. When the test tube is removed,the instrument will only display theHEMOCHRON result.

Three dashes (---) will appear on thedisplay screen when a plasma equiva-lent or INR value is chosen and theactual result is outside of the range ofboth the HEMOCHRON and routineplasma tests.

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

Run On Shut OffThe HEMOCHRON instrument willautomatically shut itself off once thetimer exceeds 1500 seconds. Thisfeature conserves battery life if for anyreason an empty HEMOCHRON testtube is inserted and the start button isdepressed. A HEMOCHRON test resultof greater than 1500 seconds shouldbe considered beyond clinical signifi-cance and the test should be immedi-ately repeated.

Self MonitoringThe Models 401 and 801 automaticallymonitor internal circuitry and reportproblems to the display screen.Malfunctions will appear on thedisplay screen as an error code orfault. For example, LO BAT willappear on the display screen when thebattery is running low.

A complete list of FAULT codes withan explanation can be found in theTROUBLESHOOTING section of thismanual.

8

Specifications

n Number of Channels

n Timing Range (seconds)

n Incubation Temperature (°C)

n Incubation Warm-Up Time (sec)

n Operating Time on Full BatteryCharge, All Channels ConstantRun (hours)

n Line Voltage (volts AC 50⁄60 Hz)

n Power (watts)

n Dimensions (w x d x h, cm)

n 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

HEMOCHRON Model 401 801

9

Operating Instructions

The HEMOCHRON coagulationinstrument can be operatedeither on its self-containedbattery or plugged into the

appropriate AC outlet. Routinecharging and discharging of the nickelcadmium battery will improve its life-span. Coagulation tests can beperformed on the HEMOCHRON whileit is charging.

The HEMOCHRON is operated bysimply depressing the “Start” button tobegin the timer. The test well heater isactivated at the same time. Depressthe “Start” button twice if the instru-ment is asleep (blank screen). Theasleep mode is a conservation featureduring battery operation.

The proper operating procedure forindividual HEMOCHRON coagulationtests can be found in the respectivepackage inserts. Common to allHEMOCHRON test tubes is the magnetand plastic center post. When aHEMOCHRON test tube is inserted intothe test well the magnet positions itselfdirectly above the detector. To assurethis positioning, the operator shouldrotate the test tube two full revolutionsclockwise while verifying that thedetector light is illuminated.

Once a clot has been detected, abeeping sound will be heard and theclotting time will flash on the displayscreen. This result will remain flashingon the screen for 15 minutes.

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

10

OperatingCautions & Limitations

The instrument should beplugged into the proper ACoutlet when not in use tomaintain the battery power

level. To unplug the instrument, firmlygrasp the plug and pull. DO NOTremove the plug from the outlet bypulling on the cord.

DO NOT force test tubes into the testwell. If resistance to insertion or rota-tion is encountered, gently remove thetest tube and examine the test well.Remove any obstruction beforeattempting further use of the instru-ment (see Service and Maintenance.)

DO NOT use excessive force indepressing the “Start” or “Select” button.

DO NOT expose the HEMOCHRONinstrument to extremes in temperature.Such exposure may affect all types ofsolid state instrumentation.

DO NOT drop the HEMOCHRONinstrument.

As with all microprocessor controlledinstrumentation, exposure to staticelectrical charges should be minimized.

Always plug the instrument into aproperly grounded, three prongedreceptacle. Do not use non-groundingadaptors.

HEMOCHRON instruments aredesigned for use only withHEMOCHRON coagulation test tubes.Other commercially available bloodcollection test tubes or culture tubeslack material and components neces-sary for clot detection inHEMOCHRON instruments.

In a properly maintained and operatedHEMOCHRON instrument, the accu-racy and precision of test results arelargely dependent upon the quality ofthe blood specimen used for the test.Factors such as specimen contamina-tion, inappropriate technique, or largetemperature variations will adverselyaffect most coagulation tests.

HEMOCHRON test results shouldalways be scrutinized in light of aspecific patient’s condition or anticoag-ulant therapy. Any HEMOCHRON testresult exhibiting inconsistency shouldbe repeated or supplemented withadditional test procedures.

HEMOCHRON test results greater than1500 seconds should be consideredbeyond clinical significance and thetest should be immediately repeated.All guidelines pertaining to thehandling of fresh whole human blood,such as CDC guidelines, should bestrictly adhered to when operating theHEMOCHRON instrument.

Used HEMOCHRON test tubes shouldbe considered contaminated. Theyshould be handled according to indi-vidual institutional policies concerningbody fluids and the disposal ofcontaminated materials.

It should be noted that HEMOCHRONequipment is not rated for use inexplosion-proof areas.

Use of this equipment other than inaccordance with the manufacturer’sguidelines is not recommended and isat the sole discretion of the institution.

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HEMOCHRON Cat Reagent Blood Mean Range UseTest No. Volume Normal (± 2 SD)

(sec) (sec)ACT CA510/ Diatomaceous 2.0 cc 132 105-167 Monitoring heparin during

FTCA510 Earth 160* 120-196 cardiovascular surgery.

ACT K-ACT/ Kaolin 2.0 cc 121 91-151 Monitoring heparin duringFTK-ACT 132* 110-154 cardiovascular surgery.

ACT P214/ Glass 0.4 cc 146 110-182 Monitoring heparin during P215 hemodialysis and ECMO.

APTT A103 Kaolin & platelet 2.0 cc 123 109-137 OneStep APTTFactor 3 substitute

PT A201 Thromboplastin 2.0 cc 61 50-72 Monitoring warfarin and ex-trinsic coagulation screening

PT A203 Thromboplastin 3.0 cc 61 50-72 Same as A201 exceptevacuated DirectDrawTM tube

FIB B101 Thrombin See Product Insert Quantitation of functionalfibrinogen in whole blood

TT A301 Thrombin 1.0 cc 46 38-54 Monitoring heparin and fibrinogen function in freshwhole blood.

HNTT A401 Thrombin 1.0 cc 44 31-56 Assessing fibrinogen functionProtamine in presence of heparin inSulfate fresh whole blood.

HiTT A501 Thrombin 1.5 cc 43 35-51 Monitoring heparinduring cardiovascular surgery.

QC CPL1/2 Non-Human Plasma See Product Insert Quality control ofHEMOCHRON ACT test tubes.

QC Q101 Non-Human Plasma See Product Insert Quality control of all non-ACTHEMOCHRON tests.

QC (FIB) B102 Human Plasma See Product Insert Quality Control ofHEMOCHRON FIBtest tubes

* Expected values for cardiovascular patients are different than for normal, healthy persons with CA510/FTCA510/K-ACT/FTK-ACT tubes.

Please refer to the instruction card and/or package insert included in each box of HEMOCHRON test tubes for detailson product use.

Performance (Expected Values)

13

Establishing a quality controlprogram is recommended forall in vitro diagnostic products.Routine quality control is

recommended for electronic diagnosticinstruments such as the HEMOCHRONto assure that no drift has occurred inthe calibration settings.TheHEMOCHRON instrument and coagu-lation tests should be qualitycontrolled using two levels of controland performed daily once per shift.Complete records of such qualitycontrol must be kept.

The temperature of the HEMOCHRONtest well can be verified externallywith the use of the HEMOCHRONTemperature Verification Test Tube(HE1001).

Routine quality control testing andtracking should be part of a compre-hensive Quality Assurance program.HEMOCHRON products for QualityControl are available to make routineQC convenient and affordable. Theseproducts are especially beneficialwhen an instrument problem issuspected. We recommend thatmultiple tests be run withHEMOCHRON control plasma beforesending an instrument to InternationalTechnidyne Corporation for service.

Detector SensitivityThe sensitivity of the clot detectionmechanism can be easily checked on adaily basis.

Procedure1. If the instrument is asleep (blankdisplay screen), depress the startbutton twice to begin the timer.

2. Insert an empty HEMOCHRON testtube(s), rotating it gently clockwisetwice, verifying illumination of thedetector light.

3. Wait 20 seconds, then slowly rotatethe entire instrument counterclockwiseonto its left side as viewed from thefront. At approximately 90 degreesfrom its normal horizontal position theinstrument should sound and flash thetime on the display screen.

If the instrument does not perform asdescribed, and QC values are consis-tently out-of-range, contact the ITCTechnical Service Department immedi-ately.

Quality Control

14

Test Well Temperature

Verified as follows:

1. Charge the HEMOCHRON

instrument battery fully.

2. Insert the HE1001 Temperature

Verification Tube into the

HEMOCHRON test well and depress

the START button. The green detector

light should illuminate and remain lit

for the entire temperature verification

procedure. Allow the instrument to

come to thermal equilibrium for at

least 10 minutes.

3. Without removing the verification

test tube from the test well, read the

temperature and record the results.

4. Repeat steps 2 and 3 for the second

test well. (Not applicable to Models

400/401)

An observed temperature deviation of

greater than ± 1 °C from 37 °C

suggests the necessity of instrument

recalibration. In this circumstance,

return the instrument to ITC with a

description of the fault.

Note: Before returning the instrument

for temperature recalibration, check

the calibration tube thermometer for

evidence of mercury column

separation and, if necessary, correct as

described in the Temperature

Verification Tube instruction sheet.

15

Service & Maintenance

Inspect and clean the test well andtest tube drive collar. Removeresidual dried blood or otherforeign matter using a 1:10 dilu-

tion of household bleach (sodiumhypochloride) with moistened cottonswabs.

Apply solution to clean and disinfectareas contaminated with residual driedblood. DO NOT use solvents orstrong cleaning solutions. They maydeform the instrument’s plastic components.

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Circuit Diagrams

Fig. 1. Schematic diagram HEMOCHRON Model 401

Fig. 2. Schematic diagram HEMOCHRON Model 801

Circuit Diagrams

17

18

Fig. 3. Schematic diagram HEMOCHRON Model 801

Fig. 4. Component Layout HEMOCHRON Model 401

Circuit Diagrams

19

Fig. 5. Component Layout HEMOCHRON Model 401

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Fig. 6. Component Layout HEMOCHRON Model 801

Fig. 7. Component Layout HEMOCHRON Model 801

Fig. 8. HEMOCHRON Models 401/801 Power Supply Schematic (115 V, AC)

Circuit Diagrams

21

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Fig. 8. HEMOCHRON Models 401/801 Power Supply Schematic (220 V, AC)

The Models 401 and 801 are almostcompletely self-monitoring. Theyautomatically monitor internal circuitryand report problems to the displayscreen. Malfunctions are assigned anerror code or fault and are detailed onthe instrument’s bottom label and inthe section on “Troubleshooting”.

HEMOCHRON instruments have afixed calibration system. AllHEMOCHRON instruments are fullycalibrated before shipping. Calibrationstatus is automatically monitored asnoted above. Any calibration error willbe signified by a FAULT 04 or 05 onthe LCD screen, a shift in clinicalresults and quality control (QC) values,or a failed detector sensitivity test.After diagnosing a calibration error,immediately contact ITC TechnicalService Department.

To optimize battery life, it is recom-mended that you run theHEMOCHRON on its battery duringthe day. Plug it into standard ACcurrent overnight to allow the batteries torecharge. The nickel cadmium batterycells work best when they are exer-cised in this manner.

A fully charged battery will operate theinstrument for four to six hours contin-uously or for approximately eight totwelve hours of clinical use.

The low battery indicator will appearon the display screen to alert youwhen the battery is running low. Atthat point, the instrument still hasapproximately one hour of batterytime left to perform coagulationtesting. Once this message appears,plug the instrument in at the earliestpossible convenience.

The POWER light should always beilluminated when the instrument isplugged into AC current. TheCHARGE light will only illuminateduring the rapid charge mode whichoccurs when the batteries are substan-tially depleted. Otherwise the CHARGElight will not illuminate and a tricklecharge will be given to the batteries.

When the batteries are drained to thepoint that valid testing cannot beperformed, the instrument will displayFAULT 06 (see Troubleshooting). Atthis point, the instrument must beplugged in for operation andrecharging. Whether or not the instru-ment’s batteries are functional, youwill not be inconvenienced by down-time because you may continue to runtests while the instrument is pluggedinto the AC outlet.

Service & Maintenance (cont.)

23

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Troubleshooting

Observation Possible CauseA. Long Clotting Times • Too much heparin

• Incubator temperature out of range• Incubator circuit or test well malfunction• Test tube does not rotate

B. Short Clotting Times • Tubes not mixed properly• Tubes not turned twice after green light comes on• Battery may be discharged

C. Battery Will Not Charge • Fuse(s) blown• Bad cell in battery• Charging circuit malfunction• Defective line cord or plug

D. Segments Missing • LCD counters exhibiting missing in Counter segments should be returned to the manufacturer

for replacement. The complete instrumentserial number must accompany such returns

E. Green Light Stays on Even • Press reset button. If problem persists, When the Tube is Removed contact ITC Technical Service Department

F. Green Detector Light • Tubes not mixed properlyDoes Not Illuminate • Tubes not rotated twice after insertion

into test well• Detector sensitivity error. Perform detector

sensitivity test. If problem persists, contact ITCTechnical Service Department

G. Tube Does Not Rotate • Motor physically damaged (this usually occurswhen an instrument has been dropped)

• Motor pulley is stripped on the motor shaft• Wires to motor are broken or disconnected• Test well and nameplate are misaligned

H. Unit Does Not Start When • Battery discharged Button is Pushed • Fuses blown

• Push reset button twice

Before attempting repairs, perform a careful inspection of the instrument. Avisual examination can frequently pinpoint the defect, especially if the unithas been dropped. Get a description of the malfunction and confirm it by

running your own test using an empty HEMOCHRON test tube.

Fault Definition Action

01 Test well temperature Send to ITC for correctionbelow acceptable level

02 Test well temperature Send to ITC for correctionabove acceptable level

03 Automatic run-on shut-off Repeat test being performed.Timer exceeded 1500 seconds If no test being run, no act-

ion is necessary

04 Clot detection sensitivity Depress reset button in rearnot set cord compartment. If FAULT

persists, contact ITC TechnicalService Department

05 Bias current calibration Contact ITC Technical Serviceerror Department

06 Battery error Charge battery for 12 hours.If FAULT persists, replacebattery

07 Internal diagnostics error Depress reset button foundin recessed electrical cordholder. If FAULT persists,contact ITC Technical Service department.

08 Automatic shut-off No action necessary

“###” Fault A flashing test result with the “Fault” label indicates the removal of a HEMOCHRON test tube prior to clot detection.

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Electronic components used inthe HEMOCHRON arecommercially available. If areplacement is required, it

may be purchased from your localHEMOCHRON distributor. Mechanicalcomponents and battery packs areavailable from International

Technidyne Corporation. The parts listincludes the stock number of eachavailable part. This stock number,together with the description of thepart, and the model and serialnumbers of the instrument, should beincluded with your order.

Replacement Parts

HEMOCHRON Model 401 and Model 801 (110 V and 100 V)

Part No. Description

HE1A Test Well Assembly

HE2-1 Circuit Board (Model 401)

HE2-2 Circuit Board (Model 801)

HE4A Motor

HE5-3 Battery Pack (Model 401)

HE5-4 Battery Pack (Model 801)

HE6-3 Transformer (Model 401 and Model 801)

HE8-7 LED - Green

HE8-9 LED - Amber

HE10-1 Fuse (F1), 1 amp AGC

HE11-1 Fuse (F2) 3/16 amp slow blow (Model 401 and 801)

HE11-6A Fuse Holder

HE12-401 Drive Kit (Model 401) includes:2 HE12-13 HE12-2A2 HE12-52 HE12-92 HE12-10A

HEMOCHRON Model 401 and Model 801 (110 V and 100 V)

Part No. Description

HE12-801 Drive Kit (Model 801) includes:2 HE12-13 HE12-2A2 HE12-52 HE12-92 HE12-10A

HE12-1 Motor Drive Pulley

HE12-2A Idler Pulley (large)

HE12-5A Drive Belt (Model 401 and Model 801)

HE12-9 Name Plate Drive Bushing

HE12-10A Test Tube Drive Pull/Collar

HE16-5 Name Plate (Model 401)

HE16-6 Name Plate (Model 801)

HE17 Reset Button

Parts Exclusive to 220 V Model 401 and Model 801

HE6-4A Transformer

(Model 401 and Model 801)

HE11-7A Fuse Holder

HE11-5A Fuse (F2) 100 ma (5mm x 20mm) slow blow(Model 401 and Model 801)

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Bergqvist D, Arborelius M, Fredin H, HellekantC, Modig J: Venous thrombosis and pulmonaryembolism. In: Renck H (editor): Bleeding andThrombotic Disorders in the Surgical Patient.Appleton and Lange/Mediglobe, 86-100, 1988.

Bull BS, Korpman RA, Huse WM, Briggs BD:Heparin therapy during extracorporeal circula-tion: I. Problems inherent in existing protocols.J Thorac Cardiovasc Surg 69:674-684, 1975.

Doty DB, Knott HW, Hoyt JL, Koepke JA: Heparindose for accurate anticoagulation in cardiacsurgery. J Cardiovasc Surg 20:597-604, 1979.

Esposito RA, Culliford AT, Colvin SB, Thomas SJ,Lackner H, Spencer FC: The role of the acti-vated clotting time in heparin administration andneutralization for cardiopulmonary bypass. JThorac Cardiovasc Surg 85:174-185, 1983.

Gambino R: Monitoring heparin therapy. LabReport for Physicians 4:17-20, 1982.

Hattersley P: Activated coagulation time ofwhole blood. JAMA 136:436, 1966.

Hattersley PG: Heparin anticoagulation. In:Koepke JA (editor): Laboratory Hematology.Churchill Livingstone, 789-818, 1984.

Hill JD, Dontigny L, deLaval M, Mielke CH: Asimple method of heparin management duringprolonged extracorporeal circulation. AnnThorac Surg 17:129-134, 1974.

LaDuca FM, Thompson S, Larson K:Neutralization of heparin using a protamine titra-tion assay and the activated clotting time test.AmSECT Proc 19:358-364, 1987.

LaDuca RM, Thompson SJ, Reitz BA:Optimization of the protamine dose to neutralizeheparin: Use of a titration assay to individualizedosage requirements. Submitted for publication.

Lee RI, White PD: A clinical study of the coagu-lation time of blood. Am J Med Sci 145:495-503,1913.

Lindsay RM. Practical use of anticoagulants. In:Drukker W, Parsons FW, Maher JF (editors):Replacement of Renal Function by Dialysis.Martinus Nijhoff Publishers, 201-222, 1983.

Miale JB: Laboratory Medicine - Hematology,Fourth Edition. The Mosby Company, St. Louis,Missouri, p 1267, 1972.

Miller DW Jr., Binford JM, Hessel EA: Results ofa survey of the professional activities of 811cardiopulmonary perfusionists. J ThoracCardiovasc Surg 83:385-389, 1982.

National Institutes of Health ConsensusDevelopment Conference Statement: Preventionof venous thrombosis and pulmonary embolism.1986.

Ogilby JD, Kopelman HA, Klein LW, Agarwal JB:Adequate heparinization during PTCA:Assessment using activated clotting time. JACC11:237A, 1988.

Rivard DC, Thompson SJ: Demonstration ofheparin reversal with protamine administrationusing an automated protamine dose assay:comparison of two methods. AmSECT Proc20:63-64, 1988.

Sanders PW, Curtis JJ: Management of anticoag-ulation for hemodialysis, In: Nissenson ARE,Fine RN (editors): Dialysis Therapy. The C.V.Mosby Company, 39-41, 1986.

Schriever HG, Epstein SE, Mintz MD: Statisticalcorrelation and heparin sensitivity of activatedpartial thromboplastin time, whole blood coagu-lation time, and an automated coagulation time.Am J Clin Path 60:323-329, 1973.

Scott JA, Berenstein A, Blumenthal D: Use ofthe activated coagulation time as a measure ofanticoagulation during interventional proce-dures. Radiology 158:849-850, 1986.

Transfustion alert: Indications for the use of redblood cells, platelets, and fresh frozen plasma.NIH Publication No. 89-2794a, May 1989.

Suggested Reading

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CE Marking and Related Safety StandardsThe HEMOCHRON® instrument complies with the following safety standard regulations:

EN55011 (Mar 1991) Limits and Methods of Measurement of Ratio Disturbance Characteristics of Industrial, Scientific and Medical (ISM) Radio Frequency Equipment

EN50082-1 (Jan 1992) Electromagnetic compatibility - Generic Immunity Standard, Part 1: Residential, Commercial and Light Industry.

EN60601-1-2 (Apr 1993) Medical Electrical Equipment: Part 1: General Requirement for Safety. Part 2: Collateral Standard: Electromagnetic Compatibility - Requirements and Tests

IEC 801-2 (1991) Electromagnetic Compatibility for Industrial-Process Measurement and Control EquipmentPart 2: Electrostatic Discharge Requirement

IEC 801-3 (1984) Electromagnetic Compatibility for Industrial-Process Measurement and Control EquipmentPart 3: Radiated Electromagnetic Field Requirement

IEC 801-4 (1988) Electromagnetic Compatibility for Industrial-Process Measurement and Control EquipmentPart 4: Electrical Fast Transient/Burst Requirements

IEC 801-5 (Draft, 1993) Electromagnetic Compatibility for Industrial-Process Measurement and Control EquipmentPart 5: Surge Immunity Requirements

EMC Directive 89/336 EECAll the relevant documentation is kept and can be requested at the following address:

ITC UKThe Hilger Site, WestwoodRamsgate Road, MargateKent, CT94JLEnglandTel: (01843) 232434Fax: (01843) 232-142

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HD2525 R3 8/99