ROTEM_Analysis_delta_platelet_EN

Guide ROTEM

Analysis - 09-2016 2

Introduction

In this text, the basis of ROTEM

analysis is described together with its

use during the management of acute bleeding.

The management of acute bleeding is a complex challenge. Little that is

done in this area is fulfilling the hard criteria of evidence based medicine.

The recommendations in this compendium are based on the experience

of the authors and on the discussion with centres, which use the

ROTEM

system in clinical routine. However, these recommendations

have not yet been prospectively validated.

Causes of Haemostasis Disorders

Haemostasis disorders can have several causes. Rather chronic

processes (such as comorbidities of the haemostasis-related organs

liver - kidney - bone marrow) or hereditary diseases can be differentiated

from more acute alterations due to trauma, haemodilution and the

current treatment. The resulting alterations affect the plasmatic

coagulation factors, platelets and the fibrinolytic system.

Bleeding most frequently occurs during and after surgical interventions

or traumas, i.e. in situations where trauma and secondary alterations

(e.g. due to haemodilution) are added to the disposition of the patient.

During such complex haemostasis disorders, the clinical significance of

the routine parameters PT, aPTT and platelet count is rather weak. This

leads to the interest in laboratory methods, which better reflect

haemostasis during these complex processes.

A. Calatzis, W. Schramm, M. Spannagl. Management of Bleeding in Surgery and

Intensive Care. I. Scharrer / W. Schramm (Ed.), 31 st Hemophilia Symposium

Hamburg 2000, Springer Verlag Berlin Heidelberg 2002.

3 Guide ROTEM

Analysis - 09-2016

Alterations of haemostatic causes

Trauma and coagulopathy as a cause of bleeding

Guide ROTEM

Analysis - 09-2016 4

Thromboelastometry

Dr. Andreas Calatzis, Prof. Dr. Michael Spannagl, Dr. Matthias Vorweg

Targeted Treatment of Bleeding Events

During acute bleeding, a multitude of different therapeutic options are at

disposition to the physician. The difficulty is to choose the right

medication at the right time and to evaluate how much, respectively how

often, the respective therapeutic option has to be applied. Typically, only

the

right therapy will stop the bleeding. It will be of little use to the patient,

if he is transfused with FFP while he is bleeding because of

thrombocytopenia or hyperfibrinolysis. Although this sounds self-

evident, in the clinical everyday routine, a "blind" therapy is often applied.

This means that different medication and blood products are

administered consecutively until the bleeding stops. If the cause of the

bleeding is not the most obvious, unnecessary medication and blood

products are administered. Thus, unnecessary costs are created and the

patient is exposed to potentially harmful preparations.

TEG / ROTEM

- History

Thrombelastography was developed during world war II by professor H.

Hartert in Heidelberg. Following a quite broad application in the 50's and

60's, the interest in TEG decreased in the 70's. In the 80's it came to a

renaissance of TEG, especially in the United States, because of the

application in anaesthesia for the management of acute bleeding. The

ROTEM

system is an enhancement of thrombelastography and was

developed during 1995-1997 in Munich. The instrument includes four

measurement channels for simultaneous determinations, an integrated

computer for automatic analysis and an electronic pipette for interactive

test operation.

Note: The term "TEG" was introduced by Hartert in his first publication

on thrombelastography in 1948. Surprisingly, in 1993, an American

company obtained a trade mark on this term in the USA, after 45 years

of its use as a generic medical term. In order to achieve a global

uniformity of the name, the manufacturer of the ROTEM

system (Tem

Innovations GmbH, Munich) has renamed its instrument from "ROTEG"

into "ROTEM" and the tests accordingly from "EXTEG" into "EXTEM",

"INTEG" into "INTEM" etc. in 2003. "TEM" thereby stands for

"thromboelastometry" (analogous to the term "thromboelastography"),

thus the plotting of the clot firmness.

5 Guide ROTEM

Analysis - 09-2016

Bleeding: Therapeutical options

ROTEM

Thromboelastometry system

• 4 channels for simultaneous assays

• Automated testing in ROTEM

sigma, standardized

electronic pipetting for ROTEM

delta

ROTEM

delta ROTEM

sigma

Guide ROTEM

Analysis - 09-2016 6

ROTEM

thromboelastometry detection method

In the ROTEM

system, the sample is placed into a cuvette and a

cylindrical pin is immersed. Between pin and cuvette remains a gap of 1

mm, which is bridged by the blood or the blood clot. The pin is rotated by

a spring alternating to the right and the left. As long as the blood is liquid,

this movement is unrestricted. As soon as the blood clots, the clot

restricts the rotation of the pin increasingly with rising clot firmness.

Thus, the rotation of the pin is inverse proportional to the clot firmness.

It is detected optically. An integrated computer calculates the ROTEM

curve as well as its numerical parameters.

In contrast, in the TEG according to Hartert, the cuvette is rotated. The

pin is suspended freely from a thin wire and does not move until a clot

forms. Because of this free suspension of the pin, the TEG according to

Hartert is quite susceptible to vibration and mechanical shocks.

Due to the mechanical measurement principle of ROTEM

analysis,

blood or plasma can be analysed likewise. This is advantageous for the

point-of-care application, as centrifugation of the sample is omitted

there.

The parameters of ROTEM

thromboelastometry analysis

For historical reasons, the curve is plotted two-sided, expressed in mm.

CT (clotting time): time from start of the measurement until

initiation of clotting

 initiation of clotting, thrombin

formation, start of clot polymerisation

CFT (clot formation time): time from initiation of clotting until a clot

firmness of 20 mm is detected

 fibrin polymerisation,

stabilisation of the clot with thrombocytes and FXIII

MCF

(maximum clot firmness): firmness of the clot

 increasing

stabilisation of the clot by the polymerised fibrin,

thrombocytes as well as FXIII

ML (maximum lysis): reduction of clot firmness after MCF in

relation to MCF

 stability of the clot (ML< 15%) or

fibrinolysis (ML > 15% within 1h)

7 Guide ROTEM

Analysis - 09-2016

ROTEM

thromboelastometry detection method

ROTEM

thromboelastometry parameters and scaling

Guide ROTEM

Analysis - 09-2016 8

ROTEM

thromboelastometry tests

In the past, “the thrombelastogram“ was analysed using freshly drawn

blood without the addition of any citrate / calcium and without any

activators. The measurements were therefore very time consuming (45 -

60 min.) and quite unspecific.

With the ROTEM

, activated determinations are usually performed. As

in the laboratory coagulation analysis, various activators or inhibitors are

added to the sample, in order to represent different processes of

haemostasis. For the analysis, citrated blood is usually used.

In EXTEM, coagulation is activated by a small amount of tissue

thromboplastin (tissue factor). This typically leads to the initiation of clot

formation within 70 seconds. Thus, clot formation can be assessed

within 10 minutes.

In INTEM, coagulation is activated via the contact phase (as in the aPTT

and ACT). The INTEM is therefore sensitive for factor deficiencies of the

intrinsic system (e.g. FVIII) and for the presence of heparin in the

sample.

In FIBTEM, coagulation is activated as in EXTEM. By the addition of

cytochalasin D, the thrombocytes are blocked. The resulting clot is

therefore only depending on fibrin formation and fibrin polymerisation.

In APTEM, coagulation is also activated as in EXTEM. By the addition of

aprotinin or tranexamic acid in the reagent, fibrinolytic processes are

inhibited in vitro. The comparison of EXTEM and APTEM allows for a

rapid detection of fibrinolysis. Furthermore, APTEM enables the

estimation if an antifibrinolytic therapy alone normalises the coagulation

or if additional measures have to be taken (e.g. administration of

fibrinogen).

In HEPTEM, coagulation is activated as in INTEM. The addition of

heparinase in the reagent degrades heparin present in the sample and

therefore allows the ROTEM

analysis in heparinised samples.

Reagent type Test name for each reagent type

Single Use EXTEM S FIBTEM S APTEM S INTEM S HEPTEM S

Liquid EXTEM (L) FIBTEM APTEM INTEM HEPTEM

Cartridge EXTEM C FIBTEM C APTEM C INTEM C HEPTEM C

9 Guide ROTEM

Analysis - 09-2016

ROTEM

thromboelastometry tests

EXTEM (L, S, C): activation of clot formation by

thromboplastin (tissue factor).

Assessment of factors VII, X, V, II, I, platelets,

fibrinolysis

INTEM (S, C): activation of clot formation via the

contact phase.

Assessment of factors XII, XI, IX, VIII, X, V, II, I,

platelets, fibrinolysis

FIBTEM (S, C): activation as in EXTEM with the

addition of cytochalasin D, a platelet blocking

substance. In the FIBTEM assay, fibrinogen

levels and fibrin polymerisation can be assessed

in a functional way.

APTEM (S, C): activation as in EXTEM with the

addition of aprotinin or tranexamic acid,

fibrinolysis inhibitors. In an assay comparing

APTEM to EXTEM, fulminant hyperfibrinolysis

can be recognised within 10-20 minutes.

HEPTEM (S, C): activation as in INTEM with the

addition of heparinase. Heparinase degrades

heparin. When HEPTEM results are compared

to INTEM, heparin related coagulation

disturbances can be specifically detected.

Guide ROTEM

Analysis - 09-2016 10

ROTEM

thromboelastometry expected values

On the opposite page, typical ROTEM

thromboelastometry values are

shown, which are found when healthy patients without coagulation

disorders are analysed. Depending on the examined population, these

values can vary (for example, when healthy younger persons are

assessed, lower MCF values are found). It is therefore recommended, at

introduction of ROTEM

, to analyse some patients without pathological

findings in order to establish respective 'local' reference ranges.

Interpretation of HEPTEM / APTEM / FIBTEM

In HEPTEM and APTEM, the comparison with INTEM respectively

EXTEM is important for the interpretation. A shortening of the clotting

time in HEPTEM as compared to INTEM indicates a heparin effect.

The ’spindle’ shape of the TEMogram in the EXTEM, INTEM or FIBTEM

assays gives an indication of fibrinolysis. The reversal back to a normal

TEMogram shape in the APTEM assay confirms the fibrinolysis and

allows to judge the patient‘s clot quality after an optional hyperfibrinolytic

treatment.

A reduced MCF in FIBTEM indicates a reduced fibrinogen level and / or

a clot polymerisation inhibition. Discrepancies between FIBTEM and the

fibrinogen determination in the laboratory are frequently found, as

FIBTEM is much more sensitive to clot polymerisation disorders than

conventional laboratory assays.

Classification of the ROTEM

results

The lower right table shows an orientating classification of the ROTEM

results based on our clinical experiences.

Depending on the situation and possible comorbidities of the patient,

different target ranges will be aimed for the MCF, respectively CFT.

During surgery, we typically aim for a MCF value of at least 40 mm and

a CFT of maximal 300 s. In persistent bleeding situations, an almost

normalisation of the ROTEM

findings will be aimed for.

Hyperfibrinolysis (lysis of the clot in vitro) is always pathological and can

be treated with an antifibrinolytic drug. Nevertheless, hyperfibrinolysis

can be self-limiting, which can be checked by repeated determinations

without any preceding therapy.

11 Guide ROTEM

Analysis - 09-2016

ROTEM

thromboelastometry reference ranges

(Lang et al. 2006 for ROTEM

delta, preliminary for ROTEM

sigma)

*Historical value

INTEM (S) / EXTEM (S) results - Clinical interpretation

MCF

MCF > 72 mm: enhanced haemostatic reserve

MCF 50-72 mm: normal range

MCF 46-49 mm: usually unimpaired haemostasis with reduced reserve

MCF 40-45 mm: bleeding risk

MCF 30-39 mm: high bleeding risk

MCF < 30 mm: usually no effective haemostasis

CFT

CFT 34-159 s: normal range

CFT 160-220 s: usually unimpaired haemostasis with reduced reserve

CFT 221-300 s: bleeding risk

CFT 301-400 s: high bleeding risk

CFT > 400 s: usually no effective haemostasis

Fibrinolysis

Lysis of the clot within 20 minutes (fulminant lysis): usually acute

bleeding. Lysis of the clot within 20 – 40 minutes: high bleeding risk.

Lysis of the clot after more than 40 minutes: frequently clinically

insignificant, may however raise to fulminant lysis.

Test

/ Parameter

(s)

CFT

(s)

A10

(mm)

MCF

(mm)

LI60

(%)

EXTEM (S) 38-79 34-159 43-65 50-72  85*

EXTEM C 50-80 46-149 43-63 55-72  94

INTEM (S) 100-240 30-110 44-66 50-71  85*

INTEM C 161-204 62-130 43-62 51-69  87

HEPTEM (S, C)

Comparison with INTEM (S,C). A better clot formation in HEPTEM (S,C) as

compared to INTEM (S,C) indicates the presence of heparin or heparin-like

anticoagulants in the sample.

APTEM (S, C)

Comparison with APTEM (S,C). A better clot formation in APTEM (S,C) as

compared to EXTEM (S,C) is a sign of hyperfibrinolysis.

FIBTEM (S) n.d. n.d. 7-23 9-25 n.d.

FIBTEM C n.d. n.d. 6-21 6-21  89

Guide ROTEM

Analysis - 09-2016 12

Assessment of the ROTEM

thromboelastometry analysis

The ROTEM

analysis covers the whole process of whole blood

coagulation, from the formation of the first fibrin strands over the

maximum firmness of the clot until its lysis.

The assessment of the ROTEM

analysis is carried out along the time

axis (from left to right): A disturbed activation of coagulation is indicated

by a prolonged clotting time. As causes, a factor deficiency or a heparin

effect have to be considered. The comparison of INTEM and HEPTEM

allows for a specific detection of a heparin effect.

An abnormal clot formation is indicated by a prolonged clot formation

time (CFT) and/or a reduced clot firmness (A10/MCF). The CFT is

thereby influenced stronger by a clot polymerisation disorder than the

MCF.

A prolonged CFT with at the same time normal A10/MCF indicates

therefore a polymerisation disorder, whereas a reduced A10/MCF with a

normal CFT rather indicates a deficiency of clottable substrate

(fibrinogen and/or platelets).

Fibrinolysis is detected by the lysis of the clot (ML > 15%) or by the

finding of a better clot formation (shorter CFT, greater MCF) in APTEM

(S,C) as compared to EXTEM (S,C). If in APTEM (S,C), with the

occurrence of the typical pattern of a hyperfibrinolysis (spindle shaped,

total lysis of the clot firmness) in EXTEM (S,C) (as in INTEM (S,C),

FIBTEM (S,C), HEPTEM (S,C)), the hyperfibrinolysis is not present, then

hyperfibrinolysis is confirmed.

Limitations

In the interpretation of ROTEM

analysis it is important to know and

consider the limitations of the method. The ROTEM

delta and sigma

tests are not sensitive to the effect of the platelet inhibitors Aspirin

clopidogrel and Reopro

(only in supra-therapeutic doses). In this

situation, ROTEM

platelet analysis should be performed. Also, the

effect of the von Willebrand factor is not detected. Furthermore, a normal

ROTEM

analysis does not exclude the anticoagulants Orgaran

pentasaccharide, low-molecular-weight heparin as well as oral

anticoagulants such as Warfarin

. For analysis of these factors, other

diagnostic tests have to be performed.

13 Guide ROTEM

Analysis - 09-2016

ROTEM

thromboelastometry: detection and therapy

Limitations of ROTEM

thromboelastometry

Platelet inhibitors:

• no detection of Aspirin

• no detection of clopidogrel/Plavix

• no detection of von Willebrand syndrome

• poor sensitivity to Reopro

Anticoagulants:

• poor sensitivity to low molecular weight heparin, Orgaran

and

pentasaccharide

• poor sensitivity to oral anticoagulants

(coumarins: Warfarin

, etc.)

Activation of coagulation

=> protamin, FFP of PCC

=> differentiation with HEPTEM

Clot formation

=> infusion of platelets and/or fibrinogen/

FFP

=> differentiation with FIBTEM

Fibrinolysis

=> infusion of antifibrinolytics

=> more rapid detection with the

combination of APTEM-EXTEM

Consequence:

• Combine with other methods (e.g. ROTEM

platelet

aggregation) where required.

• Consider limitations for interpretation!

Guide ROTEM

Analysis - 09-2016 14

Performance of ROTEM

thromboelastometry analysis

As in all diagnostic tests, correct pre-analytics and correct performance

of the assay are essential for meaningful results.

As ROTEM

is run directly with citrated whole blood, a specific sample

preparation is not necessary. “Correct sampling“ means: Complete filling

of the sampling tube (in order to ensure the correct citrate-blood ratio);

the assurance, during sampling from catheters, that no contamination

with heparin or other anticoagulants occurs; and the avoidance of

haemolysis during sampling (prevent excessive stasis, use of a needle

with sufficiently wide diameter). We typically aim for an analysis of the

sample within 2 hours from the sampling of the blood

(if required up to four hours). The analysis of samples that have been

transported by a tube system is usually possible. As a precaution this

should be verified (split the sample and analyse with/without transport by

the tube system).

The steps to be performed for ROTEM

delta analysis are shown on the

right. The test operation is generally simple - also for staff without any

laboratory experience. Nevertheless, a certain familiarisation period and

motivation are necessary.

The ROTEM

sigma offers a fully automated, cartridge based system.

The familiarisation is reduced to a minimum.

Apart from the correct performance of the analysis – as in every

laboratory test – the plausibility control of the analysis is important.

Measurements with irregular shapes (steep rise or fall of the clot

firmness, noised curves, and start of the clot formation in less than 20

seconds), generally accompanied by error messages, should be

repeated.

When using liquid reagents on the ROTEM

system, it has to be

controlled optically if the liquid was actually aspirated while pipetting the

liquids. A typical source of error is that the pipette tip has not been

immersed into the liquid.

Like any other in vitro diagnostic system, the ROTEM

system requires

quality control by performing tests with standardised quality control (QC)

materials. The ROTEM

standardised system controls ROTROL N and

ROTROL P are based upon human plasma and will show reaction

curves at two different levels.

15 Guide ROTEM

Analysis - 09-2016

Performing a ROTEM

delta test

1. Properly attach

2. Insert cup and bring

to position using the

MC rod

3. Select test, enter/

scan patient data

4. Pipetting steps are

displayed on the

screen

5. Pipetting and mixing

of reagents and blood

sample

6. Insert cup holder

in measurement

position

7. On screen display

of TEMograms and

numeric parameters

8. Discard used cup

and pin

Guide ROTEM

Analysis - 09-2016 16

Interpretation of ROTEM

thromboelastometry analysis:

examples performed on ROTEM

delta with liquid reagents

On each of the next pages, three typical combinations of ROTEM

tests

are shown. The figures are displayed exactly as on the screen of the

ROTEM

system. With each measurement you see the respective test

name above the parameters. In each case, the figures represent 1-4

measurements of one sample. The measurements are not commented

on the right hand page. This shall give the reader the opportunity to

reflect the interpretation and therapy on his own.

Sample 1:

normal coagulation in the ROTEM

. EXTEM and INTEM show a normal

coagulation activation (CT normal), normal clot formation (CFT and MCF

normal) as well as a stable clot (no lysis of the clot in EXTEM, INTEM or

FIBTEM). The FIBTEM shows a normal fibrin clot.

Should the patient bleed clinically, the following causes have to be

considered: surgical cause of bleeding, Warfarin

therapy (low

sensitivity of EXTEM), Aspirin

, clopidogrel, von Willebrand syndrome

(for these drugs respectively pathologies ROTEM

delta and ROTEM

sigma tests show low sensitivity) as well as errors (e.g. sample mix-up).

17 Guide ROTEM

Analysis - 09-2016

Sample 2:

strongly prolonged clot formation time (CFT), strongly reduced clot

firmness (MCF) in EXTEM and INTEM show a strongly reduced

haemostatic capacity. The zero line in FIBTEM (no clotting) shows a

strongly reduced fibrinogen level and/or a disturbed fibrin

polymerisation. The first line treatment would be a highly dosed

administration of fibrinogen concentrate (2-6 g) or cryoprecipitate or a

larger amount of FFP (5-15 units). In cases of massive bleeding it would

be considered to concomitantly transfuse platelets.

Sample 3:

fibrinolysis (lysis of the clot in EXTEM, INTEM and FIBTEM) with an at

the same time borderline acceptability of MCF (MCF = 47 mm in

APTEM). Good fibrin clot in FIBTEM. Therapy would be an

antifibrinolytic drug. In cases of persisting bleeding, administration of

platelets would be suggested (for correction of the clot formation).

Guide ROTEM

Analysis - 09-2016 18

Sample 4:

borderline acceptability of clot firmness in INTEM and EXTEM. No

evidence of a hyperfibrinolysis. Normal fibrin clot in FIBTEM.

Comparable results are sometimes found with or without clinical

bleeding. First line therapy for improvement of clot formation would be

the administration of platelets. In any case, the patient has typically only

a poor haemostatic reserve at further haemodilution. Depending on the

situation (further surgical blood loss expected or not), a correction of

coagulation can be considered also without the occurrence of acute

bleeding.

Sample 5:

just abnormal / still normal clot formation in EXTEM and INTEM

(depending on the investigated reference population). The relatively high

clot firmness in FIBTEM (MCF = 37 mm) can lead to a normal whole

blood coagulation, also when thrombocytopenia is present. Therefore a

blood count should be determined in this situation (in order to assess

platelet count directly), and the coagulation in course of further

haemodilution should be controlled. Patients with high fibrinogen levels

usually tolerate a thrombocytopenia better than patients with normal or

reduced fibrinogen levels. Nevertheless, it is reasonable to keep an eye

on the blood count in these situations.

19 Guide ROTEM

Analysis - 09-2016

Sample 6:

combined haemostasis disorder. We see a hyperfibrinolysis (lysis of the

clot in EXTEM and INTEM), a prolonged CT in INTEM (heparin effect),

a strongly reduced clot firmness in APTEM (indicates a disturbance of

clot formation exceeding fibrinolysis) as well as a zero line (no clotting)

in FIBTEM (reduced fibrinogen and / or polymerisation disorder). This

result is not compatible with clinically normal haemostasis and requires

a rapid combined treatment: an antifibrinolytic drug for the treatment of

the hyperfibrinolysis, fibrinogen or FFP (large doses) for improvement of

the clot formation. In cases of such an insufficient clot formation, a

simultaneous platelet administration is also recommended (it would

however also be possible to give fibrinogen or FFP first and then check

the clot formation).

Guide ROTEM

Analysis - 09-2016 20

Sample 7:

detection of heparin (strongly prolonged CT in INTEM), corrected in

HEPTEM. In this situation one can wait (short half-life of heparin) or

neutralize the heparin using protamin (during acute bleeding). As seen

in HEPTEM, the clot firmness is reduced but still within an acceptable

range. Therefore one would usually neutralise the heparin first and see

if bleeding stops. If bleeding continues, administration of FFP, fibrinogen

or platelets might be necessary.

Sample 8:

erroneous measurement. This error can occur if the pin was not attached

completely onto the axis or the cup was not inserted sufficiently into the

cup holder. Cup and pin will be in contact with each other when the cup

holder is put in place. An error message appears, the measurement

should be stopped and started again.

21 Guide ROTEM

Analysis - 09-2016

Sample 9:

erroneous measurement. After MCF is reached, there is a further

increase of the clot firmness after some time. An error message, which

is caused by a drying of the sample, appears. A falsely-high MCF is

detected. In this case it should be checked whether the cup holder is

dirty at its upper surface and the corresponding area on the lower side

of the instrument should be cleaned. For this, a moist cloth should be

used and no sprays should be applied on the instrument as this could

lead to damage of the ball bearing. Should there be no contamination,

the cup holder or its plastic clip might be damaged and need

replacement.

Note: test results should represent only one aspect of any

therapeutic decision. Always the situation (bleeding yes - no), the

plausibility of the findings, patient history, comorbidities as well as

the expected (surgical) course of the case has to be taken into

account. Further tests may be performed if required (PT,

antithrombin, d-dimer, platelet function tests, blood count).

Guide ROTEM

Analysis - 09-2016 22

Clinical cases (studied with the ROTEM

liquid reagents):

On the following pages, clinical cases with the corresponding ROTEM

analyses are shown.

Case 1:

On the right page, 3 coagulation conditions during a multiple trauma

treatment are shown.

The first test time point shows fibrinolysis in EXTEM and INTEM. In

APTEM, no lysis appears due to addition of aprotinin in the reagent.

In APTEM, we see an abnormal but still acceptable clot firmness.

The therapeutic consequence was the administration of an

antifibrinolytic drug.

23 Guide ROTEM

Analysis - 09-2016

The second test time point shows the therapeutic success of the

antifibrinolytic drug administration (no lysis detected any more).

Nevertheless we see a strongly reduced clot firmness (MCF) as well as

a strongly prolonged clot formation time (CFT), which was the indication

for platelet and FFP administration.

The third test time point represents a normal, whole blood coagulation

towards the end of the surgery.

Guide ROTEM

Analysis - 09-2016 24

Case 2:

The second case example shows the therapy control with ROTEM

in a

situation in which initially therapy was guided on the basis of the routine

laboratory.

We thank Dr. Georg Pfanner, consultant anaesthetist at the Department

of Anaesthesia and Critical Care of the Academic Teaching Hospital

Feldkirch, Austria ([email protected]), for recording and providing

us with this case.

The situation: a patient with a multiple trauma is admitted to the hospital.

The patient has been already notably diluted (4 l of infusions).

The initial laboratory findings show a prolonged PT (factor deficiency), a

low fibrinogen, low antithrombin and a platelet count of 101.000/l.

On the basis of these results, fibrinogen, PCC and antithrombin were

administered. Because of a strongly increased D-dimer result, the

question of an antifibrinolytic therapy aroused.

In the persistent bleeding situation, a control with ROTEM

is carried

out. The results show a strongly abnormal clot formation (clot firmness

reduced, clot formation time prolonged), in spite of the initial therapy.

Despite the initially acceptable platelet count, there is no sufficient whole

blood coagulation.

After therapy with fibrinogen, platelets and PCC, clinically a clear

improvement of the clinical haemostasis was found together with a

normalised whole blood coagulation in ROTEM

25 Guide ROTEM

Analysis - 09-2016

Initial situation:

Polytrauma => GCS 3, suspected thorax-trauma, pelvic fracture

Severe bleeding from nose, mouth, multiple wounds in the neck

Infusion therapy: HES 1000 ml, cristalloid 3500 ml

Laboratory results in hospital (65 min. after arrival):

PT 40%, aPTT 55.8s, fibrinogen 0.87 g/l, AT 49%, d-dimer 39.7,

thrombocytes 101.000/l

Assessment: reduced fibrinogen level, factor levels low, antithrombin

lowered (similar to PT), platelet count still sufficient. Fibrinolysis

suspected (very high d-dimer).

Initial therapy: 3 g fibrinogen (Haemocomplettan®), 4000 units PPSB,

3000 units antithrombin

Guide ROTEM

Analysis - 09-2016 26

Differential diagnosis and therapy: thromboelastometry

algorithms

On the right hand page, the differential diagnostic and therapeutic

algorithm used in the Clinic Cologne-Merheim is shown (Reference:

Vorweg M, Hartmann B, Knuttgen D, Jahn MC, Doehn M. Management

of fulminant fibrinolysis during abdominal aortic surgery. J Cardiothorac

Vasc Anesth. 2001 Dec;15(6):764-7).

This algorithm shows how coagulation activation, clot formation and

fibrinolysis are assessed starting from EXTEM and INTEM as screening

tests. If no coagulopathy is found, other reasons for the bleeding are

evaluated: a surgical bleeding or coagulopathy which is not detected by

ROTEM

analysis (Aspirin

, von Willebrand factor, warfarin?).

The combination of EXTEM and APTEM allows for a rapid detection of

a fulminant fibrinolysis.

The cause for a reduced clot firmness can be differentiated by

performing a FIBTEM test.

With the HEPTEM test, a prolonged clotting time in INTEM can be

differentiated.

Thus, many causes of acute haemostasis disorders can be recognised

rapidly and in consequence be treated appropriately.

Acknowledgement

The authors, Dr. Calatzis, Dr. Spannagl and Dr. Vorweg, would like to

thank the numerous ROTEM

users for their valuable discussions

during the last years, which contributed to this compendium.

We especially would like to thank and mention Prof. Dr. Wolfgang

Schobersberger, Prof. Dr. Petra Innerhofer and Dr. Dietmar Fries (A-

Innsbruck), Dr. Herbert Schöchl (A-Salzburg), Dr. Thomas Lang (D-

Hannover), Dr. Manfred Gütl (A-Graz), Prof. Dr. Sibylle Kozek-

Langenecker (A-Vienna) and Dr. Klaus Görlinger (D-Essen).

27 Guide ROTEM

Analysis - 09-2016

Guide ROTEM

Analysis - 09-2016 28

Aggregometry

Dr. Klaus Görlinger, An Ruland

Platelets are a key blood component in haemostasis. In response to a

vascular injury, they are able to adhere to the damaged vessel wall and

trigger an event that leads among others to aggregation of additional

platelets and therefore, together with other blood components, to the

formation of a stable clot.

The ROTEM

platelet module measures platelet aggregation

respectively via electrical impedance based on impedance

aggregrometry by Cardinal and Flower (1980).

The ROTEM

platelet module is an impedance aggregometer intended

for the assessment of platelet function in anticoagulated whole blood

samples. It provides quantitative and qualitative information about the

platelet aggregation by assessing the electrical impedance changes

after platelet activation with different reagents.

The ROTEM

platelet module is intended to be used in patients treated

with antiplatelet drugs or other drugs which may have an impact on

platelet function, as well as in patients with a suspected platelet

dysfunction due to extracorporeal circulation, trauma, sepsis or other

reasons. It is for use in clinical laboratories, hospitals or other clinical

care sites by health care professionals. The ROTEM

platelet module is

used in conjunction with the ROTEM

delta system, but does not

necessarily have to be complemented by viscoelastic testing.

Acute bleeding during or after surgery requires rapid differentiation

between surgical induced bleeding and haemostasis disorders. The

combination of the ROTEM

delta with the ROTEM

platelet and

additional diagnostic methods, considering the given limitations,

facilitates further differential treatment strategies.

29 Guide ROTEM

Analysis - 09-2016

ROTEM

platelet system

• 2 channels for simultaneous assays

• Can be used while thromboelastometry measurements are running

• Used in combination with ROTEM

delta

• Electronic pipetting facilitates the use outside of established

laboratories

• Ready to use single use reagents

Guide ROTEM

Analysis - 09-2016 30

Detection method: impedance aggregometry with ROTEM

platelet

Whole blood is pipetted into a cuvette containing a stirring bar and

special electrodes, energized with a certain voltage. Before inducing

platelet aggregation, an impedance baseline is determined. After adding

aggregating agents, the platelets are activated and start to aggregate.

The increase of the electrical impedance is measured over

the time of aggregation. It is directly proportional to the extent of platelets

involved in coating the electrodes by aggregation. The results of the

measurement are processed with a specific software.

The parameters of ROTEM

platelet analysis

AUC (Area under the curve):

The AUC represents the area under the aggregation curve from

the start of the measurement until 6 minutes of runtime.

AUC reflects the overall platelet aggregation.

MS (Maximum Slope):

The MS is the maximum slope to the aggregation graph.

MS is a measure for the rate of aggregation.

A6 (Amplitude at 6 minutes):

The A6 reflects the measured impedance, 6 minutes after

starting the test.

A6 is a measure for the extent of platelet aggregation.

31 Guide ROTEM

Analysis - 09-2016

ROTEM

platelet detection method

ROTEM

platelet parameters and scaling

Guide ROTEM

Analysis - 09-2016 32

ROTEM

platelet tests

The ROTEM

platelet analysis extends the resulting diagnostic power

by a number of additional tests and parameters, which

• allow differentiation between different platelet drug effects on platelet

aggregation.

• allow to detect platelet dysfunction due to e.g. extracorporeal assist

devices, surgery...

In ARATEM, the platelets are activated with arachidonic acid. Platelet

function is assessed for example in patients treated with

cyclooxygenase inhibitors (e.g. acetylsalicylic acid).

In ADPTEM, the platelets are activated with adenosine diphosphate.

Platelet function is assessed for example in patients treated with ADP

receptor antagonists (e.g. clopidogrel).

In TRAPTEM, the platelets are activated with thrombin receptor

activating peptide. Platelet function is assessed for example in patients

treated with PAR-1 receptor antagonists (e.g. vorapaxar) or GP IIb/IIIa

receptor antagonists (e.g. abciximab).

1.Petricevic M.et al.; Bleeding risk assessment in patients undergoing elective

cardiac surgery using ROTEM

platelet and Multiplate

impedance

aggregometry. Anaesthesia 2016 Jun; 71(6):636-47

33 Guide ROTEM

Analysis - 09-2016

ROTEM

platelet tests

ARATEM:

platelet activation

with arachidonic acid

ADPTEM:

platelet activation

with ADP

TRAPTEM:

platelet activation

with TRAP

Guide ROTEM

Analysis - 09-2016 34

ROTEM

platelet expected values

On the opposite page, typical ROTEM

aggregometry values are

shown, which are found when healthy patients without aggregation

disorders who are not taking antiplatelet drugs are analysed. Depending

on the examined population, these values can vary. It is therefore

recommended, at implementation of ROTEM

platelet, to analyse some

patients without pathological findings in order to establish respective

'local' reference ranges.

The reference values for the different tests depend on the sample type

used (citrate, heparin or hirudin sample tubes).

Interpretation of ARATEM, ADPTEM, TRAPTEM

In case of impaired platelet function, several parameters (AUC, A6 and

MS) are reduced. The cause of platelet impairment may be anti-platelet

or other influencing drug intake or non-drug induced (e.g. due to

cardiopulmonary bypass, extracorporeal assist devises, trauma,

surgery, infection or sepsis or in cases of thrombocytopenia).

Non-drug induced platelet dysfunction may be detected on all tests

(ARATEM, ADPTEM and TRAPTEM). However, in sepsis

for example,

the effect may be more pronounced on the ADPTEM test and in trauma

on the TRAPTEM test. Drug induced platelet dysfunction may show

different test patterns depending on the drug (see below, page 37).

1.Adamzik M. et al.; Whole blood impedance aggregometry as a biomarker for the

diagnosis and prognosis of severe sepsis. Crit. Care. 2012 Oct 22; 16(5):R204

2.Chapman MP et al.; Early TRAP pathway platelet inhibition predicts

coagulopathic hemorrhage in trauma. Shock.2015; 43 (6 Suppl1):33

35 Guide ROTEM

Analysis - 09-2016

ROTEM

platelet preliminary reference ranges

For citrated samples

For heparinized samples

For hirudinized samples

Test

/ Parameter

AUC

(Ohm*min)

(Ohm)

(Ohm/min)

ADPTEM (n=20) 56-139 16-38 4-11

TRAPTEM (n=175) 61-156 15-36 5-14

ARATEM (n=20) 70-153 19-41 6-13

Test

/ Parameter

AUC

(Ohm*min)

(Ohm)

(Ohm/min)

ADPTEM (n=20) 57-133 16-34 4-12

TRAPTEM (n=60) 66-169 15-38 6-18

ARATEM (n=20) 69-144 17-37 6-14

Test

/ Parameter

AUC

(Ohm*min)

(Ohm)

(Ohm/min)

ADPTEM (n=20) 86-201 23-52 7-17

TRAPTEM (n=60) 67-155 17-37 6-15

ARATEM (n=20) 84-193 21-52 7-16

Guide ROTEM

Analysis - 09-2016 36

Assessment of the ROTEM

platelet analysis

Drug induced or non-drug induced platelet dysfunction is detected by

decreased AUC, A6 and MS test results.

A. In patients treated with cyclooxygenase inhibitors (e.g. acetylsalicylic

acid) platelet aggregation may be impaired. This will be detected in the

ARATEM test.

B. In patients treated with ADP receptor antagonists (e.g. clopidogrel)

platelet aggregation may be impaired. This will be detected in the

ADPTEM test.

C. In patients treated with dual antiplatelet therapy (e.g. acetylsalicylic

acid and clopidogrel) platelet aggregation may be impaired. This will be

detected in ADPTEM and ARATEM.

D. In patients treated with PAR-1 receptor antagonists (e.g. vorapaxar)

platelet aggregation may be impaired. This will be detected in

TRAPTEM.

E. In patients treated with GP IIb/IIIa inhibitors (e.g. abciximab) platelet

aggregation may be impaired. This will be detected in all tests: ADPTEM,

TRAPTEM and ARATEM.

Non-drug induced platelet dysfunction may also show impaired platelet

aggregation (e.g. due to cardiopulmonary bypass, extracorporeal assist

devises, trauma, surgery, infection or sepsis or in cases of

thrombocytopenia). This may be detected in all tests: ADPTEM,

TRAPTEM and ARATEM. However, in sepsis for example, the effect

may be more pronounced on the ADPTEM test and in trauma on the

TRAPTEM test.

Limitations

Low platelet count may show abnormal aggregation.

37 Guide ROTEM

Analysis - 09-2016

Assessment of the ROTEM

platelet analysis

Examples of impaired platelet aggregation after drug intake.

A. Patient treated with acetylsalicylic acid:

B. Patient treated with clopidogrel:

C. Patient treated with clopidogrel and acetylsalicylic acid:

D. Patient treated with vorapaxar:

E. Patient treated with abciximab:

Guide ROTEM

Analysis - 09-2016 38

Assessment of the ROTEM

platelet analysis

As in all diagnostic tests, correct pre-analytics and correct performance

of the assay are essential for meaningful results.

“Correct sampling“ means: Complete filling of the sampling tube (in order

to ensure the correct anticoagulant-blood ratio); avoidance of

haemolysis during sampling (prevent excessive stasis, use of a needle

with sufficiently wide diameter).

Three sample tube types may be used: heparin, citrate and hirudin.

Normal values have been established for each sample type in

combination with all available tests. Citrated samples are not

recommended in situations where the patient‘s blood may contain

heparin. According to the chosen anticoagulant in the sample tube, the

corresponding sample resting time (between 2-30 min.) needs to be

observed (refer to the reagents‘ instructions of use).

A pneumatic tube transportation system may influence the sample‘s

platelets. As a precaution, this should be verified (split the sample and

analyse with/without transport by the tube system).

The samples should be stored at room temperature until analysis.

ROTEM

platelet analysis should be performed within two hours after

blood sampling.

The steps to be performed for ROTEM

platelet analysis are shown on

the right. The test operation is generally simple - also for staff without any

laboratory experience. Nevertheless, a certain familiarisation period and

motivation are necessary.

Apart from the correct performance of the analysis – as in every

laboratory test – the plausibility control of the analysis is important.

Measurements with irregular shapes (e.g. noised curves), generally

accompanied by error messages, should be repeated.

In case of unexpected results, a normal donor sample with known

aggregation level should be tested to verify system integrity. The normal

donor should not have ingested acetylsalicylic acid or clopidogrel or

acetylsalicylic acid- or clopidogrel-containing compounds in the

preceding 10 days.

39 Guide ROTEM

Analysis - 09-2016

Performing a ROTEM

platelet test

1. Insert the cuvette 2. Select test, enter/

scan patient data

3. Pipetting steps

are displayed on the

screen

4. Pipetting of

diluent, blood and

reagent

5. On screen display of

graphs and numeric

parameters

6. Discard used

cuvette

Guide ROTEM

Analysis - 09-2016 40

Differential diagnosis and therapy: algorithms

Acute bleeding during or after surgery requires rapid differentiation

between surgical induced bleeding and haemostasis disorders. The

combination of the ROTEM

delta with the ROTEM

platelet and

additional diagnostic methods, considering the given limitations,

facilitates further differential treatment strategies.

Patient drug history

ROTEM

delta

analysis

Bleeding patient

ROTEM

platelet

analysis

Abnormal

Abnormal Normal Normal

Consider

surgical bleeding

Haemostasis disorder:

Coagulopathy

(or thrombocytopenia)

Haemostasis disorder:

Platelet dysfunction

(or thrombocytopenia)

41 Guide ROTEM

Analysis - 09-2016

Differential diagnosis and therapy: algorithm example

Severe Bleeding Algorithm

Diffuse bleeding and

blood transfusion considered

< 35 mm or

FIB

> 600 s or

5% (within 60 min)

Tranexamic acid

25 mg/kg as a single

bolus

(if not already given prophylactically)

< 35 mm

and

FIB

< 8 mm (12 mm)

Fibrinogen concentrate

or Cryoprecipitate

(dose cal.)

Target: A5

FIB

≥ 12 mm

(16 mm)

< 35 mm and

FIB

≥ 8 mm (12 mm)

or platelet dysfunction

Platelet concentrate

1-2 pooled or

apheresis

> 80 s

PCC 15-25 IU / kg bw

FFP 10-15 mL / kg bw

> 240 s CT

HEP

> 240 s

Consider FFP

10-15 mL / kg bw

Consider Protamine

25-50 mg (2.5-5 mL)

Re-check after 10-15 min

using a new blood sample

Ongoing bleeding

YES

DONE

Hemorrhagic shock or

BE < -6 mmol/L or

Hb < 10 g/dL or

ISS ! 25 or

TASH-Score ! 15

YES

CHECK

Platelet concentrate (PC) transfusion:

Check platelet function with ROTEM® platelet (ADPTEM and TRAPTEM)

Consider tranexamic acid (25 mg/kg) and/or desmopressin (DDAVP; 0.3µg/kg)

in patients with dual antiplatelet therapy and/or ADPTEM < 30 Ω·min

Expected increase per pooled/apheresis PC per 80 kg: 8-10 mm in A5

→

< 35 mm (or ADPTEM < 30 Ω·min): 1 pooled or apheresis PC

< 25 mm (or ADPTEM < 30 Ω·min and TRAPTEM < 50 Ω·min): 2 pooled or apheresis PC

< 15 mm: 2 platelet concentrates + fibrinogen substitution (≥ 4 g)

Dr. Andreas Calatzis, PD Dr. med. Michael Spannagl

Department for haemostasis and transfusion medicine

University Clinic, Ludwig-Maximilian University

Ziemssen Str. 1, 80336 Munich, Germany

Dr. med. Matthias Vorweg

Cologne's City Hospitals gGmbH

OP Management

Ostmerheimer Str. 200, 51109 Cologne, Germany

Dr. med. Klaus Görlinger

Medical director - TEM international GmbH

Martin-Kollar-Str. 13-15, 81829 Munich, Germany

An Ruland

Product Manager - TEM international GmbH

Martin-Kollar-Str. 13-15, 81829 Munich, Germany

The ROTEM

system is an improvement of thromboelastography as

described by Professor Helmut Hartert. Andreas Calatzis developed the

ROTEM

system in collaboration with the physicist Pablo Fritzsche.

Michael Spannagl is a consultant for internal medicine and angiology. He

has been working for many years on the diagnosis and management of

acute and chronic disturbances of the haemostatic system. Matthias

Vorweg, University Hospital Bonn, has introduced ROTEM

analysis in

the anaesthesiology department of the Cologne-Merheim hospital more

than 10 years ago. The Cologne-Merheim hospital was one of the first

centres to introduce the concept of the ROTEM

based differential

diagnosis and targeted therapy in the clinical routine. Klaus Görlinger

was the ROTEM

pioneer in the Department of Anaesthesiology of the

University Hospital Essen. One of his major fields of expertise is the

development and implementation of Point of Care (POC) guided

algorithms for goal directed coagulopathy management. Dr. Görlinger is

now the medical director of TEM international in Munich, Germany.

ROTEM

is a registered trademark of Tem Innovations GmbH, Munich, Germany.

Manufacturer:

Tem Innovations GmbH

Martin-Kollar-Str. 13-15

D-81829 Munich

Phone +49 (89) 45 42 95-0

Fax +49 (89) 45 42 95 22

[email protected]