Questions & Answers Booklet

Lipid / Leucocyte Reinfusion Filter for Salvaged Blood

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GENERAL

Q1. What are the clinical problems associated with

contaminants in salvaged blood?

■ Impaired lung function and reperfusion injury

■ Adult Respiratory Distress Syndrome (ARDS)

■ Brain Injury and Fat Embolic Syndrome (FES) - Lipid

■ Lung dysfunction - Microaggregates and surgical debris

Q2. Do you have any clinical data to support reinfusion

of post-operative shed blood?

A review of 87 papers by Munoz Gomez et al 1

concluded that “…salvaged filtered blood is a source of

red blood cells of sufficient quality to be safely reinfused

and that their reinfusion contributes significantly to

reduce the need for homologous blood.”

The American Association of Blood Banks (AABB) state

that “The collected blood can be processed with or without

cell washing, but must be filtered before reinfusion”.2,3

Q3. Are all filters the same?

There is a wide variation in filter types. The choice will

depend on the particular application and the level of

protection desired. Advice should be sought from the

manufacturer. Ideally for salvaged blood a filter with

enhanced lipid and leucocyte removal capabilities is

required to minimise subsequent clinical sequelae.

Q4. How does the Lipid/Leucocyte filter differ from

a standard screen filter?

The Lipid/Leucocyte incorporates a clinically proven 40 µm

screen filter for reduction of microaggregates and debris.

However, it also has additional media which typically

removes 84% of lipids and 71% of leucocytes.

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PRACTICAL ISSUES

Q5. What is the filter volume?

Approximately 20 ml

Q6. Why do we need to remove air in the bag when

priming the Lipid/Leucocyte filter? Can't you just

hang the bag up and run it through?

By removing as much air as possible this ensures that

the maximum filtration area is being used to reduce the

contaminants in the blood.

Q7. Does air affect the Lipid/Leucocyte filter i.e.

the air you need to remove from the bag,

before priming the filter?

If too much air is contained in the Lipid/Leucocyte filter

this can result in a reduced flow-rate or even blockage

of the device.

Q8. Does it matter if the entire Lipid/Leucocyte filter

is not quite primed when starting reinfusion?

A small volume (e.g. 1-2 ml) of air at the top of the

Lipid/Leucocyte filter housing should not cause any

problems. It is essential, however, to ensure that the

media is completely wetted as this gives optimal air

removal and filtration performance.

Q9. Does the line need priming with saline?

If you prime with saline how do you prime the

Lipid/Leucocyte filter?

The line does not need to be primed with saline, but if

this is your preferred practice then just replace the saline

bag with the blood bag ensuring as little air as possible is

transferred into the Lipid/Leucocyte filter.

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Q10. If the Lipid/Leucocyte filter is washed out with

saline at the end of use can you use it again?

What are the hazards of doing this?

The filter should not be re-used after indicated use. Also,

we do not recommend flushing the Lipid/Leucocyte filter

with saline as this may affect the binding capability of the

additional media in the filter. This could potentially result

in flushing retained contaminants from the filter.

Q11. How do I achieve a good prime?

The best way to prime the filter is to invert it after

spiking the blood unit. Loosen the administration set cap

(unless it is vented) and maintain an even pressure on

the bag before opening any clamps downstream of the

filter. Pressure should be evenly maintained until the

administration set is primed and the downstream clamps

closed. The blood unit can now be positioned on the

drip stand and the filter should be completely primed.

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LEUCOCYTES

Q12. What is a neutrophil?

This is the most abundant phagocytic leucocyte

i.e. it engulfs foreign debris and cells and can be

very aggressive.

Q13. What happens when a neutrophil is activated?

Cell salvaged blood contains numerous leucocytes of

which the neutrophils are in an activated state4.

They release reactive oxygen species, proteolytic enzyme

and lipid mediators. This can cause reperfusion injury.

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LIPID

Q14. Where does the lipid in salvaged blood come from?

■ Subcutaneous fat released from connective

tissue when cutting the skin

■ Bone marrow6 from when bones are cut or reamed7

■ Blood i.e. diet related

Q15. What symptoms are seen with Fat

Embolic Syndrome?

The patient must display 2 out of 3 major symptoms9,10.

■ Pulmonary distress

■ Mental disturbances

■ Petechial rash

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MICROAGGREGATE DEBRIS

Q16. What are microaggregates?

The clotting and coagulation cascades are stimulated

during the loss of blood at the wound site during

collection and handling of salvaged blood.

This induces the formation of microaggregates

composed of activated platelets, leucocytes and fibrin.

Additionally bone fragments, skin, cement and other

debris may be present in salvaged blood.

Q17. What are the clinical implications of

these contaminants?

If the blood is not adequately filtered then these debris

are capable of blocking capillaries thus affecting organ

function. The arterioles in the lungs are the body’s

natural filters and if these become blocked then this can

result in Adult Respiratory Distress Syndrome.

Q18. What is Adult Respiratory Distress

Syndrome (ARDS)?

This is a condition of diffuse pulmonary infiltrates,

refractory hypoxaemia and respiratory distress 15,16.

The patient requires ventilation and X-rays show

characteristic changes. In summary, the lung is unable

to function properly to oxygenate the blood before

passing to the heart.

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11. Blevins FT, Shaw B, Valeri CR, Kasser J, Hall J. Reinfusion of

shed blood after orthopaedic procedures in children and

adolescents. J Bone Joint Surg Am.

1993; 75(3):363-71.

12. Clements A, Mulholland J, Pope N. Scanning electron

microscopy of a lipid filter after use with washed

salvaged blood. Therapeutic Filtration and Extracorporeal

Circulation Conference (TFECC) 2003.

13. Fox MA. Filtration of shed mediastinal blood. Perfusion.

1993; 8:331-6.

14. Chapman, MJ. Adult respiratory distress syndrome -

an update [Web Page]. Available at http://www.nda.ox.ac.

uk/wfsa/dl/html/reviews/rev003.htm.

(Accessed 13 November 2003).

15. Petty TL, Ashbaugh DG. The adult respiratory distress

syndrome. Chest. 1971; 60(3):233-9.

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REFERENCES

1. Munoz Gomez M, Garcia Vallejo J, Lopez-Andrade

Jurado A, Gomez Luque A, Ruiz Romero De La Cruz

M, Maldonado Eloy-Garcia J. Autotransfusion after

orthopedic surgery. Analysis of quality, safety and efficacy

of salvaged shed blood. Rev Esp Anestesiol Reanim.

2001; 48(3 ):131-40.

2. American Association of Blood Banks (AABB). Blood

Transfusion Therapy: A Physicians's Handbook. 7th

edition. American Association of Blood Banks (AABB),

2002. (Triulzi D ).

3. Standards for perioperative autologous blood collection

and administration. 1st edition. Bethesda, M.D.:American

Association of Blood Banks, 2001. (Santrach PJ ).

4. Pertilla J, Leino L, Poyhonen M, Salo M. Leucocyte content

in blood processed by autotransfusion devices during

open-heart surgery. Acta Anesth Scand. 1995; 39:443-8.

5. Henn-Beilharz A KC . Retransfusion in bone surgery: what

happens to the fat? Anasthesiol Intensivmed Notfallmed

Schmerzther. 1991; 26(4):224-5.

6. Henn-Beilharz A, Hoffmann R, Hempel V, Brautigam KH.

The origin of non-emulsified fat during autotransfusions

in elective hip surgery. Anaesthesist. 1990; 39(2):88-95.

7. Brooker RF, Brown WR, Moody DM et al. Cardiotomy

suction: A major source of brain lipid emboli during

cardiopulmonary bypass. Ann Thorac Surg. 1998;

65:1651-5

8. Johnson MJ, Lucas GL. Fat embolism syndrome.

Orthopedics. 1996; 19(1):41-8.

9. Gossling HR, Donohue TA. The fat embolism syndrome.

JAMA. 1979; 241(25):2740-2.

10. Barnett M. The origins, clinical significance and visual

perception of particulate matter. American Society for

Parenteral and Enteral Nutrition (ASPEN) 20th Clinical

Congress. 178-82.

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Printed in England. PMED/0.1M/DBD/4.2004

The information provided in this literature was reviewed for accuracy at the time of publication. Product

data may be subject to change without notice. For current information consult your local Pall distributor

or contact Pall directly. Part numbers quoted above are protected by the Copyright of Pall Europe Ltd.

, Pall and LipiGuard are trade marks of Pall Corporation.

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