massive transfusion protocol

1. Role of the massive transfusion
protocol in the management
of haemorrhagic shock
J. H.Waters
Department of Anesthesiology, MageeWomens Hospital, University of Pittsburgh
Medical Center, Pittsburgh, USA
British Journal of Anaesthesia 113 (S2): ii3–ii8 (2014)
Supervisor 王審之醫師
Speaker 醫六 莊奕翰
DEC 30st
in 2014

2. Background
▪ From the experience gained during the Iraq and Afghanistan
conflicts, a concept of damage control resuscitation has arisen.
– Blood is delivered expeditiously to the bleeding patient, generally in a fixed
ratio.
– 1 unit of packed erythrocytes to 1 unit of plasma to 1 unit of platelets
▪ At the author’s institution
– PRBC: FFP: Platelet=10:6:2
▪ O+
uncrossmatched packed red blood cell
▪ AB plasma

4. Novelty
▪ Close inspection of these fixed-ratio transfusion protocol studies.
– Important limitations are noted in their interpretation including a prominent
effect of survivor bias.

5. Borgman et al. J Trauma 2007
▪ a retrospective chart review of massive transfusion at a US Army
combat support hospital.
– Massive transfusion was defined as >10 RBC units in 24 h.
▪ From this nonrandomized, retrospective analysis, the authors
concluded that a higher ratio of plasma to erythrocytes contributed
to a better outcome.

6. Differences in severity on presentation
▪ What seems to have been neglected in the analysis was that the
patients who received the high ratio had lower rates of thoracic and
head injuries.
▪ On presentation to the combat hospital, the low ratio group was
more acidotic, more coagulopathic, and more anaemic than the high
ratio group.
▪ For the patients who died in the low ratio group, they did so at an
average of 2 h from arrival into the combat facility;
– whereas, the patients in the high ratio group died on average at 37 h and died
more commonly from sepsis, multi-organ failure, and central nervous system
injury.

7. Cotton et al. J Trauma 2008
▪ A retrospective civilian study involving 16 level I trauma centres.
– 10 units PRBC in first 24 hours
– PRBC: FFP: platelet = 10:4:2
▪ Same bias: differences in severity on presentation
– Truncal and head injury in 58% of the low ratio patients and 23% in the high ratio
patients.
– Low ratio groups: received erythrocytes at a rate of 5.25 units per hour before
death
– Fixed ratio groups: at a rate of 0.63 units per hour

8. Survivor bias
▪ Survivor bias is associated with having survived long enough to
receive a particular therapy.

9. Snyder et al. J Trauma 2009
▪ more than 10 units PRBC in 24 hours.
▪ Total 134 patients were included
– Nonsurvivor: higher Injury severity score and
admission base deficit.
– 54% of in-hospital deaths occurred within 6
hours.

10. Cumulative FFP:PRBC ratio

11. Adjust for the survival bias

12. Effect of plasma on coagulation function
▪ These risks primarily relate to acute allergic reactions, transfusion
related acute lung injury and transfusion associated circulatory
overload.
▪ Some plasma can have an INR as high as 1.3.
– The INR of transfused plasma ranges from < 1 to > 1 based on the donor and the
effect of storage.
▪ 10% increase of plasma coagulation factor concentration
– 4 units of FFP(around 250ml)
– the effect is much greater at higher INRs (3.0 -> 2.3; 1.5-> 1.4)
▪ Recent evidence suggests that conventional laboratory tests of
coagulation are insensitive in detection acquired coagulopathy as in
trauma, or in guiding procoagulant therapy.

13. Adverse effects of aggressive plasma use
▪ Transfusion increased the survival in a patient population where 50%
of the patients were predicted to die; whereas, the plasma
transfusion increased the risk of death in a cohort of patients that
had a predicted risk of death <20%.
▪ An increased risk of multiple organ failure when patients were
transfused aggressively with plasma.
▪ In the bleeding patient, more plasma might have unpredictable
results when given using a fixed ratio strategy.

14. Laboratory-guided plasma use
▪ Traditional laboratory testing provides slow information.
– Point of care test allows for rapid testing and resulting of coagulation data at the
point of the patient bedside.
▪ Point-of-care devices that have been used for this purpose include
the thromboelastograph, the Rotem, and the Sonoclot.
– Each of these devices measures viscoelastic changes in whole blood as it clots.
▪ Multiple investigators have now shown improved outcomes when
using a goal-directed strategy of transfusion compared with fixed
ratio strategies
– In trauma patients and cardiac surgery

15. Conclusions
▪ The immediate benefits of plasma transfusion only outweigh the
risks when a coagulopathy is severe.
▪ However, overall risks increase with escalating plasma exposure,
thus affecting patient safety.
▪ Point-of-care coagulation monitoring can be used to avoid excessive
allogeneic blood transfusions including plasma and its associated
complications.

16. What I learn from this……
▪ Point-of-care viscoelastic testing of whole blood coagulation
provides an individualized approach to reduce unnecessary plasma
transfusion and avoid associated complications.

17. Thx for attending