Transcript Early Packed Red Blood Cell Transfusion and Acute

Transfusion Medicine Journal Club
Omar Al Suhaibani
24th March,2009
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Transfusion therapy is common in trauma
patients.
Transfusion of PRBCs, platelets, and fresh
frozen plasma are all associated with the
development of ARDS in trauma patients.
Massive transfusion (more than 10 units of
PRBCs within a 12- to 48-h interval) has been
identified as a risk factor for ARDS in trauma
patients.
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Massive transfusion is defined as 10 or more
RBC units in a 24 hour period
Massive transfusion occurs in up to 15% of
civilian trauma patients
Massive transfusion is associated with a
mortality rate of 20-50%
Most patients requiring massive transfusion
die within 6 hours of admission
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American-European Consensus Conference
definition for ARDS:
- bilateral infiltrates on chest radiograph
- a PaO2/FIO2 ratio less than 200
- a pulmonary artery occlusion pressure of less
than 18 mmHg or no clinical evidence of left
atrial hypertension.
 Acute lung injury (ALI) is a less severe form of
ARDS defined by PaO2/FIO2 ratio less than 300
mmHg (within 6 h).
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Causal relationship between transfusion
products and ARDS.
Host reactions to antigranulocyte antibodies.
Interactions between non-specific systemic
inflammatory mediators such as interleukin 8
and tumor necrosis factor.
Depressed immune responses leading to a
higher risk of infection
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Neutrophils isolated from trauma patients
receiving PRBCs demonstrate neutrophil
priming as per measured increase in surface
expression of CD11b/CD18 receptor sites,
superoxide production and elastase release
all of which may predispose to ALI and ARDS.
Cryoprecipitate and FFP have the highest rate
of antibodies and are more associated with
both TRALI and ARDS compared to PRBCs.
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Observational prospective cohort.
688 patients with sepsis, trauma, aspiration,
and hypertransfusion.
PRBC transfusion was associated with ARDS
(aOR 1.52, 95% CI 1.00-2.31, p= .05)
PRBC transfusion was associated with
increased mortality in ARDS (aOR 1.10 per
unit transfused; 95% CI 1.04-1.17) with a
significant dose-dependant response (p=.02)
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Prospective cohort study.
102 consecutive patients with severe trauma.
Patients devided into 3 groups on the basis of
total number of PRBC units received in the
first 24 h.
0-5 units of PRBC = 21% ARDS
6-10 units of PRBC = 31% ARDS
Greater than 10 units of PRBC =57% ARDS
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Retrospective study.
103 patients received multiple transfusions
(more than 6 units of PRBC) in the first 24 h.
Total amount of transfusion in the first 24 h
was 14.0+/- 6.8 U in the ARDS patients and
10.6+/- 7.3 U in other patients (p=0.17)
ARDS in massively transfused patients was
less related to poly-transfusion than to other
factors related to circulatory shock, polytrauma or thoracic trauma.
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Single-center retrospective cohort study.
841 consecutive critically ill patients.
298 patients (35%) received blood
transfusion.
ALI/ARDS more likely to develop in patients
received FFP (OR, 2.48; 95% CI, 1.29-4.74)
and platelet transfusions (OR, 3.89; 95% CI,
1.36-11.52) than those who only received
PRBCs (OR,1.39; 95% CI, 0.79-2.43).
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Anesthesiology 2009; 110:351–60
Early Packed Red Blood Cell Transfusion and
Acute Respiratory Distress Syndrome after
Trauma
Onuma Chaiwat, M.D., John D. Lang, M.D., Monica S.
Vavilala, M.D., Jin Wang, Ph.D., Ellen J. MacKenzie, Ph.D.,
Gregory J. Jurkovich, M.D., Frederick P. Rivara, M.D.
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Data from National Study on Cost and
Outcomes of Trauma (NSCOT)
Multicenter prospective cohort study
Injured patients treated in 18 trauma centers
and 51 large non-trauma centers in 14 states
across the United States
18 month period July 1, 2001- Nov.30, 2002
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Inclusion criteria:
- patients 18-48 of age
- at least one injury of Abbreviated Injury Scale score of 3 or
greater
Patients were excluded if:
- no vital signs
- pronounced dead within 30 min of arrival
- had injury occurring more than 24 h before hospital arrival
- major burns
- primary diagnosis of hip fracture (65 yrs of age or older)
- spoke neither English nor Spanish
- non-US residents
- incarcerated or homeless at the time of injury
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14,070 patients were included.
Main exposure : number of units of PRBCs
received within the first 24 h of presenting to
hospital and this was analyzed both as
continuous variable and categorized into
four groups : 0, 1-5, 6-10, and >10.
Outcomes were the development of ARDS and
in-hospital mortality.
Diagnosis of ARDS was made by primary
physicians according to the AmericanEuropean Consensus Conference definition.
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Sequential regression imputation method was
used to perform the multiple imputations of
missing values.
Associations among patient characteristics and
ARDS and PRBCs transfusion units was
determined by using chi-square statistics and
t-test for categorical and continuous variables,
respectively.
Adjusted logistic regression method was
developed to determine which characteristics
were independently associated with ARDS.
Multivariate weighted logistic regression models
were used to determine the effect of PRBC
transfusion on ARDS and in-hospital mortality.
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Abbreviated Injury Scale (AIS) is an anatomical
scoring system .
first introduced in 1969.
Injuries are ranked on a scale of 1 to 6, with
1 being minor, 5 severe, and 6 a nonsurvivable injury.
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Injury Severity Score (ISS) is an anatomical scoring
system that provides an overall score for patients
with multiple injuries.
Each injury is assigned an AIS and is allocated to one
of six body regions (Head, Face, Chest, Abdomen,
Extremities (including Pelvis), External).
The 3 most severely injured body regions have their
score squared and added together to produce the ISS
score.
The ISS score takes values from 0 to 75.
The New Injury Severity Score (NISS) is calculated as
the sum of the squares of the top three scores
regardless of body region.
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Patients were primarily males (68.5%)
Blunt trauma (86.6%)
Non-Hispanic whites (60.2%)
Average age was 43.3
Mean injury severity score of 29.9
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ARDS developed in 521 patients (4.6%)
Total of 331 (63.5%) received early PRBCs
transfusion
Prevalence of ARDS increased with higher
units of early PRBCs transfusion
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Clinical predictors for ARDS in the final
logistic regression model.
Mean NISS, thoracic injury, poly-trauma,
pneumonia, and receiving more than 5 units
of FFP and 6-10 units of PRBCs.
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Risk Factor
Odds Ratio (95% CI)
Age, yr
1.02 (1.00-1.03)
NISS
1.02 (1.01-1.04)
Thoracic injury
1.57 (1.07-2.31)
Pneumonia
7.52 (4.48-12.60)
Poly-trauma
2.77 (1.62-4.74)
PRBC transfusion units
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Ref
1-5
1.70 (0.72-4.03)
6-10
2.24 (1.06-4.73)
> 10
2.18 (0.93-5.11)
FFP transfusion units
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Ref
1-5
1.66 (0.88-3.15)
>5
2.55 (1.17-5.55)
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Two multivariate logistic regression analyses
were performed.
Effects of PRBC units transfused in initial 24 h
after hospital admission categorized into four
groups, group 1 as a reference group
Greater risk for developing ARDS if pts
received more than 5 units of PRBCs
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PRBC units transfused during the first 24 h
categorized as continuous variable when
controlling for all confounding variables.
Effect of PRBCs transfused during first 24 h
remained significant for ARDS (adjusted odds
ratio 1.06, 95% CI 1.03-1.10).
6% higher risk of ARDS for additional unit of
PRBCs transfused.
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ARDS, aOR (95% CI) In-hospital death, aOR
(95% CI)
PRBC units
1-5
1.88 (0.77-4.62)
1.13 (0.64-2.02)
6-10
2.48 (1.175.26)*
1.52 (0.82-2.83)
> 10
2.62 (1.086.37)*
0.93 (0.27-3.17)
* P< 0.05; Referent group = 0 PRBC units
aOR = adjusted odds ratio
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Timing of ARDS onset.
Separation between ARDS and TRALI.
Leukoreduction of PRBCs??
Gender of donors.
Age of transfused PRBCs.
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“ early PRBCs transfusion is an independent
risk factor for ARDS in trauma patients, and
each unit of PRBCs transfused increases the
risk of ARDS by 6%.”
Conservative PRBC transfusion strategies
early after trauma may need to be considered
as part of early goal-directed therapy
protocols.
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“ Future randomized clinical trials will be
necessary to confirm the important results of
Chaiwat et al. so that the use of less blood
products during the initial resuscitation of
trauma victims actually decreases the risk of
developing ARDS. Less may actually be more.”
Benson et al, Anesthesiology 2009; 110:216–7
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Are the results of this study valid?
- Prospective cohort study with retrospective
analyses.
- Multicenter large sample size study.
- Incomplete or missing data.
- No trauma transfusion protocols.
- Outcomes were not measured in the same
way.
- Follow-up not sufficiently complete.
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Are the results of this study valid?
- Patients not treated equally.
- Patients were not similar to begin with
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Are the results of this study important?
- Yes, each unit of PRBC transfused in the
first 24 h increase the risk of ARDS by 6%.
Are these results applicable to our patients?
- Yes
Should I attempt to stop the exposure?
- Alternatives??
- Maybe review the ratio of plasma to PRBC.
- RCT is necessary but challenging.
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THANK YOU
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