Transcript Anemia and transfusion guidelines in adults

Pablo M. Bedano M.D.
Community Regional Cancer Care
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Treatment of symptomatic anemia
Prophylaxis of life threatening
anemia
Restoration of oxygen-carrying
capacity in the case of hemorrhage
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Oxygen delivery (DO2)= cardiac output x
arterial O2 content
At rest in healthy adults delivery exceeds
consumption x4
Delivery can be raised by increasing cardiac
output
Ill adults with other medical comorbidities may
have impaired compensatory mechanisms
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31 healthy adults had aliquots of blood (450-900
ml) removed to achieve Hgb 5 g/dL
Isovolemia was maintained
Statistically significant increases in heart rate and
stroke volume (increased cardiac output)
Cognitive function impaired at Hgb 5-6
No increase in plasma lactate concentration
2 individuals developed reversible EKG changes
consistent with ischemia
Weiskopff et al JAMA. 1998 Jan 21;279(3):217-21.
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A retrospective cohort study of 1958 patients who
declined transfusion for religious reasons showed
30 day mortality 1.3% Hgb >12 g/dL, 33% if Hb
<6, greater odds of death if underlying CV disease
A subset analysis of 300 post-operative patients
postoperative risk of death increased progressively
when Hb < 7 g/dL
Retrospective review of 310,311 patients
undergoing non-cardiac surgery revealed 10%
increase cardiac events Hct 36-38.9, 52% Hct 1820.9
Carson et al Lancet 1996; 348:1055
Carson et al Transfusion 2002; 42:812
Wu et al JAMA 2007; 297:2481
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Infection
Allergic reactions
Volume overload
Iron overload
Cost
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Hgb < 6 g/dL – Transfusion recommended except
in rare circumstances
Hgb 6 to 7 g/dL – Transfusion likely to be
recommended
Hgb 7-8 g/dL – Consider transfusion in
postoperative surgical patients
Hgb 8-10 g/dL – Transfusion generally not
indicated, consider in special situations
(symptomatic anemia, ongoing bleeding, acute
coronary syndrome with ischemia
Hgb > 10 g/dL – Transfusion generally not
indicated
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19 randomized clinical trials identified including 6264
patients
All trials included used a transfusion threshold
Most trials used thresholds between 7-10
39% decrease in probability of receiving transfusion
Fewer units (1.19) transfused per patient
Trend towards lower 30 day mortality
Trend toward lower infection rate, no difference seen
with pneumonia
No difference in functional recovery or length of stay
Carson et al JAMA 2013; 309:83
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No increased risk of MI found on meta-analysis
TRICC 838 ICU patients with Hgb <9 within 72 hs.
admission, randomized to liberal (Hgb>10) vs.
restrictive (hgb>7). Lower overall mortality in
restrictive group, lower risk of MI (0.7 vs 2.9%)
FOCUS 2016 patients >50 with history or risk
factors for CAD and Hgb < 10 g/dL after hip
surgery randomized to liberal (Hgb>10) or
restrictive (Hgb>8) transfusion threshold. Nostatistically significant increase of MI (3.8 vs 2.3).
No difference in survival
Hebert et al NEJM 1999; 340:409-417
Carson et al NEJM 2011; 365(26):2453-62
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Most guidelines recommend transfusion when
Hgb between 8-10 g/dL in the setting of active
ischemia
Pilot trial 110 patients with ACS undergoing
cardiac cath. with Hgb < 10 g/dL. Randomized
to liberal (>10) vs restrictive (>8). Endpoint
death, MI or revascularization <30 days. Trend
to better outcome in liberal group (10.9% vs
25.5% P=0.54)
Carson et al Am Heart J 2013; 165:964
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AABB guidelines recommend transfusion
threshold of 8 g/dL in asymptomatic patient
and 7-10 g/dL in symptomatic patient
Fluid overload is a concern
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In case of massive bleeding transfusion should be
guided by rate of bleeding and not Hgb
Hemodynamically stable patients restrictive
strategy may be safe
Single center trial randomized 921 patients with
acute upper GI bleed to restrictive (Hgb>7) vs
liberal (Hgb >9) strategy, excluding massive
bleeding, ACS or CVD. All patients underwent
endoscopic treatment within 6 hs
Lower rate of transfusion (49 vs 89 percent)
Fewer deaths from bleeding (0.7 vs 3.1 percent)
and from any cause (5 vs 9 percent)
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Based on FOCUS trial a transfusion threshold of
Hgb 8 g/dL seems to be safe
Hgb threshold of 8 g/dL seems safe in patients
undergoing cardiac surgery with cardiopulmonary
bypass
428 patients randomized to threshold 8 vs 9, no
differences in outcome
TRACS 502 patients undergoing cardiac surgery
with CP bypass, no differences in outcome.
Independent of transfusion strategy, overall
mortality correlated with number of transfusions
Bracey et al Transfusion 1999;39:1070
Hajjar et al JAMA 2010; 304:1559
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In patients undergoing active treatment
maintain Hgb > 7-8 g/dL
No randomize studies to guide palliative
benefit of blood transfusions in terminal
patients
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Multiple clinical trials validate a restrictive transfusion
strategy for most adults, with threshold Hgb 7-8 g/dL
In medically stable ICU patients Hgb threshold of 7
g/dL safe based on TRICC trial
Symptomatic patients with Hgb <10 g/dL should be
transfused as clinically indicated
In patients with acute coronary syndrome, Hgb should
be kept > 8 g/dL and > 10 g/dL in ongoing ischemia
Patients with massive bleeding cannot be managed
based on Hgb thresholds
Transfusion on 1 unit of blood at a time is reasonable in
the hemodynamically stable patient