Page 78 - JSOM Spring 2023

FIGURE 1 Suggested decision tree for discriminating a febrile non-hemolytic reaction (FNHTR) from a septic reaction.
New onset fever during transfusion

Magnitude of temperature change ≥1–2°C Magnitude of temperature change ≥2°C

Suspicious for FNHTR Suspicious for septic reaction

Look for other evidence of a systemic inflammatory Monitor vital signs especially
response such as rigors/chills, diaphoresis, blood pressure, heart rate, and oxygen saturation
subjective hot or cold feeling

Vital signs stable, especially blood pressure, Terminate the transfusion If stable, continue with
heart rate, and saturation if other evidence of sepsis the transfusion with close
(hypotension, hypoxia, monitoring of vital signs
shock etc.) present or and consider treatment
Continue with the transfusion with close monitoring index of suspicion for with anti-pyretics
of vital signs and consider treatment with anti-pyretics sepsis is high
Note that clinical judgement and the patient’s status are also important factors to consider when deciding if the transfusion should be perma-
nently discontinued.
pain, unexpected oozing of wounds [concerning for dissem- • If the patient receiving a transfusion develops unexpected
inated intravascular coagulation (DIC)], and significant acute hypotension, shock, significant dyspnea/hypoxia, or a par-
respiratory distress can also be found in both septic and acute ticularly high fever during a transfusion, the transfusion
hemolytic reactions. But again, these would not be expected to should be paused but not disconnected from the patient
occur in a FNHTR. The magnitude of the temperature change, until other causes of these changes can be investigated.
such as a rise in temperature ≥2°C above baseline and one that • When pausing a unit, consider that most regulatory asso-
exceeds 39°C, has also been proposed as a criterion to dis- ciations in the United States [Association for the Advance-
criminate a septic reaction from an FNHTR. However, clinical ment of Blood & Biotherapies (AABB) and the Food &
changes in the patient’s physical examination and vital signs are Drug Administration (FDA)] recommend completing a
probably better indicators of a severe reaction than the mag- blood infusion within four hours.
nitude of the temperature change or their maximum tempera- • If a severely hypovolemic patient is suspected of having a
ture. For the provider preparing to administer a unit of blood, transfusion reaction, and circumstances permit, consider
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one should remember to inspect the unit prior to starting the switching blood units, but remember that the patient needs
infusion for signs of gross bacterial proliferation – change in blood.
color from the usual dark red, excessive bubbles or evidence of • In the extremely unlikely event that a transfusion reaction
gas formation (higher than normally expected from agitation of leads to shock, this compounds the physiologic effects of
the blood), and any particulates floating in the product. hemorrhagic shock. The patient can be thought of as hav-
ing “shock squared.” This unfortunate circumstance should
To make discriminating these reactions even more compli- prompt a rapid inventory of resources and a triage decision:
cated, it is possible that septic and acute hemolytic reactions double down on resuscitation if resources (medications and
might pass completely unobserved. This is because they may more blood products) are available or focus efforts on pa-
cause minimal changes in the patient’s vital signs, or the treat- tients who can be salvaged with what is at hand.
ing provider may ascribe small changes in status or vital signs • Blood products in the field are a scarce commodity. Pre-
to the patient’s underlying condition (i.e., not all septic reac- maturely terminating a field transfusion should only be
tions feature temperature increases of ≥2°C). Furthermore, done if the transfusion has seriously worsened the patient’s
many trauma patients will receive antibiotics early during condition.
their treatment according to the Tactical Combat Casualty
Care (TCCC) guidelines. This may blunt the clinical manifes- Crystalloids for a Hemorrhaging Patient? No.
tation of a septic reaction in a similar manner to the way that
anti-pyretic treatment might prevent a rise in temperature and For many years, resuscitation protocols focused on the early
mask a FNHTR. and aggressive use of crystalloids, such as normal saline, be-
cause they were inexpensive, easily transported at room tem-
When managing a suspected transfusion reaction, keep these perature in resilient plastic bags, and they did not carry the
points in mind: infectious and non-infectious risks of transfusing human
blood products. It was thought that if the patient’s hemody-
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• Only patients at risk of death due to hemorrhage should namics could be maintained using crystalloids, then the large
receive prehospital transfusions. physiologic reserve of hemoglobin in red blood cells (RBC)
• A patient having an adverse reaction to transfusion is still and clotting factors in plasma and the extravascular space
in or is at imminent risk for hemorrhagic shock and there- would reach their respective tissue destinations and perform
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fore needs blood. their functions. Guided by this philosophy, liters of crystalloid
76 | JSOM Volume 23, Edition 1 / Spring 2023