Page 54 - JSOM Spring 2023

The authors acknowledge that warming patients is a “bundle” such as forced-air warming systems were often documented,
of various efforts. Additional interventions such as removing other routine interventions such as warmed blankets or “bun-
wet clothing, applying blankets, and controlling indoor ambi- dling” may not have been documented.
ent temperature are important to maintaining normothermia.
The authors feel that these data support transfusing warmed When assessing pre- and post-transfusion blood pressure
prehospital blood to minimize body temperature change in (i.e., SI), both manual and automated blood pressures were
critically ill patients. Future research might take into account included, and the measurement modality was not always doc-
the warming treatment “bundle” as a whole. umented in charting. Finally, children were not included in this
study, and the results may not be generalizable to a pediatric
population.
Limitations
The authors recognize several limitations to this study. First, Conclusion
the modality for post-transfusion temperature measurement
was not standardized, and included the following routes: oral,
cutaneous, rectal, and temperature-sensing bladder catheter. These data are favorable in support of warmed prehospital
Sund-Levander et al. investigated normal body temperature blood transfusion in preventing body- temperature decrease
in adults by oral, rectal, tympanic, and axillary routes. Their in critically ill patients. This retrospective descriptive study
results suggested that, when looking at studies with “strong or demonstrates that in this patient population, only two of 69
fairly strong evidence” of normal body temperature, the rectal patients (3%) had a decrease in temperature that led to hypo-
route was only slightly higher (36.9°C) when compared to oral thermia upon ED arrival. Overall, there was no statistically
13
(36.4°C), tympanic (36.5°C) and axillary (36.3°C) means. significant difference in pre- and post-transfusion body tem-
Additionally, there were possibly pertinent differences in the perature, including two patients receiving large-volume trans-
timing of temperature acquisition upon patient arrival to the fusions with eight units of blood products each.
hospital. Critical trauma patients, for example, may not have
had their temperature obtained until other aspects of the pri- Acknowledgments
mary assessment were performed. The authors wish to thank Life Warmer, the manufacturer of
the Quantum Blood & Fluid Warming System. This work was
Per protocol, patients may have received intravenous (IV) in-part supported by Life Warmer through an unrestricted
fluids prior to blood administration. Volume of crystalloid educational grant. The authors also wish to acknowledge the
transfused was not accounted for in this analysis. Prehospi- exceptional PHAS clinicians and their dedication to advanc-
tal fluids are stored in the temperature-controlled patient-care ing the science, practice, and technology of emergency medi-
compartment of the ambulances and are not warmed. The ad- cine. Through their 24-hour-a-day, compassionate and expert
dition of an unknown amount of non-warmed crystalloid IV emergency care, they make a difference in the health of their
fluid would be expected to exacerbate a decrease in body tem- patients and the community that they serve.
perature, although the temperature difference between room-
temperature IV fluid and body temperature is small compared Funding
to that of refrigerated blood. It is possible the addition of This work was in-part supported by Life Warmer through an
warmed blood products mitigated the potential crystalloid unrestricted educational grant.
fluid temperature drop but this is unknown. Regardless, it ap-
pears that in this study patient population, the crystalloid fluid Disclosure
volume does not appear to influence the results. Future work The authors have indicated they have no financial relation-
may consider comparing the effects of warmed IV fluid versus ships relevant to this article to disclose.
ambient-temperature fluid on body temperature.
Author Contributions
It must be considered that there may have been inconsistencies All authors conceived the study. EM prepared the initial proto-
in documentation, particularly related to home medications col; EM, RP, and AD drafted the manuscript. EM, AD, and LE
that may have affected physiological parameters from the time collected and organized data. Data analytics were performed
of EMS intervention to ED assessment. Patients may not have by the Prisma Health-Upstate Biostatistics team. All authors
had updated medication lists in their chart or may have had read and approved the final manuscript.
inconsistent adherence to their regimens.
Funding
For those patients who were excluded from data analysis due This work was in-part supported by Life Warmer through an
to incomplete vital sign documentation and no documented unrestricted educational grant.
temperature, it should be acknowledged that a febrile transfu-
sion reaction could have been overlooked. However, no trans- References
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52 | JSOM Volume 23, Edition 1 / Spring 2023