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Sanid. mil. 2021; 77 (4) 175
Sanidad Militar
Revista de Sanidad de las Fuerzas Armadas de España
Sanid. Mil. Volumen 77, número 4. ISSN: 1887-8571 Octubre-Diciembre 2021
CONTENTS
EDITORIAL
178 Primer Congreso de Sanidad Militar de la Unión Europea
Sánchez-Ramos J.J
ORIGINAL ARTICLE
180 Cryopreserved red blood cells, what’s left at the end of the road?
López-Aguilar JC. , Cascante-Ruiz V., Núñez-Márquez L., Ramos-Garrido A.
SUMMARY: Background and Objectives: Cryopreserved red blood cells have a very long shelf life, however once thawed,
they must meet demanding quality requirements and have a short shelf life. The objective is to evaluate the quality of the
final products obtained from cryopreserved red blood cells stored in the CTFAS and the evolution of the quality parameters
after storage for 14 days. Material and methods: Selection of a sample from the cryopreserved red blood cell store, thawing,
deglycerolization and determination of the volume, hematocrit, total hemoglobin, supernatant hemoglobin and pH on day
0, 7 and 14 post-thaw. Results: The mean volume was 282 ml, the supernatant hemoglobin 0,064 g/unit, Hematocrit 0,503,
total hemoglobin 40.8 g / unit, the osmolarity difference - 0.214 mOsm/Kg H2O and the microbiological control was negative
in all units. Discussion: Cryopreserved red blood cells have a long frozen storage period, but after thawing they have a short
storage period since initially, the process was in an open system. With the development of closed systems, the expiration date
of the product should be greater, but it is always subject to the validation of each center. The data show that the products
stored in our center, some up to 18 years old, are suitable for use and that the thawing and deglycerolization process is adequate.
Regarding the expiration period, although changes are observed in accordance with those described in other works, an
expiration time greater than 24 hours cannot be established because the supernatant hemoglobin after 7 days after defrosting
reaches levels higher than those allowed, remaining the rest of the quality parameters. Regarding the influence of frozen storage
time, previous studies indicate the absence of influence on the quality of the product, however in our study it is appreciated
that the oldest components present higher rates of hemolysis on day 14 after thawing, which could motivated by the previous
conservation period. Conclusions: The components obtained after thawing and deglycerolization meet the technical-legal
requirements of the European Union in all aspects. The expiration of these products in our center is 24 hours, having to look
for modifications in the preparation process to extend it. The previous freezing time does not seem to influence the intensity
of the damage to cellular metabolism in the early stages of post-thaw storage, although it does seem to negatively influence
the hemolysis rate in the late stages of post-thaw storage. These components, due to their high lifespan, constitute a strategic
reserve in the healthcare aspect, because they are of the O negative and O positive group and therefore easy to use, and in the
operational logistics aspect, since they allow the deployment of large quantities on the ground without the limitation of the
conservation time.
KEY WORDS: Cryopreserved red blood cells, storage injuries, quality, expiration, ACP 215.
186 New Technologies for Military Health (Part Two)
Crego-Vita DM, García-Cañas R., Huecas-Martínez M., Areta-Jiménez FJ.
SUMMARY: Introduction: since 2017 we have developed a 3D printing program in the Orthopedic Surgery and Traumatology
Unit of the Central Hospital of Defense «Gómez Ulla». The objective of this work is to present the preliminary
results obtained and the difficulties encountered in the use of 3D printing technology applied to military surgery. Material
and methods: impressions of surgical instruments usually used in orthopedic surgery were made, recording the model of
the printer used, the time required for printing it, the material used, as well as the quality of the product obtained. Subsequently,
the instruments were tested and their resistance was recorded. Results: twenty-seven surgical instrument devices
were created by additive manufacture using Polylactic Acid (PLA) and Acrylonitrile Butadiene Styrene (ABS) with two
3D printer models. The unit price of the devices printed in PLA did not exceed 2 euros, while that of those printed in
ABS was 3 euros. Average print times were similar on both 3D printer models. Failures were recorded in four devices printed
in PLA, while the models printed in ABS did not present failures and obtained better scores in the aspects surveyed.
Conclusions: using 3D printing, models of surgical instruments similar to those we use in surgical steel were obtained. The
production of these models is relatively fast, being these more resistant and reliable when using ABS as a printing material.
More studies are necessary in this research line to define the limits of 3D printing applied to military surgery.
KEYWORDS: 3D printing, war surgery, medical logistics, Polylactic Acid, Acrylonitrile Butadiene Styrene.
191 The epidemiology of mechanism of injury and their impact on the combat casualty injury severity
García-Cañas R., Navarro-Suay R., Rodríguez-Moro C.,Crego-Vita DM., Orellana-Gómez-Rico JA, Areta-Jiménez FJ.
SUMMARY: Introduction: The relationship between mechanisms of injury and injury severity has been widely documented
in studies carried out on the civilian population and on terrorist attacks, although these results are difficult to extrapolate to
the military environment, due to their inherent characteristics. The objective of this study was to analyze the distribution of
the mechanisms of injury and its relationship with injury severity in combat casualty. Material and methods: A retrospective,
descriptive and cross-sectional study was carried out on all patients injured by firearms or explosives treated in the Spanish
Role 2 deployed in Herat between 2005 and 2014. Results: A total of 911 combat casualties were analyzed in which the explosive
was the main mechanisms of injury in 64.76% of the cases, and the gunshot in 34.68%. The median mNISS scores in
casualties injured by gunshot 9 (IQR: 5-19) was higher than those injured by explosives 6 (IQR: 3-17). Furthermore, the
distribution of severity levels was different (p = 0.000) depending on the mechanisms of injury. Conclusions: Explosives were