Full Terms & Conditions of access and use can be found athttps://www.tandfonline.com/action/journalInformation?journalCode=ipec20
Prehospital Emergency Care
ISSN: 1090-3127 (Print) 1545-0066 (Online) Journal homepage: https://www.tandfonline.com/loi/ipec20
Prehospital Transfusion of Low-Titer O + WholeBlood for Severe Maternal Hemorrhage: A CaseReport
Ryan Newberry, C.J. Winckler, Ryan Luellwitz, Leslie Greebon, Elly Xenakis,William Bullock, Michael Stringfellow & Julian Mapp
To cite this article: Ryan Newberry, C.J. Winckler, Ryan Luellwitz, Leslie Greebon, Elly Xenakis,William Bullock, Michael Stringfellow & Julian Mapp (2019): Prehospital Transfusion of Low-TiterO + Whole Blood for Severe Maternal Hemorrhage: A Case Report, Prehospital Emergency Care,DOI: 10.1080/10903127.2019.1671562
To link to this article: https://doi.org/10.1080/10903127.2019.1671562
Accepted author version posted online: 24Sep 2019.
Submit your article to this journal
Article views: 11
View related articles
View Crossmark data
LTO+WB Transfusion for Maternal Hemorrhage
Prehospital Transfusion of Low-Titer O+ Whole Blood for Severe Maternal Hemorrhage:
A Case Report
Ryan Newberry, DO MPHa,b,*, C.J. Winckler, MD LP
b, Ryan Luellwitz, DOc, Leslie Greebon,
MDd, Elly Xenakis, MD
e, William Bullock, EMT-Pf, Michael Stringfellow, EMT-P
f, Julian
Mapp, MD MBA MPHa,b
aUS Army Institute of Surgical Research, JBSA Fort Sam Houston, TX 78234, USA
bDepartment of Emergency Health Sciences, University of Texas Health Science Center at San
Antonio, San Antonio TX 78229, USA cDepartment of Obstetrics & Gynecology, Dean Medical Group/SSM Health, Madison WI
53715, USA dDepartment of Pathology, University of Texas Health Science Center at San Antonio, San
Antonio TX 78229, USA eDepartment of Obstetrics and Gynecology, Division of Maternal Fetal Medicine, University of
Texas Health Science Center at San Antonio, San Antonio TX 78229, USA fSan Antonio Fire Department, San Antonio, TX 78207, USA
*Corresponding Author Ryan Newberry [email protected]
Abstract
Beginning in 2017, multiple stakeholders within the Southwest Texas Regional Advisory
Council for Trauma collaborated to incorporate cold-stored low-titer O RhD-positive whole
blood (LTO+WB) into all phases of their trauma system, including the prehospital phase of care.
Although the program was initially focused on trauma resuscitation, it was expanded to included
non-traumatic hemorrhagic shock patients that may benefit from whole blood resuscitation. We
report the case of a patient with severe maternal hemorrhage secondary to placenta accreta who
received a prehospital transfusion of LTO+WB. We believe this to be the first reported case of
post-partum hemorrhage resuscitated out of hospital with whole blood. This case highlights the
potential benefits of a prehospital whole blood program as well as the controversy surrounding a
LTO+WB program that includes females of childbearing age.
Keywords: whole blood transfusion, maternal hemorrhage, post-partum hemorrhage, low-titer
O+ whole blood transfusion
Accep
ted
Man
uscr
ipt
Introduction
Beginning in 2017, the San Antonio Medical Foundation, South Texas Blood and Tissue Center
(STBTC), UT Health San Antonio, University Health System, San Antonio Military Medical
Center, US Army Institute of Surgical Research and Southwest Texas Regional Advisory
Council for Trauma (STRAC) collaborated to incorporate cold-stored low-titer O RhD-positive
whole blood (LTO+WB) into all phases of their trauma system, including San Antonio Fire
Department (SAFD) ground ambulances in late 2018. In this program, LTO+WB is utilized due
to the limited O RhD-negative donor population needed to sustain an adequate O RhD-negative
blood inventory. Based on the demographics of south Texas, the stakeholders in this program
predicted that there would not be a sufficient population of type O RhD-negative donors to
sustain the necessary quantities of whole blood.1,2
Although the program was initially focused on
trauma resuscitation, the relevant stakeholders realized that non-traumatic hemorrhagic shock
patients, including pregnant women, may benefit from this program.
Prescreened LTO+WB is a safe and effective solution for emergency transfusion that has
recently been approved by the American Association of Blood Banks (AABB) based on the
recommendations of a joint Trauma Hemostasis and Oxygen Research (THOR)-AABB working
group.3-5
An alternative modality to the balanced ratio (1:1:1) of blood component-based
resuscitation, LTO+WB has proven benefits compared to component therapy and ABO group-
specific approaches.1-3
One of the main disadvantages of component therapy mitigated through
the use of whole blood is overcoming the dilute blood mixture largely attributed to necessary
addition of anticoagulants and additive solution. Previous research has also suggested that
resuscitation with whole blood overcomes the thrombocytopenia that typically accompanies
Accep
ted
Man
uscr
ipt
transfusion with component therapy.3 The current literature suffers from a paucity of prospective
patient outcome data concerning whole blood transfusion. However, multiple studies based on
retrospective data have suggested improved 30-day survival after resuscitation with whole
blood.6 Several recent articles have also suggested that whole blood provides the optimal
physiologic replacement and that LTO+WB is likely the preferred product for prehospital and
emergency department resuscitation.1-3
The SAFD Emergency Medical Services (EMS) division is comprised of 35 full-time paramedic
ambulances and six paramedic officers responding annually to approximately 168,000 EMS
responses.7 The paramedic officers, known as medic officers (MOFs), are EMS lieutenants who
have the responsibility and oversight of the EMS paramedic ambulances in their geographic
sector. The MOFs are available 24-hours per day and are dispatched for operational and logistic
needs of their assigned crews.2,7
Currently one unit of LTO+WB is carried on each of two
special operations paramedic ambulances and six MOF response vehicles. The LTO+WB is
transported in Pelican BioThermal Credo Golden HourTM
Mobile Series 4 2L EMT coolers.
These transport coolers are a combination of a temperature controlled medical transport bag and
a removable thermal isolation chamber (TIC pack) that are rated to protect blood products at a
temperature range of 2-8 degrees Celsius for a period of 48-hours per the manufacturer.8 This
was independently validated by STBTC and STRAC prior to implementation of the prehospital
LTO+WB program.9
The LTO+WB is received by SAFD directly from STBTC for the 0-14 shelf-life days. Each
SAFD EMS unit with blood transfusion capability utilizes a two TIC pack rotation system for the
Accep
ted
Man
uscr
ipt
transport of the LTO+WB. At the beginning of each 24-hour shift, unused LTO+WB is rotated
from its current Golden HourTM
cooler and placed into a conditioned cooler for the next 24-hour
shift. At shelf-life day number 14, an unused LTO+WB unit is exchanged at STBTC for a fresh
LTO+WB unit and subsequently taken to a Level I trauma center for immediate use in trauma
resuscitation.
SAFD EMS units utilize a physiologic-based criterion for the decision of when to transfuse
LTO+WB to patients experiencing hemorrhagic shock of either medical or trauma etiology
(Figure 1, Figure 2). SAFD deploys the QinFlowTM
Warrior lite IV fluid warmer and two
pressure systems to transfuse LTO+WB, the VentlabTM
disposable pressure infuser and the
Braun Y-type blood set with an inline handpump (Figure 3). Together, these pressure systems
consistently allow transfusions of 500 mL of whole blood warmed to 38 degrees Celsius to be
completed in approximately 5 minutes.10
In addition to the EMS patient care report that is
generated after each EMS response, a triplicate prehospital blood transfusion record is completed
by the paramedics with two copies being issued to the receiving emergency department (Figure
4). Subsequently, the prehospital blood transfusion forms are distributed to the patient’s
emergency department health record and the receiving hospital’s pathology laboratory.
Here we report the case of a patient with severe maternal hemorrhage secondary to placenta
accreta who received a prehospital transfusion of LTO+WB. This case highlights the potential
benefits of a prehospital whole blood program as well as the controversy surrounding a
LTO+WB program that includes females of childbearing age. The University of Texas Health
Science Center San Antonio Emergency Health Sciences Office of the Medical Director
Accep
ted
Man
uscr
ipt
(UTHSCSA OMD) maintains a whole blood registry as part of their ongoing prehospital whole
blood QA/QI program. Our team utilized the CAse REport (CARE) guidelines to report this
case, and the patient provided her informed consent.11
Case Report
The San Antonio Fire Department was called to the home of a 27-year-old, gravida 4 para 3
pregnant female at 35-weeks gestation, for an “OBGYN” call at 0018 hours. Her pregnancy was
complicated by known placenta previa with possible abnormally adherent placenta accreta.
When calling 9-1-1, it was reported that the patient had been vaginally bleeding for about twenty
minutes. The SAFD EMS unit arrived to the residence of the caller at 0026 hours and noted a
trail of blood leading to a second-floor bathroom. They subsequently found the patient sitting in
a pool of blood inside a bathtub. The paramedics estimated the amount of blood loss to be greater
than 500 mL. The patient was conscious, “lethargic,” and not speaking to anyone. Their primary
assessment of the patient demonstrated normal work of breathing, pale cool skin, moderate
vaginal bleeding and the monitor displayed no quantified blood pressure on initial usage.
The patient was assisted to a stair chair and rapidly extricated to the ambulance, where
intravenous (IV) access was obtained with a 16 gauge IV catheter in her right antecubital vein.
Initial vital signs at 0037 hours were a pulse of 85 beats per minute (bpm), blood pressure of
68/45 mmHg, respiratory rate of 14 and shock index of 1.3. At the same time, transfusion of 500
mL of warmed LTO+WB was initiated. The patient was then emergently transported to the
nearest community hospital. While en route vital signs were a pulse of 86 bpm, blood pressure of
84/55 mmHg, respiratory rate of 16 and shock index of 1.0. Placement of a second IV catheter
Accep
ted
Man
uscr
ipt
was attempted but unsuccessful. Electrocardiogram (ECG) was also obtained and demonstrated a
normal sinus rhythm.
The patient arrived at the community hospital’s emergency department at 0055 with ongoing
resuscitation with LTO+WB. Her vital signs at 0055 were a pulse of 97 bpm, blood pressure of
100/56 mmHg, respiratory rate of 18, oxygen saturation (O2) 99% and shock index of 1.0. Initial
serum labs revealed a hemoglobin of 9.5 g/dL and hematocrit of 28.0%. Her chemistry panel and
coagulation studies were within normal limits. Pelvic examination performed by the emergency
physician noted coagulated blood in the vaginal vault with minimal active bleeding. A fetal heart
rate was found to be 140 bpm. The remainder of her emergency department course included
administration of 1.5 grams of cefuroxime, 30 mL of citric acid/sodium citrate and 1000 mL of
Lactated Ringers solution. The patient was then transferred to the operating suite for emergent
cesarean section.
The patient had an emergent cesarean delivery followed by an immediate hysterectomy without
complications. During the operation, she received an additional two units of packed red blood
cells (PRBC). Blood loss was estimated to be 1000 mL. The mother was subsequently found to
be of the blood type A RhD-positive. A viable male infant of the blood type O RhD-positive
was delivered with 1- and 5-minute APGAR scores of 7 and 8, respectively. The infant was
admitted to the neonatal intensive care unit (NICU) immediately after delivery. The patient’s
postoperative course was remarkable for a serum hemoglobin 5.0 g/dL and hematocrit of 16%.
She was subsequently transfused an additional two units of PRBCs. The remainder of her
Accep
ted
Man
uscr
ipt
hospital course was unremarkable. She was discharged from the hospital on postoperative day
three. The infant was discharged from the NICU approximately two weeks later.
Discussion
Maternal hemorrhage remains a leading cause of maternal morbidity and mortality worldwide,
accounting for 11.4% of maternal deaths in the United States between 2006-2010.12
To further
improve the quality of maternal hemorrhage management, the National Partnership for Maternal
Safety recommended that U.S. birthing facilities partner with local transfusion services to ensure
the rapid availability of blood products and published hospital protocols that indicated blood
component therapy as a critical aspect of postpartum hemorrhage management.12,13
Our
prehospital LTO+WB program is an extension of this intention to treat maternal hemorrhage
early and decisively. However, there are risks associated with exposing females of childbearing
age to LTO+WB. In particular is the risk of maternal RhD alloimmunization. RhD
alloimmunization occurs when a woman with RhD-negative (Rh-) blood is exposed to RhD-
positive (Rh+) blood cells, leading to the formation of antibodies against RhD. Women of
childbearing age can be exposed to Rh+ blood cells through fetal-maternal hemorrhage as well as
blood product administration, including LTO+WB.14
During the first seven months of the SAFD LTO+WB initiative, there were 95 transfusions of
LTO+WB. Females accounted for 28 cases, of which 16 were women less than 40 years old.
After extrapolating this data from our whole blood registry, our team projects that the SAFD will
transfuse a total of 23 female patients under age 40 per year over a 12-month period. This cohort
of 23 patients includes both Rh+ and Rh
- females. Using a 15% incidence of Rh
- individuals in
Accep
ted
Man
uscr
ipt
the overall population, the SAFD ground ambulance whole blood initiative may expose
approximately four Rh- young females to LTO+WB annually. However, the demographics of the
greater San Antonio metropolitan area suggests that 15% is an overestimate of the prevalence of
Rh- blood types in our patient population. For example, one of our local trauma centers
conducted a 30-month review of their massive transfusion protocol (MTP) recipients and found
that only 6.3% of the female MTP recipients were Rh-.1
Exposure to Rh+ blood cells does not directly translate to alloimmunization. Recent studies of
hospitalized patients observed that the alloimmunization rate of exposed individuals is between
11.5% and 30.4%.15-18
This rate is considerably lower than the often cited 80 to 92%
alloimmunization rate derived from two small studies of healthy volunteers conducted in 1970
and 1981 respectively.19,20
Assuming a 30.4% conversion rate, the SAFD ground ambulance
program whole blood program would lead to one woman of childbearing age undergoing RhD
alloimmunization annually.
However, if we consider alloimmunization the endpoint when considering the adverse effects of
transfusing LTO+WB to a Rh- young woman, several assumptions have to be made. One, she
desires future pregnancies. Two, she will conceive with a male partner who has an Rh+ blood
type. Three, the prevention of alloimmunization via administration of Rh Immune globulin
(RhIg) or red blood cell exchange was unsuccessful or not plausible after exposure to the RhD
antigen. Four, the affected fetus will have severe hemolytic disease and fetal blood transfusions
will be ineffective.
Accep
ted
Man
uscr
ipt
The development of anti-RhD antibodies in the Rh- female of childbearing age is a serious
adverse event that may lead to significant complications in future pregnancies. However, it must
be appropriately weighed against the dangers of withholding potentially life-saving early
resuscitation to patients in hemorrhagic shock. Therefore, an LTO+WB program may be the only
way to provide a balanced, blood-based, resuscitation to patients in the prehospital phase of care
that are in hemorrhagic shock.
RhD alloimmunization has been successfully prevented with the administration of Rho(D)
immune globulin, also known as RhoGAM (RhIg). A standard pre-natal or post-natal dose of
RhIg consists of a single 300 microgram (ug) vial and is administered intravenously or
intramuscularly, depending on the manufacturer. Each 300 ug vial effectively prevents
alloimmunization after exposure to 15 mL of Rh+ PRBCs or 30 mLs of Rh+ whole blood.
Typically, Rh- women receive anti-D immunoglobulin within 72 hours after suspected fetal-
maternal hemorrhage, miscarriage, ectopic pregnancy and delivery to prevent the formation of
antibodies against RhD.21-23
Maternal RhD alloimmunization can have significant implications in
subsequent pregnancies, including hemolytic disease of the fetus.14
With the risk of maternal
RhD alloimmunization, it is prudent to evaluate if women of childbearing age should receive
LTO+WB.
For women who receive LTO+WB that are subsequently found to be Rh-, it is recommended that
the trauma services within receiving hospitals create a protocol to determine RhIg candidacy. At
one of our local trauma centers, a protocol has been devised where the trauma service consults
pathology and obstetrics services within 24 hours of LTO+WB transfusion to enable counseling
Accep
ted
Man
uscr
ipt
of the patient on potential alloimmunization and possible candidacy of RhIg administration.1
Determination of RhIg administration candidacy is based on the patient’s desire of future
pregnancy, clinical condition, prognosis and the volume of transfused LTO+WB.14
RhIg
administration may be considered in a patient who has received less than 20% of their total blood
volume (TBV) during transfusion of LTO+WB. If the volume of LTO+WB transfused is less
than 20% TBV with other favorable clinical characteristics, then RhIg is dosed at 18-20 ug per
mL of transfused red cells to prevent isoimmunization. A standard whole blood unit will contain
approximately 250 mL of red blood cells. Therefore, due to this large volume of exposure,
dosing to cover the mLs of RBCs transfused results in large doses of RhIg and thus should be
divided and administered over several days via intravenous infusion only. If the volume of
transfusion exceeds 20% TBV of the patient, RhIg administration is not usually pursued since
there is considerable risk of inducing splenic sequestration and extravascular hemolysis. In larger
volume transfusion events (greater than 20% TBV), red blood cell exchange(s) may be
considered to remove antigenic stimulus. In addition, it is recommended for follow-up testing at
three, six and twelve months to determine if alloimmunization occurred.1,21-23
Conclusion
We present the case of a 27-year-old female with severe hemorrhage that was successfully
treated with prehospital low-titer O Rh-positive whole blood. The development of anti-RhD
antibodies in the RhD-negative female of childbearing age is a serious adverse event that may
lead to significant complications in future pregnancies, and it must be appropriately weighed
against the dangers of withholding potentially life-saving early resuscitation to patients in
hemorrhagic shock. We conclude that due to the low risk of maternal RhD alloimmunization
Accep
ted
Man
uscr
ipt
EMS systems should consider including females of childbearing age into protocols where only O
Rh-positive blood products are available.
Prior Presentations
none
Funding/Conflict of Interests
none
Author contributions
RN, RL, and JM drafted the original manuscript. All authors critically reviewed, contributed and
edited the case report. RN takes responsibility for the paper as a whole.
Disclaimer
The views expressed in this article are those of the author(s) and do not reflect the official policy
or position of the city of San Antonio, the U.S. Army Medical Department, Department of the
Army, Department of Defense, or the U.S. Government.
References
1. McGinity AC, Zhu CS, Greebon L, et al. Prehospital low-titer cold-stored whole blood: Philosophy for ubiquitous utilization of O-positive product for emergency use in hemorrhage due to injury. J Trauma Acute Care Surg 2018;84:S115-S9. 2. Zhu CS, Pokorny DM, Eastridge BJ, Nicholson SE, et al. Give the trauma patient what they bleed, when and where they need it: establishing a comprehensive regional system of resuscitation based on patient need utilizing cold-stored, low-titer O+ whole blood. Transfusion 2019;59:1429-1438. 3. Weymouth W, Long B, Koyfman A, Winckler C. Whole blood in trauma: a review for emergency clinicians. J Emerg Med 2019;56(5):491-498. 4. Press release: emergency release low titer O whole blood is now permitted by AABB standards. In: The trauma hemostasis and oxygen research (THOR) network; 2018. https://rdcr.org/press-release-emergency-release-low-titer-group-o-whole-blood-now-permitted-aabb-standards/. 5. American Association of Blood Banks (AABB). Standards for blood banks and transfusion services. Bethesda, MD: AABB; 2018. 6. Fisher AD, Miles EA, Cap AP, Strandenes G, et al. Tactical damage control resuscitation. Mil Med 2015;180:869-75. 7. San Antonio Fire Department. City of San Antonio Fire Department Annual Report 2018. San Antonio, TX, 2018. [cited 04Aug2019]. Available from: http//www.sanantonio.gov 8. Pelican BioThermal. Golden HourTM Medic Series 4. Plymouth, MN. [cited 12Aug2019]. Available from www.pelicanbiothermal.com 9. Kumar, S. Project to qualify Level I helicopter blood transport box operational qualification report. MaxQ Research LLC. MaxQ Project No TV1101007. Project end date 30Nov2017. Document not reproducible with the written authorization of MaxQ Research LLC.
Accep
ted
Man
uscr
ipt
10. QinFlow Incorporated. The warrior modular system. North American Headquarters, Plano, TX. [cited 12Aug2019]. Available from www.quinflow.com 11. Gagnier JJ, Kienle G, Altman DG, et al. The CARE guidelines: consensus-based clinical case report guideline development. J Clin Epidemiol 2014;67:46-51. 12. Butwick AJ, Goodnough LT. Transfusion and coagulation management in major obstetric hemorrhage. Curr Opin Anaesthesiol 2015;28:275-84. 13. Alexander JM, Sarode R, McIntire DD, Burner JD, Leveno KJ. Whole blood in the management of hypovolemia due to obstetric hemorrhage. Obstetrics and gynecology 2009;113:1320-6. 14. Prevention of Rh D alloimmunization. Practice Bulletin No. 181. American College of Obstetricians and Gynecologists. Obstet Gynecol 2017;130:e57–70. 15. Frohn C, Dumbgen L, Brand JM, Gorg S, Luhm J, Kirchner H. Probability of anti-D development in D- patients receiving D+ RBCs. Transfusion 2003;43:893-8. 16. Yazer MH, Triulzi DJ. Detection of anti-D in D- recipients transfused with D+ red blood cells. Transfusion 2007;47:2197-201. 17. Gonzalez-Porras JR, Graciani IF, Perez-Simon JA, et al. Prospective evaluation of a transfusion policy of D+ red blood cells into D- patients. Transfusion 2008;48:1318-24. 18. Tchakarov A, Hobbs R, Bai Y. Transfusion of D+ red blood cells to D- individuals in trauma situations. Immunohematology 2014;30:149-52. 19. Gunson HH, Stratton F, Cooper DG, Rawlinson VI. Primary immunization of Rh-negative volunteers. British medical journal 1970;1:593-5. 20. Urbaniak SJ, Robertson AE. A successful program of immunizing Rh-negative male volunteers for anti-D production using frozen/thawed blood. Transfusion 1981;21:64-9. 21. Nester T, Rumsey D, Howell C, Gilligan D, et al. Prevention of immunization to D+ red blood cells with red blood cell exchange and intravenous Rh immune globulin. Transfusion 2004;44(12):1720-3. 22. Anderson B, Shad A, Gootenberg J, Sandler S. Successful prevention of post-transfusion Rh alloimmunization by intravenous Rho (D) immune globulin (WinRho SD). Am J Hematol 1999;60(3):245-7. 23. Ayache S, Herman J. Prevention of D sensitization after mismatched transfusion of blood components: toward optimal use of RhIG. Transfusion 2008;48(9):1990-9. Table 1: Prehospital, Emergency Department Hospital Course vital signs, laboratory results and interventions
Time Intervention Heart Rate
Blood Pressure
Lab Fluid
00:18 Public Safety Answering Point
0:18 SAFD EMS Units Dispatched
00:26 SAFD Paramedic Ambulance On-Scene
00:28 Paramedic 85 Automated
Accep
ted
Man
uscr
ipt
Primary Assessment
Cuff not able to detect
00:30 SAFD Ladder Company On-Scene
00:32 16 g IV Right AC
00:33 Patient extricated from residence with stair chair
00:35 SAFD Medic Officer On-Scene
LTO+WB Capable
00:37 Cardiac Monitor ECG: NSR 85 68/45
00:37 Decision to transfuse 1 U LTO+WB
1 U LTO+WB
00:40 Cardiac Monitor ECG: NSR 85
00:41 Cardiac Monitor 86 84/55
00:42 Transport to Emergency Department
Completed LTO+WB transfusion en route
00:50 Arrival at Emergency Department
00:55 Emergency Department
97 100/56
Emergency Department
Cefuroxime 1.5 gm Citric Acid 30 mL
LR 1000 mL
01:01 Emergency Department
CBC: Hgb 9.5, HCT 29.7, WBC 26.1, Plt 262 Chem: Na 137, K 3.9, Cl 104, CO2 20, BUN 9, Cr 0.5, Glu 124, Ca 1.01
01:07 Patient Cesarean 2 U O-
Accep
ted
Man
uscr
ipt
discharged from ED to OR
delivery Hysterectomy
PRBC
Post-operative Course
Patient discharged on January 10 Male infant admitted to NICU, discharged after 14 day course
Range: 81-97
Range: 92-114 SBP
01/08 CBC: Hgb 5.9, HCT 17.9, WBC 9.7, PLT 148 01/09 CBC: Hgb 7.1, HCT 21.1, WBC 9.6, PLT 163
2 U O- PRBC
Accep
ted
Man
uscr
ipt
Figure 1. San Antonio Fire Department Low Titer O+ Whole Blood Trauma Clinical Operating Guideline
Accep
ted
Man
uscr
ipt
Figure 2. San Antonio Fire Department Low Titer O+ Whole Blood Medical Clinical Operating Guideline
Accep
ted
Man
uscr
ipt
Figure 3. San Antonio Fire Department Medic Officer transfusing low titer O+ whole blood to a trauma patient.
Accep
ted
Man
uscr
ipt
Figure 4. Southwest Texas Regional Advisory Council prehospital blood product transfusion record.
Accep
ted
Man
uscr
ipt