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30 Blood Transfusion andTraumatic Brain Injury
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55. Robertson CS, et al. Effect of erythropoietin and transfusion threshold on neurological recovery after traumatic brain injury: a randomized clinical trial. JAMA. 2014;312(1):36–47.
56. Vedantam A, et al. Progressive hemorrhagic injury after severe traumatic brain injury: effect of hemoglobin transfusion thresh­olds. J Neurosurg. 2016;125(5):1229–34.
57. McIntyre LA, etal. Effect of a liberal versus restrictive transfu­sion strategy on mortality in patients with moderate to severe head injury. Neurocrit Care. 2006;5(1):4–9.
58. Carr KR, et al. Association between relative anemia and early functional recovery after severe traumatic brain injury (TBI). Neurocrit Care. 2016;25(2):185–92.
59. Yamal JM, etal. Association of transfusion red blood cell stor­age age and blood oxygenation, long-term neurologic outcome, and mortality in traumatic brain injury. J Trauma Acute Care Surg. 2015;79(5):843–9.
60. Ruel-Laliberte J, etal. Effect of age of transfused red blood cells on neurologic outcome following traumatic brain injury (ABLE­tbi Study): a nested study of the Age of Blood Evaluation (ABLE) trial. Can J Anaesth. 2019;66(6):696–705.
61. Dutzmann S, et al. On the value of routine prothrombin time screening in elective neurosurgical procedures. Neurosurg Focus. 2012;33(5):E9.
62. West KL, Adamson C, Hoffman M.Prophylactic correction of the international normalized ratio in neurosurgery: a brief review of a brief literature. J Neurosurg. 2011;114(1):9–18.
63. American Society of Anesthesiologists Task Force on Perioperative Blood, M. Practice guidelines for periopera­tive blood management: an updated report by the American Society of Anesthesiologists Task Force on Perioperative Blood Management*. Anesthesiology. 2015;122(2):241–75.
64. Kozek-Langenecker SA, et al. Management of severe peri­operative bleeding: guidelines from the European Society of Anaesthesiology. Eur J Anaesthesiol. 2013;30(6):270–382.
65. Anglin CO, et al. Effects of platelet and plasma transfusion on outcome in traumatic brain injury patients with moderate bleeding diatheses. J Neurosurg. 2013;118(3):676–86.
66. Zhang LM, etal. Increased transfusion of fresh frozen plasma is associated with mortality or worse functional outcomes after severe traumatic brain injury: a retrospective study. World Neurosurg. 2017;104:381–9.
67. Leeper CM, et al. Overresuscitation with plasma is associated with sustained brinolysis shutdown and death in pediatric trau­matic brain injury. J Trauma Acute Care Surg. 2018;85(1):12–7.
68. Wohlauer MV, et al. Early platelet dysfunction: an unrecog­nized role in the acute coagulopathy of trauma. J Am Coll Surg. 2012;214(5):739–46.
69. Davis PK, et al. Platelet dysfunction is an early marker for traumatic brain injury-induced coagulopathy. Neurocrit Care. 2013;18(2):201–8.
70. Castellino FJ, etal. Traumatic brain injury causes platelet adenos­ine diphosphate and arachidonic acid receptor inhibition indepen­dent of hemorrhagic shock in humans and rats. J Trauma Acute Care Surg. 2014;76(5):1169–76.
71. Guillotte AR, et al. Effects of platelet dysfunction and platelet transfusion on outcomes in traumatic brain injury patients. Brain Inj. 2018;32(13–14):1849–57.
72. Furay E, etal. Goal-directed platelet transfusions correct platelet dysfunction and may improve survival in patients with severe trau­matic brain injury. J Trauma Acute Care Surg. 2018;85(5):881–7.
73. Practice parameter for the use of fresh-frozen plasma, cryopre­cipitate, and platelets. Fresh-Frozen Plasma, Cryoprecipitate, and Platelets Administration Practice Guidelines Development Task Force of the College of American Pathologists. JAMA. 1994;271(10):777–81.
74. Estcourt LJ, etal. Guidelines for the use of platelet transfusions. Br J Haematol. 2017;176(3):365–94.
75. Goobie SM, Haas T. Bleeding management for pediat­ric craniotomies and craniofacial surgery. Paediatr Anaesth. 2014;24(7):678–89.
76. Chan KH, Mann KS, Chan TK.The signicance of thrombocyto­penia in the development of postoperative intracranial hematoma. J Neurosurg. 1989;71(1):38–41.
77. Downey DM, etal. Does platelet administration affect mortality in elderly head-injured patients taking antiplatelet medications? Am Surg. 2009;75(11):1100–3.
78. Bachelani AM, et al. Assessment of platelet transfusion for reversal of aspirin after traumatic brain injury. Surgery. 2011;150(4):836–43.
79. Briggs A, et al. Platelet dysfunction and platelet transfusion in traumatic brain injury. J Surg Res. 2015;193(2):802–6.
80. Holzmacher JL, etal. Platelet transfusion does not improve out­comes in patients with brain injury on antiplatelet therapy. Brain Inj. 2018;32(3):325–30.
81. Jehan F, etal. Is there a need for platelet transfusion after trau­matic brain injury in patients on P2Y12 inhibitors? J Surg Res. 2019;236:224–9.
82. Leong LB, David TK.Is platelet transfusion effective in patients taking antiplatelet agents who suffer an intracranial hemorrhage? J Emerg Med. 2015;49(4):561–72.
83. Jokar TO, et al. Ratio-based resuscitation in trauma patients with traumatic brain injury: is there a similar effect? Am Surg. 2016;82(3):271–7.
84. Wong H, Curry N, Stanworth SJ.Blood products and procoagu­lants in traumatic bleeding: use and evidence. Curr Opin Crit Care. 2016;22(6):598–606.
85. Shibahashi K, et al. Initial results of empirical cryoprecipitate transfusion in the treatment of isolated severe traumatic brain injury: use of in-house-produced cryoprecipitate. Neurol Med Chir (Tokyo). 2019;59(10):371–8.
86. Kozek-Langenecker SA, et al. Management of severe peri­operative bleeding: guidelines from the European Society of Anaesthesiology: rst update 2016. Eur J Anaesthesiol. 2017;34(6):332–95.
87. New HV, etal. Guidelines on transfusion for fetuses, neonates and older children. Br J Haematol. 2016;175(5):784–828.
88. Shakur H, et al. Antibrinolytic drugs for treating primary postpartum haemorrhage. Cochrane Database Syst Rev. 2018;2:Cd012964.
89. Weng S, et al. Effect of tranexamic acid in patients with trau­matic brain injury: a systematic review and meta-analysis. World Neurosurg. 2019;123:128–35.
90. Sandri A, etal. Perioperative intravenous tranexamic acid reduces blood transfusion in primary cementless total hip arthroplasty. Acta Biomed. 2019;90(1-s):81–6.
91. Haghighi M, etal. Does tranexamic acid reduce bleeding during femoral fracture operation? Arch Bone Jt Surg. 2017;5(2):103–8.
92. Wang Y, Liu S, He L.Prophylactic use of tranexamic acid reduces blood loss and transfusion requirements in patients undergo­ing cesarean section: a meta-analysis. J Obstet Gynaecol Res. 2019;45(8):1562–75.
93. Roberts I, etal. The CRASH-2 trial: a randomised controlled trial and economic evaluation of the effects of tranexamic acid on death, vascular occlusive events and transfusion requirement in bleeding trauma patients. Health Technol Assess. 2013;17(10):1–79.
94. Perel P, et al. CRASH-2 (Clinical Randomisation of an Antibrinolytic in Signicant Haemorrhage) intracranial bleed­ing study: the effect of tranexamic acid in traumatic brain injury-
-a nested randomised, placebo-controlled trial. Health Technol Assess. 2012;16(13):iii–xii, 1–54.
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J. V. Montoya-Gacharna and S. Kendale
95. Roberts I, et al. Tranexamic acid for signicant traumatic brain injury (The CRASH-3 trial): statistical analysis plan for an inter­national, randomised, double-blind, placebo-controlled trial. Wellcome Open Res. 2018;3:86.
96. Sprigg N, et al. Tranexamic acid for hyperacute primary IntraCerebral Haemorrhage (TICH-2): an international ran­domised, placebo-controlled, phase 3 superiority trial. Lancet. 2018;391(10135):2107–15.
97. Mahmood A, Roberts I, Shakur H.A nested mechanistic sub-study into the effect of tranexamic acid versus placebo on intracranial haemorrhage and cerebral ischaemia in isolated traumatic brain injury: study protocol for a randomised controlled trial (CRASH-3
Trial Intracranial Bleeding Mechanistic Sub-Study [CRASH-3 IBMS]). Trials. 2017;18(1):330.
98. Morte D, etal. Tranexamic acid administration following head trauma in a combat setting: does tranexamic acid result in improved neurologic outcomes? J Trauma Acute Care Surg. 2019;87(1):125–9.
99. Ebrahimi P, etal. Intravenous tranexamic acid for subdural and epi­dural intracranial hemorrhage: randomized, double-blind, placebo­controlled trial. Rev Recent Clin Trials. 2019;14(4):286–91.
100. Lombardo S, etal. Factor VIIa administration in traumatic brain injury: an AAST-MITC propensity score analysis. Trauma Surg Acute Care Open. 2018;3(1):e000134.
Transfusion-Related
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Immunomodulation inRelation toPerioperative Infection/Cancer: Biology, Evidence, andControversy inTransfusion
AtishPatel andBruceD.Spiess
31
Background
Red blood cell (RBC) transfusions have evolved to be one of the most common medical interventionsa in the United States and are given to approximately three to four million patients each year (14+ million units per year) [1, 2]. The number of RBC transfusions peaked in 2012–2013 with sub­sequent years demonstrating some decrease. Causes put forth by blood bankers for this decrease include the 2008– 2009 economic downturn, but it has persisted and expanded since the economy has recovered. Far more realistic is the appreciation by medicine that transfusion is associated with (causes) adverse outcomes. RBC transfusion has long been known to carry signicant risks. However, the transfusion decision is rarely an in-depth risk-benet analysis.
Historically, focus has been on ABO-Rh compatibility, virus, pathogen avoidance, and whether blood banking was able to meet the demands created by expanding, evermore complex medical/surgical care in an aging population. The rst reports of serious hepatitis transmission occurred in 1947, yet the use of transfusion grew until the human immu­nodeciency virus transfusion crisis [3]. The viral risks exceeded 10–40% seroconversion in some places, but it was not until the late 1980s that critical steps were taken to reduce the risks to below 1/1–4,000,000units infused [3, 4].
Today, blood transfusion still has many serious side effects, which are often under-appreciated by physicians. A
The work contained within is solely the author’s own and each has con­tributed from conception through writing and reviewing.
A. Patel (*) Vanderbilt University Medical Center, Department of Anesthesiology, Nashville, TN, USA e-mail: atish.patel@vumc.org
B. D. Spiess University of Florida Health, Gainesville, FL, USA e-mail: bspiess@anest.u.edu
contemporary list of transfusion risks includes (in order of frequency): non-hemolytic febrile reactions (higher in non­leukoreduced blood products), allergic reactions (not includ­ing anaphylaxis), transfusion-associated circulatory overload, metabolic toxicities and derangements, transfusion­related immunomodulation (TRIM), transfusion-associated lung injury (TRALI), post-transfusion purpura, graft-versus­host disease, transfusion-transmitted viruses, parasites and bacteria, and anaphylaxis, among others [5–7]. It can be argued that TRIM is present to some degree in all patients who have received an allogeneic transfusion and therefore should be listed as the number one complication of transfu­sion. TRALI, allergic reactions, non-hemolytic febrile reac­tions, graft-versus-host disease, and anaphylaxis are ultimately immune-mediated, therefore all are TRIM.TRIM has also become synonymous with increased nosocomial infection and/or cancer recurrence.
TRALI is widely noted to be the most frequent cause of death after transfusion [8]. The contribution of TRIM to the morbidity and mortality of hospitalized critically ill patients may well outdistance the effects of TRALI in leading to bad outcomes. TRALI is itself a result of TRIM, and TRIM hap­pens near universally. The decision to transfuse a patient is most often made based upon a perceived risk (fear) of decreased oxygen-carrying capacity imputed by not trans­fusing. Many academic surgical and medical societies have guidelines regarding appropriate RBC transfusion triggers (usually a range of hemoglobin or hematocrit). Medicine has underdeveloped monitoring capabilities for tissue oxygen delivery/utilization; thus the anxiety leading to transfusion behavior is based on perceived risk often with little data. We believe that few who make the transfusion decision fully appreciate the literature regarding TRIM and that such knowledge, if acquired, could well promote caution when ordering an RBC transfusion. This review will examine con­troversial/contradictory literature as well as the biologic mechanisms of TRIM.In the end, the review will question
© Springer Nature Switzerland AG 2021 C. S. Scher et al. (eds.), Essentials of Blood Product Management in Anesthesia Practice,
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the ethical/quality control point: Is unnecessary RBC trans­fusion an avoidable human error in medicine?
History ofTRIM
There is strong evidence of TRIM-related effects on transfu­sion recipients. Increased rates of tumor recurrence are noted in transfusion versus non-transfusion patients, as are nosoco­mial infections. Because a patient does not manifest a noso­comial infection does not in itself mean that he/she has not experienced some level of TRIM.Nosocomial infections kill and cost billions of dollars with per patient cost of over $50– 75,000 USD in complications [9]. Because over 60% of ICU-treated patients receive a blood transfusion, the rela­tionship between transfusion and the current ICU bacteria may be related.
TRIM was rst embraced as a concept in the 1970s with orthotropic renal transplantation. Opelz etal. [10] conducted a prospective, multicenter study that found kidney organ sur­vival rates to be higher in patients who received allogeneic blood transfusions (ABTs; 90% vs 82%, P = 0.02). The results pointed to a dose-dependent relationship between RBC transfusion and immunosuppression. Improved overall survival rate at a 5-year follow-up, in addition to animal and observational studies, showed similar results, which led to widespread and liberal use of ABTs, especially with trans­plantation in order to decrease graft-versus-host complica­tions [10–14]. At times, patients were transfused when their hemoglobin was in excess of 10gm/dL solely for the purpose of creating immunosuppression. In the late 1980s, in addi­tion to organ transplants, transfusions were liberally admin­istered to women experiencing recurrent spontaneous abortion (thought to be an immune-related maternal attack on the fetus) [15]. Today, those who argue against TRIM and transfusion dismiss or ignore these historical facts. Some explain the renal allograft data as due to a time when alloge­neic blood was not leukoreduced. The effect of leukoreduc­tion will be discussed later. Notably, leukoreduction may lessen but does not eliminate TRIM.
The practice of using transfusion as a way to intentionally immune inhibit a recipient ended with two events: with the onset of the AIDS and hepatitis C epidemics along with the advent of cyclosporine immunosuppressives and other mod­ern immunosuppressive agents. Transfusion as a medical technique to intentionally immunosuppress came to a halt.
Cancer Recurrence
After the benecial immunosuppressive effect of transfusion was recognized, Gantt, in 1981 [16], suggested an associa­tion between transfusion and increased cancer recurrence,
raising concern that the outcome for patients undergoing curative surgery for a malignancy might be worsened. The reasoning was, if transfusion downregulated the recipient’s immune system, it might also enhance tumor growth and the implantation/growth of metastases. Since then, multiple observational studies, randomized controlled trials (RCTs), and meta-analyses have been published pointing toward higher rates of cancer recurrence, especially colorectal, blad­der, and most recently hematopoietic/leukemic cancers [17,
18, 37–43].
The focus of transfusion then shifted in the late 1980s when several researchers began to suggest that some of the adverse patient outcomes that had been attributed to intractable disease and comorbid conditions were in fact complications of transfusion therapy. This led to retrospective and prospective observational studies, in addi­tion to animal studies in the following decade, which impli­cated TRIM as causing higher postoperative infection rates. Neil Blumberg compiled data from these studies and found that patients receiving perioperative transfusion (compared with those not receiving transfusion) had a higher risk of developing postoperative bacterial infection (as much as 200–1000% higher).
Much needed RCTs to verify this surprising evidence soon followed. Several small- to medium-sized RCTs in the early 1990s containing between 50 and 500 patients were conducted that showed higher postoperative infections in orthopedic, colorectal, and cardiac surgeries [17, 18]. In 1998, an association between non-leukoreduced ABTs and short-term overall mortality (up to 3 months post- transfusion) was described by van de Watering etal. [19] That study com­pared cardiac surgery patients receiving non-white blood cell (WBC)-reduced versus WBC-reduced allogeneic RBCs [19]. The study had been designed to investigate an associa­tion between ABT and the risk of postoperative infection, but instead of conclusively showing increased infection, the investigators observed an increase in mortality. This evi­dence linking ABTs to increased postoperative infections and mortality led to the creation of several larger RCTs, which then showed mixed evidence.
Mechanism
The current understanding is that ABTs create both immuno­modulatory and pro-inammatory effects predominantly through the following mechanisms: [20] (1) infusion of allo­geneic mononuclear cells; (2) soluble biologic response modiers released in a time-dependent manner from WBC granules or membranes into the supernatant uid of RBC or platelet concentrates during storage; and/or (3) soluble human leukocyte antigen (HLA) class I peptides that circu­late in allogeneic plasma.
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Multiple studies support the mechanism that allogeneic WBCs bearing class II HLA antigens are directly involved in immunosuppressing hosts receiving ABTs. The initial stud­ies in the 1970s surrounding renal transplants found that patients who had pre-transplant, WBC-reduced blood trans­fusions showed less immunological benet. This led to fur­ther animal studies by Kao [21] and Bordin [22] that demonstrated immune suppression in recipient mice receiv­ing allogeneic WBCs. Other animal studies [23, 24] looked at the tumor growth-promoting effects of ABTs and noticed that naive animals infused with cells from a donor (given an ABT), or directly given an ABT, had higher rates of pulmo­nary nodules. When the donor animal’s cells or blood were WBC reduced, malignancy rates were restored back to nor­mal in the naive host animals. There was actually a dose­response relationship between the volume of ABT and the number of pulmonary tumor nodules. Because the negative effect of blood transfusion could be eliminated with leukore­duction, it was fair to implicate WBCs (or their products) as causing the noted immunomodulatory effects. In addition to increased pulmonary nodules, these animal studies also hinted at a proliferation of transforming growth factor (TGF)-β-positive suppressor T-cells. Reed etal. [25] discov­ered that donor CD200 molecules (specically on dendritic antigen-presenting cells [APCs]) interact with host γδ- suppressor T-cells, thereby releasing TGF-β and suppressing host immune defenses.
These revelations led to further studies by Beko [26] and Dizik [27] that looked at HLA compatibility between donors and recipients. They concluded that the long-term persistence of a small amount of allogeneic donor WBCs, including dendritic APCs, in the recipient (microchimerism) may account for the downregulation of the recipient’s immune system. In addition to TGF-β, as mentioned above, micro­chimerism may also result in the release of interleukin-4 and interleukin-10 from T-helper type 2 (Th-2) lymphocytes [28]. These cytokines inhibit T-helper type 1 (Th-1) cells, and impairment of Th-1 cytokine secretion results in impair­ment of various functions of cellular immunity (including antigen processing, macrophage activation, the T-cell cyto­toxic function, and neutrophil and monocyte cytocidal activ­ity) [29].
A retrospective study by Utter [30] evaluated 163 American combat veterans who received transfusion in the­ater of operation. He found that 10% of veterans (as much as 20% in Korean War veterans) had evidence of transfusion­associated microchimerism (TA-MC) that, in some instances, lasted upward of 60 years. This was in comparison to the control group who did not receive transfusion and showed a TA-MC rate of 0.7%. Further work by Nelson [31] supported that TA-MC is involved in the pathogenesis of several chronic graft-versus-host-type diseases. More importantly, a more recent study by Reed [32] revealed that TA-MC is present in
approximately one-half of transfusion and severely injured patients at hospital discharge and is not affected by leukore­duction. So, the issue regarding whether leukoreduction is a cure or prevention of TRIM is based on controversial data.
In addition to allogeneic mononuclear cells, a number of bioactive soluble molecules and factors have been shown to detach from these WBCs during storage and have also been implicated in the pathogenesis of TRIM.Nielsen etal. [33] reported that the concentration of histamine, eosinophil cat­ionic protein and protein X, myeloperoxidase, and plasmino­gen activator inhibitor-1 can increase up to 3- to-25-fold in the supernatant uid of RBC components during storage. These cytokines/protein messengers are known to inhibit neutrophil function. Other authors [34, 35] also discovered HLA class 1 antigen and Fas ligand to be among these bioac­tive soluble molecules released during storage– and both of these have been shown to inhibit the natural killer and cyto­toxic T-cells of the recipient, which impairs the destruction of virus-infected cells. The supernatant of stored RBCs with and without leukoreduction is immunosuppressive.
Lastly, it has also been suggested that soluble HLA pro­teins and immune-reactive HLA peptides are involved in the effects of TRIM. Non-polymorphic peptides derived from HLA class I molecules induce antigen-nonspecic immuno­suppression, while polymorphic HLA class I peptides have antigen-specic immunomodulatory effects [36]. During transfusion, allogeneic plasma introduces soluble HLA anti­gens to the recipient’s thymic circulation. According to Roelen [37], a partial or fully matched HLA-DR (HLA with the DR isotope) between host and recipient will lead to toler­ance and immunosuppression, whereas a fully mismatched HLA-DR will lead to alloimmunization. The mechanism also relies on the viability of donor dendritic APCs (present­ing HLA antigens) along with co-stimulatory signals. Non­viable dendritic APCs and a lack of co-stimulatory signals (presumed to be provoked by long refrigerated blood storage times), despite HLA compatibility, can result in T-cell inacti­vation and anergy [33]. Experiments in laboratory animals have shown that when two antigens are introduced, the host’s response to one antigen is almost always decreased. In humans, a wide variety of different antigens are introduced during ABT, and a similar decreased host response as seen in mice could be occurring.
Despite the numerous postulated mechanisms above, it is worth mentioning that Bruson etal. [38] have conclusively shown that ABTs denitely lead to impaired natural killer cell function, alteration in T lymphocyte ratios, defective antigen presentation, suppression of lymphocyte blastogen­esis, decreased macrophage phagocytic function, and inhib­ited neutrophil function [38].
Microparticles of the cell membrane are budded and lost from intact erythrocytes during storage. These microparti­cles are composed of phosphatidyl serine along with certain
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proteins. CD-40L is expressed on the surface of platelets as well as, to a lesser degree, erythrocytes. CD-40L is immuno­suppressive in itself and has been implicated as a protein that sets up the pulmonary vasculature to react, leak, and develop TRALI. CD-40L increases in concentration in the plasma the longer blood is stored, as are the microparticles of budded cell membranes. Macrophages phagocytize these particles, which makes a great deal of sense in that macrophages are programmed to recognize dead or dying cells, clear the cir­culation of these, and recognize cell membranes as potential invaders. When macrophages are exposed to a great deal of these lipids, they become lipid laden, swollen, and dysfunc­tional as they are “full” and satiated from ingesting particles. The longer blood is stored, the larger the number of mic­roparticles that get infused. Inammation and oxidative stress can further worsen these immunomodulatory effects, as oxidated lipids are particularly inammatory. We do not know whether oxidized phosphatidyl serine versus non-oxi­dized is more or less inammatory/immunosuppressive. Some of the latest thinking on preserving RBCs during blood banking involves efforts to make the stored RBCs anoxic thereby decreasing oxidative stress. By reducing oxygen free radical generation, the budding of microparticles is reduced. That technology is not yet in use, but it makes an interesting future research question to examine. We have previously been working on ways to increase oxygen delivery to stored blood during blood banking…which might well be exactly the wrong thing to do (Table31.1).
Postoperative Infection Rates
As mentioned above, the concept of TRIM, although initially embraced as a therapeutic advantage for renal transplanta­tion in the 1970s and 80s, never drew questioning by the
Table 31.1 Postulated mechanisms of the transfusion-related immu-
nomodulation effect [20]
Clonal deletion of specic lines of immune cells Induction of suppressor T-cells Production of anti-idiotypic antibodies Suppression of natural killer cell activity Polarization of the immune system to the T-helper type 2 responses, with suppression of T-helper type 1 responses Selection of non-responder-type immune cells Mixed microchimerism Induction of apoptosis, resulting in the death of specic types of immune-competent cells Accumulation in the supernatant of stored components of soluble molecules (e.g., histamine, eosinophil cationic protein, eosinophil protein X) that inhibit neutrophil function Accumulation in the supernatant of stored components of soluble molecules (i.e., soluble Fas ligand or soluble human leukocyte antigen class I molecules) that inhibit the immune response Others
medical care community as to why or when we should trans­fuse patients. A “belief” persisted, with a particular paternal­ism, that (1) blood transfusion was good and that the risks were minimal and (2) “your doctor knows what is best for you!” Such paternalism continued even in the face of huge numbers of people infected and dying of hepatitis C due to transfusion.
Even today, with a very large supportive literature, the issue of TRIM is still debated. Skeptics of TRIM have put dismissive comments in the literature [
39]. Some of this rep-
resents doubts about a controversial subject wherein propo­nents of TRIM are seen to represent a threat to mainstream beliefs about the “goodness” of transfusion and the standard of practice (10g/dL as a transfusion trigger). However, early proponents of TRIM like Tartter and Blumberg may have also been victims of bad timing. Their work came during and just after the catastrophic transfusion-transmitted AIDS epi­demic of 1981–1987. Few clinicians and investigators in transfusion medicine had any enthusiasm for adding further layers of potential negativity to the already catastrophic news headlines regarding HIV contamination of the blood supply. New data demonstrating that transfusion was even more dan­gerous to patients than originally believed in the early 1980s might represent a “piling on” and a further attack upon the much-revered medical teaching.
With some animal studies suggesting that TRIM is medi­ated by donor allogeneic WBCs that either directly down­regulate the recipient’s immune function or indirectly mediate the alleged TRIM effects by releasing soluble medi­ators into the supernatant uid of RBCs during storage, nine RCTs were conducted to determine if leukoreduction of blood led to lower postoperative infection rates.
Six of the nine studies showed lower postoperative infec­tion rates with leukoreduction, and the other three did not: the three not showing a reduction in TRIM by leukoreduc­tion have been criticized for their design, whereas the others were simply accepted as fact. Perhaps the paternalism and belief system of transfusion again overcame science.
The study by van der Watering etal. [
19] randomized 871
eligible patients with colorectal cancer receiving blood to get leukocyte-depleted RBCs or packed cells without a buffy coat. They reported “no statistically signicant differences” in overall infection or cancer rates between the two groups. A potential aw in this study is that buffy coat-depleted cells are inherently leukoreduced. Therefore, when the control arm of an RCT consists of already-leukoreduced blood, especially considering it was buffy coat-depleted and not just buffy coat-reduced (leading to greater leukoreduction), one would expect little if any difference in immunosuppression between the control and treatment arms.
Wallis randomized 597 patients undergoing elective coro­nary artery or heart valve surgery to receive either plasma­reduced, buffy coat-depleted, or WBC-ltered RBC [40].
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The authors concluded that there was no difference in infec­tion rates between the three arms after they excluded uri- nary tract infections (UTIs), which were signicantly elevated in the plasma-reduced arm [40]. UTIs are most de­nitely a signicant nosocomial infection of major importance to postoperative adverse outcomes, length of hospital stay, and even mortality. When including UTIs and comparing all postoperative infections among the three arms (plasma­reduced 33%, buffy coat-depleted 19%, WBC-ltered 22%; P=0.03 adjusted for other variables), there is at least an 11% increase in infections between fully (WBC-ltered) and par­tially (buffy coat-depleted) leukoreduced cells. Additionally, the authors claimed to have higher infection rates in the WBC-ltered arm at the 3-month follow-up [40]. However, the majority of these were self-reported infections that were proven by bacterial culture, radiologic ndings, or docu­mented fever while the study participant was as inpatient. Self-reporting of infection is a notoriously ineffective and unscientic way to follow this potentially devastating outcome.
Titlestad randomized 112 patients to receive leukocyte­depleted erythrocyte suspensions or non-leukocyte-depleted erythrocyte suspensions to patients undergoing colorectal surgery [41]. Despite claiming that “no signicant difference between the transfusion groups was seen on any single infec­tious event,” the infection rate in the leukoreduced arm was still 7% lower (38% vs. 45%; P=0.52). Additionally, with a P-value as a high as 0.52 and small patient population (com­pared to the other studies exceeding 500+ patients), the validity of the result is questionable [41].
A meta-analysis of the nine studies by Neil Blumberg [42], limiting patients who actually received transfusions (n=3093) and applying the intention to treat principle, dem­onstrated that leukoreduced transfusions signicantly reduced the odds of postoperative infection (odds ratio = 0.522; 95% CI, 0.332–0.821; P = 0.005). Another meta-analysis by Fergusson etal. [43], including only trans­fused patients as well, found a statistically and clinically sig­nicant reduction in postoperative infection following leukoreduction (relative risk [RR] = 0.60; 95% CI, 0.38–
0.93). Today, therefore, it is generally accepted that leukore­duction itself decreases the effects of TRIM, yet it still exists and is a problem [44].
A meta-analysis by Vamvakas etal. [39] reached contrary conclusions. However, their meta-analysis included hun­dreds of non-transfused patients that were intentionally excluded from the original RCTs, as well as from two meta­analyses that showed higher postoperative infections. Non­transfused patients are not relevant when it comes to the question of whether transfusion-related immunomodulation has clinically signicant effects or whether leukoreduction can reduce such effects [42]. The reasoning for this isthat one must compare leukoreduced versus non- leukoreduced
blood transfusions to determine the true effect of immuno­modulation. The use of the intention-to-treat analysis (com­pared to the as-treated analysis) in this instance included patients that did not receive transfusions, accounting for more than 10% of the analyzed patients in most cases,there­fore diluting any potential benecial effect of leukoreduction.
For rigorous statistical analyses, inclusion of any patient that was randomized is usually critical. However, exclusion of these patients provides a more scientically valid exami­nation of the outcomes between patients who received non­leukoreduced or leukoreduced transfusions, excluding patients who received no transfusions at all. Fergusson [43] has argued this point successfully and shown that trial inves­tigators can exclude patients’ data from analysis, without risking bias, when ineligible patients are mistakenly random­ized into a trial.
Most problematically, this study does not in all instances correspond to the actual data from the original studies. Rather, for some of the clinical trials, the meta-analyses included “imputed” outcomes. This effort was an attempt to retrospectively create an “intention-to-treat analysis.” The authors took non-transfused patients from several studies and the number of postoperative infections and divided them in half. They then added these non-transfused patients and infections back to the actual published data from the trans­fused patients. However, as mentioned, data from non­transfused patients, and certainly data not derived from experimental results, have little to no scientic validity in assessing either transfusion immunomodulation or the effects of leukoreduction [42].
The British Isles have essentially done a large human experiment. They intentionally went to universal leukore­duction which was a misdirected attempt to avoid the trans­fusion of prions (potential mad cow disease) among their population. The thinking at the time was that the vector for “mad cow” disease must be neutrophil transmitted, and thus by universal leukoreduction, they would eliminate/reduce that potential catastrophic aspect for blood transfusion. We now know that prions are carried in the plasma and have nothing to do with leukocytes. The incidence of periopera­tive infection did not change across Britain from before leu­koreduction to after it was established, and those patients not transfused do far better. Even with that data, the “belief” that leukoreduction reduces TRIM persists. Perhaps we really do not have a scientic answer– only “beliefs” and desires to nd things better persist with regard to transfusion.
Most recently, a meta-analysis by Kwon [45] in 2016 investigated the impact of allogeneic versus autologous leukocyte- ltered blood transfusions on the incidence of postoperative infections in adult surgical patients. They eval­uated 16 randomized controlled trials involving 6586 ran­domized (ITT) patients (4615 APP patients) in various
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clinical settings. The results demonstrated an overall 26% risk reduction among the leukocyte-ltered blood group in postoperative infections when analyzed by APP (RR=0.74; 95% CI, 0.60–0.92; P = 0.007) and a 22% risk reduction when analyzed by ITT (RR = 0.78; 95% CI, 0.65–0.94; P = 0.009). Leukocyte-ltered blood was also associated with a signicant reduction in length of stay (standardized difference of mean = −0.74; 95% CI, −1.32 to −0.15; P = 0.014) and all-cause mortality (RR = 0.74; 95% CI,
0.57–0.95; P = 0.018) [45]. We can safely conclude that leukocyte- ltered (reduced) blood transfusions are associ­ated with signicantly lower postoperative infection rates in both the APP and ITT populations. This lends support to the argument that non-leukocyte-reduced whole blood has dele­terious immunosuppressive effects.
Additionally, an argument made by many of the skeptics that doubted or underestimated the effects TRIM over the past two decades was that transfusion is a surrogate marker for the severity of the patient’s condition or other confound­ing factors. And while it is true that confounded associations can sometimes lead to adverse outcomes, sometimes even at high as a 100%, outcomes beyond the point begin to point toward cause and effect. According to A.B.Hill’s “rules of causality” (the basis of evidence-based medicine), a posi­tively strong dose-response relationship is a good indicator for causality and not simply correlation. Therefore, an increasing dose of blood should in theory lead to a larger response of immunosuppression and/or postoperative infec­tion. Blumberg etal. eloquently expounded on this theory in a 2007 TRANSFUSION publication in which he drew paral­lels with smoking and lung cancer in which a cause and effect is taken as proven [45]. The risk of lung cancer in patients that smoke is so far above what confounders could cause, that without RCT’s medicine has assigned it causality. Similarly, the rate of perioperative immunosuppression is so high, up to sevenfold increased, after transfusion that con­founders cannot be responsible [45].
Furthermore, transfusion practices vary almost an order of magnitude in the clinical setting, from patient to patient, physician to physician, and hospital to hospital. The conten­tion that transfusion could act as a precise and reliable indi­cator of clinical tumor staging or severity of illness is, in retrospect, implausible.
Conclusion
In 2010, President Bill Clinton made the statement that unnecessary RBC transfusion was the third largest killer by human error of Americans. He may well have been correct, and the problem now is how to dene a “necessary transfu­sion.” Clearly, we do not have an answer to that, but the data on TRIM should be sobering to the medical care community.
Perioperative infection prolongs hospital stay and is linked to any number of other adverse outcomes, and a great deal of money is spent on giving prophylactic antibiotics as well as the appropriate timing of these antibiotics before surgery. The risks of TRIM and the outcome data are of the same magnitude of effect when one looks at transfusion and peri­operative infection as that seen with proper use of antibiot­ics. Yet few physicians, hospital administrators, or regulators see the connection or are willing to expend the same resources to educate medical personnel on patient blood management or reducing unnecessary transfusion. Few if any hospital epidemiologists know of the effect of transfu­sion and TRIM on infection in their hospital. There still appears to exist the same bias and teaching that blood trans­fusion is good. Those places that have implemented compre­hensive blood management programs have seen reductions in perioperative infection rates. Perhaps persons of inuence in The Joint Commission and the Centers for Medicare & Medicaid Services should examine President Clinton’s words and reect on how we should change our practice to understand the importance of TRIM.
Future research need not spend time and effort proving that TRIM exists. It does. What needs to be researched are more methods to reduce RBC storage defects and efforts to educate the medical community regarding proper/best prac­tices in transfusion medicine. Patient blood management is leading efforts to use focused methods to reduce anemia and salvage the patient’s own blood, and with these interven­tions, perhaps nosocomial infection and cancer recurrence can be reduced.
Conict of Interest None.
References
1. Ellingson KD, Sapiano MRP, Haass KA, et al. Continued decline
of blood collection and transfusion in the United States-2015. Transfusion. 2017;57:1588–98.
2. Edens C, Haass KA, Cumming M, etal. Evaluation of the National
Healthcare Safety Network Hemovigilance Module for transfusion­related adverse reactions in the United States. Transfusion. 2019;59:524–33.
3. Block TM, Alter HJ, London WT, Bray M.A historical prospective
on the discovery and elucidation of the hepatitis B virus. Antivir Res. 2016;131:109–23.
4. Stramer SL.Current perspectives in transfusion-transmitted infec-
tious diseases: emerging and re-emerging infections. ISBT Sci Ser. 2014;9:30–6.
5. Perrotta PL, Snyder EL.Non- infectious complications of transfu-
sion therapy. Blood Rev. 2001;15:69–83.
6. Hendrickson JE, Hillyer CD. Noninfectious serious hazards of
transfusion. Anesth Analg. 2009;108:759–69.
7. Gilliss BM, Looney MR, Gropper MA.Reducing non-infectious
risks of blood transfusion. Anesthesiology. 2011;115:635–49.
8. Harvey AR, Basavaraju S, Chung KW, Kuehnert M.Transfusion-
related adverse reactions reported to the National Healthcare
31 Transfusion Related-Immunomodulation in Relation to Perioperative Infection/Cancer: Biology, Evidence, and Controversy…
https://t.me/medicina_free
327
Safety network Hemovigilance Module, United States 2010–2012. Transfusion. 2015;55:709–18.
9. Manoukian S, Stewart S, Dancer S, etal. Estimating excess length of stay due to healthcare-associated infections: a systemic review and meta-analysis of statistical methodology- Review. J Hosp Acquir Infect. 2018;100:222–35.
10. Opelz G, Sengar DP, Mickey MR, Terasaki PI. Effect of blood transfusions on subsequent kidney transplants. Transplant Proc. 1973;5:253–9.
11. Morris PJ, Ting A, Stocker J.Leukocyte antigens in renal transplan­tation. 1. The paradox of blood transfusions in renal transplanta­tion. Med J Aust. 1968;24:1088–90.
12. Fabre JW, Morris PJ. The mechanism of specic immunosup­pression of renal allograft rejection by donor strain blood. Transplantation. 1972;14:634–40.
13. Thoenes GH, Pielsticker K, Schreiber MA. Blood transfusion­induced facilitation of kidney graft survival in rats (congenic­resistant strains). Clin Nephrol. 1980;13:133–41.
14. Keowan PA, Descamps B.Improved renal allograft survival after blood transfusion: a non-specic, erythrocyte-mediated immuno­regulatory process? Lancet. 1979;8106:20–2.
15. Gatenby PA, Cameron K, Simes RJ, Adelstein S, Bennett MJ, Jansen RP, Shearman RP, Stewart GJ, Whittle M, Doran TJ.Treatment of recurrent spontaneous abortion by immunization with paternal lymphocytes: results of a controlled trial. Am J Reprod Immunol. 1993;29:88–94.
16. Gantt CL.Red blood cells for cancer patients. Lancet. 1981;2:363.
17. Murphy P, Heal JM, Blumberg N. Infection or suspected infec­tion after hip replacement surgery with autologous or homologous blood transfusions. Transfusion. 1991;31:212–7.
18. Jensen LS, Kissmeyer-Nielsen P, Wolff B, Qvist N. Randomised comparison of leucocyte-depleted versus buffy-coat-poor blood transfusion and complications after colorectal surgery. Lancet. 1996;348:841–5.
19. van de Watering LMG, Hermans J, Houbiers JGA, van den Broek PJ, Bouter H, Boer F, Harvey MS, Huysmans HA, Brand A.Benecial effect of leukocyte depletion of transfused blood on post-operative complications in patients undergoing cardiac sur­gery: a randomized clinical trial. Circulation. 1998;97:562–8.
20. Vamvakas EC, Blajchman MA.Transfusion-related immunomodu­lation (TRIM): an update. Blood Rev. 2007;21:327–48.
21. Kao KJ. Induction of humoral immune tolerance to major histo­compatibility complex antigens by transfusions of UV-B irradiated leukocytes. Blood. 1996;88:4375–82.
22. Bordin JO, Heddle NM, Blajchman MA. Biologic effects of leu­kocytes present in transfused cellular blood products. Blood. 1994;84:1705–21.
23. Blajchman MA, Bardossy I, Carmen R, Sastry A, Singal DP.Allogeneic blood transfusion-induced enhancement of tumor growth: two animal models showing amelioration by leukodeple­tion and passive transfer using spleen cells. Blood. 1993;81:1880–2.
24. Clark DA, Gorczynski RM, Blajchman MA. Transfusion-related immunomodulation due to peripheral blood dendritic cells express­ing the CD200 tolerance signaling molecule and alloantigen. Transfusion. 2008;48:814–21.
25. Reed SG. TGF-β in infections and infectious disease. Microbes Infect. 1999;1:1313–25.
26. Beko KR, Tran HO, Hewitt CW, Black KS, Patel MP, Ramsamooj R, Martin DC.Mechanisms of prior blood transfusion- cyclosporine­induced tolerance: a potential role for immune-cellular chimerism. Transplant Proc. 1991;23:147–8.
27. Dzik WH.Mononuclear cell microchimerism and the immunomod­ulatory effect of transfusion. Transfusion. 1994;34:1007–12.
28. Kirkley SA, Cowles J, LPelligrini Jr VD, Harris CM, Boyd AD, Blumberg N.Blood transfusion and total joint replacement surgery: T-helper 2 cytokine secretion and clinical outcome. Transf Med. 1998;8:195–204.
29. Gafter U, Kalechman Y, Sredni B. Blood transfusion enhances production of T-helper-2 cytokines and transforming growth factor beta in humans. Clin Sci (Lond). 1996;91:519–23.
30. Utter GH, Lee TH, Rivers RM, Montalvo L, Wen L, Chafets DM, Reed WF, Busch MP. Microchimerism decades after transfusion among combat-injured US veterans from the Vietnam, Korean, and World War II conicts. Transfusion. 2008;48:1609–15.
31. Nelson JL.HLA relationships of pregnancy, microchimerism and autoimmune disease. J Reprod Immunol. 2001;52:77–84.
32. Reed W, Lee TH, Norris PJ, Utter GH, Busch MP.Transfusion­associated microchimerism: a new complication of blood transfu­sions in severely ill patients. Semin Hematol. 2007;44:24–31.
33. Nielsen HJ, Reimert CM, Pedersen AN, Brünner N, Edvardsen L, Dybkjaer E, Kehlet H, Skov PS.Time-dependent, spontaneous release of white cell- and platelet-derived bioactive substances from stored human blood. Transfusion. 1996;36:960–5.
34. Ghio M, Contini P, Mazzei C, Brenci S, Barberis G, Filaci G, Indiveri F, Puppo F.Soluble HLA class I, HLA class II, and Fas ligand in blood components: a possible key to explain the immu­nomodulatory effects of allogeneic blood transfusion. Blood. 1999;93:1770–7.
35. Puppo F, Contini P, Ghio M, Brenci S, Scudeletti M, Filaci G, Ferrone S, Indiveri F.Soluble human MHC class I molecules induce soluble Fas-ligand secretion and trigger apoptosis in activated CD8+ Fas (CD95)+ T lymphocytes. Int Immunol. 2000;12:195–203.
36. Magee CC, Sayegh MH. Peptide-mediated immunosuppression. Curr Opin Immunol. 1997;9:669–75.
37. Roelen DL, van Rood JJ, Brand A, Claas FH.Immunomodulation by blood transfusions. Vox Sang. 2000;78:273–5.
38. Brunson ME, Alexander JW. Mechanisms of transfusion-induced immunosuppression. Transfusion. 1990;30:651–8.
39. Vamvakas EC, Blajchman MA. Deleterious clinical effects of transfusion- associated immunomodulation: fact or ction? [review]. Blood. 2001;97:1180–95.
40. Wallis JP, Chapman CE, Orr KE, Clark SC, Forty JR. Effect of WBC reduction of transfused RBCs on postoperative infection rates in cardiac surgery. Transfusion. 2002;42:1127–34.
41. Titlestad IL, Ebbesen LS, Ainsworth AP, Lillevang ST, Qvist N, Georgsen J. Leukocyte-depletion of blood components does not signicantly reduce the risk of infectious complications. Results of a double-blinded, randomized study. Int J Color Dis. 2001;16:147–53.
42. Blumberg N. Deleterious clinical effects of transfusion immu­nomodulation: proven beyond a reasonable doubt. Transfusion. 2005;45:33S–9; discussion 39S–40.
43. Fergusson D, Aaron SD, Guyatt G, Hebert P.Post-randomization exclusions: the intention to treat principle and excluding patients from analysis. BMJ. 2002;325:652–4.
44. Blumberg N, Zhao H, Wang H, Messing S, Heal JM, Lyman GH.The intention to treat principle in clinic trials and meta-analysis of leukoreduced blood transfusion in surgical patients. Transfusion. 2007;47:573–81.
45. Kwon S, Lew S, Chamberlain RS.Leukocyte ltration and postop­erative infections. J Surg Res. 2016;205:499–509.
Origins ofBlood Products
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ElyseM.Cornett, MatthewB.Novitch, CodyKoress, MitchellC.Fuller, SamuelCarlson, JenniferKaiser, NataliaOkon, andAlanDavidKaye
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Introduction
The rst recorded transfusion occurred in 1628 by British physician William Harvey who also discovered the circula­tion of blood [1]. The rst successful transfusionoccurred in 1665 and involved transferring blood from one dog to another dog, and in 1667 blood was successfully transferred from sheep to humans. In 1900, Karl Landsteiner discov­ered blood groups A, B, andO when he mixed the red cells and serum of each of his staff, ultimately revealing why some blood transfusions are deadly [2]. The ABO blood typ­ing system is still relevant today in transfusion and transplantation.
Technological development facilitated the elaboration of the cardiovascular system, which is fundamentally dened by the transportation of blood to tissue. Blood is a living tis­sue composed of three types of blood cells: red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes). This cellular component comprises 40% of the total blood volume [3]. The function of red blood cells (RBC) is to transport oxygen to peripheral tissues and carry carbon dioxide away from tissues. The function of white blood cells (WBC) is to defend the body against infectious
disease and foreign materials by orchestrating the human immune response. Thrombocyte’s assist in blood clotting and coagulation homeostasis [4]. Plasma comprises 60% of blood by volume and functions as the liquid component of blood, which carriesthe cellular components (RBC, WBC, and platelets) to peripheral tissues [5].
Blood transfusion has been used by clinicians since the twentieth century to treat pathophysiologic conditions such as anemia and hemorrhage. Transfusion of blood products, (which are collected, tested, prepared, stored, and trans­ported in concordance with FDA regulations from a donor to a patient), are needed to sustain life or improve conditions. While whole blood can provide improved oxygen-carrying capacity, volume expansion, and replacement of clotting fac­tors, specic component therapy is equally effective and a more efcient use of donated blood [6]. Packed red blood cells (RBCs), washed RBCs, WBC-depleted RBCs, fresh frozen plasma (FFP), cryoprecipitate, platelets, and white blood cells are commerciallymade and can alsobe processed from bone marrow [7].
There are guidelines to ensure the safety of blood transfu­sions and toensure thatblood products are safe. Effortsto ensure safety include increased staff trainings on the blood
E. M. Cornett LSU Health Shreveport, Department of Anesthesiology, Shreveport, LA, USA e-mail: ecorne@lsuhsc.edu
M. B. Novitch ( University of Washington Medical Center, Department of Anesthesiology, Seattle, WA, USA e-mail: mnovitch@uw.edu
C. Koress LSU Health Sciences Center, Department of Anesthesiology, New Orleans, LA, USA e-mail: ckores@lsuhsc.edu
M. C. Fuller Froedtert Hospital, Medical College of Wisconsin, Milwaukee, WI, USA e-mail: mfuller@mcw.edu
© Springer Nature Switzerland AG 2021 C. S. Scher et al. (eds.), Essentials of Blood Product Management in Anesthesia Practice,
https://doi.org/10.1007/978-3-030-59295-0_32
*)
S. Carlson · J. Kaiser Medical College of Wisconsin, Department of Anesthesiology, Wauwatosa, WI, USA e-mail: Sacarlson@mcw.edu; jkaiser@mcw.edu
N. Okon Department of Anesthesiology, Wauwatosa, WI, USA
nokon@mcw.edu
e-mail:
A. D. Kaye Department of Anesthesiology and Pharmacology, Toxicology, and Neurosciences, Louisiana State University School of Medicine-Shreveport, Shreveport, LA, USA
LSU Health Shreveport School of Medicine, New Orleans, LA, USA
Tulane School of Medicine, New Orleans, LA, USA e-mail: akaye@lsuhsc.edu
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