Blood utilization in liver transplantation (BUILT): A multidisciplinary survey of transfusion practices.

BACKGROUND: The purpose of this study was to survey liver transplant centers in the United States to assess baseline practices in blood utilization and identify opportunities for standardization to optimize blood use in these complex cases. STUDY DESIGN AND METHODS: Two surveys, one for transfusion medicine physicians and the other for anesthesiologists, were distributed to high-volume liver transplant centers. RESULTS: The response rate was 52% for both surveys. The majority of respondents (90%) indicated they issue a standardized number of blood products to start surgeries. The most common number of products issued before the start of cases were 10 red blood cells (RBC) and 10 plasma units with no platelets or cryoprecipitate. On average, fewer RBC (7.5) and plasma (7) units were transfused than issued. Decisions to transfuse RhD+ RBCs to RhD- patients and use antigen untested units in alloimmunized patients were mainly handled on a case-by-case basis. Many centers reported utilizing viscoelastic testing (97%) and cell salvage (97%). Most centers reported standardized, laboratory-based intraoperative transfusion goals for RBCs (65%) and fibrinogen replacement (52%) but lacked a standardized approach for plasma (55%) and platelets (58%). DISCUSSION: More blood products are issued during surgery than are transfused. Responses from anesthesiology providers suggest a broad consensus on practice. Almost all respondents use viscoelastic testing in the management of intraoperative coagulopathy, either alone or in combination with classical coagulation tests. The majority of programs do not transfuse clotting factor concentrates, including fibrinogen concentrate, prothrombin complex concentrates, and recombinant activated FVII, and do not use antifibrinolytics prophylactically.

Survey of blood collection and transfusion practices among institutions in Africa.

INTRODUCTION: Dramatic improvements in blood transfusion have occurred during the last two decades. Transfusion medicine services and practices in Africa remain underexplored. METHODS: A survey of blood bank/transfusion medicine (BBTM) practices, available blood products, blood product source(s), pre-transfusion testing, and blood donor infectious disease testing methodologies across Africa was performed using the American Society for Clinical Pathology (ASCP) listserv. Survey recipients included hospital-based laboratories/blood banks, national transfusion medicine services, and free-standing laboratories (collectively referred to as institutions). RESULTS: Responses from a total of 81 institutions across 22 countries were analyzed. All 81 institutions provide at least one type of blood product-whole blood, red blood cells (RBCs), platelets, plasma, and cryoprecipitate, with whole blood (90.1%, 73 of 81) and RBCs (79.0%, 64 of 81) most common, while cryoprecipitate is least common (12.4%, 10 of 81). Only five countries had a responding institution that provides all types of products. Among institutions that collect blood onsite, the most common sources of blood products are patients' family members (94.1%, 48 of 51) and pre-screened on-demand volunteer donors (82.4%, 42 of 51). The most commonly screened infectious agents are HIV and hepatitis B virus (both 81.5%), while 70.4% (57 of 81) test for hepatitis C virus (HCV) and Treponema pallidum. DISCUSSION: This study highlights significant variability and restrictions in blood product availability, pre-transfusion testing, and blood donor infectious disease testing across Africa. Further studies are needed to ascertain barriers to improving blood donor availability, blood product safety, and infectious disease testing.

How do I manage a blood product shortage?

BACKGROUND: The demand for blood products sometimes exceeds the available inventory. Blood product inventories are dependent upon the availability of donors, supplies and reagents, and collection staff. During prolonged extreme shortages, blood centers and transfusion services must alter practices to meet the needs of patients. STUDY DESIGN AND METHODS: The Association for the Advancement of Blood and Biotherapies Donor and Blood Component Management Subsection compiled some strategies from its blood center and hospital transfusion service members that could be implemented during blood product shortages. RESULTS: Some strategies that blood centers could use to increase their available inventories include increasing donor recruitment efforts, using alternate types of collection kits, manufacturing low-yield apheresis-derived platelets and/or whole blood-derived platelets, using cold-stored platelets, transferring inventory internally among centers of the same enterprise, using frozen inventory, decreasing standing order quantities, prioritizing allocation to certain patient populations, filling partial orders, and educating customers and blood center staff. Transfusion service strategies that could be implemented to maximize the use of the limited available inventory include increasing patient blood management efforts, using split units, finding alternate blood suppliers, trading blood products with other hospital transfusion services, developing a patient priority list, assembling a hospital committee to decide on triaging priorities, using expired products in extreme situations, and accepting nonconforming products after performing safety checks. DISCUSSION: Blood centers and transfusion services must choose the appropriate strategies to implement based on their needs.

Transfusion medicine research in Africa: Insights from investigators in the field.

BACKGROUND AND OBJECTIVES: Research in low-resource settings is inherently challenging. We sought to assess the factors that have impeded or facilitated transfusion medicine (TM) research in various African settings. MATERIALS AND METHODS: A qualitative case study was conducted of selected investigators in Africa; selection was based on productivity-spanning publication, leadership and research in TM. We designed a questionnaire to explore the factors impeding or facilitating TM research to understand the impact on the investigators' careers. Written responses were independently coded and double-checked for precision. Qualitative analysis was conducted, whereby responses were grouped thematically and clustered by relationship. The initial findings were discussed with respondents to validate and refine the interpretations. The recorded transcript was analysed and incorporated into the final analysis. RESULTS: Six investigators participated in the study. Their responses yielded 471 coded comments: 389 from the questionnaires and 82 from the ensuing discussion. The most frequently cited factors described included knowledge and intellectual abilities (n = 104), personal effectiveness (n = 99), research and governance structure (n = 97), and engagement, influence and impact (n = 75). Four relationship clusters emerged from the facilitators (n = 42), barriers (n = 28), and common approaches (n = 26) to research, informing summary themes of adaptation, collaboration, perseverance, and resiliency. CONCLUSION: Individual attributes were found to be central to a successful TM research career in African settings. However, given other public health priorities and constraints, interpersonal relationships, organizational structures and the broader research context were important to TM researchers. Overcoming complexities demands adaptation, collaboration, perseverance and resiliency.

A multidisciplinary comparison of transfusion and perioperative support for high-risk cardiac surgery at three large academic centres in North America.

Cardiac surgery is associated with numerous peri- and post-operative haemostatic complications and blood transfusion requirements. Complex procedures such as redo-sternotomy heart transplantation or type A aortic dissection repairs are at high-risk for severe coagulopathy and significant transfusion requirements. However, current practice guidelines do not specifically address high-risk surgeries, resulting in variable practice. To optimise outcomes, a multidisciplinary approach to blood transfusion and haemostasis is critical. How individual institutions construct these multidisciplinary teams, delegate responsibilities, and build procedures may differ depending on the institution and availability of resources. In this article, we compare how the transfusion medicine services support their cardiac surgery and transplant programs at three large medical centres-Vanderbilt University Medical Center (the largest heart transplant centre in the world by volume in 2021), Toronto General Hospital-University Health Network (a quaternary-care centre in Canada's most populous city, performing more >20 heart transplants annually), and Vancouver General Hospital (a quaternary-care centre that performs numerous high-risk cardiac surgeries). This article discusses management from multiple perspectives, including the blood bank and perioperative environments, and highlights how institutions have evolved their programs in accordance with nation-specific policies and provisions.

Empathy across cultures - one size does not fit all: from the ego-logical to the eco-logical of relational empathy.

Empathy is extolled in Western healthcare and medical education as an exemplary quality to cultivate in trainees and providers. Yet it remains an elusive and inadequately understood attribute. It posits a "one size fits all" unidimensional attribute applicable across contexts with scant attention given to its multifaceted dimensions in intercultural contexts. In this article, we uncloak the shortcomings of this conventional empathy in intercultural settings, and instead propound an expanded "relational empathy".

COVID-19 and the impact on blood availability and transfusion practices in low- and middle-income countries.

BACKGROUND/CASE STUDIES: The coronavirus disease 2019 (COVID-19) pandemic disrupted the global blood supply. Low- and middle-income countries (LMICs) already experienced blood supply deficits that preceded the pandemic. We sought to characterize the challenges experienced during the pandemic, and adaptations, such as COVID-19 convalescent plasma (CCP). STUDY DESIGN/METHODS: A cross-sectional survey explored blood availability, challenges, and adaptations. The survey contained 31 questions, e-mailed in English, French, or Spanish, to selected LMIC blood transfusion practitioners. Data acquisition occurred between October 28 and December 28, 2020. A mixed methods analysis followed. RESULTS/FINDINGS: A total of 31 responses from 111 invitations represented 26 LMIC countries. Languages included English (22, 71%), Spanish (7, 22.6%), and French (2, 6.4%). Most respondents (29/31, 93.5%) collected blood; 58% also transfused blood (18/31). The supply of blood came from hospital-based blood donations (61%, 11/18); blood suppliers (17%, 3/18); and both sources (22%, 4/18). Collectively, 77.4% (24/31) of respondents experienced a decline in blood availability, ranging from 10% to 50%. Contributing factors included public fear of COVID-19 (21/24); stay-at-home measures (18/24); logistics (14/24); and canceled blood drives (16/24). Adaptations included increased collaboration within and between institutions (17/27), donor eligibility changes (21/31); social media or phone promotion (22/39); and replacement donation (3/27). Fifteen of 31 responses reported CCP donation (48.4%); CCP transfusion occurred in 6 (19.4%). The primary barrier was engaging recovered patients for donation (7/15). CONCLUSION: Our survey describes challenges experienced by LMIC blood systems during the COVID-19 pandemic. While the decline in blood supplies was severe, adaptive measures included collaboration, outreach, and CCP programs.

A rare case of a clinically significant anti-M alloantibody in a heart transplant recipient.

INTRODUCTION: Anti-M antibodies are usually inactive at physiologic temperatures (37 °C). Rarely, these antibodies have been reported to react at physiologic temperatures, resulting in clinically significant hemolytic transfusion reactions or hemolytic disease of the fetus and newborn. PATIENT AND METHODS: We describe a case of an acute hemolytic transfusion reaction due to an anti-M alloantibody reacting at physiologic temperatures in a critically ill patient. RESULTS: Proper identification and management of anti-M antibody-mediated acute hemolysis rapidly improved and stabilized her hemoglobin. CONCLUSION: Differentiation between anti-M antibody-mediated acute hemolysis and its differential diagnoses is of critical importance to guide therapeutic decisions in these rare clinical scenarios.

COVID-19 associated with severe autoimmune hemolytic anemia.

BACKGROUND: Autoimmune hemolytic anemia (AIHA) has many known disease associations, including autoimmune, lymphoproliferative, and certain infectious diseases, as well as various medications. Studies have found that severe cases of coronavirus disease 2019 (COVID-19) may be associated with coagulopathies; however, the potential association with AIHA is not clear. CASE REPORT: A patient with no known risk factors or underlying predisposition for developing AIHA presented to a hospital with vague symptoms and profound anemia with a complicated blood bank evaluation. She was found to have COVID-19 and AIHA, for which extensive laboratory testing was performed, including direct antiglobulin tests, elution studies, and cold agglutinin titers, to identify the causative autoantibody. She required multiple blood transfusions and therapeutic interventions before clinical stabilization. DISCUSSION: AIHA is a complex disease with a spectrum of presentations and clinical severity. Many diseases have been associated with a propensity for developing AIHA; however, there are few cases in the literature of patients with COVID-19 and AIHA. Most of the reports involve patients with other underlying conditions that are known to be associated with the development of AIHA. The presentation, clinical findings, and therapeutic interventions in a patient with severe AIHA, without other underlying conditions, in the setting of COVID-19 are discussed. CONCLUSIONS: There are few reports of patients with concurrent COVID-19 and AIHA, and the association is not clear. Although COVID-19 has been shown to be associated with coagulopathies, more research is required to determine whether AIHA may also be a potential complication.

Global survey of transfusion medicine curricula in medical schools: Challenges and opportunities.

BACKGROUND: Physician's knowledge in transfusion medicine (TM) is critical for patient safety. Therefore, ensuring that medical schools provide adequate education in TM is important. The aim of this study was to assess the status of TM education at a global level. STUDY DESIGN AND METHODS: A comprehensive anonymous survey to assess TM education in existing medical school curricula was developed. The survey was distributed to deans and educational leads of medical schools in a range of low-, medium-, high-, and very high-human development index (HDI) countries. It included 20 questions designed to assess specific domains including structure of TM curriculum and teaching faculty. RESULTS: The response rate was 53%. The majority of responding schools from very-high-HDI countries offered a 6-year curriculum after high school or a 4-year curriculum after college education, whereas most schools from medium-HDI countries offered a 5-year medical curriculum. A formal teaching program was available in only 42% of these schools in contrast to 94% of medical schools from very high-HDI. Overall, 25% of all medical schools did not offer structured TM teaching. When offered, most TM teaching was mandatory (95%) and integrated within the third and fourth year of medical school. Formal assessment of TM knowledge was done in 72% of all responding medical schools. More than half of the deans considered the TM education in their medical schools as inadequate. CONCLUSION: Despite its limitations, the current survey highlights significant gaps and opportunities of TM education at a global scale.

Transfusion Safety Officers in the United States: Survey of characteristics and approaches to implementation.

BACKGROUND: Transfusion safety officers (TSO) function as liaisons between the blood bank and clinical staff, utilizing audits, quality improvement, reviews, communication, education, and general vigilance to enhance transfusion safety. While hospitals in Europe and Canada have long employed TSOs, a majority of institutions in the United States (US) have yet to implement this resource, despite the mounting evidence to support their effectiveness. STUDY DESIGN AND METHODS: An anonymous 20-question survey was administered to 104 hospitals with valid email contact information. Survey questions addressed the presence of a TSO, characteristics, backgrounds, and education of TSOs, the reporting and funding structure of the position, and role responsibilities. RESULTS: 53 responses were received, with 52 surveys completed (51 % response rate). The majority of responding institutions have a patient blood management (PBM) program (n = 40, 77 %) and 33 (63 %) have at least 1 TSO. 61 % of TSOs report an educational background in nursing, with 11 additional unique training backgrounds identified. TSO responsibilities are varied and include quality improvement, education, transfusion safety event analysis, and participation in PBM initiatives. Barriers to implementing a TSO position include lack of resources, financial impediments, and a lack of understanding of the position and its value by administrators and clinicians. DISCUSSION: The results of this survey highlight how TSOs contribute to transfusion safety and PBM and may provide guidance to hospitals interested in implementing a TSO position. It also elucidates the range of TSO responsibilities and approaches that institutions utilize to advocate for, and implement, this position in the US.

Low rates of anti-recipient isohemagglutinins in ABO incompatible hematopoietic stem cell transplants.

INTRODUCTION: Isohemagglutinins occur naturally and form in an 'opposite' (antigen-negative) pattern to a patient's ABO blood type. Patients undergoing minor and bidirectional ABO incompatible hematopoietic stem cell transplantation (HSCT) may demonstrate detectable antibodies against their native blood type. In this study, we sought to characterize the rates of such antibody formation and evaluate the clinical significance of our findings. MATERIALS AND METHODS: An internal database of HSCT patients at an academic medical center was queried for ABO incompatible transplant patients from 2009-2019. Serum typing results, clinical histories, and laboratory data were compiled and reviewed. RESULTS: A total of 182 minor and bidirectional ABO incompatible HSCT patients were identified. Anti-recipient isohemagglutinins were found in 9% (16/182) of the HSCT patients. The rate was higher in patients with minor incompatibility (12%: 15/127) versus bidirectional ABO incompatibility (2%: 1/55) (p = 0.04). No anti-recipient isohemagglutinins were identified in umbilical cord HSCT patients (0%: 0/7). Serologic agglutination reactions of recipient isohemagglutinins were overall mostly weak (13/16 weak + to 1+). There was a trend towards a higher rate of acute graft-versus-host-disease in patients with anti-recipient isohemagglutinins compared to those without (75% vs. 53%; p = 0.12), though not statistically significant. Rates of alloimmunization to minor red cell antigens were similar between the two groups. Few patients showed laboratory evidence of hemolysis at 12 months follow up. DISCUSSION AND CONCLUSIONS: Anti-recipient isohemagglutinins occur at low rates in ABO incompatible HSCT and are significantly more common in minor ABO incompatible transplant compared to bidirectional transplants. Larger cohort studies are needed to better understand the relationship between anti-recipient isohemagglutinins and HSCT outcomes.

Red cell exchange for patients with sickle cell disease: an international survey of current practices.

INTRODUCTION: Red cell exchange (RCE) therapy is increasingly used to treat patients with acute or chronic manifestations of sickle cell disease (SCD). However, little is known regarding the most safe and effective practice parameters associated with this particular therapy. METHODS: A SCD subcommittee of members of the American Society for Apheresis (ASFA) developed a 122-question survey and administered it via email to other ASFA members. The survey inquired about clinical indications for treatment, practice patterns, and transfusion policies for RCE when used for patients with SCD. RESULTS: Ninety-nine distinct institutions completed the survey. Twenty-one (21%) were from outside of the US. Twenty-two (22%) provided chronic transfusion therapy to >10 patients, and both adult (25%) and pediatric-focused services (20%) were represented. Common acute indications for RCE included acute chest syndrome, acute ischemic stroke, and pre-surgical prophylaxis. Common chronic indications included primary stroke prophylaxis, secondary stroke prophylaxis, and recurrent acute chest syndrome. Respondents most commonly set a post-RCE treatment target of 30% for the hematocrit and hemoglobin S levels, regardless of the therapeutic indication. Units for RCE were phenotypically matched in 95% of cases. About 40% of respondents reported using isovolemic hemodilution. CONCLUSIONS: This survey solicited the current practice variations in RCE from a diverse range of practice sites. Many sites reported similar practice patterns and challenges but some variations emerged. To our knowledge, this survey represents the largest and most in-depth investigation of the use of RCE for patients with SCD, and could inform future studies in the field.

Can we better predict delayed hemolytic transfusion reactions and hyperhemolysis in sickle cell disease?

Delayed hemolytic transfusion reactions (DHTR) occurring in individuals with sickle cell disease (SCD) are usually indolent but may rarely progress to life-threatening hemolysis known as hyperhemolysis syndrome (HHS), which can be difficult to diagnose and manage. We evaluate a predictive model for DHTR proposed by Drs. Pirenne and Yazdanbakhsh. A scoring system and nomogram were utilized in three individuals with SCD and delayed hemolysis, with one likely having HHS. The scoring system is based on identified risk factors for developing hemolysis from patient transfusion history, while the nomogram utilizes persistence of hemoglobin A (HbA) which is not innate to SCD patients. We propose a novel method for HbA estimation to facilitate application of the nomogram. Application of the recently published predictive scoring system revealed a low risk of developing DHTR in one patient and an intermediate risk in two patients. As serial HbA values are not routinely assessed, HbA measurements were only available in one of the three patients, though use of the nomogram predicted a high likelihood of DHTR. The recently published predictive score and nomogram yielded mixed results and should be interpreted with caution when predicting the risk of developing DHTR in individuals with SCD. Management of DHTR/HHS continues to be a challenge for transfusion medicine and hematology services standardized methods to facilitate their early diagnosis and treatment are warranted to improve the safety of blood transfusions in individuals with SCD.

COVID-19 in Africa: care and protection for frontline healthcare workers.

Medical staff caring for COVID-19 patients face mental stress, physical exhaustion, separation from families, stigma, and the pain of losing patients and colleagues. Many of them have acquired SARS-CoV-2 and some have died. In Africa, where the pandemic is escalating, there are major gaps in response capacity, especially in human resources and protective equipment. We examine these challenges and propose interventions to protect healthcare workers on the continent, drawing on articles identified on Medline (Pubmed) in a search on 24 March 2020. Global jostling means that supplies of personal protective equipment are limited in Africa. Even low-cost interventions such as facemasks for patients with a cough and water supplies for handwashing may be challenging, as is 'physical distancing' in overcrowded primary health care clinics. Without adequate protection, COVID-19 mortality may be high among healthcare workers and their family in Africa given limited critical care beds and difficulties in transporting ill healthcare workers from rural to urban care centres. Much can be done to protect healthcare workers, however. The continent has learnt invaluable lessons from Ebola and HIV control. HIV counselors and community healthcare workers are key resources, and could promote social distancing and related interventions, dispel myths, support healthcare workers, perform symptom screening and trace contacts. Staff motivation and retention may be enhanced through carefully managed risk 'allowances' or compensation. International support with personnel and protective equipment, especially from China, could turn the pandemic's trajectory in Africa around. Telemedicine holds promise as it rationalises human resources and reduces patient contact and thus infection risks. Importantly, healthcare workers, using their authoritative voice, can promote effective COVID-19 policies and prioritization of their safety. Prioritizing healthcare workers for SARS-CoV-2 testing, hospital beds and targeted research, as well as ensuring that public figures and the population acknowledge the commitment of healthcare workers may help to maintain morale. Clearly there are multiple ways that international support and national commitment could help safeguard healthcare workers in Africa, essential for limiting the pandemic's potentially devastating heath, socio-economic and security impacts on the continent.

Jk3 alloantibodies during pregnancy-blood bank management and hemolytic disease of the fetus and newborn risk.

BACKGROUND: The Kidd-null phenotype, Jk(a-b-), occurs in individuals who do not express the JK glycoprotein. Jk(a-b-) individuals can make an antibody against the Jk3 antigen, a high-incidence antigen present in more than 99.9% of most populations. This presents many challenges to the blood bank including identification of the antibody, masking of other antibodies, and how to provide transfusion support given the rarity of Jk3-negative blood products. Kidd antibodies may cause acute and delayed hemolytic reactions as well as hemolytic disease of the fetus and newborn (HDFN). In this article, we present a series of four practical cases of pregnant women with the anti-Jk3 alloantibody that demonstrate a range of clinical presentations of Kidd-related HDFN. STUDY DESIGN AND METHODS: We retrospectively reviewed the clinical and blood bank records for four patients and their newborns encountered at institutions in Tennessee, Missouri, Hawaii, and Guam with an anti-Jk3 identified during pregnancy. RESULTS: Two cases showed no significant evidence for HDFN, while two cases were of mild-to-moderate severity requiring early delivery due to elevated middle cerebral artery (MCA) flow velocities but requiring only phototherapy for hyperbilirubinemia. No intrauterine or neonatal transfusions were necessary. Anti-Jk3 alloantibody titers ranged from 2 to 128. CONCLUSION: Clinical manifestations of anti-Jk3 HDFN are generally mild to moderate. Anti-Jk3 titers were not found to correlate directly with HDFN severity. We suggest a titer of 16 to 32 as a cutoff for implementing enhanced monitoring of fetal MCA flow velocities, as such titers may be indicative of elevated HDFN risk.

Indwelling ports for prophylactic RBC exchanges in sickle cell patients: Comparison of bard and vortex ports.

INTRODUCTION: Red blood cell exchange (RCE) procedures are commonly used for stroke prevention in sickle cell disease (SCD) patients. We compared two different dual lumen ports used for RCE because differences between the port and catheter design may lead to functional variance. METHODS: We reviewed the RCE parameters of SCD patients following implantable port placement encountered at a single institution. Five Vortex and four Bard ports were used and compared. Patients were followed for 1-24 exchange procedures over 3-26 months performed between 2013 and 2015. RESULTS: Nine patients underwent 124 RCE procedures with no failures. A total of 74 exchanges used Vortex ports with a mean flow rate of 45.2 mL/min while 50 exchanges used Bard ports with a mean flow rate of 42.1 mL/min which was a significant difference (P = .002). A total of 85 exchanges with tPA administration preprocedure had a mean flow rate of 43.8 mL/min while 39 exchanges without had a mean flow rate of 45.4 mL/min which was not a significant difference (P = .19). CONCLUSION: Both the Bard and Vortex ports functioned well during our study period with no treatment failures, no significant complications requiring removal or replacement, and adequate mean flow rates. While the difference in mean flow rates was statistically significant between Vortex and Bard ports, there may not be a practical difference in performance. There also does not appear to be a significant benefit in flow rates with preprocedure tPA. We conclude that both ports may be a satisfactory choice for vascular access in SCD patients expected to undergo regularly scheduled RCE.

Choosing Wisely for apheresis.

The Choosing Wisely campaign has stimulated clinicians to think about the appropriateness of various tests and procedures, compelling physicians to make smarter, safer and more effective choices for high quality patient care and to reduce healthcare cost. The American Society for Apheresis (ASFA) strives to advance apheresis medicine through education, evidence-based practice, research and advocacy. To complement these shared missions, ASFA created a working group, consisting of representatives from the various ASFA committees, to produce recommendations for apheresis medicine that reflect the Choosing Wisely guiding principles. A diverse group of ASFA physician and allied health members reviewed, rated and ranked 9 original draft proposals. Additional revisions and refinements were made prior to external review and adoption of five final recommendations by the ASFA Board of Directors. The ASFA Choosing Wisely recommendations encourage apheresis practitioners, patients and donors to discuss and prioritize best clinical practices that avoid harm and waste while optimizing clinical benefit.