In the United Kingdom, prehospital blood products are increasingly carried for the early resuscitation of hypovolaemia in patients who are shocked or in cardiac arrest. There is an association between hypocalcaemia and mortality in trauma patients, but no current national guidelines on the timing or dose of calcium replacement exist. The objective of this study was to establish the availability of prehospital blood products, and the current calcium replacement protocols used by UK prehospital services.A cross sectional survey of all UK air ambulances and additional prehospital critical care organisations was conducted in April-May 2022 via an on-line questionnaire. The survey asked 11 questions about availability of prehospital blood products, calcium replacement for patients requiring prehospital blood products, and the use of point of care testing.There was a 100% response rate with 20/22 UK air ambulances carrying blood products and five additional prehospital services identified. There were 15 different combinations of prehospital blood products. 23/25 services had a standard operating procedure for the replacement of calcium. This was recommended before any blood product administration in 5 services (22%), during or after the 1st unit in 5 services (22%), during or after the 2nd unit in 6 services (26%) and during or after the 4th unit in 7 services (30%). Only six services carried point of care testing and no services routinely used this to measure calcium levels in patients requiring prehospital blood products.In 2022, 91% of UK air ambulances carry prehospital blood products and there is significant variation between services in the combination of blood products provided. There is no consensus on the timing or dose of calcium replacement. Further prospective research should examine the association between traumatic bleeding and ionized calcium levels before and during blood product transfusion in order to produce more robust guidelines for routine calcium replacement. 

https://doi.org/10.1016/j.resplu.2022.100282

Pre-hospital blood products and calcium replacement protocols in UK critical care services: A survey of current practice

In-hospital acute resuscitation in trauma has evolved toward early and balanced transfusion resuscitation with red blood cells (RBC) and plasma being transfused in equal ratios. Being able to deliver this ratio in prehospital environments is a challenge. A combined component, like leukocyte-depleted red cell and plasma (RCP), could facilitate early prehospital resuscitation with RBC and plasma, while at the same time improving logistics for the team. However, there is limited evidence on the clinical benefits of RCP.To compare prehospital transfusion of combined RCP versus RBC alone or RBC and plasma separately (RBC + P) on mortality in trauma bleeding patients.Data were collected prospectively on patients who received prehospital transfusion (RBC + thawed plasma/Lyoplas or RCP) for traumatic hemorrhage from six prehospital services in England (2018-2020). Retrospective data on patients who transfused RBC from 2015 to 2018 were included for comparison. The association between transfusion arms and 24-h and 30-day mortality, adjusting for age, injury mechanism, age, prehospital heart rate and blood pressure, was evaluated using generalized estimating equations.Out of 970 recruited patients, 909 fulfilled the study criteria (RBC + P = 391, RCP = 295, RBC = 223). RBC + P patients were older (mean age 42 vs 35 years for RCP and RBC), and 80% had a blunt injury (RCP = 52%, RBC = 56%). RCP and RBC + P were associated with lower odds of death at 24-h, compared to RBC alone (adjusted odds ratio [aOR] 0.69 [95%CI: 0.52; 0.92] and 0.60 [95%CI: 0.32; 1.13], respectively). The lower odds of death for RBC + P and RCP vs RBC were driven by penetrating injury (aOR 0.22 [95%CI: 0.10; 0.53] and 0.39 [95%CI: 0.20; 0.76], respectively). There was no association between RCP or RBC + P with 30-day survival vs RBC.Prehospital plasma transfusion for penetrating injury was associated with lower odds of death at 24-h compared to RBC alone. Large trials are needed to confirm these findings. 

https://ccforum.biomedcentral.com/counter/pdf/10.1186/s13054-022-04279-4

Association of red blood cells and plasma transfusion versus red blood cell transfusion only with survival for treatment of major traumatic hemorrhage in prehospital setting in England: a multicenter study

The incidence of anti-Gya is known to be extremely rare, and only a few examples have been reported in Japanese persons and in Caucasians. This case history reports the first example of anti-Gya detected in a Chinese person. The propositus is an 83-year-old male patient whose anti-Gya was revealed because of incompatibility of all units of blood tested by a saline indirect antiglobulin test (SIAT). Although the antibody had a titer of 512 by SIAT, 10 units of Gy(a+) red cells were transfused without any adverse effect.

/pdf/the-first-example-of-anti-gya-detected-in-hong-kong-7jz20mtvp8.pdf

The first example of anti-Gya detected in Hong Kong.

How I use platelet transfusions.

Major haemorrhage is a leading cause of morbidity and mortality worldwide. Successful treatment requires early recognition, planned responses, readily available resources (such as blood products) and rapid access to surgery or interventional radiology. Major haemorrhage is often accompanied by volume loss, haemodilution, acidaemia, hypothermia and coagulopathy (factor consumption and fibrinolysis). Management of major haemorrhage over the past decade has evolved to now deliver a ‘package’ of haemostatic resuscitation including: surgical or radiological control of bleeding; regular monitoring of haemostasis; advanced critical care support; and avoidance of the lethal triad of hypothermia, acidaemia and coagulopathy. Recent trial data advocate for a more personalised approach depending on the clinical scenario. Fresh frozen plasma should be given as early as possible in major trauma in a 1:1 ratio with red blood cells until the results of coagulation tests are available. Tranexamic acid is a cheap, life‐saving drug and is advocated in major trauma, postpartum haemorrhage and surgery, but not in patients with gastrointestinal bleeding. Fibrinogen levels should be maintained > 2 g.l−1 in postpartum haemorrhage and > 1.5 g.l−1 in other haemorrhage. Improving outcomes after major traumatic haemorrhage is now driving research to include extending blood‐product resuscitation into prehospital care.

Major haemorrhage: past, present and future

1Transfusion Medicine, NHS Blood and Transplant, Oxford, UK 2Department of Haematology, Oxford University Hospitals NHS Foundation Trust, Oxford, UK 3Radcliffe Department of Medicine, University of Oxford, and NIHR Oxford Biomedical Research Centre, Oxford, UK 4Transfusion Laboratory Manager, Southampton University Hospitals NHS Foundation Trust, Southampton, UK 5Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK 6NIHR Surgical Reconstruction and Microbiology Research Centre, Birmingham, UK 7Department of Haematology, Guy's and St Thomas's Hospital, London, UK 8Transfusion Practitioner, NHS Lanarkshire, University Hospital Wishaw, Wishaw, UK 9National Services Scotland/Scottish National Blood Transfusion, Edinburgh, UK 10Medical director, Serious Hazards of Transfusion, Manchester, UK 11Lead Transfusion Practitioner, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK 12Transfusion Laboratory Manager, Royal Cornwall Hospitals NHS Trust, Truro, UK 13Transfusion Medicine, NHS Blood and Transplant, London, UK 14Barts Health NHS Trust, London, UK 15Blizzard Institute, Queen Mary University of London, London, UK

Haematological management of major haemorrhage: a British Society for Haematology Guideline

Dear Sir, We describe a case of a haemolytic transfusion reaction due to anti-Gya. The Gregory (Gya) blood group antigen was first described in a Czechoslovakian family by Swanson et al. (1967) and was assigned to the Dombrock blood group system when it was discovered that the Gy(a-) phenotype was the Dombrock null phenotype (Banks et al., 1995). The 10 antigens of the Dombrock system are expressed on the glycosylphosphatidylinositol (GPI)-linked Dombrock glycoprotein, DO (CD297). DO is encoded by the gene ART4, which comprises three exons spanning 14 kbps DNA at 12p13-p12 (Reid et al., 2012). The Gy(a-) phenotype results from mutations within, or the outsplicing of, exon 2 and is extremely rare in most populations, only being described in families of Eastern European (Romany) heritage and in Japan. The Gya antigen is thought to be highly immunogenic as all published reports of the Gy(a-) phenotype in pregnant women have resulted in alloimmunisation, leading to the production of anti-Gya. Published cases of anti-Gya in the literature report transfusions with variable outcomes (Clark et al., 1975; Massaquoi, 1975; Yamauchi et al., 1992; Mak et al., 1995; Takamatsu et al., 2005); therefore, the clinical significance of anti-Gya is currently unclear. We describe a haemolytic transfusion reaction in a multiple myeloma (MM) patient with anti-Gya and discuss the management of this patient, including recommendations for transfusion.

K. Dowling

Papers

Haematological management of major haemorrhage: a British Society for Haematology Guideline

Haemolytic transfusion reaction in a Gy(a-) patient with anti-Gya : a case report.