SummaryMajor vascular surgery is frequently associated with significant blood loss and coagulopathy. Existing evidence suggests hypofibrinogenaemia develops earlier than other haemostatic deficiencies during major blood loss. The purpose of this study was to assess whether the use of an infusion of fibrinogen concentrate to prevent and treat hypofibrinogenaemia during surgery resulted in satisfactory haemostasis, removing or reducing the need for blood component transfusion. Twenty patients undergoing elective extent‐4 thoraco‐abdominal aortic aneurysm repair were randomly allocated to receive either fresh frozen plasma or fibrinogen concentrate to treat hypofibrinogenaemia during surgery. Coagulation was assessed during and after surgery by point‐of‐care and laboratory testing, respectively, and treatment was guided by pre‐defined transfusion triggers. Despite blood losses of up to 11,800 ml in the patients who received the fibrinogen concentrate, none required fresh frozen plasma during surgery, and only two required platelet transfusions. The median (IQR [range]) allogeneic blood component administration during surgery and in the first 24 h postoperatively was 22.5 (14–28 [2–41]) units in patients allocated to fresh frozen plasma vs. 4.5 (3–11[0–17]) in patients allocated to fibrinogen concentrate (p = 0.011). All patients in both groups were assessed by the surgeon to have satisfactory haemostasis at the end of surgery. Mean (SD) postoperative fibrinogen concentrations were similar in patients allocated to fresh frozen plasma and fibrinogen concentrate (1.6 (0.3) g.l−1 vs. 1.6 (0.2) g.l−1; p = 0.36) but the mean (SD) international normalised ratio and activated partial thromboplastin time ratio were lower in patients allocated to fresh frozen plasma (1.1 (0.1) vs. 1.8 (0.3); p < 0.0001 and 1.1 (0.2) vs. 1.7 (0.5); p = 0.032, respectively). Fibrinogen concentrate may be used as an alternative to fresh frozen plasma in the treatment of coagulopathy during thoraco‐abdominal aortic aneurysm repair.

We thank Drs Bader and Ranier for their interest in our case report. They raise 2 main questions—whether it is appropriate to maintain a normal fibrinogen concentration during major vascular surgery rather than waiting until surgical hemostasis has been obtained, and whether ethics committee approval and patient consent were obtained for frequent ROTEM measurements and the use of fibrinogen concentrate. It has been our routine practice for over a decade to undertake frequent ROTEM measurements during thoracoabdominal aortic aneurysm surgery, and in recent years our aim has been to maintain a normal plasma fibrinogen concentration during surgery. The FIBTEM MCF range of 9-25 mm referred to by Drs Bader and Ranier is the normal range for this parameter. In practice, our aim of maintaining a normal fibrinogen concentration (≥1.5 g/L) meant that we aimed for a FIBTEM MCF ≥9 mm. We perform type IV thoracoabdominal aortic aneurysm surgery1Richards J.M. Nimmo A.F. Moores C.R. et al.Contemporary results for open repair of suprarenal and type IV thoracoabdominal aortic aneurysms.Br J Surg. 2010; 97: 45-49Crossref PubMed Scopus (31) Google Scholar without the use of a bypass circuit or full heparinization. A single dose of heparin (5,000 U) is given before aortic clamping. Hypothermia (minimum temperature 32-33°C) is used during the period of ischemia of the liver, bowel, and kidneys. It is our experience that not treating coagulation abnormalities, such as hypofibrinogenemia or severe thrombocytopenia, until the end of the surgery is associated with severe microvascular bleeding during surgery and increased blood loss. Severe diffuse bleeding in this situation can make it difficult to determine if there is adequate surgical hemostasis. Therefore, we aim to correct these coagulation abnormalities during surgery. A similar approach has been adopted by other units undertaking this type of surgery.2Ockert S. Riemensperger M. von Tengg-Kobligk H. et al.Complex abdominal aortic pathologies: Operative and midterm results after pararenal aortic aneurysm and type IV thoracoabdominal aneurysm repair.Vascular. 2009; 17: 121-128Crossref PubMed Scopus (4) Google Scholar Drs Bader and Ranier suggested that the infusion of fibrinogen concentrate is not helpful. We disagree with this interpretation for 3 reasons: FIBTEM MCF >9 mm was achieved successfully (as shown in Fig 2 of our case report), satisfactory hemostasis was achieved clinically, and it was not necessary to give fresh frozen plasma (FFP). They also described our administration of fibrinogen concentrate as pre-emptive. Again we disagree because fibrinogen concentrate was administered only in response to pathologic FIBTEM MCF values. Cell salvage with centrifugation and washing indeed removes most of the fibrinogen, other coagulation factors, and platelets from shed blood to produce concentrated red cells. However, not using cell salvage results in the same loss of fibrinogen, other coagulation factors, and platelets plus the additional loss of red blood cells. Fibrinogen concentrate has a marketing authorization (license) for the treatment of hypofibrinogenemia. In some European Union countries, where the marketing authorization is for the treatment of congenital and acquired fibrinogen deficiencies, fibrinogen concentrate has been used widely in bleeding surgical patients for many years and is regarded as the standard of care for the treatment of patients with acquired fibrinogen deficiency. In other countries, including the UK, the marketing authorization currently is only for the treatment of congenital fibrinogen deficiency. However, fibrinogen concentrate is used in the UK for the treatment of some bleeding patients with acquired hypofibrinogenemia because of concerns about the safety of cryoprecipitate and FFP. The use of fibrinogen concentrate to treat acquired hypofibrinogenemia is included in current guidelines from the British Committee for Standards in Haematology3Levi M. Toh C.H. Thachil J. et al.Guidelines for the diagnosis and management of disseminated intravascular coagulation British Committee for Standards in Haematology.Br J Haematol. 2009; 145: 24-33Crossref PubMed Scopus (691) Google Scholar and the Association of Anaesthetists of Great Britain and Ireland.4Association of Anaesthetists of Great Britain and IrelandBlood transfusion and the anaesthetist: Management of massive haemorrhage.J Anesth. 2010; 65: 1153-1161Google Scholar The patients described in the case report were not involved in a research study; therefore, ethics approval was not sought. The management of the patients was identical to our previous routine management of patients having repair of type IV thoracoabdominal aortic aneurysm apart from our use of fibrinogen concentrate rather than FFP to treat hypofibrinogenemia. Our use of fibrinogen concentrate was in accordance with the General Medical Council's guidance on prescribing medicines for use outside the terms of their licence,5General Medical CouncilGood practice in prescribing medicines—Guidance for doctors.http://www.gmc-uk.org/guidance/ethical_guidance/prescriptions_faqs.asp#10Google Scholar and this guidance does not suggest that written consent is required. However, the patients provided written consent to the publication of the case report. Drs Bader and Ranier also referred to the cost of fibrinogen concentrate. The cost of fibrinogen concentrate in some countries, including the UK, is lower than the range they stated, and the true costs of using allogeneic blood products often are underestimated.6Shander A. Hofmann A. Gombotz H. et al.Estimating the cost of blood: Past, present, and future directions.Best Pract Res Clin Anaesthesiol. 2007; 21: 271-289Abstract Full Text Full Text PDF PubMed Scopus (161) Google Scholar However, a comparison of the costs of different strategies of managing impaired hemostasis during surgery was beyond the scope of our case report. Is It Necessary to Maintain Fibrinogen During Hypothermia and Major Bleeding in Vascular Surgery?Journal of Cardiothoracic and Vascular AnesthesiaVol. 26Issue 5PreviewIn the case reports by Morrison et al,1 3 patients undergoing open thoracoabdominal aneurysm repairs received a continuous infusion of purified human plasma–derived fibrinogen concentrates (CSL Behring, Marburg, Germany) under the guidance of the FIBTEM assay on ROTEM (TEM International, Munich, Germany). There are some concerns about these cases. Full-Text PDF

i p c fi c b l s TYPE IV THORACOABDOMINAL aortic aneurysm (TAAA) repair is a major vascular procedure that involves eplacing the native abdominal aorta, from the level of the diahragm to the aortic bifurcation, with a synthetic graft. During urgery there is a period of complete ischemia of the liver, bowel, nd kidneys followed by reperfusion of these organs and a more rolonged period of pelvic and lower limb ischemia. The operaion is associated with large blood loss, often exceeding the paient’s intravascular volume. Hemostasis usually becomes seerely impaired during surgery as the concentrations of fibrinogen, ther coagulation factors, and platelets in the patient’s blood are ecreased by dilution, consumption, hyperfibrinolysis, and the ffects of visceral ischemia and reperfusion.1,2 In addition, patients ndergoing TAAA repair may be receiving antiplatelet agents, uch as aspirin and clopidogrel, and they usually receive anticogulants, such as heparin, during surgery. In an attempt to correct oagulopathy during surgery, infusions of blood components, such s fresh frozen plasma (FFP) and cryoprecipitate, often are used. owever, the efficacy of FFP has been questioned,3-5 and the transfusion of allogeneic blood components carries risks, including incompatibility reactions, immunosuppression, transfusionrelated acute lung injury and the transmission of bacterial, viral, and prion infections. The UK Government’s Advisory Committee on the Safety of Blood, Tissues and Organs (SaBTO) has recommended that the use of UK-derived FFP should cease because of the concerns regarding variant Creutzfeldt-Jakob disease.6 Cryorecipitate has been withdrawn from use in many European Union ountries and its continued use in the UK is under review by aBTO. Fibrinogen concentrate is a purified, virus-inactivated, plasmaerived product that may be used as an alternative source of brinogen to cryoprecipitate and FFP.7 Its advantages include a lower risk of transmitting infection, no requirement for matching to the patient’s blood group, and it may be stored at room temperature, thus avoiding delay owing to thawing. During bleeding, fibrinogen typically reaches critically low levels before platelets and other coagulation factors.8-10 In addition, the coagulopathy associated with the administration of synthetic colloid intravenous fluids may be attributable principally to impaired fibrinogen polymerization.11 Thus, in some circumstances, fibrinogen replaceent alone may be sufficient to maintain satisfactory hemostasis. Three recent patients undergoing elective type IV TAAA repair

A case of botulism is reported in a heroin-abusing parturient who initially presented with lethargy and slurred speech. The diagnostic difficulty, complications, intensive care and anaesthetic management of this case are discussed, with particular reference to the pregnancy and the effects of both botulism and its empirical treatment on the fetus. A short review is provided of a condition that has seen a marked increase in its incidence since 2000.