Acute hypotensive transfusion reaction during liver transplantation in a patient on angiotensin converting enzyme inhibitors from low aminopeptidase P activity

Emerging Evidence on Coronary Heart Disease Screening in Kidney and Liver Transplantation Candidates: A Scientific Statement From the American Heart Association: Endorsed by the American Society of Transplantation

Coronary heart disease is an important source of mortality and morbidity among kidney transplantation and liver transplantation candidates and recipients and is driven by traditional and nontraditional risk factors related to end-stage organ disease. In this scientific statement, we review evidence from the past decade related to coronary heart disease screening and management for kidney and liver transplantation candidates. Coronary heart disease screening in asymptomatic kidney and liver transplantation candidates has not been demonstrated to improve outcomes but is common in practice. Risk stratification algorithms based on the presence or absence of clinical risk factors and physical performance have been proposed, but a high proportion of candidates still meet criteria for screening tests. We suggest new approaches to pretransplantation evaluation grounded on the presence or absence of known coronary heart disease and cardiac symptoms and emphasize multidisciplinary engagement, including involvement of a dedicated cardiologist. Noninvasive functional screening methods such as stress echocardiography and myocardial perfusion scintigraphy have limited accuracy, and newer noninvasive modalities, especially cardiac computed tomography-based tests, are promising alternatives. Emerging evidence such as results of the 2020 International Study of Comparative Health Effectiveness With Medical and Invasive Approaches-Chronic Kidney Disease trial emphasizes the vital importance of guideline-directed medical therapy in managing diagnosed coronary heart disease and further questions the value of revascularization among asymptomatic kidney transplantation candidates. Optimizing strategies to disseminate and implement best practices for medical management in the broader end-stage organ disease population should be prioritized to improve cardiovascular outcomes in these populations.

Plasmin-mediated cleavage of high-molecular-weight kininogen contributes to acetaminophen-induced acute liver failure

Acetaminophen (APAP)-induced liver injury is associated with activation of coagulation and fibrinolysis. In mice, both tissue factor-dependent thrombin generation and plasmin activity have been shown to promote liver injury after APAP overdose. However, the contribution of the contact and intrinsic coagulation pathways has not been investigated in this model. Mice deficient in individual factors of the contact (factor XII [FXII] and prekallikrein) or intrinsic coagulation (FXI) pathway were administered a hepatotoxic dose of 400 mg/kg of APAP. Neither FXII, FXI, nor prekallikrein deficiency mitigated coagulation activation or hepatocellular injury. Interestingly, despite the lack of significant changes to APAP-induced coagulation activation, markers of liver injury and inflammation were significantly reduced in APAP-challenged high-molecular-weight kininogen-deficient (HK-/-) mice. Protective effects of HK deficiency were not reproduced by inhibition of bradykinin-mediated signaling, whereas reconstitution of circulating levels of HK in HK-/- mice restored hepatotoxicity. Fibrinolysis activation was observed in mice after APAP administration. Western blotting, enzyme-linked immunosorbent assay, and mass spectrometry analysis showed that plasmin efficiently cleaves HK into multiple fragments in buffer or plasma. Importantly, plasminogen deficiency attenuated APAP-induced liver injury and prevented HK cleavage in the injured liver. Finally, enhanced plasmin generation and HK cleavage, in the absence of contact pathway activation, were observed in plasma of patients with acute liver failure due to APAP overdose. In summary, extrinsic but not intrinsic pathway activation drives the thromboinflammatory pathology associated with APAP-induced liver injury in mice. Furthermore, plasmin-mediated cleavage of HK contributes to hepatotoxicity in APAP-challenged mice independently of thrombin generation or bradykinin signaling.

Pediatric Hemovigilance and Adverse Transfusion Reactions

Some types of transfusion reactions occur more frequently in the pediatric than the adult population. Allergic reactions are the most common, followed by nonhemolytic transfusion reactions; male children seem most susceptible to such reactions. Platelets are often implicated and pulmonary reactions are understudied in children. Clinical sequelae in neonates, such as bronchopulmonary dysplasia/chronic lung disease and intraventricular hemorrhage, have received increasing attention in relation to transfusion. There is a need to better understand the pathophysiology of transfusion reactions in neonatal and pediatric populations so preventive strategies can be undertaken. There is also a need for robust hemovigilance systems.

Profound Intraoperative Hypotension Associated With Transfusion via the Belmont Fluid Management System

This retrospective observational case series conducted at 2 large academic centers over a 4-year period consists of 15 cases of profound hypotension in surgical patients immediately after initiation of the Belmont Fluid Management System for rapid transfusion of blood products. Halting the infusion and administering vasoactive agents led to resolution of hypotension. Repeat transfusion with the Belmont system resulted in repeat hypotension unless counteracted with vasopressors. No etiology was elucidated. This represents the largest documented association of acute hypotensive transfusion reaction with any rapid infusion system in surgical patients.

Intraoperative Diagnosis and Management of Acute Hypotensive Blood Transfusion Reaction (AHTR): A Report of Two Cases

Case series

Patients: Female, 68 • Male, 86

Final Diagnosis: Acute hypotensive transfusion reaction

Symptoms: Hypotension

Medication: —

Clinical Procedure: —

Specialty: Anesthesiology

Hypotensive Transfusion Reaction Treated With Vasopressin in a Patient Taking an Angiotensin-Converting Enzyme Inhibitor: A Case Report

Hypotensive transfusion reactions, which account for almost 3% of all transfusion reactions, are associated with patients treated with angiotensin-converting enzyme inhibitors. The current hypothesis suggests that they are caused by bradykinin-induced vasodilation in the absence of allergic, hemolytic, or septic mechanisms. The hypotension observed frequently is unresponsive to conventional therapy with catecholamines. The suggested intraoperative management includes cessation of transfusion and washing red blood cells before blood replacement. We present a patient experiencing a severe intraoperative hypotensive transfusion reaction, unresponsive to epinephrine and norepinephrine, in whom we were able to restore blood pressure and continue the transfusion of blood and plasma by infusing vasopressin.

Clinical Pattern in Hypotensive Transfusion Reactions

BACKGROUND

Hypotensive transfusion reactions (HyTRs) may be underreported and have been associated with patients taking angiotensin-converting enzyme inhibitors (ACEIs) receiving poststorage leukoreduced blood products through negatively charged filters. Although bedside leukoreduction is no longer commonplace, HyTRs still occur and are insufficiently characterized in the prestorage leukoreduction era. We describe recently reported cases at our institution.

METHODS

We reviewed transfusion reaction records at Stanford Healthcare from January 2014 to April 2015. HyTRs were defined by National Health Safety Network Hemovigilance Module classification.

RESULTS

Eleven HyTRs occurred in 10 patients. All were adults (mean age 71.7 years; range 45-92 years), 7 were male, and all underwent major surgery 0 to 2 days before the reaction. Nine patients underwent cardiac or vascular surgery, and all 10 were taking ACEIs with the last dose taken within 48 hours of the transfusion reaction in 9 patients. Nine patients were on extracorporeal circuits within 24 hours before the reaction (median duration 180 minutes; range 87-474 minutes). In 5 reactions, the implicated unit was restarted with resultant recurrent hypotension. Implicated units included 9 packed red blood cells, 1 apheresis platelet, and 1 plasma frozen within 24 hours.

CONCLUSIONS

Contrary to what has been previously reported in the era of prestorage leukoreduction, HyTRs at our institution showed consistent patterns in patients at risk. Patients scheduled to undergo major surgery with cardiopulmonary bypass may benefit from earlier preoperative cessation of ACEIs or temporarily switching to an alternative drug class.

Transfusion reactions: prevention, diagnosis, and treatment

Blood transfusion is one of the most common procedures in patients in hospital so it is imperative that clinicians are knowledgeable about appropriate blood product administration, as well as the signs, symptoms, and management of transfusion reactions. In this Review, we, an international panel, provide a synopsis of the pathophysiology, treatment, and management of each diagnostic category of transfusion reaction using evidence-based recommendations whenever available.

Blood Products

Perioperative hemorrhage, anemia, thrombocytopenia, and coagulopathy are common in the surgical intensive care unit. As a result, blood product transfusion occurs frequently. While red blood cell, plasma, and platelet transfusions have a lifesaving role in the resuscitation of patients with trauma and hemorrhagic shock, their application in other settings is under scrutiny. Current data would suggest a conservative approach be taken, thus avoiding unnecessary transfusion and associated potential adverse events. New and developmental products such as prothrombin complex concentrates offer appealing alternatives to traditional transfusion practice—potentially with fewer risks—however, further investigation into their safety and efficacy is required before practice change can take place.

Washed RBCs prevent recurrent acute hypotensive transfusion reactions

OBJECTIVES

To examine whether a liver transplant patient, who was not taking an angiotensin-converting enzyme inhibitor and developed two episodes of hypotension with systolic pressure in the 50s within minutes of starting an RBC transfusion, may have had a disturbance in the production and metabolism of bradykinin and des-Arg(9)-BK.

METHODS

All patient information was obtained by reviewing the electronic medical record, the transfusion service database, and transfusion reaction investigation records.

RESULTS

The blood pressure returned to normal once the transfusions were discontinued. In an effort to mitigate the acute hypotension, the blood products were washed. Subsequently, the patient received three additional packed RBC transfusions without further incidents of hypotension.

CONCLUSIONS

Our experience suggests that washing the products was an acceptable and effective preventative measure to avoid further acute hypotensive transfusion reactions in patients unable to metabolize these vasodilators present in the donor units.

The development of a novel molecular assay examining the role of aminopeptidase P polymorphisms in acute hypotensive transfusion reactions

CONTEXT

Acute hypotensive transfusion reactions are potentially harmful adverse effects of transfusion attributable to bradykinin generation. They are most often seen in patients taking angiotensin-converting enzyme (ACE) inhibitors (ACE-Is) because of the role ACE plays in metabolizing bradykinin. However, a number of acute hypotensive transfusion reactions occur in patients not taking ACE-Is. Aminopeptidase P (APP), another important enzyme responsible for bradykinin degradation, is encoded by the polymorphic XPNPEP2 gene. Some polymorphisms in XPNPEP2 have been associated with decreased APP activity. However, the role that APP polymorphisms play in acute hypotensive transfusion reactions has never been investigated.

OBJECTIVE

To develop a molecular assay to examine for the C-2399A single-nucleotide polymorphism (SNP) in the APP gene, XPNPEP2, in patients experiencing acute hypotensive transfusion reactions unassociated with ACE-Is.

DESIGN

We developed an assay using polymerase chain reaction and DNA sequencing with primers targeted at XPNPEP2 (5'-GAGTATTATGTGGGGACCATCC-3' and 5'-ATGCCTCGCAGAGACAAGAG-3'). Polymorphism zygosity was determined by comparing the sense/antisense sequencing results. This assay was then applied to patients with acute hypotensive transfusion reactions not taking ACE-Is (n  =  4).

RESULTS

A C-2399A SNP assay was successfully developed and applied to patients with acute hypotensive transfusion reactions. In a pilot study, 2 patients (50%) were found to possess C-2399A polymorphisms. One was found to be homozygous, and the other was heterozygous.

CONCLUSIONS

Our C-2399A SNP assay can be used to study acute hypotensive transfusion reactions in patients not taking ACE-Is. Initial data indicate that the C-2399A polymorphism may be a contributing factor in such reactions. However, further studies are necessary to better define the role of APP polymorphisms in relation to acute hypotensive transfusion reactions unassociated with ACE-Is.