Hypersensitivity disorders in horses

Blood Transfusion in Equids—A Practical Approach and Review

Simple Summary

Transfusion medicine is an accessible, technically simple, and often lifesaving tool that can be used in both field and hospital settings, in cases of significant bleeding or anemia. A thorough understanding of the indications, methodology and complications of blood transfusion allows the practitioner to identify cases where administration of whole blood is necessary, and how to safely perform the transfusion. This review collects the current literature surrounding blood transfusion into one readily accessible document to allow clinicians a comprehensive understanding of all aspects of equine blood transfusion, while serving as a reference for performing these procedures.

Abstract

Transfusion medicine is a crucial part of equine intensive and critical care. Blood transfusions can save lives in both acute and chronic cases of anemia, hemorrhage, and hemolysis. It is vital to have a comprehensive theoretical and practical understanding of the techniques, implications, risks, and complications. This review covers the physiology and pathophysiology of conditions requiring transfusion, as well as step by step guidance for practitioners of all experience levels. This review is designed to serve as a practical reference for those who are treating horses in either the field or hospital setting. It aims to provide both theoretical background and easy to locate formulae with guidance that is easy to refer to in a critical situation. When risks and benefits are well understood, these techniques can be confidently employed in critical situations to improve outcomes and save lives.

Anaphylactoid reaction caused by sodium ceftriaxone in two horses experimentally infected by Borrelia burgdorferi

BACKGROUND

Lyme borreliosis is a disease transmitted by ticks to mammals, especially in horses and humans. Caused by a spirochete Borrelia burgdorferi, it can result in lameness, arthritis, carditis, dermatitis and neurological signs. Anaphylactoid reactions are severe responses caused by direct action of substances (drugs, toxins), which can pose risks to life. Still poorly documented in horses, these reactions are caused by the effects of inflammatory mediators such as histamine, kinins and arachidonic acid metabolites. The last two are the most clinically relevant for the species.

CASE PRESENTATION

The simultaneous occurrence of anaphylactoid reaction in two horses experimentally infected by Borrelia burgdorferi undergoing intravenous treatment with ceftriaxone sodium is reported. It was administered 4.7 × 10(8) spirochetes intradermal and subcutaneous applications in both horses to evaluate clinical aspects of the Lyme disease, 95 days before the application of sodium ceftriaxone. During the administration, one horse (a gelding) showed immediate and severe anaphylactoid symptoms such as urticaria, dyspnea, tachycardia, and eyelid edema, which were controlled by injecting dexamethasone. After 1 day, it expressed signs of abdominal discomfort, caused by severe bloat, which was treated surgically via celiotomy. Subsequently, this gelding had piroplasmosis and severe anemia, requiring treatment with an antimicrobial and blood transfusion. Second horse (a mare) showed signs of hypotension during the application of the antibiotic, which disappeared only when the application was interrupted. Days after the event, the mare developed moderate large colon bloat, which was treated with medication only. Subsequently the mare was evolved into the prodromal phase of laminitis in one of the forelimbs, which was treated for 10 days with non-steroidal anti-inflammatory and rheology modifying drugs and cryotherapy.

CONCLUSIONS

From the two cases presented here, it does appear that sodium ceftriaxone can induce anaphylactoid reactions in horses infected by Borrelia burgdorferi, which may evolve into colic syndrome, laminitis and the occurrence of opportunistic infections. However, further evidence should be collected in order to draw definite conclusions.