Plus-Hex CLINICAL

Ashley Johnson , RVN

Internal Medicine department , Royal Veterinary College

ENVELOPE johnsona150 @ gmail . com

Ashley qualified as an RVN in 2017 . She began in first opinion before moving to the Internal Medicine department of the Royal Veterinary College . After delving into the world of veterinary medicine , she became interested in immune-mediated diseases . Ashley is passionate about conservation and would like to volunteer abroad .

ABSTRACT Immune-mediated thrombocytopenia ( IMTP ) is a life-threatening condition . Although it is not unheard of in felines , it is seen most commonly in canines ( Donoghue , 2019 ). IMTP is a common disease in veterinary medicine and can affect any breed or age of dog but is most common in cocker spaniels , toy poodles , and middleaged female dogs ( Gorman , 2021 ).

Management of IMTP includes immunosuppressive and steroid treatment alongside a range of nursing care considerations . It is important that , as veterinary nurses , we understand the underlying physiology of the disease in order to best treat it . This article will provide an overview of IMTP and highlight key aspects of nursing care we can put to use in practice .

Keywords IMTP , immune-mediated thrombocytopenia , platelets , haemostasis

Introduction

Immune-mediated thrombocytopenia ( IMTP ) is a condition where the body ’ s immune system starts to damage and destroy its own platelets , and is classed as either a primary or secondary condition . Primary IMTP has no known cause and is therefore referred to as being idiopathic .

Secondary IMTP occurs when there is a separate trigger or underlying cause . Large cells called megakaryocytes located within the bone marrow constantly produce platelets which are released into the bloodstream to support haemostasis . Haemostasis is the stoppage of bleeding and has three stages that occur within a short amount of time . Once haemostasis has happened , the repair of the tissue can start to take place ( LaPelusa & Dave , 2020 ).

IMTP is one of the most common immune-mediated conditions seen in practice to date ( Sellon , 2011 ). Platelets are vital for the formation of blood clots . They form together into a plug to help reduce and stop blood flow . The normal circulating platelet count at any one time can vary between 200,000 and 500,000 platelets per microlitre of blood . These platelets can last between 8 and 12 days and , once the old platelets are no longer of use , the spleen produces cells called phagocytes , which absorb the old cells and dispose of them , thereby creating space for a new batch ( Brooks , 2003 ).

Phagocytosis is a naturally occurring process where phagocytes dispose of healthy platelet cells . This happens when immunoglobulins ( antibodies produced by white blood cells ) attach themselves to the outside of the platelet , thinking it is a foreign invader , and aids its destruction ( Pullen , 2015 ). During IMTP , phagocytosis occurs 10 times faster than the normal rate . When the platelet count is reduced to between 20,000 and 50,000 platelets per microlitre of blood , spontaneous bleeding and bruising occurs ( Brooks , 2003 ).

VOL 37 • May 2022

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