Introduction

Haematological disease may present de novo in critically ill patients as unexpected haemorrhage or thrombosis. Alternatively, abnormal and unexplained blood results maybe seen. More commonly patients with known disease, such as haematological malignancy, present for cardiothoracic surgery and then critical care admission. An understanding of the disease process and its treatment aids in the management of these patients.

Haemorrhage

Disseminated intravascular coagulation

Disseminated intravascular coagulation (DIC) is characterized by systemic intravascular activation of coagulation, leading to widespread intravascular thrombi and bleeding, owing to consumption of platelets and clotting factors. It may present in an acute or chronic form, and is triggered by many clinical conditions including sepsis, malignancy and trauma. Bleeding manifestations include petechiae and oozing from wound sites, intravenous lines, venepuncture sites and mucosal surfaces. Organ failure, secondary to tissue ischaemic injury from intravascular fibrin deposition, is also common. There is no single diagnostic test, but DIC should be considered whenever there is the combination of thrombocytopaenia, a prolonged prothrombin time (PT) and activated partial thromboplastin time (aPTT), low fibrinogen levels and evidence of accelerated fibrinolysis from the measurement of D-dimers.

Treatment should be aimed at identifying and removing/treating the underlying condition and providing multiorgan support, plus blood product support if there is active bleeding. In addition, in adults with severe sepsis and multiple organ failure, recombinant human activated protein C may be considered. There is no evidence to support the use of blood products if the patient is not bleeding, whatever the results of the laboratory tests.