Localized Intravascular Coagulopathy
Slow-flow vascular malformations, especially those with a large venous component can frequently be complicated by intralesional thrombosis and if ectatic vessels are connected to larger feeding veins this can put patients at risk for venous thromboembolism (VTE)5-11. Although the mechanism is not fully elucidated, venous stagnation can lead to activation and consumption of coagulation factors and platelets and result in localized intravascular coagulopathy (LIC). Pain is often correlated to LIC and is a common symptom of slow-flow vascular malformations resulting in decrease of quality of life and worse outcomes12,13. Pain in this group is complex occurring in the acute and chronic setting often associated with intralesional thrombi. The pain may also involve several contributing factors which include chronic venous insufficiency, inflammation, infection, arthritis, and neuropathic pain14.
LIC may worsen during a surgical or interventional procedure where the abnormal vasculature is perturbed leading to post-operative bleeding or thrombotic complications. Large excisions or prolonged intravascular procedures seem to be the highest risk procedures. There are no evidence-based guidelines for peri-operative management of LIC to mitigate the risk of hematologic complications. Sirolimus has been shown to reduce the coagulopathy and for minor procedures these patients may not require additional anticoagulation15. However, for complex surgical procedures and in patients with laboratory evidence of LIC, anticoagulation before and after the procedure may be warranted16.
Recognizing pediatric and adult patients with vascular tumors and malformations that are predisposed to coagulopathy is important. The rapidly growing field of surgical and medical management of vascular anomalies include medications that may improve or worsen the coagulopathy. Early identification will help improve outcomes in this patient population. Although there are no consensus guidelines, this review will help provide guidance in the therapeutic approach for management of coagulopathy in patients with vascular anomalies based on our current practice and review of the available literature.
2 | DIAGNOSTIC APPROACH
Appropriate management relies on accurate diagnosis. Historical data of the vascular malformation such as first appearance, growth, and aggravating factors are important. Physical exam, imaging and laboratory evaluation are essential in diagnosis and determining what treatment, if any, is needed. Conventional coagulation parameters that include complete blood count (CBC), prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, and D-dimer vary in specific vascular anomalies that are predisposed to coagulopathy (Table 1).
3 | CONSULTATION WITH THE HEMATOLOGIST