Treatment
Management of Patients with Isolated HIT (HIT Without Thrombosis)
ÎIn patients with isolated HIT, the American College of Chest Physicians (ACCP) recommends the use of lepirudin or argatroban or danaparoid* over the further use of heparin or LMWH or initiation/continuation of a VKA. (1C)
ÎIn patients with isolated HIT who have normal renal function, the ACCP suggests the use of argatroban or lepirudin or danaparoid* over other nonheparin anticoagulants. (2C)
Management of HIT Complicated by Thrombosis (HITT)
ÎIn patients with HITT, the ACCP recommends the use of nonheparin anticoagulants, in particular lepirudin, argatroban, and danaparoid,* over the further use of heparin or LMWH or initiation/continuation of a VKA. (1C)
ÎIn patients with HITT who have normal renal function, the ACCP suggests the use of argatroban or lepirudin or danaparoid* over other nonheparin anticoagulants. (2C)
ÎIn patients with HITT and renal insufficiency, the ACCP suggests the use of argatroban over other nonheparin anticoagulants. (2C)
ÎIn patients with HIT and severe thrombocytopenia, the ACCP suggests giving platelet transfusions only if bleeding or during the performance of an invasive procedure with a high risk of bleeding. (2C)
ÎIn patients with strongly suspected or confirmed HIT, the ACCP recommends against starting VKA until platelets have substantially recovered (ie, usually to at least 150 x 109
/L) over starting VKA at a lower
platelet count and that the VKA be initially given in low doses (maximum, 5 mg of warfarin or 6 mg phenprocoumon) over using higher doses. (1C)
ÎThe ACCP further suggests that if a VKA has already been started when a patient is diagnosed with HIT, vitamin K should be administered. (2C)
ÎIn patients with confirmed HIT, the ACCP recommends that the VKA be overlapped with a nonheparin anticoagulant for a minimum of 5 days and until the international normalization ratio (INR) is within the target range over shorter periods of overlap and that the INR be rechecked after the anticoagulant effect of the nonheparin anticoagulant has resolved. (1C)
ÎDuration of VKA therapy in patients with HITT or HIT:
> For patients with HITT, the ACCP suggests VKA therapy or an alternative anticoagulant be continued for 3 months.
> For patients with HIT, the ACCP suggests VKA therapy or an alternative anticoagulant be continued for 4 weeks.
* Not available in the US.
