Treatment of HIT
(NEJM 2015;373:252; Blood Adv 2018;2:3360)
Discontinue heparin
(incl. flushes, LMWH Ppx, heparin lines). Avoid plts (anecdotal link w/ thrombosis); if given warfarin, give vit K to reverse, prevent warfarin skin necrosis.
Nonheparin anticoag
(argatroban, bivalirudin; NEJM 2013;368:737) regardless of thrombosis; start warfarin when plt >150k, overlap ≥5 d or DOAC (Blood 2017;130:1104)
⊕ thrombosis (HITT):
anticoagulate for ≥3–6 mo
⊖ thrombosis (HIT):
screen for DVT; unclear duration of subsequent anticoag (until plt count recovers, often ~2–3 mo if no clot); 25–50% thrombosis rate w/in 30 d