Plasmapheresis and heparin reexposure as a management strategy for cardiac surgical patients with heparin-induced thrombocytopenia.
BACKGROUND
Heparin-induced thrombocytopenia (HIT) complicates the management of patients presenting for cardiac surgery, because high-dose heparin anticoagulation for cardiopulmonary bypass is contraindicated in these patients. Alternative anticoagulants are available, but there are concerns about dosing, efficacy, monitoring, thrombosis, and hemorrhage.


METHODS
A retrospective chart review between November 2004 and March 2008 retrieved perioperative clinical and laboratory data for 11 adult cardiac surgical patients with a preoperative history of HIT and a current positive antiheparin/platelet factor 4 (anti-HPF4) antibody titer, who were managed with plasmapheresis and heparin anticoagulation.


RESULTS
The median (interquartile range) preoperative anti-HPF4 antibody titer was 0.8 (0.7-2.2). Three of the 11 patients (27%) died of causes unrelated to HIT and 1 of these patients (9%) developed an ischemic foot, in the setting of cardiogenic shock, not thought to be HIT-related. A single plasmapheresis treatment reduced titers by 50%-84%, and 6 patients had negative titers after treatment; none of the 3 patients with reduced titers developed clinical HIT.


CONCLUSIONS
This case series describes an alternative management strategy using intraoperative plasmapheresis for patients presenting for cardiac surgery with acute or subacute HIT. Reducing antibody load can potentially decrease the thrombotic risk associated with high anti-HPF4 titers and decrease the urgency to initiate postoperative anticoagulation in this patient group at high risk of postoperative bleeding.
Welsby
Ian J
IJ
Department of Anesthesiology, Duke University Medical Center, DUMC Box 3094, Durham, NC 27710, USA. welsb001@mc.duke.edu
Um
John
J
Milano
Carmelo A
CA
Ortel
Thomas L
TL
Arepally
Gowthami
G
D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000009:adverse effects* / Q000627:therapeutic use*; D016063:Blood Loss, Surgical; D006348:Cardiac Surgical Procedures; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006493:Heparin / Q000009:adverse effects* / Q000627:therapeutic use*; D006801:Humans; D007511:Ischemia / Q000209:etiology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010956:Plasmapheresis; D010976:Platelet Count; D010978:Platelet Factor 4 / Q000032:analysis / Q000276:immunology; D011183:Postoperative Complications / Q000097:blood / Q000628:therapy; D012770:Shock, Cardiogenic / Q000150:complications; D013921:Thrombocytopenia / Q000139:chemically induced* / Q000188:drug therapy*; D016896:Treatment Outcome; D055815:Young Adult
D000925:Anticoagulants; D010978:Platelet Factor 4; D006493:Heparin