A 57 year old woman with no history of cardiac disease develops substernal chest pressure during her routine hemodialysis session. The episode lasts about 5 minutes and resolves spontaneously before she arrives in the emergency room. Her vital signs are normal and her cardiac biomarkers are not elevated. Her EKG is shown below> Next step is:
A. Urgent cardiac catheterization
B. Heparin, plavix, aspirin and cardiac catheterization if cardiac biomarkers become elevated
C. Imaging stress test before considering catheterization
D. Admission for observation and telemetry monitoring
E. Correction of electrolyte abnormalities and reassurance
The correct answer for the Dialysis Quiz 12/30/11 is E. This patient has a clinical scenario highly concerning for heparin-induced thrombocytopenia (HIT). Characteritics of HIT include:
- 50% reduction in platelet count while exposed to heparin
- 5-10 days after exposure to heparin.
- Can be < 24 hours if heparin was given within the past 100 days
- HIT is associated with a ~50% risk of thrombosis.
- All patients with intermediate or high suspicion for HIT should receive alternative anticoagulation immediately.
- While lower risk, lovenox can cause HIT and should never be used in patients with suspected or known HIT.
- Argatroban and lepirudin are approved for treatment of HIT
- Fondaparinux has been studied for use in HIT but is renally excreted and not recommended for dialysis patients.
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•A 62 year old man on chronic hemodialysis (Monday-Wednesday-Friday) and a medical history of a prior DVT is admitted to the hospital for elective knee replacement. His warfarin had been stopped a few days prior and he is started on intravenous unfractionated heparin on admission. On his sixth hospital day, his platelet count falls to 75,000 from 225,000 the day prior.
In addition to discontinuing the IV heparin, you should do which of the following?
A. Await the results of an anti-PF4 assay before restarting anticoagulation
B. Transfuse platelets to prevent post-operative bleeding
C. Start subcutaneous lovenox immediately
D. Start subcutaneous fondaparinux immediately
E. Start IV argatroban immediately
Case Courtesy of Drs Rafael Bejar, Tyler Berzin, Rebecca Berman MD, and Chiadi Ndumele, Brigham and Women’s Hospital/Harvard Medical School
