Evaluation of a standardized protocol using lepirudin or argatroban for heparin-induced thrombocytopenia
Pre-post protocol study published in Cardiovascular & Hematological Agents in Medicinal Chemistry (2011)
Abstract
STUDY OBJECTIVE: To evaluate the effectiveness of our institutions heparin-induced thrombocytopenia (HIT) protocol in achieving a therapeutic activated partial thromboplastin time (aPTT) and to evaluate patient outcomes related to bleeding and thrombotic events before and after protocol implementation. DESIGN: Retrospective, single-center, pre- and post- assessment of a protocol previously approved at our institution. SETTING: 400-bed community hospital serving surrounding rural populations with emphasis in cardiothoracic surgery. PATIENTS: Retrospective chart review based on drug charge data identified 29 patients that received either argatroban or lepirudin for greater than 24 hours. Nineteen patients received either argatroban or lepirudin prior to HIT-protocol implementation, while the remaining ten received either drug after the HIT protocol was implemented. INTERVENTION: Implementation of HIT protocol occurred in March 2009. Patients were divided into pre-protocol and post-protocol groups. RESULTS: Primary outcome was to evaluate the number of therapeutic, subtherapeutic, and supratherapeutic aPTTs between two groups. In the pre-protocol group, aPTTs were therapeutic, subtherapeutic, and supratherapeutic 48.5% (164/338), 14.2% (48/338), and 37.2% (126/338) of the time, respectively. Meanwhile aPTTs in the post-protocol group were therapeutic, subtherapeutic, and supratherapeutic 46.6% (89/191), 22% (42/191), and 31.4% (60/191) of the time, respectively. The number of subtherapeutic aPTTs was statistically higher in the post-protocol group compared to the pre-protocol group. Secondary endpoints included the number of bleeding events and number of thrombotic events. None of the secondary endpoints reached statistical significance. Time to therapeutic aPTT was also evaluated: in the pre-protocol group median time (range) was 15 hours (2-108.6) compared to 8.1 hours (2.3-94.2) in the post-protocol group. CONCLUSIONS: Adoption and implementation of HIT protocol at our institution resulted in significantly more subtherapeutic aPTTs as compared to time prior to protocol. Although not statistically significant, the time required to obtain therapeutic aPTT was reduced by almost 50% after protocol implementation, which could be of clinical importance. Larger studies are needed to continue to assess if standardized protocols are effective in treatment of HIT.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Retrospective pre-post evaluation in 29 HIT patients showed that a standardized lepirudin/argatroban protocol shortened time-to-therapeutic-aPTT by ~50% (15 → 8.1 h median) but had more subtherapeutic aPTTs than pre-protocol practice.
Why This Matters for Hirudotherapy
This retrospective, single-center pre- and post-implementation study evaluated a standardized institutional HIT protocol using lepirudin or argatroban in 29 patients, assessing therapeutic activated partial thromboplastin time (aPTT) achievement and bleeding/thrombotic outcomes. The abstract reports that subtherapeutic aPTTs were statistically higher post-protocol, while secondary endpoints (bleeding, thrombotic events) did not reach significance; time to therapeutic aPTT was reduced by nearly half, although not statistically significant. The article's relevance to ASH's domain is limited: lepirudin is named only as one of two drugs in the protocol, and the abstract provides no information linking it to leeches, hirudin biology, or leech-derived therapy. CAVEAT: This is a small retrospective pre/post assessment at a single 400-bed hospital with only 10 post-protocol patients; outcomes are not isolated by drug, and the abstract contains no content on hirudotherapy or the leech secretome.
Citation
Evaluation of a standardized protocol using lepirudin or argatroban for heparin-induced thrombocytopenia.
Kennedy K et al. · Cardiovascular & Hematological Agents in Medicinal Chemistry, 2011
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