Department of Pharmaceutical Services, Beaumont Hospital, Detroit, Michigan 48073, USA.
Thromb Haemost. 2012 Nov;108(5):992-8. doi: 10.1160/TH12-05-0289. Epub 2012 Sep 5.
Establishing the diagnosis of heparin induced thrombocytopenia (HIT) is challenging as laboratory tests for HIT vary in specificity and availability. As HIT suspicion far exceeds confirmation of diagnosis, overtreatment is an emerging concern. This pilot study evaluated the impact of a HIT Recognition and Management Protocol on direct thrombin inhibitor (DTI) prescribing, outcomes, and cost. The primary endpoint was DTI cessation within 12 hours of receipt of negative HIT serology. An observational cohort study using a pre-post design was performed. Sixty-one patients were in the pre-period (before implementation) and 46 in the post-period (after implementation). DTI therapy was discontinued within 12 hours of negative serology in 19.4% of pre-period patients compared to 40% of post-period patients, p=.058. DTI therapy was discontinued within 24 hours of receipt of a negative PF4/heparin ELISA more often in the post-period; 7/23 (30.4%) pre-period patients versus 16/26 (61.5%) post-period patients, p <0.05. Protocol implementation resulted in a significant improvement in timely initiation of DTI therapy (within 12 hours of HIT antibody testing) in those with a moderate to high suspicion of HIT; 8/31 (25.8%) of pre-period patients versus 24/31 (77.4%) of post-period patients, p <0.0001. Thrombotic events occurred in significantly more patients in the pre-period as compared to the post-period; 21/61 (34.4%) versus 6/46 (13%), respectively, p = 0.01. Major bleeding was reduced by 6.6 % after protocol implementation. The projected annual cost savings from decreased inappropriate DTI use was over $450,000. Protocol implementation had a positive impact on DTI prescribing, outcomes and cost.
确定肝素诱导的血小板减少症（HIT）的诊断具有挑战性，因为 HIT 的实验室检测在特异性和可用性上存在差异。由于对 HIT 的怀疑远远超过了对诊断的确证，过度治疗成为一个新出现的问题。这项试点研究评估了 HIT 识别和管理方案对直接凝血酶抑制剂（DTI）处方、结果和成本的影响。主要终点是在收到 HIT 血清学阴性结果的 12 小时内停止使用 DTI。采用前后设计进行了观察性队列研究。61 例患者在前期（实施前），46 例患者在后期（实施后）。在前期，有 19.4%的患者在接受阴性血清学检查后 12 小时内停止使用 DTI，而在后期，这一比例为 40%，p=0.058。在后期，更多患者在收到阴性 PF4/肝素 ELISA 结果后 24 小时内停止使用 DTI 治疗；在前期有 7/23（30.4%）例患者，而在后期有 16/26（61.5%）例患者，p<0.05。方案实施后，在高度怀疑 HIT 的患者中，及时开始 DTI 治疗（在 HIT 抗体检测后 12 小时内）显著改善；在前期有 8/31（25.8%）例患者，而在后期有 24/31（77.4%）例患者，p<0.0001。在前期，与后期相比，发生血栓事件的患者明显更多；分别为 21/61（34.4%）和 6/46（13%），p=0.01。实施方案后，大出血减少了 6.6%。由于减少了不适当的 DTI 使用，预计每年可节省超过 45 万美元的成本。方案实施对 DTI 的处方、结果和成本产生了积极影响。
