Evaluating the Outcomes of Quality Improvement Initiatives of a Multi-Disciplinary Heparin-Induced Thrombocytopenia (HIT) Task Force.
Authors: Davis Elaine A. , Frame James Norman , Wang Ying , Reed Joan 
Published: October 2019

Background: HIT is an antibody-mediated adverse effect of heparin associated with a high frequency of thromboembolic complications (TEC).

Objectives/Setting: To assess institutional progress in 6 quality improvement HIT outcome metrics. In 2001, a multi-disciplinary HIT Task Force was formed at the Charleston Area Medical Center, a tertiary-care medical center. Quality initiatives included a reduction of heparin exposures, development of standardized guidelines/order sets for diagnosis/treatment accessible via a HIT intranet website and the establishment of an IRB-approved HIT patient registry to be used for research and quality improvement (Blood.102:750a, 2003). Six outcome measures were selected by the HIT Task Force to evaluate progress in the quality initiatives (Table).

Methods: Retrospective review of registry data of patients treated for clinical HIT at this institution 1999–2004. Yrs. 1999–2002 were considered baseline during the era of increasing HIT awareness/Task Force establishment, 2003–2004 were considered the initial reassessment period.

Patients: 436 patients, mean age 67 yrs (26–92), female 215/436 (49%), admission type: cardiac surgery 294/436 (67%), non-cardiac surgery 38/436 (9%), non-surgical 104/436 (24%).

Results: The frequency of new thrombotic/new ischemic events after HIT diagnosis, frequency of amputation and warfarin initiation upon adequate platelet recovery showed statistically significant improvement (Table). The frequency of presentation with thrombosis was trending toward a significant change. All cause mortality and frequency of patients receiving treatment with a direct thrombin inhibitor (DTI) or heparinoid therapy within one day of “HIT suspected” improved, but not at a statistically significant level.

Conclusions: The results of these analyses establish the value of a multi-disciplinary HIT Task Force in leading hospital-based improvements for strategically-defined outcomes relevant to HIT patient care. Specifically, these efforts resulted in a statistically significant 87% relative reduction in amputations, a 46% relative reduction in the development of a new TEC/new ischemic event after HIT diagnosis and a 10% relative increase in instituting warfarin therapy upon platelet count recovery. A statistically non-significant 21% relative reduction in all-cause mortality, an 18% relative reduction in HIT patients presenting with a TEC and a 4% relative increase in the frequency of instituting a DTI within 1 day of first suspecting HIT were also observed. These findings are being used by the HIT Task Force to guide their activities for 2005.

Outcome Metrics 1999–2002 2003–2004 P-value N 232 204 Presentation with thrombosis 107/232 (46.1%) 77/204 (37.8%) 0.080 New thrombosis/ischemic event after HIT diagnosis 36/232 (15.5%) 17/204 (8.3%) 0.022* Amputation 8/232 (3.45%) 1/204 (0.49%) 0.041* DTI within 1 day of “HIT suspected” 120/185 (64.9%) 131/194 (67.5%) 0.593 Warfarin initiation upon platelet recovery ≥ 100,000/mm3 123/153 (80.4%) 147/165 (89.1%) 0.030* All-Cause Mortality 49/232 (21.1%) 34/204 (16.7%) 0.243