THE EFFECTIVENESS OF IMPLEMENTING THE WEIGHT-BASED HEPARIN NOMOGRAM AS A PRACTICE GUIDELINE

Objective: To determine the effectiveness of the nomogram in a communi ty hospital that implemented it as a practice guideline. Design: A non experimental, retrospective time series. Setting: A 600-bed community teaching hospital and regional referral center in Phoenix, Ariz. Patie nts: The study population included 591 consecutive patients with venou s thromboembolism, treated over a 5-year study period. Methods: During this period, the weight-based heparin nomogram was adapted into a pre printed order sheet and distributed to the hospital wards. The main ou t-come variables were the time to achieve a therapeutic activated part ial thromboplastin time and the rate of bleeding complications. Result s: Voluntary implementation of the nomogram steadily increased, reachi ng 94%. Comparison of the periods before and after 50% implementation demonstrated an increase in initial heparin dose (1185 vs 1420 U/h, P< .001), a decrease in time to achieve therapeutic activated partial thr omboplastin time (19.6 vs 11.8 hours), a decrease in the variance of t his parameter (25 vs 4 hours, P<.001), and no change in bleeding rates . The proportion of patients achieving a therapeutic activated partial thromboplastin time within 24 hours decreased from 97% to 86% when th e results from our previous randomized controlled trial (efficacy) are compared with the present results (effectiveness). Conclusions: The w eight-based heparin nomogram was well accepted by clinicians at our in stitution and led to more aggressive heparin dosing and improvements i n intermediate outcomes, without increasing bleeding. Mitigation of be nefit is likely to occur when practice guidelines are moved from the r ealm of efficacy research into clinical practice. Therefore, the effec tiveness of such measures requires monitoring.