Usefulness of a Weighted-based, Patient-Specific Nomogram for Intravenous Heparin Therapy in Ischemic Stroke Patients

ABSTRACT

BACKGROUND: Despite the lack of supporting evidence, intravenous heparin is still given frequently in the treatment of cerebral ischemia. However, there is only one study for the use of heparin nomogram in ischemic stroke or TIA. We evaluated the usefulness of a patient-specific, as well as weight-based, nomogram for the intravenous heparin in patients with ischemic stroke or TIA. METHODS: From Sep. 2004 to Sep. 2005, we recruited ischemic stroke patients treated according to the specifically designed heparin nomogram. The therapeutic range (TR) of activated partial thromboplastin time (aPTT) and dose adjustment were specified as a ratio of each patient's baseline aPTT. The first time to achieve TR (TR-time), to exceed therapeutic threshold (TE-time) and the fraction of time in TR (total time in TR/total time of heparin use, %) were analyzed. RESULTS: A total of 45 patients were included. The mean fraction of time in TR was 72.7+/-14.4%. Although TR-time and TE-time did not differ according to the use of bolus injection, the fraction of first aPTT at 6 hours after start of infusion in TR was higher with bolus than without bolus (84.8 vs. 58.3, p<0.05). CONCLUSIONS: Our nomogram could achieve and maintain therapeutic heparin anticoagulation effectively. Initial bolus injection may be better to achieve therapeutic anticoagulation more rapidly.