Thromboprophylaxis of Adult Medical Inpatients in St. John’s Newfoundland.

Introduction: Venothromboembolic disease (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), are causes of significant morbidity and mortality in hospitalized patients. Medical inpatients often have multiple risk factors for developing VTE and as a population have been shown to have significant rates of VTE ranging from 5–15% with approximately 75% of in hospital VTE occurring in non-surgical patients. Recent large randomized controlled trials have demonstrated the safety and efficacy of low molecular weight heparins (LMWH) in the prevention of VTE in this population. Despite the evidence of the effectiveness of this prophylactic treatment, numerous studies have demonstrated its underutilization in many at risk medical inpatient populations. We aim to establish rates of VTE prophylaxis in the population of at risk general medical inpatients in two acute care adult hospitals in the St. John’s area to assess if similar underutilization exists and if there is a need for future interventions to improve outcomes.

Methods: We used a modification of the inclusion/exclusion criteria of the MEDENOX trial to retrospectively identify consecutive medical inpatients at The General Hospital/St. Clare’s Mercy Hospital who were appropriate to receive VTE prophylaxis during January and February of 2005. Data was collected on demographics, VTE risk factors, and the use of any duration of low dose subcutaneous unfractionated heparin or low dose LMWH during their hospitalization. Two tailed t-tests were performed to identify any significant differences in demographics or VTE risk factors between the prophylaxis and non-prophylaxis groups.

Results: 114 medical inpatients were identified as being appropriate to receive pharmacologic VTE prophylaxis between Jan.1, 2005 and Feb. 28, 2005. 26 patients (23%) received some form of pharmacologic VTE prophylaxis. Of those who received prophylaxis, 19 patients (73%) received subcutaneous unfractionated heparin and 7 patients (27%) received LMWH. The only significant difference between the prophylaxis and non prophylaxis group was a higher proportion of patients with malignancy (27% vs 11% p=0.05) in the prophylaxis group.

Conclusion: This data demonstrates a significant underutilization of VTE prophylaxis in all at risk general medical patients in the two major adult acute care centres of the Eastern Health Board of Newfoundland. The data is consistent with the growing body of literature that exhibits that VTE prophylaxis in medical inpatients is deficient, with previously reported prophylaxis rates of only 20%–50%. Thus future work needs be done in translating “best practice” into “usual practice” as it relates to VTE prophylaxis.