Assessment of Utilization of Outpatient Based Treatment for Low Risk Patients with Pulmonary Embolism in Two Community Teaching Hospitals

OBJECTIVE: Several randomized controlled trials and meta-analysis has proven safety and efficacy of outpatient based treatment in appropriately selected low-risk patients with pulmonary embolism (PE). Despite the fact that outpatient treatment has been proven safe, prior studies have shown that it is not commonly practiced. Our current multi-center study focuses on identifying practices of outpatient versus inpatient treatment of low risk PE patients in two community hospitals between 2018-2019.

METHODS: A retrospective chart review of the patients in two community hospitals with the principal discharge diagnosis of pulmonary embolism aged 18 years or older was conducted. The study period included February 2018 to February 2019. The high risk patients defined as simplified pulmonary embolism severity index (PESI) score of 1 or above were excluded from the study. Low risk patients were defined as with a simplified PESI score of 0. Criteria were established to determine the appropriateness of inpatient admission for low risk patients with PE. The group of low risk patients with thrombocytopenia (platelets less than 70,000/mm³), glomerular filtration rate (GFR) of less than 30 ml/ minute, international normalized ratio (INR) greater than 1.5, pregnancy, active bleeding as documented in the medical records, total bilirubin greater than 3.0 mg/dl, extreme obesity (weight greater than 150 kg), diagnosis of acute PE while on oral anticoagulation, requiring narcotics for chest pain, need for supplemental oxygen , poor social support or presence of concomitant extensive deep vein thrombosis were deemed appropriate for inpatient treatment. The patients without these baseline characteristics were considered appropriate for outpatient treatment.

RESULTS: The cohort comprised of 442 patients in two community hospitals. Among these, 172 patients had a simplified PESI score of 1 or above and were excluded from the study. The remaining 270 patients had a simplified PESI score of 0 and were considered low risk. Based on the study criteria, 54% (145 patients out of 270) of the low risk patients were deemed appropriate for outpatient treatment. Out of these, only 16% (23 patients out of 145) were treated at home. The remaining 84% (122 patients out of 145) of the low risk PE patients considered safe for outpatient treatment were actually treated as inpatient. The mean length of hospital stay for this group of patients was 3 days. Anti-coagulation therapy for those treated on outpatient basis was novel oral anticoagulants in 79% (18 patients out of 23) and low molecular weight heparin or warfarin in 21% (5 patients out of 23).

CONCLUSION: Our study demonstrates that majority of low risk PE patients deemed appropriate for outpatient based treatment are treated on inpatient basis. This study shows that there is a need to implement interventions to improve practices of outpatient management of appropriately selected low-risk PE patients.