Treatment of low-risk pulmonary embolism patients in a chest pain unit.
BACKGROUND
Several studies have proposed the Pulmonary Embolism Severity Index (PESI) as a risk stratification tool for discharge of low-risk pulmonary embolism (PE) patients from the emergency department (ED) and treatment as outpatients, but this has not become accepted standard of care in the United States. Chest pain units (CPUs) may serve as ideal locations for the treatment and risk-stratification of low-risk PE patients, thus avoiding lengthy inpatient stays while assuring patients are appropriate for outpatient therapy for PE. We sought to characterize the number of patients at our institution who may be eligible for a short stay in our CPU and then established a protocol for the treatment of low-risk patients in the CPU.


METHODS
We identified all patients admitted to the University of Utah Medical Center from the ED with a diagnosis of PE over the 6-year period between 2002 and 2007. We retrospectively reviewed the electronic medical records to identify clinical variables to calculate a PESI score for each patient. Patients who were considered to be low-risk, on the basis of PESI score (class I and II), were considered eligible for treatment in the CPU, and, on the basis of this, we estimated numbers of patients to be treated in the CPU and patient demographics. We determined results of transthoracic echocardiography (TTE) and bilateral lower extremity (BLE) venous duplex ultrasound for PE patients to estimate potential inpatient admission rates from the CPU. We reviewed the electronic medical records during the 30-day period after hospital admission for patient mortality. We then created a protocol for the treatment of these low-risk patients in the CPU.


RESULTS
A total of 545 patients were admitted with PE during the 6-year period. Of these patients, 282 were considered low risk and potentially appropriate for treatment of PE in the CPU. Of those, 43.3% were male, and the average age was 43.9 years (range: 14-92 years). Mortality was 0% for the low-risk group over the 30 days after hospital admission. A total of 108 patients had TTE performed and, of these, 30 had evidence of right heart strain. Ninety patients had BLE venous duplex and, of these, 15 had a deep venous thrombosis proximal to the popliteal veins. On the basis of our findings, we created a protocol for treatment of low-risk PE patients in the CPU. Patients who are low risk according to PESI score are admitted to the CPU with administration of low-molecular-weight heparin in the ED and initiation of oral anticoagulation therapy. Patients are monitored on telemetry for at least 12 hours, with performance of BLE duplex and TTE while in the CPU. Patients are admitted to an inpatient unit from the CPU if during their stay they exhibit unstable vital signs, a new arrhythmia, deep venous thrombosis proximal to the popliteal veins on BLE duplex, or signs of right heart strain on TTE. Patients who do not meet these criteria are considered appropriate for outpatient treatment and discharged with low-molecular-weight heparin and oral anticoagulation with thrombosis clinic follow-up. Given our findings from the retrospective chart review, we estimated that, at our institution, 4 patients per month would be eligible for treatment of PE in the CPU. With the findings on TTE and BLE duplex, we estimated that 25.3% of eligible patients would eventually require inpatient admission from the CPU.


CONCLUSIONS
We identified a number of low-risk patients who may be eligible for treatment of PE in our CPU. Given the resources of the CPU, this may serve as an ideal location for the treatment of low-risk PE patients and allow further risk stratification and consultation beyond that typically readily available in the ED. We described the creation of a protocol for the treatment of low-risk patients with PE in a CPU.
Utah Research for Observation Medicine Improvement Center, University of Utah, Salt Lake City, UT, USA. jbledsoe@utahep.com
Joseph
J
Bledsoe
David
D
Hamilton
Elizabeth
E
Bess
Jessica
J
Holly
Zachary
Z
Sturges
Troy
T
Madsen
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000553:Ambulatory Care / Q000458:organization & administration*; D000925:Anticoagulants / Q000627:therapeutic use*; D002985:Clinical Protocols; D019091:Critical Pathways / Q000592:standards*; D004333:Drug Administration Routes; D004452:Echocardiography; D005260:Female; D006495:Heparin, Low-Molecular-Weight / Q000627:therapeutic use*; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011655:Pulmonary Embolism / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D018570:Risk Assessment; D012720:Severity of Illness Index; D059039:Standard of Care; D018616:Ultrasonography, Doppler, Duplex
D000925:Anticoagulants; D006495:Heparin, Low-Molecular-Weight