A new protocol using highly sensitive blood tests to determine whether someone is having a heart attack can reduce wait times and overcrowding in emergency departments, according to a study from UT Southwestern Medical Centre. The findings are particularly meaningful during the current coronavirus pandemic when many people with chest pain may be fearful of going to the hospital.
"Patients are more reluctant to come to the ER with heart-related symptoms during the COVID-19 outbreak. We do not want those with medical emergencies to avoid the hospital due to concern for risk from the virus," says cardiologist Dr Rebecca Vigen, assistant professor of internal medicine at UT Southwestern.
The research team led by Vigen found that a new protocol for using high sensitivity cardiac troponin testing can improve efficiency in the ER by more quickly determining which patients are not having a heart attack. Troponins are proteins released when the heart muscle has been damaged. The protocol incorporates the HEART score – history, electrocardiogram, age, risk factors, and troponin – an emergency department risk assessment tool that guides decisions on discharge and stress testing.
According to the US Centres for Disease Control and Prevention, chest pain is the most common reason for trips to the ER, resulting in 7m annual visits. "Our innovative strategy allowed us to 'rule out' heart attacks within one hour in more than half of the patients who were tested. This process is safe and improves the efficiency of evaluating patients with possible heart attacks," says Dr James de Lemos, professor of internal medicine at UT Southwestern and co-author of the study.
"Emergency room overcrowding has become an urgent health priority that is even more pressing in the current COVID-19 pandemic. Given the large size of the study and its performance during routine operations in our county hospital, we think the findings would apply to many busy U.S. emergency rooms," de Lemos adds.
The new protocol was first implemented in December 2017 at Parkland Memorial Hospital, a major safety net hospital in Dallas, and then in October 2018 at UT Southwestern's William P Clements Jr University Hospital. The study included 31,543 emergency room patients at Parkland from 1 January, 2017, to 16 October, 2018. Their mean age was 54, the population was racially and ethnically diverse, and 48% were women.
Abstract
Importance: High-sensitivity cardiac troponin T (hs-cTnT) protocols for the evaluation of chest pain in the emergency department (ED) may reduce unnecessary resource use and overcrowding.
Objective: To determine whether the implementation of a novel hs-cTnT protocol, which incorporated troponin values drawn at 0, 1, and 3 hours after ED presentation and the modified HEART score (history, electrocardiogram, age, risk factors), was associated with improvements in resource use while maintaining safety.
Design, Setting, and Participants: This retrospective cohort study from Parkland Health and Hospital System, a large safety net hospital in Dallas, Texas, included data on 31 543 unique ED encounters in which patients underwent electrocardiographic and troponin testing from January 1, 2017, to October 16, 2018. The hs-cTnT protocol was implemented in December 2017.
Main Outcomes and Measures: Resource use outcomes included trends in ED dwell time, troponin to disposition decision time (the difference between the first troponin draw time and the time an order was placed for inpatient admission, admission to observation, or discharge), and final patient disposition. Safety outcomes included readmission for myocardial infarction and death.
Results: In 31 543 encounters, mean (SD) patient age was 54 (14.4) years and 14 675 patients (48%) were female. Department dwell time decreased by a mean of −1.09 (95% CI, −2.81 to 0.64) minutes per month in the preintervention period. The decline was steeper after the intervention (−4.69 [95% CI, −9.05 to −0.33] minutes per month) (P for interaction = .007). The troponin to disposition time was increasing in the preintervention period by 1.72 (95% CI, 1.08 to 2.36) minutes per month; postintervention, the mean difference increased more slowly (0.37 [95% CI, −1.25 to 1.99 minutes per month; P value for interaction = .007]). The proportion of patients discharged from the ED increased after the intervention (48% vs 54%, P < .001). Thirty-day major adverse cardiac event rates were low and did not differ before and after the intervention.
Conclusions and Relevance: Implementation of a novel protocol incorporating serial hs-cTnT measurements over 3 hours with the Modified HEART Score was associated with reduction in ED dwell times and attenuation of temporal increases in time from troponin measurement to disposition. This or similar protocols to rule out myocardial infarction have the potential to reduce ED overcrowding and improve health care quality while maintaining safety.
Authors
Rebecca Vigen, Deborah B Diercks, Ibrahim A Hashim, Ambarish Pandey, Lin Zhong, Patricia Kutscher, Fernabelle Fernandez, Amy Yu, Bryan Bertulfo, Kyle Molberg, Jeffery C Metzger, Jose Soto, Dergham Alzubaidy, Lorie Thibodeaux, Jose A Joglar, Sandeep R Das, James A de Lemos
[link url="https://www.utsouthwestern.edu/newsroom/articles/year-2020/New-heart-attack-testing-protocol-expedites-treatment-in-er.html"]UT Southwestern Medical Centre material[/link]
[link url="https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2764661"]JAMA Network Open abstract[/link]