Advanced practice provider–led clinic for care transitions in newly diagnosed venous thromboembolism: establishment and utilization

Background Patients with suspected or newly diagnosed venous thromboembolism (VTE) are often referred to the emergency department (ED) for management, where anticoagulation is initiated. However, when the patient is judged to be suitable for outpatient management, counseling and follow-up specialty care are frequently suboptimal. Objectives To establish an advanced practice provider (APP)–led rapid follow-up clinic to improve transitions of care for patients with newly diagnosed deep vein thrombosis or low-risk pulmonary embolism and to provide continued specialty care and support, including management of complications and medication access issues. Methods In order to address this gap in transition of care, we developed an APP-led clinic with a mandate to improve quality and safety in the outpatient setting for patients with acute VTE. Results In the first 2 years, a total of 234 patients were evaluated, of whom data were standardized and reviewed for 229. Utilization steadily increased over time, with at least 10% of patients requiring financial medication assistance over both years. Seventy-two percent of patients were referred from the ED in the first year and 59% in the second year, and referrals from non-ED outpatient specialties increased. Data on deviations from standard care identified in referred patients were collected in the second year and found in 19 (12.7%) of cases. These included unnecessarily prescribed or changed anticoagulants, dosing errors, misclassification of thrombosis, and other deviations. Patient demographic data also demonstrated increasing diversity of the patient population over time, with increased utilization by Hispanic and African American patients in the second year. This highlighted the need for better patient education material translations into Spanish, which is a future aim. Conclusion In summary, the APP-led VTE Transition Clinic was feasible and grew quickly in utilization, diversity of referrals, and diversity of patients served.


| I N T R O D U C T I O N
Patients with suspected or newly diagnosed venous thromboembolism (VTE) are often sent to the emergency department (ED) for management, where they are started on anticoagulation. Time is limited for counseling and continued support for patients on new prescribed anticoagulation, as is access to specialty care.
Evidence supports treating most patients with VTE as outpatients [1]. Resources exist to support safe and comprehensive transitions of care in these patients, such as those provided by the Anticoagulation Forum [2]. However, there is hesitancy among some healthcare providers to manage patients with these morbid acute conditions on highrisk medications without appropriate follow-up. In the era of direct oral anticoagulants, the financial barriers associated with appropriate anticoagulation further complicate management. Rapid access to specialized care is limited, and many patients do not have access to specialized follow-up immediately after discharge.
Transitions of care provided by hematology providers allow for immediate assessment of appropriateness of anticoagulation, counseling on anticoagulation risks and benefits, and assistance in navigating barriers to medication access. Additionally, connecting to a specialty provider provides an ongoing resource to prevent repeat ED visits for complications that can be managed as an outpatient, such as continued pain or nonmajor bleeding. An initial discussion regarding the etiology of the episode can help patients develop a framework for their new diagnosis and long-term implications. Specialty providers are also able to help with procedural planning and care for patients in special populations, such as pregnant women, patients on hormone therapy, and patients with cancer.
A similar transition of care gap was identified in stroke follow-up and prevention of recurrent stroke at a midwestern Comprehensive Stroke Center [3]. In 2014, in response to this gap, an advanced practice provider (APP)-led clinic was developed, wherein patients were directly scheduled with an APP at discharge for stroke [3]. This clinic demonstrated the feasibility of an APP-led model of care transition for a high-risk condition with the potential for significant utilization and growth [3]. A similar APP-led transitions model in atrial fibrillation demonstrated not only feasibility but also improved adherence to American College of Cardiology/American Heart Association clinical performance and quality measures when patients were referred for specialty care compared with standard follow-up [4].
These patients were more likely to have screening for other relevant conditions and be prescribed anticoagulation appropriately [4].
Transitions of care in VTE by nonphysician providers have also been previously demonstrated by DiRenzo et al [5]. In this model, patients discharged from the ED were managed by an outpatient primary care physician or a pharmacist [5]. In this study, patients managed by pharmacists had similar safety outcomes when compared with primary care physician-managed follow-up [5].

| M E T H O D S
An APP-led acute VTE clinic, "VTE Transition Clinic," located within the Benign Hematology specialty clinic at the University of North Carolina (UNC) was established in January 2020 to provide transitions of care from outpatient or ED providers to hematology. Formal review of data did not begin until August 2020. The initial structure included 1 appointment reserved each weekday morning. For purposes of scheduling, this clinic has its own scheduling template without an assigned provider, and patients are later moved to the schedule of the treating provider. This allows free scheduling by referring locations without concerns about interference with other visits on an existing provider schedule.
The clinic was advertised to referring providers primarily through face-to-face interactions with the APP coordinator, who presented the clinical model as a guest at faculty and staff meetings throughout the UNC Health system. These meetings involved education on appropriate referrals and how to reach the clinic. Patients with newly diagnosed VTE can be referred by any UNC-affiliated provider. An algorithm was made available to the ED providers for determining appropriateness for outpatient management and referral. The eligibility criteria were modified from the Hestia criteria and applied to both deep vein thrombosis (DVT) and low-risk pulmonary embolism (PE) [6]. A triage system with direct pager and phone line ("1-DVT") is available during business hours. For patients referred after-hours through the ED, direct scheduling is available 24 hours a day through a patient access phone line more broadly utilized by UNC Health.
The hematology group includes 2 APPs who see classical (nonmalignant) hematology patients (including anemia and other disease groups outside of thrombosis) but reserve 1 slot each per day, in Essentials • There is a need for transitions of care in patients with newly diagnosed venous thromboembolism.
• An advanced practice provider-led clinic was designed to address this need at University of North Carolina Health.
• Utilization of the care transitions clinic grew over time, serving >200 patients in 2 years.
• The established model was feasible and evolved to serve increasingly diverse referral sources.

| R E S U L T S A N D D I S C U S S I O N
In the 2-year period since inception, a total of 234 patients were seen in the clinic. Of these, 84 were seen in the first year (August 24, 2020,  (Table). Hispanic patients represented 3.8% of the patients in year 1 and 9.3% of the patients in year 2, which was not a statistically significant change (Table).
Utilization steadily increased over the 2 years (Figure 1). In the first year, 72% of patients were referred from the ED (Figure 2) and 12.7% of all patients required financial assistance of some kind. In the second year, 59.3% of the referrals were from the ED ( Figure 2) and 10% of all patients required medication assistance. Medication assistance included providing a copay card, assisting with enrollment in pharmaceutical manufacturer assistance programs, enrollment in UNC-specific pharmacy assistance programs, or other assistance depending on patient need and circumstance.
Data on deviations in protocol were not collected in the first year, but in the second year, significant deviations from protocol were identified in 19 (12.7%) cases. These deviations included 8 circumstances in which anticoagulation was found to be unnecessary and was discontinued or a change had been made unnecessarily to previous anticoagulant therapy and the previous agent was resumed. In 4 cases, dosing errors were identified, and in 4 additional cases, the diagnosis was found to be misclassified. The remaining 3 were other deviations. The median time to appointment in the first year was 4 days, and in the second year, it was 5 days (including weekend days).
The APP has access to hematology physician providers in the clinic or by phone for consultation at all times. In the first year, an MD provider saw the patient in a shared visit, where the MD independently assessed the patient, only once. Due to the rare need for this, shared visit data were not collected in the second year.
The VTE Transition Clinic grew quickly in its first year and continued to grow in the second year, nearly doubling in utilization. In  the first year, the median time to visit was 4 days, and the program's aim was to decrease this. However, with increased utilization, this metric increased to 5 days. As a consequence, a second APP was hired to improve access. A second visit is now available daily in the afternoons to allow increased capacity and more rapid access to the clinic. trainees, changing referral pathways and dynamics in the healthcare system, and turnover of staff trained to schedule into the clinic.
In summary, since its inception, the APP-led VTE Transition Clinic has grown in utilization, diversity of referrals, and diversity of patients served, with new focus on patient education tools and expanding access.

FUNDING
The authors received no funding for this study.

AUTHOR CONTRIBUTIONS
All authors contributed to the design and development of the clinic. C.F. performed the implementation, data collection, and maintenance and analyzed all data, with contributions from S.W.. C.F. wrote the manuscript. All authors contributed to review of the manuscript.

S.M. has received honoraria from Bristol Myers Squibb and Stago
Diagnostics for consulting. C.F. has received payment for expert testimony from Angell Law Firm and honoraria from Pfizer for consulting and was an advisory panel member for cancer-associated thrombosis in 2021. The other authors have no competing interests to disclose.