Keenan, Megan

Background: The use of validated risk stratification tools for the workup of suspected pulmonary embolism (PE) is a recommendation of the American Society of Hematology and the American College of Emergency Physicians. Methods: We designed and implemented electronic clinical pretest probability (PTP) tools for use in emergency departments (ED). Overall, 38 EDs (tertiary and regional EDs) in the United States were involved across three health systems. PTP use was analyzed between September 12, 2022 and January 11, 2023 in 270,247 ED visits. PTP use was examined in terms of the percentage of visits for which patients underwent computed tomography pulmonary angiography (CTPA). Each site chose the 3-tier Wells’ score for implementation and Site 2 designed a combined Wells’, pulmonary embolism rule-out criteria (PERC), and YEARS score. Results: At Site 3, forced use resulted in documented PTP scores in 49–53% of ordered CTPAs. At Sites 1 and 2, where PTP scores were optional, documented PTP scores occurred in 2–3% and 1–3% of CTPA orders, respectively. At Site 1, the use of PTP increased slightly over the study period, with signs that PE yield on imaging was also increasing (3.4–5.9%). At Site 2, PE yield on imaging was 9–10%, and it remained similar, with similar use of PTP tools over the study period. PE yield (6–8%) on imaging also remained similar throughout the study at Site 3. Conclusions: Guideline-endorsed PTP scores for PE at three independent health systems in the United States did not increase PE yield on imaging. Novel implementation strategies involving interdisciplinary teams are urgently needed.

Guidelines for diagnosing pulmonary embolism (PE) start with a risk assessment using a pretest probability (PTP) tool, followed by D-dimer testing or computed tomography pulmonary angiography (CTPA) depending on risk. The project aimed to develop an electronic clinical quality measure (eCQM) to encourage broader use of a validated PTP scoring tool in emergency departments (EDs) to more accurately diagnose PE and to reduce unnecessary CTPAs. To identify a value set to accurately identify CTPA and abnormal D-dimer tests using standard classification systems and clinical vocabularies (ie, Current Procedural Terminology [CPT], Logical Observation Identifiers Names and Codes [LOINC], systematized nomenclature of medicine clinical terms [SNOMED CT]) across 3 academic United States health care systems. A comprehensive value set to identify CTPAs was selected, which contained 31 codes. Additionally, each health care system had unique, site-specific codes to more granularly identify CTPAs. Three health care systems representing 38 EDs from across the country submitted data from all ED encounters between September 12, 2022, and January 11, 2023. Imaging types were reviewed from each of the CPT codes and LOINC. The project evaluated whether a D-dimer was obtained using CPT and LOINC and whether the D-dimer result was elevated using SNOMED CT. The number of ED encounters, PTP use, and diagnosis of PE using different codes were determined. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value for selected codes were calculated. Over a 4-month study period, 270,214 encounters were included from 38 EDs. 11,794 ED encounters with CTPAs during the study period, using the site-specific codes were identified. The comprehensive value set had a PPV of 63.4%. Restricting the CTPA value set to CPT code 71275 or LOINC 88322-3 improved the PPV to 82% with 100% sensitivity and 99% specificity. The restricted value set captured the highest proportion of relevant site-specific codes. D-dimer values were identified using LOINC codes 48065-7 and 91556-1 at Site 1 and 48067-3 at Site 2. SNOMED CT codes were not used at any site to identify elevated D-dimer results. Different D-dimer tests with different normal ranges were used at each site, and only one site provided an abnormal flag for D-dimer results. Heterogeneity in the use of nationally standardized codes for labs and imaging tests limits the ability to measure and compare quality across health care organizations for CTPA and D-dimer results. Restricting the identification of CTPA to CPT Code 71275 or LOINC 88322-3 resulted in high sensitivity and specificity, but false positives remain. Additionally, coding for an abnormal D-dimer test result is not standardized across institutions. Therefore, the currently available value sets cannot be used to develop eCQMs whose aim is to evaluate whether CTPA is ordered appropriately based on the PTP risk level and laboratory testing.

Introduction: Use of validated risk stratification tools for work up of suspected pulmonary embolism (PE) is an endorsed recommendation of the American Society of Hematology and the American College of Emergency Physicians. Due to variations in clinical practice, electronic health record (EHR) systems, and medical provider trainings, the use, documentation, and implementation of these tools vary widely. Current processes do not allow for electronic capture and quality reporting at most institutions. Methods: We sought to design and implement clinical pre-test probability (PTP) tools at three large healthcare institutions for use in emergency departments (ED). At each site, a hematologist partnered with ED physician leadership and local information technology experts to design and implement PTP tools in clinical workflows. Overall, 38 EDs (high volume tertiary EDs and smaller regional EDs) located in the United States along the East Coast and Midwest regions were involved. A major goal of implementation was integration into clinical workflow and automatic documentation. After design and implementation, awareness and education of the new EHR tool was distributed electronically to ED providers. After implementation, use of PTP tools was analyzed between September 12, 2022 and January 11, 2023. PTP use was examined as percent of visits for which patients underwent CT pulmonary angiography (CTPA). Results: Each institution chose the 3 tier Wells' Score for implementation while one site designed an integrated Wells'/PERC or YEARS score calculator. Two sites implemented the tool as an optional flowsheet and one site implemented the tool as mandatory parameters within the orders for PE imaging studies. The mandatory tool could be bypassed with prespecified selections or if a D-dimer existed within 48 hours . Complete details of the site-specific implementation are shown in Table 1. Over the 4-month evaluation timeframe, there was a total of 270,214 ED encounters. Uptake and utilization of the PTP tools are shown in Table 2. Use of PTP was highest at the site with forced PTP documentation which ranged from 49-53% of ordered CTPAs, compared to Site 2 where use was 2-3%, and Site 1 where use ranged from 1-3%. At Site 1, use of PTP increased slightly over the study period with signs that PE yield on imaging was increasing as well (3.4% to 5.9%). At Site 2, PE yield on imaging was overall high (9-10%), and remained similar with similar use of PTP tools over the study period. Use of PTP and PE yield (6-8%) on imaging also remained similar throughout the study at Site 3. Conclusion: Forced use of PTP within the orders for CTPA led to the highest use of PTP (Site 3) but this did not result in meaningfully higher PE yield on CTPA compared to the other sites. PE yield at each site was at or above the 5% yield for PE on CTPA which has been previously reported. Given that PTP uptake was relatively stable over the measurement period at Site 2 and 3, this indicates the process had mostly stabilized and that other strategies are needed to improve uptake of PTP, reduce utilization of CTPA, and further increase yield on CTPA. Increasing PTP use and rising PE yield at Site 1 demonstrated ongoing potential for improvements past this study timeframe.

Introduction: ASH Guidelines for diagnosis of pulmonary embolism (PE) start with risk assessment using a pretest probability tool (PTP) followed by D-dimer testing or CT pulmonary angiography (CTPA) depending on risk. We aimed to develop an electronic clinical quality measure (eCQM) to encourage broader use of a validated PTP scoring tool in emergency departments (EDs). The Centers for Medicare & Medicaid Services require reporting of eCQMs which consist of value sets or lists of standardized codes linked to patient data within the electronic health record. We sought to identify a standardized way to identify CTPA and abnormal D-dimer tests using administrative codes (i.e. CPT, LOINC, SNOMEDCT codes) across three institutions. Methods: Value sets identifying CTPA and D-dimers were reviewed from existing eCQMs. Three institutions representing 38 EDs from across the country submitted data from all ED encounters between September 12, 2022 and January 11, 2023. Imaging types were reviewed from each of the CPT codes and LOINC (Logical Observation Identifiers Names and Codes). We determined the number of ED encounters, pre-test probability tool use, and diagnosis of PE using different codes. We calculated sensitivity, specificity, positive and negative predictive value (PPV and NPV, respectively). Results: Over the 4-month study period, 270,214 encounters were identified across 38 EDs. Each institution identified CTPA with site-specific codes (Table 1). The Full CTPA Value Set identified 55% more encounters than the site-specific codes (Full set 15,054/9679 site-specific codes). LOINC code 88322-3 was only used at one site. CPT code 71275 had the best sensitivity and specificity, but still had false positives (PPV 82%) (Table 2). D-dimer values were identified as LOINC code 48065-7 and 91556-1 at Site 1 and 48067-3 at Site 2. SNOMEDCT codes were not used at any site despite being the way other eCQMs identify elevated D-dimer results. Different D-dimer tests with different normal ranges were used at each site. All sites did not have an electronically extractable positive indicator for D-dimer. Conclusion: Due to persistent false positives using CPT Code 71275 for identification of CTPA, using this code would lead to inclusion of patients for whom PTP was not required or recommended. Additionally, coding for an abnormal D-dimer test result are not standardized across institutions. Therefore, administrative codes cannot be used to develop eCQMs whose aim is to evaluate whether CTPA is ordered appropriately based on the PTP risk level and laboratory testing.

Introduction Pulmonary Embolism (PE) is a major cause of morbidity and mortality worldwide. Diagnosis is essential as untreated PE has a 30% mortality rate. Currently, computer tomography pulmonary angiogram (CTPA) is the standard of care to diagnose PE. However, this modality is expensive, exposes patients to radiation and increases risk of contrast induced nephropathy. Furthermore, only 5% of CTPAs performed are positive for PE signifying that many unnecessary tests are being performed. To address this gap, Pre-Test Probability (PTP) tools have been developed to safely exclude patients with low risk of PE and limit iatrogenic harm from over testing. Despite the tools being developed over 20 years ago, they are not widely available in electronic health record (EHR) systems and even when they are built in, uptake remains low. Methods Three large integrated health systems using Epic EHR systems across five states (MA, WI. MN, AZ, FL) built electronic PTP assessments into their EHR systems to safely exclude patients with low risk of PE and limit over testing. Two sites made the PTP optional, and one site made it a forced function (providers were forced to complete PTP prior to ordering CTPA unless a D-dimer result was present in the prior 48 hours). To assess the usability of these EHR tools, the team conducted a survey with ED clinicians across the three test sites. The survey was created to identify which PE risk stratification methods were employed by ED clinicians (EHR embedded PTP tool, apps on their phone, web applications like MDcalc, calculations from memory, or if they relied on clinical gestalt), and to identify barriers to using the EHR embedded PTP. Results Site 1 had 47 respondents, Site 2 had 94 respondents, and Site 3 had 16 respondents. Two key findings emerged from the survey (Figure 1). First, clinicians used a variety of risk stratification approaches and few of them documented their risk assessments in structured fields in the medical record. Second, clinical gestalt was the most used PE risk stratification approach, and this was true across all three test sites. In addition, the health system with a PTP prompt before clinicians could proceed with CTPA orders (Site 3) did not have a higher percentage of clinicians who reported using the EHR embedded tool than sites that did not prompt clinicians to fill in the PTP. Clinicians cited a variety of different barriers to using the EHR embedded PTP tool (Table 1). Conclusion While many clinicians indicated intermittent use of PTP criteria to aid in the diagnosis of PE, risk factors and scores from phone apps, web tools, and calculations from memory are unlikely to be documented in the patient's medical record, which means that they are not accessible to all members of the ED care team and cannot be used for electronic clinical quality measure. The biggest hurdles to increasing the use of structured PTP assessments in the ED setting to safely exclude PE and limit iatrogenic harm from over testing are (1) obtaining buy-in from ED clinicians that the PTP tools provide value over clinical gestalt, at least for a subset of patients who could most benefit, and (2) identifying best practices for incorporating PTP tools into EHR systems that make the tools easier to access and use 3) developing and implementing effective education and awareness programs around the PTP tools. This survey adds to the body of literature on PTP assessments in the ED setting and can help inform further research that is needed to continue to improve the diagnosis of PE. Funding: This project is funded in part by the Gordon and Betty Moore Foundation through Grant GBMF10778 to the American Society of Hematology.