Clinical Policy: Critical Issues in the Evaluation and Management of Adult Patients With Suspected Acute Nontraumatic Thoracic Aortic Dissection

The sonographic protocol for the emergent evaluation of aortic dissections (SPEED protocol): A multicenter, prospective, observational study

OBJECTIVES

An aortic dissection (AoD) is a potentially life-threatening emergency with mortality rates exceeding 50%. While computed tomography angiography remains the diagnostic standard, patients may be too unstable to leave the emergency department. Investigators developed a point-of-care ultrasound (POCUS) protocol combining transthoracic echocardiography (TTE) and the abdominal aorta. The study objective was to determine the test characteristics of this protocol.

METHODS

This was an institutional review board-approved, multicenter, prospective, observational, cohort study of a convenience sample of adult patients. Patients suspected of having an AoD received a TTE and abdominal aorta POCUS. Three sonographic signs suggested AoD: a pericardial effusion, an intimal flap, or an aortic outflow track diameter measuring more than 35 mm. Investigators present continuous and categorical data as medians with interquartile ranges or proportions with 95% confidence intervals (CIs) and utilized standard 2 × 2 tables on MedCalc (Version 19.1.6) to calculate test characteristics with 95% CI.

RESULTS

Investigators performed 1314 POCUS examinations, diagnosing 21 Stanford type A and 23 Stanford type B AoD. Forty-one of the 44 cases had at least one of the aforementioned sonographic findings. The protocol has a sensitivity of 93.2% (95% CI 81.3-98.6), specificity of 90.9 (95% CI 89.2-92.5), positive and negative predictive values of 26.3% (95% CI 19.6-33.9) and 99.7% (95% CI 99.2-100), respectively, and an accuracy of 91% (95% CI 89.3-92.5).

CONCLUSIONS

The SPEED protocol has an overall sensitivity of 93.2% for AoD.

2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Management of hypertensive crisis: British and Irish Hypertension Society Position document

Patients with hypertensive emergencies, malignant hypertension and acute severe hypertension are managed heterogeneously in clinical practice. Initiating anti-hypertensive therapy and setting BP goal in acute settings requires important considerations which differ slightly across various diagnoses and clinical contexts. This position paper by British and Irish Hypertension Society, aims to provide clinicians a framework for diagnosing, evaluating, and managing patients with hypertensive crisis, based on the critical appraisal of available evidence and expert opinion.

Twenty-five years of observations from the International Registry of Acute Aortic Dissection (IRAD) and its impact on the cardiovascular scientific community

OBJECTIVE

The International Registry of Acute Aortic Dissection (IRAD) celebrated its 25th anniversary in January 2021. This study evaluated IRAD's role in promoting the understanding and management of acute aortic dissection (AD) over these years.

METHODS

IRAD studies were identified, analyzed, and ranked according to their citations per year (c/y) to determine the most-cited IRAD studies and topics. A systematic search of the literature identified cardiovascular guidelines on the diagnosis and management of acute AD. Consequently, IRAD's presence and impact were quantified using these documents.

RESULTS

Ninety-seven IRAD studies were identified, of which 82 obtained more than 10 cumulative citations. The median c/y index was 7.33 (25th-75th percentile, 4.01-16.65). Forty-two studies had a greater than median c/y index and were considered most impactful. Of these studies, most investigated both type A and type B AD (n = 17, 40.5%) and short-term outcomes (n = 26, 61.9%). Nineteen guideline documents were identified from 26 cardiovascular societies located in Northern America, Europe, and Japan. Sixty-nine IRAD studies were cited by these guidelines, including 38 of the 42 most-impactful IRAD studies. Among them, partial thrombosis of the false lumen as a predictor of postdischarge mortality and aortic diameters as a predictor of type A occurrence were determined as most-impactful specific IRAD topics by their c/y index.

CONCLUSIONS

IRAD has had and continues to have an important role in providing observations, credible knowledge, and research questions to improve the outcomes of patients with acute AD.

ACR Appropriateness Criteria® Thoracoabdominal Aortic Aneurysm or Dissection: Treatment Planning and Follow-Up

As the incidence of thoracoabdominal aortic pathology (aneurysm and dissection) rises and the complexity of endovascular and surgical treatment options increases, imaging follow-up of patients remains crucial. Patients with thoracoabdominal aortic pathology without intervention should be monitored carefully for changes in aortic size or morphology that could portend rupture or other complication. Patients who are post endovascular or open surgical aortic repair should undergo follow-up imaging to evaluate for complications, endoleak, or recurrent pathology. Considering the quality of diagnostic data, CT angiography and MR angiography are the preferred imaging modalities for follow-up of thoracoabdominal aortic pathology for most patients. The extent of thoracoabdominal aortic pathology and its potential complications involve multiple regions of the body requiring imaging of the chest, abdomen, and pelvis in most patients. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Development and validation of nomogram models to discriminate between acute aortic syndromes and non-ST-elevation myocardial infarction during troponin-blind period

Background

Blood-test-based methods of distinguishing between acute aortic syndromes (AASs) and non-ST-elevation myocardial infarction (NSTEMI) during the troponin-blind period of <2-3 h of symptom onset have not been studied previously. We aimed to explore whether routine biomarkers might facilitate differential diagnosis.

Methods

Data were retrospectively collected from 178 patients with AASs and 460 patients with NSTEMI within 3 h of onset. Differential risk factors related to AASs were identified by univariate and multivariate logistic regression analyses for patients with onset <2 h and onset ≥2 h, respectively, in the cardiac troponin (cTn) cohort. Nomograms were established in the cTn cohort as a training set and validated in the high-sensitivity cTn cohort. To assess the utility of the models in clinical practice, decision curve analyses were performed.

Results

D-dimer, fibrinogen, and age were identified as differential risk factors for AASs with the onset of <2 h. D-dimer at an optimal cutoff level of 281 ng/mL for AASs had a sensitivity of 86.4% and a specificity of 91.3%. A nomogram was developed and validated with areas under the curve (AUC) of 0.934 (95% CI: 0.880-0.988) and 0.952 (95% CI: 0.874-1.000), respectively. D-dimer, neutrophil, bilirubin, and platelet were the differential risk factors for AASs with the onset of ≥2 h. D-dimer at an optimal cutoff level of 385 ng/mL has a sensitivity of 91.8% and a specificity of 91.3%. The AUC of the second nomogram in the training set and the validation set were 0.965 (95% CI: 0.942-0.988) and 0.974 (95% CI: 0.944-1.000), respectively.

Conclusion

Time-dependent quality of D-dimer should be considered for discriminating AASs from NSTEMI. Both nomogram models may have a clinical utility for evaluating the probability of AASs.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate. Structure: Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Fentanyl versus placebo with ketamine and rocuronium for patients undergoing rapid sequence intubation in the emergency department: The FAKT study-A randomized clinical trial

Objective

The objective was to determine whether the use of fentanyl with ketamine for emergency department (ED) rapid sequence intubation (RSI) results in fewer patients with systolic blood pressure (SBP) measurements outside the pre‐specified target range of 100–150 mm Hg following the induction of anesthesia.

Methods

This study was conducted in the ED of five Australian hospitals. A total of 290 participants were randomized to receive either fentanyl or 0.9% saline (placebo) in combination with ketamine and rocuronium, according to a weight‐based dosing schedule. The primary outcome was the proportion of patients in each group with at least one SBP measurement outside the prespecified range of 100–150 mm Hg (with adjustment for baseline abnormality). Secondary outcomes included first‐pass intubation success, hypotension, hypertension and hypoxia, mortality, and ventilator‐free days 30 days following enrollment.

Results

A total of 142 in the fentanyl group and 148 in the placebo group commenced the protocol. A total of 66% of patients receiving fentanyl and 65% of patients receiving placebo met the primary outcome (difference = 1%, 95% CI = −10 to 12). Hypotension (SBP ≤ 99 mm Hg) was more common with fentanyl (29% vs. 16%; difference = 13%, 95% CI = 3% to 23%), while hypertension (≥150 mm Hg) occurred more with placebo (69% vs. 55%; difference = 14%, 95% CI = 3 to 24). First‐pass success rate, 30 day mortality, and ventilator‐free days were similar.

Conclusions and Relevance

There was no difference in the primary outcome between groups, although lower blood pressures were more common with fentanyl. Clinicians should consider baseline hemodynamics and postinduction targets when deciding whether to use fentanyl as a coinduction agent with ketamine.

Acute Aortic Syndrome Revisited: JACC State-of-the-Art Review

The purpose of this paper is to describe all available evidence on the distinctive features of a group of 4 life-threatening acute aortic pathologies gathered under the name of acute aortic syndrome (AAS). The epidemiology, diagnostic strategy, and management of these patients has been updated. The authors propose a new and simple diagnostic algorithm to support clinical decision making in cases of suspected AAS, thereby minimizing diagnostic delays, misdiagnoses, and unnecessary advanced imaging. AAS-related entities are reviewed, and a guideline to avoid imaging misinterpretation is provided. Centralization of patients with AAS in high-volume centers with high-volume surgeons is key to improving clinical outcomes. Thus, the role of multidisciplinary teams, an "aorta code" (streamlined emergent care pathway), and aortic centers in the management of these patients is boosted. A tailored patient treatment approach for each of these acute aortic entities is needed, and as such has been summarized. Finally, a set of prevention measures against AAS is discussed.

Can D-Dimer in Low-Risk Patients Exclude Aortic Dissection in the Emergency Department?

BACKGROUND

Aortic dissection (AD) is a challenging diagnosis associated with severe mortality. However, acute AD is a rare clinical entity and can be overevaluated in the emergency department. D-dimer, both alone and in combination with the Aortic Dissection Detection Risk Score (ADD-RS), has been studied as a tool to evaluate for AD.

CLINICAL QUESTION

Can a negative D-dimer in low-risk patients exclude AD in the emergency department?

EVIDENCE REVIEW

Retrieved studies included three systematic review and meta-analyses and two prospective cohort studies. D-dimer was found to be highly sensitive for acute AD, with a sensitivity of 98.0%. The ADD-RS was also highly sensitive (95.7%) for AD. Two meta-analyses reported a combination of a negative D-dimer and ADD-RS < 1 to have a pooled sensitivity of 99.9% and 100% for acute aortic syndrome.

CONCLUSIONS

Neither D-dimer nor the ADD-RS alone provides adequate sensitivity to exclude acute AD. However, a negative D-dimer combined with an ADD-RS < 1 is likely sufficient to rule out AD. Even with these findings, physicians must place clinical judgment above laboratory testing or scoring systems when deciding whether to pursue a diagnosis of acute AD.

Does implementation of a diagnostic pathway for acute aortic syndrome including D-dimer increase the usage of D-dimer and computed tomography?

INTRODUCTION

The Canadian clinical practice guidelines propose a novel diagnostic pathway incorporating a clinical decision tool and D-dimer to aid in risk stratifying patients for acute aortic syndrome. The objective of this study was to assess if implementation of a diagnostic pathway incorporating D-dimer would increase the usage of D-dimer and computed tomography (CT) in a tertiary care emergency department.

METHODS

Prospective single centre before and after study-recruiting patients over a 6-week period from a tertiary care emergency department.

INTERVENTION

multi model implementation of a diagnostic pathway for acute aortic syndrome incorporating D-dimer.

OUTCOME

proportion of patients receiving D-dimer testing/CT in the 2 weeks before and after implementation.

RESULTS

We included 982 patients (Female 55%, Age mean 51.9, N = 492 pre intervention and N = 490 post intervention). The proportion that received a D-dimer test increased from 6.9 to 10.4% (p < 0.051), while the number of CT aortas remained stable (0.6% vs. 0.6%; p = 0.60). Documentation of pretest probability assessment increased from 1 to 3%, (p < 0.009) following the intervention. In the post intervention cohort, the tool was applied correctly in all cases (N = 17).

CONCLUSION

This single centre study found that a diagnostic pathway for acute aortic syndrome including D-dimer could be implemented without a significant increase in test ordering during this first 2 weeks after implementation. This study adds to the argument for use of D-dimer to help risk stratify patients for the diagnosis of acute aortic syndrome. Future studies are needed to confirm the diagnostic accuracy of this pathway and the long-term impact on resource utilization.

Indirect signs of aortic dissection on POC-TTE despite an ADD-RS of 0 and D-dimer < 500 ng/mL: A case report

Aortic dissection (AD) is a "can't miss" diagnosis for emergency physicians. An algorithm combining the Aortic Dissection Detection Risk Score (ADD-RS) with D-dimer has been proposed as a high-sensitivity clinical decision tool for AD that can determine the need for advanced imaging. Here we present a case of a 48-year-old male who presented to the emergency department (ED) with chest pain and dyspnea. He had an ADD-RS score of 0 and negative D-dimer, which placed him in the low-risk category not requiring further advanced imaging. Despite this, he was found to have a pericardial effusion and dilated aortic root on point-of-care transthoracic echocardiogram (POC-TTE). These findings increased suspicion for AD and prompted the emergency physician to order a computed tomography angiography (CTA), revealing a thoracic AD. The patient successfully underwent surgical repair. This case demonstrates that the ADD-RS + D-dimer algorithm would have erroneously ruled out AD, without the inclusion of indirect findings of AD from the POC-TTE. This highlights the value of using POC-TTE as an adjunct to the ADD-RS + D-dimer algorithm in the diagnostic evaluation of AD and how giving more weight to indirect signs of AD on POC-TTE could potentially increase the sensitivity of the combined ADD-RS + D-dimer + POC-TTE algorithm.

Nomogram to differentiate between aortic dissection and non-ST segment elevation acute coronary syndrome: a retrospective cohort study

Background

Aortic dissection (AD) and non-ST segment elevation acute coronary syndrome (ACS) are two of the most life-threatening diseases encountered in the emergency department (ED), but there are no rapid and reliable tools for differentiation. The purpose of this study is to develop and validate a nomogram that incorporates both the clinical characteristics and bedside laboratory tests available to differentiate between AD and non-ST segment elevation ACS (NSTE-ACS).

Methods

Between January 2016 and July 2018, patients with AD and NSTE-ACS were enrolled and divided into training and validation groups. The least absolute shrinkage and selection operator (LASSO) regression model was used to select the factors with significant value of predicting the diagnosis of AD. A nomogram was built on the basis of multivariable logistic regression analysis. Area under the curve (AUC) of receiver operating characteristic (ROC) curve and the calibration curve were used to assess the performance of the nomogram. Decision curve analysis was performed to assess the clinical utility of the nomogram.

Results

A final cohort of 263 patients (94 patients with AD and 169 patients with NSTE-ACS) were enrolled. Six variables were incorporated in the nomogram: pain severity, tearing pain, pulse asymmetry, electrocardiogram (ECG), D-dimer level and troponin I level. The AUC of the nomogram to predict the probability of AD was 0.919 (95% CI, 0.876-0.962) in the training group and 0.938 (95% CI, 0.888-0.989) in the validation group. The calibration curve demonstrated a good consistency between the actual clinical results and the predicted outcomes. The decision curve analysis indicated that the nomogram had higher overall net benefits in predicting AD in both the training group and the validation group.

Conclusions

We developed and validated a predictive nomogram that could be used as a tool to differentiate AD from NSTE-ACS rapidly and accurately.

Systematic Review of Aortic Dissection Detection Risk Score Plus D-dimer for Diagnostic Rule-out Of Suspected Acute Aortic Syndromes

OBJECTIVES

In patients at low clinical probability of acute aortic syndromes (AASs), decision on advanced aortic imaging is cumbersome. Integration of the aortic dissection detection risk score (ADD-RS) with D-dimer (DD) provides a potential pipeline for standardized diagnostic rule-out. We systematically reviewed and summarized supporting data.

METHODS

Cross-sectional studies assessing integration of ADD-RS with DD for diagnosis of AASs were identified on MEDLINE, EMBASE and Web Of Science databases. Two reviewers independently screened articles, assessed quality, and extracted data. The quality of design and reporting was evaluated with the QUADAS-2 and STARD tools. Individual patient data were obtained, to allow analysis of both conventional (500 ng/mL) and age-adjusted (DD_age-adj ) DD cutoffs. Data were summarized for four diagnostic strategies combining ADD-RS = 0 or ≤ 1, with DD < 500 ng/mL or < DD_age-adj . The statistical heterogeneity of the diagnostic variables was estimated with Higgins' I² . Pooled values were calculated for variables showing nonsignificant heterogeneity.

RESULTS

After screening of 680 studies, four articles (including a total of 3,804 patients) met inclusion criteria. One prospective study provided a low risk of bias/applicability concerns, while methodologic limitations were found in the other three retrospective studies. Statistical heterogeneity was negligible for sensitivity and negative likelihood ratio (LR) values and significant for specificity and positive LR values of all diagnostic strategies. Pooled sensitivity was 99.9% (95% confidence interval [CI] = 99.3% to 100%, I²  = 0) for ADD-RS = 0 and DD < 500 ng/mL or < DD_age-adj , 98.9% (95% CI = 97.9% to 99.9%, I²  = 0) for ADD-RS ≤ 1 and DD < 500 ng/mL, and 97.6% (95% CI = 96.3% to 98.9%, I²  = 0) for ADD-RS ≤ 1 and DD < DD_age-adj .

CONCLUSIONS

Despite methodologic limitations, integration of ADD-RS = 0 or ≤ 1 with DD < 500 ng/mL shows negligible heterogeneity and consistently high sensitivity across studies, thus supporting reliability for diagnostic rule-out of AASs. Data supporting ADD-RS = 0 plus DD_age-adj appear preliminary and require further scrutiny.

Implementation of an aortic dissection CT protocol with clinical decision support aimed at decreasing radiation exposure by reducing routine abdominopelvic imaging

Patients suspected of having an acute aortic syndrome in the ED typically undergo CT of the chest/abdomen/pelvis. However, the overwhelming majority of these exams are negative. With the help of clinical decision support, we implemented a new radiologist monitored 'aortic dissection screening protocol' that forgoes routine abdominopelvic imaging in order to reduce radiation dose without compromising diagnostic accuracy. The purpose of the present study is to assess the performance of this protocol. A retrospective analysis was performed to study the effect of the dissection screening protocol on the diagnostic yield, radiation and contrast dose on a total of 835 ED patients who underwent CT scans for suspected aortic dissection over a 48-week study period immediately before and after implementation of the protocol. 3.4% (28/835) of examinations were positive for an acute aortic syndrome over the 48-week study period with no difference in positivity before and after implementation of the 'aortic dissection screening' protocol, 3.0% vs. 3.7%, respectively (p = 0.57). There was a 14.6% reduction in median radiation dose and a 16% decrease in contrast volume utilization for the total ED population who underwent CT for aortic dissection using any protocol in the period after implementation of the 'aortic dissection screening' protocol. Aortic dissection CT in the ED is negative in the overwhelming majority of cases. A monitored 'aortic dissection screening' protocol that initially images the chest only significantly reduced contrast and radiation dose without reducing diagnostic accuracy for ED patients who underwent CT for aortic dissection.

High-Risk Chief Complaints I: Chest Pain-The Big Three (an Update)

Nontraumatic chest pain is a frequent concern of emergency department patients, with causes that range from benign to immediately life threatening. Identifying those patients who require immediate/urgent intervention remains challenging and is a high-risk area for emergency medicine physicians where incorrect or delayed diagnosis may lead to significant morbidity and mortality. This article focuses on the 3 most prevalent diagnoses associated with adverse outcomes in patients presenting with nontraumatic chest pain, acute coronary syndrome, thoracic aortic dissection, and pulmonary embolism. Important aspects of clinical evaluation, diagnostic testing, treatment, and disposition and other less common causes of lethal chest pain are also discussed.

The risk of misdiagnosis in acute thoracic aortic dissection: a review of current guidelines

Acute aortic syndrome and in particular aortic dissection (AAD) persists as a cause of significant morbidity and mortality despite improvements in surgical management. This clinical review aims to explore the risks of misdiagnosis, outcomes associated with misdiagnosis and evaluate current diagnostic methods for reducing its incidence.Due to the nature of the pathology, misdiagnosing the condition and delaying management can dramatically worsen patient outcomes. Several diagnostic challenges exist, including low prevalence, rapidly propagating pathology, non-discrete symptomatology, non-specific signs, analogy with other acute conditions and lack of management infrastructure. A similarity to acute coronary syndromes is a specific concern and risks patient maltreatment. AAD with malperfusion syndromes are both a cause of misdiagnosis and marker of disease complication, requiring specifically tailored management plans from the emergency setting.Despite improvements in diagnostic measures, including imaging modalities and biomarkers, misdiagnosis of AAD remains commonplace and current guidelines are relatively limited in preventing its occurrence. This paper recommends the early use of AAD risk scoring, focused echocardiography and most importantly, fast-tracking patients to cross-sectional imaging where the suspicion of AAD is high. This has the potential to improve the diagnostic process for AAD and limit the risk of misdiagnosis. However, our understanding remains limited by the lack of large patient datasets and an adequately audited processes of emergency department practice.

Accuracy of aortic dissection detection risk score alone or with D-dimer: A systematic review and meta-analysis

BACKGROUND

To evaluate the diagnostic accuracy and clinical utility of the acute aortic dissection detection risk score (ADD-RS) alone or with D-dimer as a screening test to exclude acute aortic syndrome.

METHODS

We conducted a systematic review and meta-analysis of studies examining the diagnostic accuracy of ADD-RS. We searched MEDLINE, Embase and Cochrane Controlled Register of Trials up to 12 December 2018.

RESULTS

We identified nine studies involving 26,598 patients for ADD-RS alone and 3421 patients with D-dimer. Overall, the methodological quality based on the Quality Assessment of Diagnostic Accuracy Studies 2 was moderate to high. Bivariate meta-analyses showed that the pooled sensitivities were 0.94 (95% confidence interval (CI) 0.90, 0.96) at the threshold of ADD-RS ≥1, 0.46 (95% CI, 0.34, 0.59) at ADD-RS ≥2, 1.00 (95% CI 0.99, 1.00) at ADD-RS ≥1 with D-dimer and 0.99 (95% CI 0.97, 1.00) at ADD-RS ≥2 with D-dimer. For the low prevalence population, failure rate and efficiency were 0.8% and 38.3% at ADD-RS ≥1, 0.03% and 14.5% at ADD-RS ≥1 with D-dimer, and 0.1% and 33.6% at ADD-RS ≥2 with D-dimer, respectively. For the high prevalence population, failure rate and efficiency were 3.8% and 33.3% at ADD-RS ≥1, 0.2% and 12.3% at ADD-RS ≥1 with D-dimer and 0.6% and 28.4% at ADD-RS ≥2 with D-dimer, respectively.

CONCLUSIONS

ADD-RS alone or with D-dimer was a useful screening test with high sensitivity to exclude acute aortic syndrome. However, the optimal threshold of ADD-RS alone or with D-dimer may depend on the clinical setting.

Chest pain while gardening: a Stanford type A dissection involving the aortic root extending into the iliac arteries—an uncommon and potentially catastrophic disease process

Background

An aortic dissection is an uncommon and potentially catastrophic disease process that carries with it a high morbidity and mortality. The inciting event is a tear in the intimal lining of the aorta. This allows passage of blood through the tear and into the aortic media, resulting in the creation of a false lumen.

Case presentation

We describe the case of a 71-year-old male with a history of hypertension that suffered a Stanford type A dissection with an intimal flap beginning at the level of the aortic root and extending into the bilateral iliac arteries. His clinical presentation was further complicated by shock, cardiac tamponade, severe coagulopathy, an ischemic right lower extremity, infarction of his thoracic spinal cord, and subacute infarcts secondary to malperfusion and embolic disease. Despite maximal intervention, the patient continued to clinically decline and ultimately died on day 5.

Conclusion

The clinical presentation of an acute aortic dissection is often atypical and mimics other common disease processes. The signs and symptoms largely depend on the extent of the aortic dissection and the presence or absence of malperfusion. With a mortality increasing by 1–2% for every hour until definitive treatment, early recognition and prompt operative intervention are crucial for patient survival.

Importance of Multiple-window Assessment for the Diagnosis of Ascending Aortic Dissection Using Point-of-care Ultrasound: Report of Three Cases

Acute ascending aortic dissection has a high mortality rate and requires rapid diagnosis and treatment. Point-of-care ultrasound (POCUS) can aid in the diagnosis. The aortic root is usually evaluated in the parasternal long-axis view; however, a dissection flap is not always visible in this projection. We present three cases of acute, type A aortic dissection in which the dissection flap was only evident in the apical five-chamber and subxyphoid views. These cases suggest that POCUS may play a pivotal role in the initial diagnosis of acute ascending aortic dissection and highlight the importance of viewing multiple windows to fully evaluate this possibility.

Nursing patients with acute aortic dissection in emergency departments

Acute aortic dissection is an emergency condition that is often missed during initial assessment. Delay in diagnosis increases mortality, but the presentation can mimic several more common conditions. Emergency practitioners must maintain a high index of suspicion in patients who present with chest or back pain and ensure timely diagnostic testing and interpretation of results if aortic dissection is suspected.

Pleuritic chest pain and fever: An unusual presentation of aortic dissection

It remains a challenge to diagnose aortic dissection in primary care, as classic clinical features are not always present. This case describes an atypical presentation of aortic dissection, in which the patient walked in with pleuritic central chest pain associated with a fever and elevated C-reactive protein. Classic features of tearing pain, pulse differentials, and a widened mediastinum on chest X-ray were absent. This unusual presentation highlights the need for a heightened level of clinical suspicion for aortic dissection in the absence of classic features. The case is discussed with reference to the literature on the sensitivity and specificity of the classic signs and symptoms of aortic dissection. A combination of the aortic dissection detection risk score (ADD-RS) and D-dimer test is helpful in ruling out this frequently lethal condition.

Engaging patients and caregivers in establishing research priorities for aortic dissection

Objectives:

The aim of this study was to establish the top 10 research uncertainties in aortic dissection together with the patient organization Aortic Dissection Association Scandinavia using the James Lind Alliance concept.

Methods:

A pilot survey aiming to identify uncertainties sent to 12 patients was found to have high content validity (scale content validity index = 0.91). An online version of the survey was thereafter sent to 30 patients in Aortic Dissection Association Scandinavia and 45 caregivers in the field of aortic dissection. Research uncertainties of aortic dissection were gathered, collated and processed.

Results:

Together with research priorities retrieved from five different current guidelines, 94 uncertainties were expressed. A shortlist of 24 uncertainties remained after processing for the final workshop. After the priority-setting process, using facilitated group format technique, the ranked final top 10 research uncertainties included diagnostic tests for aortic dissection; patient information and care continuity; quality of life; endovascular and medical treatment; surgical complications; rehabilitation; psychological consequences; self-care; and how to improve prognosis.

Conclusion:

These ranked top 10 important research priorities may be used to justify specific research in aortic dissection and to inform healthcare research funding decisions.

Point-of-care Ultrasound Diagnosis of an Atypical Acute Aortic Dissection

Aortic dissections have a vast array of clinical presentations that rarely follow traditional teachings. Dissections are rapidly fatal conditions requiring immediate diagnosis and treatment to reduce morbidity and mortality. We present a case of an acute aortic dissection presenting as abrupt onset, atraumatic leg pain with absent distal extremity pulses. The prompt use of point-of-care ultrasound detected an intimal flap within the abdominal aorta allowing immediate surgical consultation and intervention.

Variation in emergency department use of computed tomography for investigation of acute aortic dissection

INTRODUCTION

Acute aortic dissection (AAD) is a life-threatening condition making early diagnosis critical. Although 90% present with acute pain, the myriad of associated symptoms can make diagnosis a challenge. Our objective was to assess how we are using computed tomography to rule out acute aortic dissection specifically rate of ordering, diagnostic yield, and variation in practice.

METHODS

We included consecutive adult patients presenting to two tertiary academic care emergency departments over one calendar year presenting with non-traumatic chest, back, abdominal, or flank pain. Primary outcome was rate of CT thorax/abdomen ordered to rule out AAD. Secondary outcome was variation in CT ordering, measured comparing number of CTs ordered per physician. Sample size of 12 per group was calculated based on an expected delta in mean CT ordered of 5 and a within group SD of 3.

RESULTS

Thirty-one thousand two hundred one patients presented with truncal pain during the study period, 22,729 were included (mean 47 years, SD 18.5 years, 56.2% female); prevalence of AAD (N = 4) was 0.02%. CT was ordered to rule out AAD in 175 (0.7%) patients (mean 62 years, SD 16.5, 50.6% female). Significant variation between physicians ordering was found, with individual physicians ordering varying from 0.6 to 12%.

CONCLUSIONS

Current rate of imaging for acute aortic dissection is low and potentially inefficient, with a large variation in practice. These findings suggest potential for more standardized and efficient use of CT for the diagnosis of acute aortic dissection.

Thoracic Aortic Syndromes

Aortic dissection (AD) is a lethal, treatable disruption of the aortic vessel wall. It often presents without classic features, mimicking symptoms of other conditions, and diagnosis is often delayed. Established high-risk markers of AD should be sought and indicate advanced aortic imaging with CT, MRI, or TEE. Treatment is immediate surgical evaluation, aggressive symptom relief, and reduction of the force of blood against the aortic wall by control of heart rate, followed by blood pressure.

Vascular Causes of Syncope: An Emergency Medicine Review

BACKGROUND

Syncope is a common emergency department (ED) complaint, accounting for 2% of visits annually. A wide variety of etiologies can result in syncope, and vascular causes may be deadly.

OBJECTIVE

This review evaluates vascular causes of syncope and their evaluation and management in the ED.

DISCUSSION

Syncope is defined by a brief loss of consciousness with loss of postural tone and complete, spontaneous recovery without medical intervention. Causes include cardiac, vasovagal, orthostatic, neurologic, medication-related, and idiopathic, and most cases of syncope will not receive a specific diagnosis pertaining to the cause. Emergency physicians are most concerned with life-threatening causes such as dysrhythmia and obstruction, and electrocardiogram is a primary means of evaluation. However, vascular etiologies can result in patient morbidity and mortality. These conditions include pulmonary embolism, subclavian steal, aortic dissection, cerebrovascular disease, intracerebral hemorrhage, carotid/vertebral dissection, and abdominal aortic aneurysm. A focused history and physical examination can assist emergency physicians in determining the need for further testing and management.

CONCLUSIONS

Syncope is common and may be the result of a deadly condition. The emergency physician, through history and physical examination, can determine the need for further evaluation and resuscitation of these patients, with consideration of vascular etiologies of syncope.

Systematic review of emergency medicine clinical practice guidelines: Implications for research and policy

Introduction

Over 25 years, emergency medicine in the United States has amassed a large evidence base that has been systematically assessed and interpreted through ACEP Clinical Policies. While not previously studied in emergency medicine, prior work has shown that nearly half of all recommendations in medical specialty practice guidelines may be based on limited or inconclusive evidence. We sought to describe the proportion of clinical practice guideline recommendations in Emergency Medicine that are based upon expert opinion and low level evidence.

Methods

Systematic review of clinical practice guidelines (Clinical Policies) published by the American College of Emergency Physicians from January 1990 to January 2016. Standardized data were abstracted from each Clinical Policy including the number and level of recommendations as well as the reported class of evidence. Primary outcomes were the proportion of Level C equivalent recommendations and Class III equivalent evidence. The primary analysis was limited to current Clinical Policies, while secondary analysis included all Clinical Policies.

Results

A total of 54 Clinical Policies including 421 recommendations and 2801 cited references, with an average of 7.8 recommendations and 52 references per guideline were included. Of 19 current Clinical Policies, 13 of 141 (9.2%) recommendations were Level A, 57 (40.4%) Level B, and 71 (50.4%) Level C. Of 845 references in current Clinical Policies, 67 (7.9%) were Class I, 272 (32.3%) Class II, and 506 (59.9%) Class III equivalent. Among all Clinical Policies, 200 (47.5%) recommendations were Level C equivalent, and 1371 (48.9%) of references were Class III equivalent.

Conclusions

Emergency medicine clinical practice guidelines are largely based on lower classes of evidence and a majority of recommendations are expert opinion based. Emergency medicine appears to suffer from an evidence gap that should be prioritized in the national research agenda and considered by policymakers prior to developing future quality standards.

Prehospital Care for the Adult and Pediatric Seizure Patient: Current Evidence-based Recommendations

INTRODUCTION

We sought to develop evidence-based recommendations for the prehospital evaluation and treatment of adult and pediatric patients with a seizure and to compare these recommendations against the current protocol used by the 33 emergency medical services (EMS) agencies in California.

METHODS

We performed a review of the evidence in the prehospital treatment of patients with a seizure, and then compared the seizure protocols of each of the 33 EMS agencies for consistency with these recommendations. We analyzed the type and route of medication administered, number of additional rescue doses permitted, and requirements for glucose testing prior to medication. The treatment for eclampsia and seizures in pediatric patients were analyzed separately.

RESULTS

Protocols across EMS Agencies in California varied widely. We identified multiple drugs, dosages, routes of administration, re-dosing instructions, and requirement for blood glucose testing prior to medication delivery. Blood glucose testing prior to benzodiazepine administration is required by 61% (20/33) of agencies for adult patients and 76% (25/33) for pediatric patients. All agencies have protocols for giving intramuscular benzodiazepines and 76% (25/33) have protocols for intranasal benzodiazepines. Intramuscular midazolam dosages ranged from 2 to 10 mg per single adult dose, 2 to 8 mg per single pediatric dose, and 0.1 to 0.2 mg/kg as a weight-based dose. Intranasal midazolam dosages ranged from 2 to 10 mg per single adult or pediatric dose, and 0.1 to 0.2 mg/kg as a weight-based dose. Intravenous/intrasosseous midazolam dosages ranged from 1 to 6 mg per single adult dose, 1 to 5 mg per single pediatric dose, and 0.05 to 0.1 mg/kg as a weight-based dose. Eclampsia is specifically addressed by 85% (28/33) of agencies. Forty-two percent (14/33) have a protocol for administering magnesium sulfate, with intravenous dosages ranging from 2 to 6 mg, and 58% (19/33) allow benzodiazepines to be administered.

CONCLUSION

Protocols for a patient with a seizure, including eclampsia and febrile seizures, vary widely across California. These recommendations for the prehospital diagnosis and treatment of seizures may be useful for EMS medical directors tasked with creating and revising these protocols.

Risk stratification using D-dimers in patients presenting to the emergency department with nonspecific complaints

BACKGROUND

Patients with nonspecific complaints (NSC) such as generalized weakness present frequently to acute care settings. These patients are at risk of adverse health outcomes. The aim of our study was to test the hypothesis whether D-dimers are predictive for 30-day mortality in patients with NSCs.

METHODS

Delayed type cross-sectional diagnostic study with a 30-day follow-up period, registered with ClinicalTrials.gov (NCT00920491). This study took place in 2 EDs in Northwestern Switzerland. Patients were enrolled in the study if they were over 18years of age, gave informed consent, and if they presented with NSCs such as generalized weakness. D-dimer levels were determined at ED presentation.

RESULTS

The final study population consisted of 524 patients. Median age was 82years (IQR=75 to 87years); 40.5% were men. There were 489 survivors and 35 non-survivors at 30-day follow-up. Twenty-one (60%) of the non-survivors were males. D-dimer levels were significantly higher in non-survivors than in survivors (p<0.001). Univariate Cox regression models for D-dimer resulted in a C-index of 0.77 for prediction of mortality. A model including sex, age, Katz ADL and D-dimer in a multivariate Cox regression lead to a C-Index of 0.80.

CONCLUSION

D-dimer testing might be an effective risk stratification tool in patients with NSC by helping to identify patients at low risk of short-term mortality with a sensitivity of 0.97 and a negative likelihood ratio of 0.121. The use of D-dimers for risk stratification in patients with NSC should be confirmed with prospective studies.

Acute Stroke: Current Evidence-based Recommendations for Prehospital Care

Introduction

In the United States, emergency medical services (EMS) protocols vary widely across jurisdictions. We sought to develop evidence-based recommendations for the prehospital evaluation and treatment of a patient with a suspected stroke and to compare these recommendations against the current protocols used by the 33 EMS agencies in the state of California.

Methods

We performed a literature review of the current evidence in the prehospital treatment of a patient with a suspected stroke and augmented this review with guidelines from various national and international societies to create our evidence-based recommendations. We then compared the stroke protocols of each of the 33 EMS agencies for consistency with these recommendations. The specific protocol components that we analyzed were the use of a stroke scale, blood glucose evaluation, use of supplemental oxygen, patient positioning, 12-lead electrocardiogram (ECG) and cardiac monitoring, fluid assessment and intravenous access, and stroke regionalization.

Results

Protocols across EMS agencies in California varied widely. Most used some sort of stroke scale with the majority using the Cincinnati Prehospital Stroke Scale (CPSS). All recommended the evaluation of blood glucose with the level for action ranging from 60 to 80mg/dL. Cardiac monitoring was recommended in 58% and 33% recommended an ECG. More than half required the direct transport to a primary stroke center and 88% recommended hospital notification.

Conclusion

Protocols for a patient with a suspected stroke vary widely across the state of California. The evidence-based recommendations that we present for the prehospital diagnosis and treatment of this condition may be useful for EMS medical directors tasked with creating and revising these protocols.

Emergency physician focused cardiac ultrasound improves diagnosis of ascending aortic dissection

STUDY OBJECTIVE

Ascending aortic dissection (AAD) is an uncommon, time-sensitive, and deadly diagnosis with a nonspecific presentation. Ascending aortic dissection is associated with aortic dilation, which can be determined by emergency physician focused cardiac ultrasound (EP FOCUS). We seek to determine if patients who receive EP FOCUS have reduced time to diagnosis for AAD.

METHODS

We performed a retrospective review of patients treated at 1 of 3 affiliated emergency departments, March 1, 2013, to May 1, 2015, diagnosed as having AAD. All autopsies were reviewed for missed cases. Primary outcome measure was time to diagnosis. Secondary outcomes were time to disposition, misdiagnosis rate, and mortality.

RESULTS

Of 386547 ED visits, targeted review of 123 medical records and 194 autopsy reports identified 32 patients for inclusion. Sixteen patients received EP FOCUS and 16 did not. Median time to diagnosis in the EP FOCUS group was 80 (interquartile range [IQR], 46-157) minutes vs 226 (IQR, 109-1449) minutes in the non-EP FOCUS group (P = .023). Misdiagnosis was 0% (0/16) in the EP FOCUS group vs 43.8% (7/16) in the non-EP FOCUS group (P = .028). Mortality, adjusted for do-not-resuscitate status, for EP FOCUS vs non-EP FOCUS was 15.4% vs 37.5% (P = .24). Median rooming time to disposition was 134 (IQR, 101-195) minutes for EP FOCUS vs 205 (IQR, 114-342) minutes for non-EP FOCUS (P = .27).

CONCLUSIONS

Patients who receive EP FOCUS are diagnosed faster and misdiagnosed less compared with patients who do not receive EP FOCUS. We recommend assessment of the thoracic aorta be performed routinely during cardiac ultrasound in the emergency department.

Chest Pain of Suspected Cardiac Origin: Current Evidence-based Recommendations for Prehospital Care

Introduction

In the United States, emergency medical services (EMS) protocols vary widely across jurisdictions. We sought to develop evidence-based recommendations for the prehospital evaluation and treatment of chest pain of suspected cardiac origin and to compare these recommendations against the current protocols used by the 33 EMS agencies in the state of California.

Methods

We performed a literature review of the current evidence in the prehospital treatment of chest pain and augmented this review with guidelines from various national and international societies to create our evidence-based recommendations. We then compared the chest pain protocols of each of the 33 EMS agencies for consistency with these recommendations. The specific protocol components that we analyzed were use of supplemental oxygen, aspirin, nitrates, opiates, 12-lead electrocardiogram (ECG), ST segment elevation myocardial infarction (STEMI) regionalization systems, prehospital fibrinolysis and β-blockers.

Results

The protocols varied widely in terms of medication and dosing choices, as well as listed contraindications to treatments. Every agency uses oxygen with 54% recommending titrated dosing. All agencies use aspirin (64% recommending 325mg, 24% recommending 162mg and 15% recommending either), as well as nitroglycerin and opiates (58% choosing morphine). Prehospital 12-Lead ECGs are used in 97% of agencies, and all but one agency has some form of regionalized care for their STEMI patients. No agency is currently employing prehospital fibrinolysis or β-blocker use.

Conclusion

Protocols for chest pain of suspected cardiac origin vary widely across California. The evidence-based recommendations that we present for the prehospital diagnosis and treatment of this condition may be useful for EMS medical directors tasked with creating and revising these protocols.

Overtesting and the Downstream Consequences of Overtreatment: Implications of "Preventing Overdiagnosis" for Emergency Medicine

Overtesting, the downstream consequences of overdiagnosis, and overtreatment of some patients are topics of growing debate within emergency medicine (EM). The "Preventing Overdiagnosis" conference, hosted by The Dartmouth Institute for Health Policy and Clinical Practice, with sponsorship from consumer organizations, medical journals, and academic institutions, is evidence of an expanding interest in this topic. However, EM represents a compellingly unique environment, with increased decision density tied to high stakes for patients and providers with missed or delayed diagnoses in a professional atmosphere that does not tolerate mistakes. This article reviews the relevance of this reductionist paradigm to EM, provides a first-hand synopsis of the first "Preventing Overdiagnosis" conference, and assesses barriers to moving the concept of less test ordering to reality.

White blood cell and platelet count as adjuncts to standard clinical evaluation for risk assessment in patients at low probability of acute aortic syndrome

AIMS

Pre-test probability assessment is key in the approach to suspected acute aortic syndromes (AASs). However, most patients with AAS-compatible symptoms are classified at low probability, warranting further evaluation for decision on aortic imaging. White blood cell count, platelet count and fibrinogen explore pathophysiological pathways mobilized in AASs and are routinely assayed in the workup of AASs. However, the diagnostic performance of these variables for AASs, alone and as a bundle, is unknown. We tested the hypothesis that white blood cell count, platelet count and/or fibrinogen at presentation may be applied as additional tools to standard clinical evaluation for pre-test risk assessment in patients at low probability of AAS.

METHODS AND RESULTS

This was a retrospective observational study conducted on consecutive patients managed in our Emergency Department from 2009 to 2014 for suspected AAS. White blood cell count, platelet count and fibrinogen were assayed during evaluation in the Emergency Department. The final diagnosis was obtained by computed tomography angiography. The pre-test probability of AAS was defined according to guidelines. Of 1210 patients with suspected AAS, 1006 (83.1%) were classified at low probability, and 271 (22.4%) were diagnosed with AAS. Within patients at low probability, presence of at least one alteration among white blood cell count >9*10³/µl, platelet count <200*10³/µl and fibrinogen <350 mg/dl was associated with a sensitivity of 95.5% (89.7-98.5%) and a specificity of 18.3% (15.6-21.2%). In patients at low probability, white blood cell count >9*10³/µl and platelet count <200*10³/µl were found as independent predictors of AAS beyond established clinical risk markers. Within patients at low probability, the estimated risk of AAS based on the number of alterations amongst white blood cell count >9*10³/µl and platelet count <200*10³/µl was 2.7% (1.2-5.7%) with zero alterations, 11.3% (8.8-14.3%) with one alteration and 31.9% (24.8-40%) with two alterations ( p<0.001).

CONCLUSION

In addition to standard clinical evaluation, white blood cell count and platelet count may be used in patients at low pre-test probability to fine-tune risk assessment of AAS.