Evaluation of the Canadian Clinical Practice Guidelines Risk Prediction Tool for Acute Aortic Syndrome: The RIPP Score.

Introduction: Acute aortic syndrome (AAS) is a rare clinical syndrome with a high mortality rate. The Canadian clinical practice guideline for the diagnosis of AAS was developed in order to reduce the frequency of misdiagnoses. As part of the guideline, a clinical decision aid was developed to facilitate clinician decision-making (RIPP score). The aim of this study is to validate the diagnostic accuracy of this tool and assess its performance in comparison to other risk prediction tools that have been developed. Methods: This was a historical case-control study. Consecutive cases and controls were recruited from three academic emergency departments from 2002-2020. Cases were identified through an admission, discharge, or death certificated diagnosis of acute aortic syndrome. Controls were identified through presenting complaint of chest, abdominal, flank, back pain, and/or perfusion deficit. We compared the clinical decision tools' C statistic and used the DeLong method to test for the significance of these differences and report sensitivity and specificity with 95% confidence intervals. Results: We collected data on 379 cases of acute aortic syndrome and 1340 potential eligible controls; 379 patients were randomly selected from the final population. The RIPP score had a sensitivity of 99.7% (98.54-99.99). This higher sensitivity resulted in a lower specificity (53%) compared to the other clinical decision aids (63-86%). The DeLong comparison of the C statistics found that the RIPP score had a higher C statistic than the ADDRS (-0.0423 (95% confidence interval -0.07-0.02); P < 0.0009) and the AORTAs score (-0.05 (-0.07 to -0.02); P = 0.0002), no difference compared to the Lovy decision tool (0.02 (95% CI -0.01-0.05 P < 0.25)) and decreased compared to the Von Kodolitsch decision tool (0.04 (95% CI 0.01-0.07 P < 0.008)). Conclusion: The Canadian clinical practice guideline's AAS clinical decision aid is a highly sensitive tool that uses readily available clinical information. It has the potential to improve diagnosis of AAS in the emergency department.

The use and misuse of the Dix-Hallpike test in the emergency department.

OBJECTIVES: A simple bedside test, the Dix-Hallpike test (DHT), can reliably diagnose benign paroxysmal positional vertigo (BPPV) in patients with acute onset dizziness or vertigo. We evaluated patterns of DHT use by emergency physicians in patients presenting with dizziness and vertigo. Our objective was to assess the frequency and clinically appropriate use of the DHT in an emergency department. METHODS: A health records review was performed using data from patients who presented to a tertiary care emergency department between September 2014 and March 2018 with a primary complaint of vertigo or dizziness. Patient records were reviewed for documentation of symptoms consistent with BPPV and DHT usage. RESULTS: A total of 2309 patients met inclusion criteria. Of all dizzy patients who had complete documentation of signs and symptoms consistent with BPPV, 53% were assessed with a DHT. Of 469 patients who received a DHT, 134 (29%) of tests were done on patients who had documentation of at least one characteristic that was inconsistent with a diagnosis of BPPV. Eight patients who received a DHT were ultimately diagnosed with a central cause for their vertigo. CONCLUSIONS: The DHT is both underutilized and frequently applied to patients whose symptoms are not consistent with BPPV. This may result in prolonged patient discomfort and increased resource utilization, as well as increasing the risk of misdiagnosing central vertigo.

RéSUMé: OBJECTIFS: Un simple test de chevet, le test de Dix-Hallpike (DHT), peut diagnostiquer de manière fiable le vertige positionnel paroxystique bénin (VPPB) chez les patients présentant des étourdissements ou des vertiges d'apparition aiguë. Nous avons évalué les modèles d'utilisation de la DHT par les médecins d'urgence chez les patients présentant des étourdissements et des vertiges. Notre objectif était d'évaluer la fréquence et l'utilisation cliniquement appropriée du DHT dans un service d'urgence. MéTHODES: Un examen des dossiers de santé a été réalisé à partir des données de patients qui se sont présentés à un service d'urgence de soins tertiaires entre septembre 2014 et mars 2018 avec une plainte principale de vertige ou d'étourdissements. Les dossiers des patients ont été examinés afin de documenter les symptômes correspondant à l'utilisation du VPPB et de la DHT. RéSULTATS: Au total, 2 309 patients répondaient aux critères d'inclusion. Parmi tous les patients qui avaient des étourdissements et qui avaient une documentation complète des signes et des symptômes compatibles avec le VPPB, 53 % ont été évalués au moyen d'un DHT. Sur 469 patients qui ont reçu une DHT, 134 (29 %) des tests ont été effectués sur des patients qui avaient une documentation d'au moins une caractéristique incompatible avec un diagnostic de VPPB. Huit patients qui ont reçu une DHT ont finalement été diagnostiqués avec une cause centrale pour leur vertige. CONCLUSIONS: La DHT est à la fois sous-utilisée et fréquemment appliquée aux patients dont les symptômes ne correspondent pas au VPPB. Il peut en résulter une gêne prolongée pour le patient et une utilisation accrue des ressources, ainsi qu'un risque accru de diagnostic erroné du vertige central.

Diagnostic Accuracy of the HINTS Exam in an Emergency Department: A Retrospective Chart Review.

INTRODUCTION: The HINTS exam is a series of bedside ocular motor tests designed to distinguish between central and peripheral causes of dizziness in patients with continuous dizziness, nystagmus, and gait unsteadiness. Previous studies, where the HINTS exam was performed by trained specialists, have shown excellent diagnostic accuracy. Our objective was to assess the diagnostic accuracy of the HINTS exam as performed by emergency physicians on patients presenting to the emergency department (ED) with a primary complaint of vertigo or dizziness. METHODS: A retrospective cohort study was performed using data from patients who presented to a tertiary care ED between September 2014 and March 2018 with a primary complaint of vertigo or dizziness. Patient characteristics of those who received the HINTS exam were assessed along with sensitivity and specificity of the test to rule out a central cause of stroke. RESULTS: A total of 2,309 patients met criteria for inclusion in the study. Physician uptake of the HINTS exam was high, with 450 (19.5%) dizzy patients receiving all or part of the HINTS. A large majority of patients (96.9%) did not meet criteria for receiving the test as described in validation studies; most often this was because patients lacked documentation of nystagmus or described their symptoms as intermittent. In addition, many patients received both HINTS and Dix-Hallpike exams, which are intended for use in mutually exclusive patient populations. In no case was dizziness due to a central cause identified using the HINTS exam. CONCLUSIONS: Our results suggest that despite widespread use of the HINTS exam in our ED, its diagnostic value in that setting was limited. The test was frequently used in patients who did not meet criteria to receive the HINTS exam (i.e., continuous vertigo, nystagmus, and unsteady gait). Additional training of emergency physicians may be required to improve test sensitivity and specificity.