DIAGNOSING DIZZINESS IN THE EMERGENCY DEPARTMENT: Why “What do you mean by ‘dizzy’?” Should Not Be the First Question You Ask

Abstract

Dizziness is a complex neurologic symptom reflecting a perturbation of normal balance perception and spatial orientation. It is one of the most common symptoms encountered in general medical practice. Considering the dual impact of symptom-related morbidity (e.g., falls with hip fractures) and direct medical expenses for diagnosis and treatment, dizziness represents a major healthcare burden for society. However, perhaps the dearest price is paid by those individuals who are misdiagnosed, with devastating consequences. Dizziness can be caused by numerous diseases, some of which are dangerous and manifest symptoms almost indistinguishable from benign causes. The risk appears highest among patients with new or severe symptoms, particularly those seeking medical attention in acute-care settings such as the emergency department. Nevertheless, even acute dizziness is more often caused by benign inner ear or cardiovascular disorders. Thus, a major challenge faced by frontline providers is to efficiently identify those patients at high risk of harboring a dangerous underlying disorder. Unfortunately, diagnostic performance in the assessment of dizzy patients is poor. In part, this simply reflects the generally high rates of medical misdiagnosis encountered in frontline settings. However, misdiagnosis of dizziness is disproportionately frequent. Although possible explanations are myriad, I propose that an important cause stems from the pervasive use of an antiquated, oversimplified clinical heuristic to drive diagnostic reasoning in the assessment of dizzy patients. In this dissertation, I contend that the commonly-applied bedside rule that dizziness symptom quality, when grouped into one of four dizziness “types” (vertigo, presyncope, disequilibrium, or ill-defined dizziness), predicts the underlying cause, is false and potentially misleading. The argument supporting this theory is developed in the chapters that follow. Chapter 1 focuses on why dizziness diagnosis presents a significant challenge worthy of our concerted attention. Chapter 2 describes a multi-institutional survey of emergency physicians confirming that the “quality-of-symptoms” approach to dizziness is the dominant paradigm for diagnosis. Chapter 3 describes a cross-sectional study of emergency department dizzy patients demonstrating how this approach is fundamentally flawed. Chapter 4 concludes with a discussion of why this flawed paradigm might have garnered and maintained such widespread acceptance for over three decades.