Pulmonology approach in the investigation of chronic unexplained dyspnea

• Autor(a) principal: Berton,Danilo Cortozi
• Data de Publicação: 2021
• Outros Autores: Mendes,Nathalia Branco Schweitzer, Olivo-Neto,Pedro, Benedetto,Igor Gorski, Gazzana,Marcelo Basso
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Jornal Brasileiro de Pneumologia (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1806-37132021000100500
• topic: Dyspnea; Exercise test; Bronchial provocation tests; Vascular diseases

ABSTRACT Chronic unexplained dyspnea and exercise intolerance represent common, distressing symptoms in outpatients. Clinical history taking and physical examination are the mainstays for diagnostic evaluation. However, the cause of dyspnea may remain elusive even after comprehensive diagnostic evaluation-basic laboratory analyses; chest imaging; pulmonary function testing; and cardiac testing. At that point (and frequently before), patients are usually referred to a pulmonologist, who is expected to be the main physician to solve this conundrum. In this context, cardiopulmonary exercise testing (CPET), to assess physiological and sensory responses from rest to peak exercise, provides a unique opportunity to unmask the mechanisms of the underlying dyspnea and their interactions with a broad spectrum of disorders. However, CPET is underused in clinical practice, possibly due to operational issues (equipment costs, limited availability, and poor remuneration) and limited medical education regarding the method. To counter the latter shortcoming, we aspire to provide a pragmatic strategy for interpreting CPET results. Clustering findings of exercise response allows the characterization of patterns that permit the clinician to narrow the list of possible diagnoses rather than pinpointing a specific etiology. We present a proposal for a diagnostic workup and some illustrative cases assessed by CPET. Given that airway hyperresponsiveness and pulmonary vascular disorders, which are within the purview of pulmonology, are common causes of chronic unexplained dyspnea, we also aim to describe the role of bronchial challenge tests and the diagnostic reasoning for investigating the pulmonary circulation in this context.