Three Simultaneous Cases of Spontaneous Pneumomediastinum With Epidural Pneumatosis During Vocal Training

Objective. The aim of this study was to describe a case series of three simultaneous cases of spontaneous pneumomediastinum (SPM) with epidural pneumatosis during vocal training. Methods. A report of three cases with chart review was performed. Literature review was carried out using PubMed. Results. This was an extremely rare case series where at least three of the 20 participants of a vocal training in a self- development seminar developed SPM, epidural pneumatosis, pneumothorax, and subcutaneous emphysema. All cases improved with bed rest. Simultaneous cases of SPM have been reported in the past. However, the cause of simultaneous occurrence has not been explained clearly. In our cases, continuous excessive vocal training may have caused intrathoracic pressure to rise, causing SPM at a high prevalence. Epidural pneumatosis is a rare finding. Studies on epidural pneumatosis complicating SPM are limited. Air is said to easily pass through the cervical region owing to the close proximity between the mediastinum and the upper spine, resulting in epidural pneumatosis. Elevated intrathoracic pressure while the glottis is closed may worsen the risk for epidural pneumatosis. In this seminar, continuous effortful vocal training at full pitch with few pauses for breath may have contributed to this simultaneous occurrence. Conclusions. We report three simultaneous cases of SPM and epidural pneumatosis due to demanding vocal training. Further research on this subject is desired to identify risk factors.