Spontaneous pneumomediastinum is defined as the presence of free air in the mediastinum
without any apparent concomitant factors or disease. It is uncommon but usually benign
and self-limiting. Generally, patients with spontaneous pneumomediastinum are admitted
to hospital, and occasionally, prophylactic antibiotics are administered to prevent
mediastinitis. The purpose of this study was to describe practices concerning the
feasibility of outpatient treatment and follow-up of spontaneous pneumomediastinum
and the necessity of prophylactic antibiotics.
We conducted this study in a single emergency medical center located in Kobe, Japan.
We retrospectively evaluated patients with spontaneous pneumomediastinum from January
2007 to December 2014. Spontaneous pneumomediastinum was defined as cases in which
pneumomediastinum did not occur in the setting of positive pressure ventilation or
severe trauma. All case records were carefully reviewed considering the demographic
data, symptoms, precipitating events, diagnostic workup performed, use of prophylactic
antibiotics, length of hospital stay, and complications.
Thirty-four patients who satisfied the inclusion criteria were identified. Twenty-three
patients (67.6%) were followed up on an outpatient basis, and 11 patients (32.4%)
were admitted to the hospital, with a mean length of stay of 3.4 days. Prophylactic antibiotics were orally administered to 2 patients. None of the
patients developed complications, such as tension pneumomediastinum, delayed pneumothorax,
airway compromise, and mediastinitis.
Spontaneous pneumomediastinum is a benign condition presenting primarily in young
adults, with an uneventful recovery. Therefore, patients may recover from this condition
without admission or the need for prophylactic antibiotics.