Pneumomediastinum after lung packing.
Lung packing (glossopharyngeal insufflation) consists of forcing air into the lungs, using glossopharyngeal muscle contractions similar to swallowing. Breath-hold divers perform this technique after a maximal inhalation prior to diving, thus increasing initial lung volume. However, as suggested by previous authors, this breathing maneuver could theoretically lead to lung rupture. Here we report a pneumomediastinum found on chest CT scan in a diver during a physiological study, when glossopharyngeal insufflation increased the volume of gas in the lungs by 1,040 ml (over his total lung capacity); at the same time, his transpulmonary pressures increased up to 4.1 kPa. We discuss the possibility that the very high transpulmonary pressures during lung packing caused this pneumomediastinum.
Jacobson
F L
FL
Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Loring
S H
SH
Ferrigno
M
M
D000328:Adult; D004242:Diving / Q000502:physiology; D006801:Humans; D007327:Insufflation / Q000009:adverse effects* / Q000379:methods; D008297:Male; D008478:Mediastinal Emphysema / Q000000981:diagnostic imaging / Q000209:etiology*; D011859:Radiography