pneumothorax

The presence of free air or gas in the pleural cavity. [G. pneuma, air, + thorax]

- artificial p. p. produced by the injection of air, or a more slowly absorbed gas such as nitrogen, into the pleural space; formerly used for collapse therapy of tuberculosis. SYN: therapeutic p..

- catamenial p. p. occurring in young women during menstruation, usually on the right side.

- extrapleural p. the presence of a gas between the endothoracic fascia-pleural layer and the adjacent chest wall.

- iatrogenic p. p. caused by a medical procedure, most often central venous catheter insertion, thoracentesis, or transbronchial and transthoracic lung biopsy.

- open p. a free communication between the atmosphere and the pleural space either via the lung or through the chest wall. SYN: sucking chest wound.

- pressure p. SYN: tension p..

- p. simplex p., without known cause, in an otherwise healthy person.

- spontaneous p. p. occurring without iatrogenic or other trauma; primary spontaneous p. generally occurs in young people with apical blebs but otherwise normal lungs; secondary spontaneous p. occurs in people with underlying lung disease, most commonly chronic obstructive pulmonary disease and, less often, interstitial lung disease, pneumonia, lung abscess, and lung tumors.

- tension p. a p. in which air enters the pleural cavity and is trapped during expiration; intrathoracic pressure builds to levels higher than atmospheric pressure, compresses the lung, and may displace the mediastinum and its structures toward the opposite side, with consequent cardiopulmonary impairment. SYN: pressure p..

- therapeutic p. SYN: artificial p..

- traumatic p. p. caused by blunt or penetrating chest injury.

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pneu·mo·tho·rax .n(y)ü-mə-'thō(ə)r-.aks, -'thȯ(ə)r- n, pl -tho·rax·es or -tho·ra·ces -'thōr-ə-.sēz a condition in which air or other gas is present in the pleural cavity and which occurs spontaneously as a result of disease or injury of lung tissue, rupture of air-filled pulmonary cysts, or puncture of the chest wall or is induced as a therapeutic measure to collapse the lung see TENSION PNEUMOTHORAX compare OLEOTHORAX

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n.

air in the pleural cavity. Any breach of the lung surface or chest wall allows air to enter the pleural cavity, causing the lung to collapse. The leak can occur without apparent cause, in otherwise healthy people (spontaneous pneumothorax), or result from injuries to the chest (traumatic pneumothorax). In tension pneumothorax a breach in the lung surface acts as a valve, admitting air into the pleural cavity when the patient breathes in but preventing its escape when he breathes out. This air must be let out by surgical incision.

A former treatment for pulmonary tuberculosis - artificial pneumothorax - was the deliberate injection of air into the pleural cavity to collapse the lung and allow the tuberculous areas to heal.

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pneu·mo·tho·rax (noo″mo-thorґaks) [pneumo- + thorax] an accumulation of air or gas in the pleural space; three types are distinguished: traumatic p., primary spontaneous p., and secondary spontaneous p. It was formerly sometimes induced for treatment of pulmonary tuberculosis; see artificial p.