PNEUMOMEDIASTINUM (Greek pneuma air + lat. mediastinum mediastinum; synonym: emphysema of a mediastinum, mediastinal emphysema) — accumulation of air or gas in cellulose of a mediastinum.
Penetration of air into cellulose mediastinums (see) can come as directly from the atmosphere, and from a digestive tract or respiratory tracts at various injuries, patol, processes, operations. The item quite often arises at the wounds of a neck closed and open injuries of a breast, wounds of retroperitoneal space, ruptures of retroperitoneal departments of a duodenal and large intestine, ruptures of a trachea, bronchial tubes and a gullet or them perforation (see) at hit of foreign bodys, at endoscopic procedures and bougieurage, and also during giving an anesthesia. The perforation of diverticulums, ulcers and cancer tumors of a gullet and trachea, spontaneous ruptures of a gullet, insolvency of seams on a trachea, a bronchial tube, a lung, a gullet can be other reasons of P.
Occurs at P. children seldom. Its main reasons: a lung fever, whooping cough at which hit of air in a mediastinum is caused by a subpleural rupture of tissue of lung, especially at violent emphysema; a rupture of the inborn or acquired cysts of a lung; staphylococcal destruction of a lung. At P. of a pulmonary origin it is often combined with pheumothorax (see), pyopneumothorax.
A special kind of P. is diagnostic P. which is created for pnevmomediastinografiya (see) way of the dosed administration of air, oxygen, carbon dioxide gas or nitrous oxide to cellulose of a mediastinum.
At massive intake of air in cellulose of a mediastinum it first of all extends to a neck, leading to development of hypodermic emphysemas (see). In case of break of air through the thin or damaged pleural leaves development of unilateral or even bilateral pheumothorax is possible. Sometimes air on okolososudisty kletchatochny spaces gets into a cavity of a pericardium (see. Pneumopericardium ). As a result of distribution of air in fabrics and cavities its accumulations already irrespective of borders of anatomic areas — so-called general intersticial emphysema are formed.
A wedge, P.'s manifestations depend on age (children have disorders of breath and blood circulation are more expressed), volume and the speed of intake of air or other gas in a mediastinum, and also on character patol, the process which caused the Item. At slow receipt of small amounts of air the wedge, symptoms can not be, and P. comes to light only at rentgenol, a research. In more expressed cases patients complain of pressure sense or stethalgias, an asthma, an osiplost of a voice. The forced sitting position, cyanosis, tachycardia, arrhythmia, increase or decrease in the ABP, weakening of a cardiac impulse and tones, disappearance of cordial dullness, crepitation in supraclavicular areas are observed. Severe forms of P. usually are followed by big hypodermic emphysema, pheumothorax, intersticial emphysema.
In N.'s diagnosis major importance has rentgenol, a research. On the direct roentgenogram of a thorax in a mediastinum the gas which is moving apart pleural leaves and outlining bodies of a mediastinum clearly is defined.
Special treatment of easy forms P. is not required since air is gradually soaked up. In hard cases the choice to lay down. actions the hl is defined. obr. main reason for the Item. At the menacing situation, regardless of P.'s reason, it is necessary to provide evacuation of air from a mediastinum. For this purpose over jugular cutting of a breast do cross section 3 — 5 cm long, get behind the handle of a breast into the cellulose of a mediastinum impregnated with air and enter into it a thick drainage with multiple side openings. The drainage is connected to system of continuous aspiration (see. Aspiration drainage ).
As a rule, P. which is not connected with severe damage of internals proceeds favorably. In hard cases in the absence of the timely and qualified treatment there can come death from acute heart or cardiopulmonary failure.
Bibliography: Vishnevsky A. A. and Adamyan A. A. Hirurgiya sredostenrshch, M., 1977, bibliogr.; Isakov Yu. F., Stepanov E. A. and Geras-k and V. I. Rukovodstvo's N on thoracic surgery at children, page 37, etc., M., 1978; Petrovsky B. V., Perelman M. I. and To about r about l of e in and N. S. Tracheobronchial surgery, M., 1978, bibliogr.; Feofilov G. JI. To tactics of the surgeon at intense emphysemas of a mediastinum, Hirurgiya, No. 1, page 27, 1960.
M. I. Perelman; S. M. Krivorak (it is put. hir.).