mediastinal flutter

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Related to mediastinal flutter: mediastinal shift


a rapid vibration or pulsation.
atrial flutter a cardiac arrhythmia in which the atrial contractions are rapid (230–380 per minute), but regular. Two types, I and II, are distinguished according to rate; Type I is also more amenable to cardioversion. In Type I the atrial rate is usually 290 to 310 per minute but can range from 230 to 350. In Type II the atrial rate is usually 360 to 380 per minute but can range from 340 to 430.
diaphragmatic flutter peculiar wavelike fibrillations of the diaphragm of unknown cause.
impure flutter atrial flutter in which the atrial rhythm is irregular.
mediastinal flutter see mediastinal flutter.
pure flutter atrial flutter in which the atrial rhythm is regular.
ventricular flutter a possible transition stage between ventricular tachycardia and ventricular fibrillation, the electrocardiogram showing rapid, uniform, and virtually regular oscillations, 250 or more per minute.


of or pertaining to the mediastinum.
mediastinal flutter movement of the tissues and organs of the mediastinum back and forth with each movement of air into and out of an open sucking wound in the thoracic cavity. The condition can produce serious impairment of cardiopulmonary function and is fatal if not treated promptly. Symptoms are similar to those of mediastinal shift.
mediastinal shift a shifting or moving of the tissues and organs that comprise the mediastinum (heart, great vessels, trachea, and esophagus) to one side of the chest cavity. The condition occurs when a severe injury to the chest causes the entrapment of air in the pleural space (tension pneumothorax). As the volume of air increases on the affected side, the lung collapses and the organs and tissues of the mediastinum are crowded to the opposite side of the chest. This can produce compression of the other lung and kinking or twisting of one or more of the great blood vessels, which in turn seriously impairs blood flow to and from the heart.

Symptoms of mediastinal shift include severe dyspnea, cyanosis, displacement of the trachea to one side, and distended neck veins. The immediate treatment is insertion of a hollow needle or trocar into the pleural space (thoracentesis) to provide an outlet for the escape of air and fluid. After the trapped air is released, closed chest drainage is initiated to allow for reexpansion of the lung.
Mediastinal shift. As air from a pneumothorax is drawn into the chest cavity, it places pressure on the trachea, heart, and great vessels, causing them to shift from their normal anatomic positions. From Polaski and Tatro, 1996.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

mediastinal flutter

Abnormal side-to-side motion of the mediastinum during respiration.
See also: flutter
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