pulmonary sequestration

sequestration

 [se″kwes-tra´shun]

1. abnormal separation of a part from a whole, as a portion of a bone by a pathologic process, or a portion of the circulating blood in a specific part occurring naturally or produced by application of a tourniquet.

2. isolation of a patient.

pulmonary sequestration loss of connection of lung tissue, and sometimes bronchi, with the bronchial tree and pulmonary veins, the tissue receiving its arterial supply from the systemic circulation. It may be completely separated anatomically and physiologically from normally connected lung (extralobar) or contiguous to and partly surrounded by normal lung (intralobar). Called also accessory lung.

Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

pulmonary sequestration

 An uncommon–1:1000 adult lobectomy specimens congenital anomaly characterized by misplaced lung parenchyma, which lacks normal communication with the main tracheobronchial tree that may be intralobar or extralobar

Pulmonary sequestration  

   Intralobar Extralobar

Separate pleura No Yes

Location  Posterior basilar Above or below diaphragm

Age of onset 50% > 20 years  60% < one year

Symptoms  Recurrent pneumonia Respiratory distress

Laterality 60% left  90% left

♂:♀ ratio 1:1 4:1

Other defects Uncommon  > 50%, eg diaphragmatic

         defects, tuberous sclerosis

Bronchial
communication Uncommon, small  None

Arterial supply  Systemic; single aorta Systemic; multiple, small

Venous drainage Inferior pulmonary Systemic; azygous and
        vein          hemiazygous vein

McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

pulmonary sequestration

A nonfunctioning area of the lung that receives its blood supply from the systemic circulation.

See also: sequestration

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