Λεξικό .. Bronchoalveolar lavage (BAL)

Bronchoalveolar lavage (BAL) is a technique for taking samplesof the detachable cells and acellular lining secretions of the human respiratory tract. bronchoalveolar lavage (BAL) is a means of obtaining relevant components from the airways and alveolar areas for research use and clinical analysis in normals (controls) and patients with a wide spectrum of interstitial lung diseases (ILDs) [1].

From a diagnostic point of view the bronchoalveolar space is the most important because it is easily accessible in laboratory animals, as well as in patients, using BAL. Although this technique has been used for several decades it is still unclear to what extent the BAL represents changes in other lung compartments[2].

Whereas BAL findings continue to impact on understanding disease pathogenesis and this may be its major use now, BAL fluid components, cells in particular, are not correlated well with activity of disease nor for monitoring disease progress or response to treatment. For a few rarer ILDs, BAL fluid characteristics may strongly support a diagnosis [2].

BAL has been used in the treatment of acute and chronic asthma. The rational for its use in acute asthma is the removal of the mucus plugs which the patient may be unable to cough up. Certainly it is not a routine treatment. It is a desperate measure to be turned to when an asthmatic continues to present problems after being placed on a ventilator. The simplest lavage consists of injecting fluid down an endotracheal tube and then aspirating it back. A formal lavage consists of isolating a lobe or segment with a specialized endotracheal tube, or by wedging the fiberoptic bronchoscope. Large quantities of fluid are then instilled into the isolated area, trying to free the mucus plugs and suck them out. BAL is useful in the study of bronchial inflammation allowing collection of cells and other constituents from the epithelial lining fluid [3].

References

1.Tschernig T, Pabst R. What is the clinical relevance of different lung compartments? BMC Pulm Med. 2009 Aug 11;9(1):39.

2. Reynolds HY. Present status of bronchoalveolar lavage in interstitial lung disease. Curr Opin Pulm Med. 2009 Sep;15(5):479-85.

3.Djukanovic, R., et al: Mucosal inflammation in asthma. Am. Rev. Respir. Dis. 1990:142:434-457.