© 2005 American Thoracic Society
Should We Start Considering Surfactant for Atelectasis?From the Authors:We thank Dr. Tsangaris and colleagues for their interest in our article (1). Tsangaris and colleagues analyzed the bronchoalveolar lavage (BAL) fluid obtained from atelectatic lung regions of eight mechanically ventilated patients, and found clear signs of increased permeability, inflammation and surfactant alterations (2). These changes in the BAL fluid correlated with the duration of atelectasis and showed considerable overlap with ventilator-associated pneumonia (VAP). Their findings offer important clinical support for the role of atelectasis and surfactant dysfunction in the pathogenesis of VAP. As suggested by Tsangaris and colleagues, exogenous surfactant seems to be the next logical step in reducing the incidence of VAP in ventilated patients. However, several variables that might influence the efficacy of exogenous surfactant should be considered when designing future clinical trials. First, the surfactant dose should be sufficient to overcome possible inhibition by proteins present in the alveolar compartment. Both experimental and clinical data show that protein levels in the alveolar space are increased during VAP (1, 2). Second, the data from Tsangaris and colleagues indicate that the duration of atelectasis might be a crucial factor in the development of VAP. This finding would suggest that treatment with exogenous surfactant early in the course of disease might prove more efficacious than late selective treatment. Finally, as mentioned by Tsangaris and colleagues, the ventilation strategy applied following surfactant treatment could also affect its efficacy and preservation (3). This is also indicated by our experimental study showing that exogenous surfactant combined with an open lung ventilation strategy is more efficacious in attenuating bacterial growth and translocation than either therapy alone (1). Exogenous surfactant may also serve as a vehicle for local administration of other agents, such as antibiotics or immunoglobulins, into the lung, which may offer additional advantages in the treatment of VAP (4, 5). However, despite these promising experimental and clinical observational studies, we fully agree with Tsangaris and colleagues that future clinical trials are necessary to investigate the role of exogenous surfactant in the treatment of mechanically ventilated patients at risk for VAP.
a Erasmus MC-Faculty, Rotterdam, The Netherlands FOOTNOTES Conflict of Interest Statement: A.v.K. has participated as a speaker in scientific meetings or courses organized and financed by pharmaceutical companies Boehringer Ingelheim and Nycomed, and received financial support for experimental research; R.L. does not have a financial relationship with a commercial entity that has an interest in the subject of this manuscript; E.H. has participated as a speaker in scientific meetings or courses organized and financed by various pharmaceutical companies (Chiesi, Abbott, Boehringer, Altana, and Draeger), and has two industry sponsored grants pending (Altana Pharma and Chiesi); A.D.J. does not have a financial relationship with a commercial entity that has an interest in the subject of this manuscript; F.v.I. does not have a financial relationship with a commercial entity that has an interest in the subject of this manuscript; A.N. does not have a financial relationship with a commercial entity that has an interest in the subject of this manuscript; J.K. does not have a financial relationship with a commercial entity that has an interest in the subject of this manuscript; J.H. does not have a financial relationship with a commercial entity that has an interest in the subject of this manuscript; B.L. is a member of the Advisory Board of Halas Pharma GmbH and has shares in that same company and received a research grant from Leo Pharma for surfactant research. REFERENCES
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