Local activation of coagulation and inhibition of fibrinolysis in the lung during ventilator associated pneumonia
- 1Department of Intensive Care Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- 2Laboratory of Experimental Internal Medicine, Academic Medical Center, University of Amsterdam
- 3Intensive Therapy Unit, John Radcliffe Hospital, Oxford, UK
- 4Department of Internal Medicine, Academic Medical Center, University of Amsterdam
- 5Department of Pathophysiology of Plasma Proteins, Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, Amsterdam, The Netherlands
- 6Clinical Epidemiology and Biostatistics, Academic Medical Center, University of Amsterdam
- 7Department of Infectious Diseases, Tropical Medicine and AIDS, Academic Medical Center, University of Amsterdam
- Correspondence to:
Dr M J Schultz
Academic Medical Center, University of Amsterdam, Department of Intensive Care Medicine, C3-329, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands;
- Received 26 July 2003
- Accepted 6 August 2003
Background: Fibrin deposition is a hallmark of pneumonia. To determine the kinetics of alterations in local coagulation and fibrinolysis in relation to ventilator associated pneumonia (VAP), a single centre prospective study of serial changes in pulmonary and systemic thrombin generation and fibrinolytic activity was conducted in patients at risk for VAP.
Methods: Non-directed bronchial lavage (NBL) was performed on alternate days in patients expected to require mechanical ventilation for more than 5 days. A total of 28 patients were studied, nine of whom developed VAP.
Results: In patients who developed VAP a significant increase in thrombin generation was observed in the airways, as reflected by a rise in the levels of thrombin-antithrombin complexes in NBL fluid accompanied by increases in soluble tissue factor and factor VIIa concentrations. The diagnosis of VAP was preceded by a decrease in fibrinolytic activity in NBL fluid. Indeed, before VAP was diagnosed clinically, plasminogen activator activity levels in NBL fluid gradually declined, which appeared to be caused by a sharp increase in NBL fluid levels of plasminogen activator inhibitor 1.
Conclusion: VAP is characterised by a shift in the local haemostatic balance to the procoagulant side, which precedes the clinical diagnosis of VAP.
- NBL, non-directed bronchial lavage
- PAA, plasminogen activator activity
- PAI-1, plasminogen activator inhibitor type 1
- TATc, thrombin-antithrombin complexes
- TF, tissue factor
- t-PA, tissue type plasminogen activator
- u-PA, urokinase type plasminogen activator
- VAP, ventilator associated pneumonia
This study was funded in part by the Oxford Health Services Research Committee (research project number 593).