We have substantial experience with suppression of bacterial growth in chronic lung disease by the use of colistin aerosol. VAP with highly resistant Gram negative organisms has become a major clinical problem in the last few years. We report here the results of our efforts to treat such infections with direct instillation of colistin solution in patients with artificial airways.
Retrospective chart review of 11 patients in our institution who had VAP with Gram negative bacilli resistant to all available systemic antibiotics. Patients were given colistin by direct instillation of 50 mg in 50 ml of saline via catheters passed through their endotracheal or tracheostomy tube, localized according to the distribution of pulmonary infiltrates. Roentgenographic, hemodynamic, microbiologic, hematologic and serum chemistry data before and after colistin instillation were recorded, as were vital signs, demographics and outcome. No antibiotic therapy other than local colistin was administered.
Of the 11 patients who were treated with local instillation of colistin, 8 recovered and were discharged, while 3 died. All patients improved or completely resolved their pulmonary infiltrates after colistin instillation except one patient whose post-treatment chest x-ray was not conclusive due to fluid overload. Sputum cultures were sterilized in all 11 patients. Fever and systemic signs resolved in all patients. WBC count improved significantly in 8 patients. No toxicity was detected. The 3 deaths were unrelated to infection.
Local instillation of colistin is an effective treatment for VAP caused by highly resistant Gram negative organisms.
This treatment should be considered in severe pulmonary infections caused by highly resistant Gram negative organisms, especially when they occur in patients with artificial airways.
W.D. Marino, None.