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Complications of Central Venous Catheterization.

To the Editor: The results of the randomized trial by Parienti et al. (Sept. 24 issue)1 comparing insertion sites for central venous catheterization will help guide clinicians in their choice of sites. We were surprised, however, that the authors did not report the number of patients in each insertionsite group who were receiving positive-pressure ventilation. The increased positive end-expiratory pressure and large tidal volumes associated with mechanical ventilation can predispose a patient to the development of pneumothorax. Some evidence suggests that the risk of pneumothorax from subclavian-vein catheterization may be higher among patients receiving positive-pressure ventilation than among those not receiving it.2 Without knowing how the outcomes are stratified according to ventilation status, it is hard to fairly assess the true risk profile of subclavian-vein access. The authors correctly observe that “the cumulative risk of infectious and thrombotic complications increases with increasing catheter exposure.” We think the inference is worth stating more plainly: one means of preventing infectious complications from central venous catheterization is prompt removal of the catheter when it is no longer needed.3 David R. Vinson, M.D. Dustin W. Ballard, M.D., M.B.E. Permanente Medical Group Oakland, CA drvinson@ ucdavis . edu