The Role of Selective Digestive Tract Decontamination on Mortality and Respiratory Tract Infections: Conclusion
Only three of the analyzed studies used quantitative cultures of the lower airways obtained by protected specimen brush or telescoping catheters to support the diagnosis of pneumonia. Several investigators have shown that clinical and radiographic criteria may be inaccurate for the diagnosis of nosocomial pneumonia.” This has led to proposed revisions in the criteria utilized for the diagnosis of nosocomial pneumonia, especially in the mechanically ventilated patient. Of course, such errors in diagnosis, if performed systematically and without bias, would be expected to occur in both the SDD-treated patients and the placebo-treated patients.
Another possible explanation concerns patient selection biases, especially if the SDD-treated patients were “sicker” than those in the control group. In all but three of the analyzed studies, scoring systems such as the Acute Physiologic and Chronic Health Evaluation and the Simplified Acute Physiology Score were used to compare the patient groups. In all of these studies, the patient groups were comparable in terms of their prognostic scores, thus making selection biases less likely to account for the observed outcome disparity.
A final explanation for this discrepancy is that acquired respiratory infection may not significantly influence outcome in the critically ill in detail canadian neighbor pharmacy. This hypothesis is supported by the work of Craven and associates who found that although ventilator-associated pneumonia was significantly associated with hospital fatality by univariate analysis, it did not remain significant after adjustment for other variables by stepwise logistic regression. Reidy and Ramsay have gone so far as to suggest that nosocomial respiratory infections may be a “by-product” of the patient’s deteriorating condition without any independent contribution to mortality. These findings are countered by those demonstrated in a recent case-control study where nosocomial pneumonia was found to be associated with mortality in excess of that resulting from the underlying disease alone. This excess mortality was especially remarkable in pneumonias caused by Pseu-domonas and Acinetobacter species in patients having received previous antibiotic therapy. These studies, along with a recent multivariate analysis of ventilator-associated pneumonia, suggest that prior antibiotic usage may have an important influence on both the occurrence and outcome of acquired pneumonia in the ICU.
Category: Respiratory Symptoms
Tags: acquired infections, gram-positive bacteria, pneumonia, respiratory infection, tracheobronchitis