THE COURSE OF NOSOCOMIAL OROPHARYNGEAL COLONIZATION IN PATIENTS RECOVERING FROM ACUTE RESPIRATORY-FAILURE

We sought to determine the duration of nosocomially acquired Gram-nega tive bacilli (GNB) oropharyngeal colonization following hospitalizatio n for acute respiratory failure (ARF). We selected 24 inpatients recov ering from ARF who had positive oropharyngeal cultures for GNB. Follow -up cultures were obtained at the time of hospital discharge, and 2 an d 4 weeks afterwards. The prevalence of GNB colonization in these pati ents was 14/21 (67 percent) at the time of hospital discharge and 14/2 3 (60 percent) 2 weeks afterwards. Both rates were greater than the co ntrol populations 7/30 (23 percent, p<0.02 and <0.05, respectively). F our weeks after hospital discharge, the prevalence of colonization had fallen to 7/19 (37 percent) which was not significantly different fro m that of controls. Five of 24 subjects were rehospitalized during the follow-up period. Pneumonia was diagnosed in only two of the five and both proved to be due to pathogens other than GNB. We conclude that t he prevalence of GNB oropharyngeal colonization following ARF approach es control levels within four weeks of hospital discharge. We speculat e that a post-ARF patient's risk for GNB pneumonia similarly declines.