[Use of antimicrobial agents and prevalence of infection at the Clinical University Hospital of Zaragoza].

Two cross-sectional prevalence studies have been performed on april 10 and June 12, 1986, at the Hospital Clínico Universitario of Zaragoza in order to gather information about the use and consumption of antimicrobial drugs and the degree of hospital infection. On these days, of the 726 and 717 patients admitted to the hospital, 29.3% and 26.3% were treated with antimicrobial drugs and, of these, 31.4% and 23.8% respectively, with associate drugs (above all empirical purposes and for respiratory infections), aminoglycosides being the most common. The indication of antimicrobial drugs was distributed in the following manner on both days: prophylactic 28.7% and 25.1%, empirical 42.3% and 56.9% and therapeutical 27.9% and 17.6%. The prophylactic treatments were correct in 46.1% and 36.6% of the cases, and of those 74.3% and 71.6% were for surgical prophylaxis; the average time was 3.5 and 4.5 days on each day studied. The most commonly used antimicrobial drugs were, in decreased order: gentamicin, amoxycilin, ampicillin, cefoxitin, pipemidic acid and cefamandol. The consumption was 1.36 and 1.29 drugs per patient on each day. The most common routes of administration were I.V. and oral. The intervals and dosages were generally respected. The most frequent were respiratory and urinary infections, and of these, 21% and 32% of the respiratory infections were nosocomial as were 23% and 32% of the urinary infection. 7.1% and 4.3% of the patients admitted developed a hospital-acquired infection on each day. The most frequent isolated germs were Escherichia coli and Pseudomonas aeruginosa. There were no adverse reactions to the antimicrobial drugs documented.