The use of antimicrobials in ten Australian and New Zealand intensive careunits

A prospective standardized collection of clinical! microbiological and phar maceutical information on antibiotic use was conducted in Australia and New Zealand intensive care units (ICUs) involving 481 consecutive critically i ll patients who were receiving antibiotics for ally reason while in ICU, Pa tients had a mean SAPS II score of 34.1 +/- 17.8 with an expected mortality of 15.6% (actual mortality 12%). Of these, 292 (60.8%) were admitted to to ICU within 72 hours of surgery. Among such surgical patients, 233 (79.9%) received antibiotics for "surgical prophylaxis" while in ICU (48% of sample population). The second largest group of patients treated with antibiotics bl ICU included those with systemic inflammatory response syndrome and cli nical suspicion of infection (38%). Antibiotics were prescribed for the tre atment of clinically diagnosed infection in 268 patients. Clinical response was apparent in 62.6% and in most (71%) was achieved in the first 72 hours of treatment. The incidence of antimicrobial-related side-effects was 4%, mostly in the form of diarrhoea or rash (75% of all side-effects). The most commonly prescribed anti-microbials were gentamicin (n=146), ceftriaxone ( n=98), vancomycin (n=94) and metronidazole (n=111), Three times daily presc ription of aminoglycosides was uncommon (<1%), Forty-one patients had a doc umented infection (positive culture) with a gram-negative organism. Of thes e, 17 received therapy with a single antibiotic and 24 received therapy wit h two antibiotics. Despite similar illness severity, there were six deaths in former mer group and only two in the latter.