Impact of hospital-wide infection rate, invasive procedures use and antimicrobial consumption on bacterial resistance inside an intensive care unit

Summary We performed a 30-month ecological study to determine the impact of hospital-wide antibiotic consumption, invasive procedure use and hospital-acquired infections (HAIs) on antibiotic resistance in an intensive care unit (ICU). Microbiological isolates from ICU patients with established diagnosis of hospital infection were monitored throughout the study. Overall hospital consumption per 100 patient-days of piperacillin-tazobactam, fluoroquinolones and cephalosporins increased from 1.9 to 2.3 defined daily doses (DDD) ( P P P N =466) of isolates, with increasing resistance demonstrated for meropenem-resistant Klebsiella spp. ( P =0.01) and meropenem-resistant Acinetobacter spp. ( P =0.02). There was a positive correlation between multiresistance rate and DDD of cephalosporins ( P P =0.03). The rate of ceftazidime-resistant Klebsiella spp. correlated with DDD of fluoroquinolones and cephalosporins; the rate of ceftazidime-resistant Pseudomonas spp. correlated with consumption of cephalosporins, and rate of meticillin-resistant Staphylococcus aureus (MRSA) correlated with fluoroquinolone use. During the studied period, 36.9% ( P P