Morbidity/mortality and economics of hospital-acquired blood stream infections: a controlled study.

A controlled study of mortality, length of hospital stay, and cost of hospitalization in 40 patients with hospital-acquired blood stream infections and 40 similarly ill patients without blood stream infections was done. Patients with septicemia were identified by ongoing routine surveillance, while controls were selected from computer surveys of similarly aged patients matched for primary diagnosis of operation or both. Bacteremic cases for which no matched controls could be obtained and 109 additional cases of blood stream infection occurring after the study period were also characterized to determine any gross bias in the process of case selection. Mortality in bacteremic patients was 38% compared to 10% in controls; median hospital stay was 33 days for bacteremic patients and cost was $6,692, compared to 14 days' hospitalization and $2,322 cost for controls. Mortality among the unmatched cases as well as the 109 additional cases was 34%. The excess morbidity, mortality, and hospitalization costs offer a better estimate of the direct effects of the hospital-acquired blood stream infection.