Sensitivity and specificity of blood cultures obtained through intravascular catheters.

The reliability of blood cultures obtained through indwelling intravascular catheters is controversial. In this study, the results of 200 catheter blood cultures were compared with those of an equal number of peripheral blood cultures drawn at the same time. Catheter blood cultures were found to be 96% sensitive (95% confidence interval, 89% to 100%) and 98% specific (95% confidence interval, 96% to 100%) for the detection of septicemia. Factors thought to have influenced these favorable results were the relatively short duration of catheter placement and the particular emphasis given to aseptic technique.