Intravenous catheter blood cultures: Utility and contamination

Objective. In pediatrics, blood cultures (BCs) are often drawn as intraveno us (IV) catheters are placed. This routine minimizes the number of painful and often difficult punctures a child must undergo but results in the disca rding of multiple BC bottles when these cultures are later determined to be unnecessary. If the contamination rate of BCs drawn through an indwelling IV did not exceed the contamination rate of BCs drawn at the time of IV pla cement, BCs could be drawn from the IV without subjecting the patient to an other venipuncture. This study was done to compare the contamination rates of BCs drawn by these two methods. Additionally, we sought to determine if the collection of two BCs enhances pathogen recovery. Methods. Prospective comparison of contamination and bacteremia rates of BC s drawn by two different methods: the first BC was drawn at the time of IV line placement and the second BC was drawn from the previously placed IV at a later time. Setting. Urban pediatric emergency department with an annual census of 40 0 00. Participants. One thousand five hundred sixty-four patients between the age s of 3 days and 22.1 years. The median age was 2.2 years. Sixty-four patien ts were excluded because we were unable to draw the second BC. Forty-six pe rcent of eligible patients (n = 690) were girls. Results. Fifty-seven (1.9%) of 3000 grew contaminants: 27 in the first and 30 in the second BC for contamination rates of 1.8% and 2.0%. Thirty-eight (1.3%) of 3000 BCs grew pathogens: 24 represent 12 patients with growth in two out of two cultures and 14 represent 14 patients with growth in one out of two cultures. Pathogen rates were 1.1% (16/1500) with one BC per patien t and 1.7% (22/1500) with two BCs per patient. Conclusions. There is no difference in the contamination rates of two BCs d rawn from the same site at two different times. The collection of two BCs p er patient may enhance pathogen recovery.