Specimen Requirements

Blood cultures should be drawn prior to initiation of antimicrobial therapy. When blood cultures are ordered, 2 sets should be drawn from separate peripheral sites. Orders for blood cultures where subacute endocarditis is suspected, must have a diagnosis of endocarditis noted on the request form. Three blood cultures should be drawn at 1-hour intervals if this is the suspected diagnosis.

Culture specimens are drawn prior to any other specimen draws with same venipuncture site (exceptions:  ionized calcium, venous pH). Volume of blood is critical because concentration of organisms in most cases of bacteremia is low. Therefore for adults, 2 sets with a volume of 20 mL should be collected.

Preparation of Patient and Collection of Blood

1. Vigorously cleanse venipuncture site using a ChloraPrep® scrub, cleaning in a back and forth motion, for 30 seconds.

2. Allow site to dry. Do not touch site after preparation and prior to venipuncture.

3. Remove plastic cap and disinfect rubber top of blood culture bottles with alcohol and allow to dry.

4. Apply tourniquet, insert needle into vein, and withdraw blood. Do not change needles before injecting blood into culture bottles.

5. Aseptically inject the volume in each bottle:

Regular Blood Culture bottles  Aerobic 8 mL to 10 mL (maximum:  10 mL)

Regular Blood Culture Anaerobic 8 mL to 10 mL (maximum:  10 mL)

Pediatric Blood Culture bottles: 1 mL to 4 mL (maximum:  4 mL)

Mix well to avoid clotting.

6. Label bottles with patient’s name (first and last), MR# or DOB, date and actual time of draw, and type of specimen.

7. Maintain sterility and forward promptly at ambient temperature only.

Note:  1. Do not use iodine on tops (septa) of blood culture bottles.

2. Collection can be performed by needle and syringe or by using a butterfly with an adaptor for direct inoculation into bottle.

Volume Requirements

Regular Blood Culture bottles, Aerobic 8-10 mL (maximum volume:  10 mL) 

Regular Blood Culture bottles, Anaerobic 8-10 mL (maximum volume:  10 mL) 

Pediatric Blood Culture bottles, 1-4mL (maximum volume:  4 mL)