Test Directory

Blood Cultures

Containers - Adult

Blood Culture Set - Adult
Volume Range

Up to 10ml (8-10 ml is optimal). Do not overfill.

Containers - Child

Paediatric Blood Culture Bottle
Volume Range

Up to 4 ml. Do not overfill.

Laboratory Site

51 Little France Crescent
Old Dalkeith Road
EH16 4SA
Telephone (Bacteriology): 0131 242 6021 OOH Bleep 2900
Howden Road West
West Lothian
EH54 6PP
Telephone (Bacteriology): 01506 52 3075 OOH contact RIE

Transport arrangements

Transport as soon as is practical. Best organism recovery is when collection of blood cultures to incubation is less than 4 hours. Can go in pneumatic tube system. (NB Mycobacterial Blood Cultures - in glass bottles cannot go in the pneumatic tube system)

Sample storage arrangements

Samples need to reach the lab incubators within four hours of being collected to be most useful. If there's a delay in transporting to the lab at RIE, store at room temperature. If out of hours at SJH ( 0900-1700 Mon to Fri, 0900-1600 Sat/Sun) store in the 37°C out of hours incubator. Don't refrigerate samples.

Special instructions for collection

Venous blood, arterial blood and sterile fluids can all be inoculated. Don't take off barcode stickers from the bottles.

See Blood culture skin preparation and aseptic sample collection procedure

Fill bottles optimally with 10mls of blood in each; overfilling bottles can lead to false positive results. Underfilling bottles reduces the chance of recovering bacteria, and false negatives. There is a direct relationship between blood volume and bacteria recovered, with approximately a 3% increase in yield per mL of blood cultured. If you haven't got enough blood, prioritise the aerobic (blue) bottle as most organisms we recover are aerobic.

Always sample a peripheral vein if possible, but if sampling an intravascular line when a line infection is suspected, sample all lumens and ensure labelled as cultures from a line. If inoculating blood culture bottles using a butterfly collection set and direct draw adapter cap, inoculate the aerobic bottle (blue) first and then the anaerobic bottle (red) so that any oxygen trapped in the tubing will not be transferred to the anaerobic bottle. If filling with a syringe, fill the anaerobic (red) bottle first.

How to request

Via Trak (Blood Culture Ix - ADULT ONLY). The same Trak number goes on each bottle of the set; you need to print two labels from the same request if labelling a pair of adult blood culture bottles. 


Blood cultures can be taken, and sent to the lab, at any time. 

Anticipated turnaround

Primary report after 48 hours of receipt in the lab. Total incubation 5 days. 

What happens if the result is positive or abnormal

Telephoned by microbiologist.

General additional information

This test is useful for:

Patients with fever or where there is a suspicion of serious infection. Identifies blood stream infections caused by bacteria or fungi. Can also be used for small volumes of sterile fluids (e.g. Ascites, joint fluids, peritoneal dialysis fluids etc.) to aid the recovery of fastidious organisms. Collect specimens before antimicrobial therapy where possible

To help with lab risk assessment, please highlight any history of foreign travel or animal exposure in the clinical details.