Blood Culture Collection: Prep, Bottles, Volumes, Order
Blood cultures are drawn first in the order of draw, after an antiseptic skin prep that is left to dry; disinfect each bottle top, fill to the stated volume (8 to 10 mL per adult bottle) and never refrigerate.
Skin and bottle preparation
- Check that bottles are in date and undamaged; do not use a bottle that looks discoloured or contaminated (Eastern Health procedure).
- Remove the plastic caps (the septum underneath is not sterile) and disinfect each rubber septum with 70% isopropyl alcohol, a separate wipe for each bottle (Merck: scrub 30 seconds), and let it air-dry (Merck Manual; Ombelet 2019; Doern 2019).
- Clean the skin with chlorhexidine (usually chlorhexidine in alcohol) or 2% iodine tincture, applied as the product directs, and let it air-dry completely (IDSA/ASM 2024). Times differ by source: IDSA/ASM says these need about 30 seconds to act and Doern allows at least 30 seconds for drying; Merck and an example lab procedure (Eastern Health) wait 1 minute for chlorhexidine. Follow your facility's procedure.
- Infants under 2 months: IDSA/ASM does not recommend chlorhexidine and recommends povidone-iodine followed by alcohol (Merck: use chlorhexidine with caution, risk of irritation or chemical burns). Follow facility policy (IDSA/ASM 2024; Merck Manual).
- Do not touch or re-palpate the cleaned site; if it is touched, clean it again (Eastern Health procedure; Merck Manual).
- Wear gloves and use aseptic technique; sterile gloves are listed for blood cultures and are needed if the site must be re-palpated (Merck Manual; Korean guideline 2025; Doern 2019).
Preview only. The full sheet also covers: Volumes and number of sets; Paediatric volumes (weight-based example); Order and handling.
Sources
- How To Do Venous Blood Sampling (Merck Manual Professional Edition, procedure page) · Merck & Co., Inc. (Merck Manuals)
- Ombelet S, et al. Best Practices of Blood Cultures in Low- and Middle-Income Countries. Front Med 2019;6:131 (PMC6591475) · Frontiers in Medicine via PubMed Central
- Lamy B, et al. How to Optimize the Use of Blood Cultures for the Diagnosis of Bloodstream Infections? A State-of-the Art. Front Microbiol 2016;7:697 (PMC4863885) · Frontiers in Microbiology via PubMed Central
- Sautter RL, et al. American Society for Microbiology evidence-based laboratory medicine practice guidelines to reduce blood culture contamination rates: a systematic review and meta-analysis. Clin Microbiol Rev 2024 (PMC11629619) · American Society for Microbiology via PubMed Central
- Collection of Blood Culture Specimens, SOP 6972 v4.0 (effective 2021-05-13), including the paediatric maximum blood draw chart; Eastern Health Laboratory Medicine, Newfoundland and Labrador (institutional procedure, used as an example) · Eastern Health Laboratory Medicine
- Chang J, et al. Standards and Practice Guidelines for Venous Blood Collection: Consensus Recommendations from the Korean Society for Laboratory Medicine. Ann Lab Med 2025;45(4):343-357 (PMC12187494) · Annals of Laboratory Medicine via PubMed Central
- Order of Blood Draw Tubes and Additives (CLSI blog summary of GP41, Collection of Diagnostic Venous Blood Specimens; GP41-Ed7 was replaced by CLSI PRE02-Ed8, 2025) · Clinical and Laboratory Standards Institute
- WHO Guidelines on Drawing Blood: Best Practices in Phlebotomy (2010); official WHO IRIS PDF, also published as NCBI Bookshelf NBK138650 · World Health Organization
- Miller JM, et al. Guide to Utilization of the Microbiology Laboratory for Diagnosis of Infectious Diseases: 2024 Update by the Infectious Diseases Society of America (IDSA) and the American Society for Microbiology (ASM). Clin Infect Dis 2024 (doi:10.1093/cid/ciae104) · Infectious Diseases Society of America / American Society for Microbiology (Oxford University Press)
- Doern GV, Carroll KC, Diekema DJ, et al. Practical Guidance for Clinical Microbiology Laboratories: A Comprehensive Update on the Problem of Blood Culture Contamination and a Discussion of Methods for Addressing the Problem. Clin Microbiol Rev 2019;33(1):e00009-19 (PMC6822992) · American Society for Microbiology via PubMed Central
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