Chapter 55. Blood Culturing

Introduction

Fever and sepsis work-ups are a routine part of intensive care unit (ICU) care and particularly challenging due to indwelling catheters, and the lack of veins in chronically critically ill patients.

Definitions and Terms

• ▪  Aerobic media: Culture media specifically designed to support the growth of aerobic media (Figure 55-1)
• ▪  Anaerobic media: Culture media specifically designed to support the growth of anaerobic organisms (Figure 55-1)

Techniques

• ▪  A peripheral vein is identified and the skin prepped with a topical disinfectant such as chlorhexidine or povidine-iodine (Figure 55-2).
• ▪  The operator should wear sterile gloves if a skin-touch technique is to be used, nonsterile gloves may be used with a no-touch technique (Figure 55-3).
• ▪  At least 20 cc of blood should be withdrawn from the site if feasible, and 10 cc injected into both the aerobic and anaerobic media (Figure 55-4).

Clinical Pearls and Pitfalls

• Many experts recommend against the practice of drawing blood cultures through existing, indwelling catheters, believing that catheter contamination without true patient infection may lead to false-positive results.

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