1. Cost analysis of blood cultures
Richard Huynh
March 2013

2. Introduction 4-7% of blood cultures are positive.
False positives -> 50% increase in cost, 64% increase in length of stay.
Average of $ per culture
Goal is to identify indications for blood cultures
Cross sectional study of all patients currently on medicine team D to assess if orders were appropriate vs inappropriate

3. Indication
1 Major criteria included temperature > 39.5°C, indwelling vascular catheter, or clinical suspicion of endocarditis.
2 Minor criteria included temperature °C, age > 65 years, chills, vomiting, systolic blood pressure < 90 mm Hg, neutrophil% > 80, white blood cell count > 18, bands > 5%, platelets < 150, and creatinine > 2.0.

4. Results Admitting Dx Culture Criteria AKI Negative
age>65 and Cr>2
Hypoglycemia HD 2
38.3, age>65 and Cr>2
UTI
WBC>18, chills
N/V, Liver abscess
38.9, chills, vomiting
Weakness, HD 2
38.6, age>65
Obstructive jaundice
Cr>2, vomiting
Chest pain
Not ordered
Cr>2
DM foot ulcer
None
AMS
age >65
Fatigue
WBC>18
SOB

5. Of 11 patients: 55% (6) met criteria 36% (4) did not meet criteria
9% (1) appropriately not ordered

6. Conclusions 4/11 did not meet criteria Only 1/5 properly not ordered
Practice preventative medicine
Fever=culture
Confounding key factors
Physician dependent, ED vs IM
Sample size
Criteria may not be practical: wait until WBC>18? Subjective chills and vomiting?

7. Resources
Coburn B, Morris AM, Tomlinson G, Detsky AS. Does this adult patient with suspected bacteremia require blood cultures? JAMA Aug;308(5):
Shapiro NI, Wolfe RE, Wright SB, Moore R, Bates DW. Who needs a blood culture? a prospectively derived and validated prediction rule.J Emerg Med. 2008; 35(3):
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