C-reactive Protein Information and Blood Cultures for Emergency Department Patients With Sepsis

A Multi-center Randomized Controlled Trial of C-reactive Protein Measurement on Ordering of Blood Cultures in Emergency Department Patients With Sepsis

Patients with sepsis (2 or more systemic inflammatory response syndrome criteria and suspected infection) assessed in the emergency department have blood cultures obtained to identify potential blood stream infections (BSI). Blood cultures are expensive, sometimes inaccurate, and only positive about 10% of the time in the emergency department.

This study evaluates the effect of physician knowledge of C-reactive protein (CRP) levels on ordering rates of blood cultures in emergency department patients with sepsis. All patients with sepsis will have CRP levels measured using a point-of-care device, prior to blood tests being ordered. Half of participants will have their CRP level available to the emergency physician and half will not. Blood culture ordering rate and safety outcomes will be compared between these two groups.

Sepsis, which is defined as the presence of a systemic inflammatory response syndrome (SIRS) in conjunction with a suspected or proven infection, is a significant cause of morbidity and mortality. It is an extremely common presentation in emergency departments. Most sepsis protocols and guidelines call for blood cultures to be obtained in patients with sepsis, in order to identify blood stream infections (BSI) which are usually caused by bacteria in the blood.

Blood cultures obtained in the emergency department are costly, subject to false positive results, and only positive about 10% of the time. Also, they rarely change patient management.

C-reactive protein (CRP) is an inflammatory marker that rises rapidly in the presence of bacterial infections. Because CRP rises as much as 100 times normal levels in the presence of bacterial infections, we have used it successfully to identify patients with sepsis who do not require a blood blood culture, we believe that physicians knowledge of CRP levels can help to guide their decision to order blood cultures.Patients with sepsis (2 or more SIRS criteria and presumed infection) will have their CRP levels measured using a point of care device (Alere Afinion AS100 Analyzer) prior to blood tests being ordered. Patients will be randomized to either have their CRP value shown to the attending physician or not. Rates of blood culture ordering and safety outcomes will then be compared between the two groups.

Inclusion Criteria:

• Emergency department patients with sepsis: Known or presumed infection and 2 or more SIRS criteria: heart rate > 90/minute; respiratory rate > 20/minute; Oral temperature ≥ 38◦ C or < 36◦ C; white blood cell count > 12,000 or < 4,000.
• Able to read and understand consent form in English
• Age 19 years or greater

Exclusion Criteria:

• Patients presenting with septic shock (systolic blood pressure < 90 mmHG)
• Patients at risk for endocarditis (previous episodes of endocarditis, injection drug use)
• Imuno-compromised patients: HIV positive and not on anti-retrovirals; active chemotherapy ; known immune disorder; on immune system modulating drugs, including corticosteroids.
• indwelling venous catheter (dialysis line, Hickman catheter)
• hospitalization in previous 2 weeks
• Surgical procedure in previous 2 weeks