Expert guidelines recommend getting blood cultures for all patients admitted with communityacquired pneumonia (CAP). Blood cultures have been used as a measure of quality of care. However, this diagnostic tool has a low yield of being positive in these patients and its utility in clinical management has been questioned in previous studies. The objective of the study is to determine whether positive blood culture results affect antibiotic therapy and patient outcomes in patients admitted for CAP.
We performed a retrospective cohort study utilizing the Community Acquired Pneumonia Organization (CAPO) database from January 2009 to December 2010. Patients who were 18 years or older, had a blood culture taken on day of admission, and a final diagnosis of community acquired pneumonia were included in the study. Patients classified as having healthcareassociated pneumonia or had suspicion of aspiration were excluded from the study. Main outcomes included change in antibiotic therapy, number of days on IV antibiotic therapy, and length of stay.
A total of 410 patients met study criteria. Blood cultures were positive in 36 of 410 (9%) patients. The most common cause of pneumonia in positive patients was Streptococcus pneumoniae. Following multiple regression analysis, positive blood cultures were found to be significantly associated with a longer length of stay (P = 0.007), and higher use of invasive ventilation (P = 0.001), aggressive fluids (P = 0.04), and vasopressors (P = 0.007). Positive blood culture results did not significantly impact a change in antibiotic therapy.
Positive blood cultures predict a longer length of stay and higher need for aggressive therapy for patients with CAP. However, positive blood cultures do not change antibiotic management and therefore are not of significant value in treating the patient.
Table 1Multiple regression analysis data on blood culture results effect on length of stay, outcomes and influence on antibiotic theraphy
To cite this abstract:Steinbrunner J, Castaneros L, Blatt S. Blood Cultures in Community Acquired Pneumonia: Influence on Antibiotic Therapy and Patient Outcomes. Abstract published at Hospital Medicine 2012, April 1-4, San Diego, Calif. Abstract 97628. Journal of Hospital Medicine. 2012; 7 (suppl 2). https://www.shmabstracts.com/abstract/blood-cultures-in-community-acquired-pneumonia-influence-on-antibiotic-therapy-and-patient-outcomes/. Accessed December 6, 2019.