A hospital-wide study of the impact of introducing a personal data assistant-augmented blood culture round

Abstract

Blood culture is the cornerstone of an established aetiological diagnosis of septicaemia. The automated blood culture systems used for this purpose have changed little in the last decade, and the clinical value of results depends on a variety of factors, including pre-and post-analytical variables. Growing scepticism over the value of blood culture results and pressure for the introduction of molecular detection systems have prompted a critical path analysis of pre-, peri-and post-analytical stages in the generation of positive blood culture results. The impact of a positive blood culture was studied in a teaching hospital for 12 months before and 12 months after the introduction of a microbiologist's blood culture round. Active culture reporting via a blood culture ward round was supported by a personal data assistant database of contemporaneous laboratory and clinical data. Hospital occupancy and death register records were subsequently obtained through the State Government data linkage project. There was no evidence that faster laboratory generation of positive blood culture results, faster reporting of results or direct clinical interaction with the patient's primary medical team reduced the risk of death in hospital. However, there was a threefold increase in the rate of death in hospital following a 1 day delay in collection of blood cultures after hospital admission (P50.0010). The overall duration of hospital stay for patients with a positive blood culture fell by 2.5 days compared with the previous 12 month period (P50.0003). The interval between the initial positive culture result and patient discharge fell by 2 days (P50.0010). This difference was attributed to shorter overall admissions and shorter intervals between positive cultures containing Gram-positive cocci and subsequent patient discharge (P50.0018). An increased mortality rate from community-acquired bacteraemic infections was associated with delayed culture collection, but not with a prolonged laboratory processing interval. Thus, the speed of conventional blood culture analysis and the form of clinical reporting have little direct effect on the clinical outcome of bacteraemia, but may contribute to a reduction in the length of hospital admission. Introduction of molecular identification tests, such as multiplex PCR methods, at the Gram-stain stage of blood culture is unlikely to affect the rate of death in hospital, but may reduce the length of hospital admission.

Blood cultures on internal medicine: utilization profile and clinical implications

“…This is particularly relevant in internal medicine wards, where multiple comorbidities, severe infectious or non-infectious diseases and complications during hospital stay are frequent. 4,11,12 Our positivity rate is slightly lower than in other series, which can be attributed to the several BC performed in patients with low-severity infection, namely patients who do not meet sepsis criteria. 13 It has been proposed that severity of infection may be the best predictor of positivity of BC, but the way to assess this remains controversial.…”

“…Recent papers suggest that overuse of BC may be responsible for prolonging hospital length of stay (LoS) and higher hospital costs, without relevant impact on mortality. 4 Direct utility of BC when measured by therapeutic changes based on its results is limited. According to a study by Corbo et al in 355 admissions for community acquired pneumonia, only in 5% of patients the antibiotic was changed based on BC results.…”

Timeliness and Accuracy of Reporting Preliminary Blood Culture Results: A College of American Pathologists Q-Probes Study of 65 Institutions

“…Previous studies have shown that timeliness of detecting bloodstream pathogens improves antimicrobial therapy, reduces costs, and decreases length of stay and patient mortality. [3][4][5][6][7][9][10][11] Timeliness and accuracy of preliminary blood culture results represent 2 important, evidence-based quality indicators that are closely linked to clinical outcomes.…”

“…Faster results reporting has been shown to be associated with lower mortality, 3 especially when combined with clinical consultation. 4,5 Other benefits of rapid reporting include improved selection of antimicrobial therapy, [6][7][8][9] lower overall health care costs, 10 and reduced length of stay. 8,11 Timely detection of bacteremia also facilitates initiation of rapid, direct methods for early identification and susceptibility testing.…”

Use of Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry Analysis for Rapid Confirmation of Burkholderia pseudomallei in Septicemic Melioidosis

“…1 It has been inferred from work on commoner bacteremic agents that faster identification of bacteria from blood cultures will result in faster defervescence and other benefits to septicemic patients. 2 In the case of melioidosis, an uncommon cause of septicemia in most centers, progression to multiple organ systems failure and death can be rapid. 3 Some patients who do not immediately die of septicemia can remain bacteremic for several days despite appropriate intravenous antimicrobial chemotherapy.…”