How to Reduce Unnecessary Blood Cultures: Construction and Validation of a Predictive Score for Blood Culture Positivity in Intensive Care

Study Overview
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Brief Summary
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Prospective observational cohort consisting of all adult patients admitted to participating critical care units (ICU and CCU) during the study period, with blood cultures collected as part of their care, and who did not express any objection to participating. For each patient, data will be collected prospectively for each blood culture set collected.

Official Title
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Comment Diminuer Les hémocultures Inutiles : Construction et Validation d'un Score prédictif de positivité Des hémocultures en réanimation.

Conditions
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Infection, Bacterial, Infection, Fungal, Bacteremia

Intervention / Treatment
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* Other: no intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male or female, age 18 years or older Patient admitted to an ICU or ICU patient with a blood culture sample as part of care Exclusion Criteria: Patient already included in this study during a previous hospitalisation Opposition expressed for participation in the study

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| learning database group<br>The results of blood cultures and the clinical elements of the patients in the first sample (1600 patients) will constitute the learning database. A supervised learning will be performed on these data in order to select a set of clinical elements allowing to define a predictive score of positive blood cultures | Other: no intervention<br>* no intervention<br>|
| validation database group<br>The score will be validated on the remaining sample (800 patients), independent of the first sample. Both samples will be constituted by randomization. | Other: no intervention<br>* no intervention<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Area under the ROC curve of the predictive performance of the score for predicting bacteremia or fungemia. |  | day 1- day 28 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Area under the ROC curve of the diagnostic performance of body temperature to predict bacteremia or fungemia; |  | day 1- day 28 | 
| Area under the ROC curve of the diagnostic performance of the Shapiro score for predicting bacteremia or fungemia; |  | day 1- day 28 | 
| Proportion of bacteremia or fungemia identified by blood cultures in patients on antibiotic therapy and broad-spectrum antibiotic therapy, and factors associated with these bacteremias or fungemias; |  | day 1- day 28 | 
| Comparison of the diagnostic performance of the score in predicting bacteremia or fungemia observed during the first 48 hours of hospitalization to later bacteremias; |  | 48 hours | 
| Descriptive study of the contribution of blood cultures, whatever their results, to the prescription of anti-infectives. |  | day 1- day 28 | 
| Efficiency of the new predictive score for blood culture positivity in Intensive Care, as compared with body temperature and Shapiro score, measured by two Incremental Cost-Effectiveness Ratios (ICER): ICER (incremental cost per additional well-detecte | A tree decision model will compare three strategies for predicting positive blood cultures: the new predictive score, body temperature and Shapiro score. Within-trial data will be used to define the model parameters. The model will consider the costs related to the implementation of the strategies, blood cultures, and potential delays in patient management. This will result in the estimation of the two ICERs. | less than 1 month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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intensive care unit, blood culture, prediction, score