An evidence-based surveillance tool to identify and report catheter/cannula bloodstream infection in patients receiving parenteral nutrition

Objective: Catheter/cannula-bloodstream infection (CBI) has been proposed as a marker of the quality of care provided to patients receiving parenteral nutrition (PN). However, surveillance criteria for CBI are variable, inconsistent, and sometimes confusing and impractical. Surveillance criteria were developed to simply and accurately demonstrate the presence or absence of CBI. The aim of this study was to establish a simple and valid surveillance tool, with consideration of changes in vital signs, to identify CBI in patients receiving PN.

Methods: Adult (≥18 y) inpatients prescribed PN at a single large teaching hospital were recruited between October 11, 2017 and November 16, 2018. Common clinical and laboratory criteria, including blood culture, associated with 100 consecutive PN episodes associated with suspected CBI were examined for potential predictive markers of CBI. Using binary logistic regression, criteria were incorporated into an instrument that was validated against a reference classification of CBI established by an expert multidisciplinary group.

Results: The reference classification comprised 12 PN episodes with CBI and 88 without. Abnormal vital signs did not significantly predict CBI, but resolution of fever (≥38°C) and low systolic blood pressure (<100 mm Hg) in response to a specific treatment for CBI (line removal/antibiotics) did. Two other criteria were also significant predictors: positive blood culture; and absence of an alternative source that could explain the septic episode other than the catheter/cannula supplying PN. These two criteria together with a positive response to treatment (temperature and/or blood pressure, incorporated into a single binary variable), resulted in 100% correct CBI classification (100% sensitivity, 100% specificity, and 1.000 area under the curve in receiver operating characteristic analysis). All criteria could be retrospectively extracted from the medical records of all PN episodes.

Conclusion: A CBI tool shows promise as a surveillance instrument for benchmarking and interinstitutional comparisons of the care received by hospitalized patients given PN.