CLABSI in Hematology and Oncology: Progress Toward Zero

For some time, any bloodstream infection (BSI) in a patient with a central venous catheter was considered a central line-associated bloodstream infection (CLABSI). In 2013, refined definitions enabled a distinction between a CLABSI directly related to the central venous catheter versus one arising from other means, such as a mucosal barrier injury (MBI). Clinician-researchers at Nationwide Children’s have now published the first-known investigation of MBI and non-MBI CLABSI risk factors and outcomes across the medical care continuum in pediatric hematology and oncology patients. They discovered a high risk for negative outcomes of both such infections in ambulatory patients. They also identified a lack of clear opportunities to move the needle on MBI infections, which have not responded to preventative and maintenance care bundles implemented to reduce CLABSI.

Bloodstream infections (BSI) in children with a central venous catheter can be particularly dangerous to those with compromised immune systems, such as the hematology, oncology and hematopoietic cell transplantation (HCT) patients included in the 5-year retrospective data review, published this January in the Journal of Pediatric Hematology/Oncology.

“When our patients have a central line and a compromised immune system, they are increasingly predisposed to a bloodstream infection,” says Jeff Auletta, MD, director of the Blood and Marrow Transplant (BMT) Program and the Host Defense Program at Nationwide Children’s, and senior author on the publication. “When they also have a mucosal barrier injury, it’s three hits, and their bloodstream infection risk becomes even higher. The morbidity and mortality associated with these infections are significant, and such infections drive up healthcare costs. Therefore, we focus a lot of effort into CLABSI reduction.”

To help prevent CLABSIs, clinical care teams at Nationwide Children’s use a CLABSI care bundle, designed to reduce the introduction of bacteria into the bloodstream via the central venous catheter. Nationally, use of such bundles has resulted in a 28% reduction in inpatient CLABSI rates in pediatric hematology and oncology patients, and Nationwide Children’s overall CLABSI rates are currently similar to or better than national averages.

Despite >95% adherence to the Nationwide Children’s CLABSI bundle — which has several layers of preventive actions beyond those suggested by advisory groups — 14.6% (118) of 808 children experienced at least one BSI during the study period (2012-2016). Overall, BSIs in hospitalized patients were higher than among outpatients (2.2 vs 0.27 infection days per 1000 central line days), despite ambulatory patients having 10 times as many days at risk for a CLABSI.

In general, infections were most likely to occur in children with central venous catheters placed more than once, as well as in children with tunneled port catheters and peripherally inserted central catheters (PICCs) rather than permanent ports. Interestingly, nearly half (42%) of the 159 total infection events were MBI infections and hospitalized patients were at three times the risk of MBI infection as ambulatory patients.

Despite the lower overall risk for infection among ambulatory patients, risk of shock within 48 hours (58% for MBI and 30% for non-MBI cases), neutropenia (100% for MBI and 41% for non-MBI), and transfer to the pediatric intensive care unit (PICU) (28% for MBI and 9% for non-MBI cases) among outpatients occurred at rates higher than expected. According to the research team, these findings suggest the need for additional monitoring of these children to reduce negative outcomes and enable earlier identification of warning signs.

“It is critical to recognize how many outpatients needed to go to the PICU and developed shock symptoms from having an infection in the home setting,” says Mindy Bibart, MSN, RN, director of nursing for Hematology/Oncology/BMT at Nationwide Children’s and co-lead author on the paper. “This supports the need for new quality improvement initiatives, such as getting antibiotics in these children as soon as they get to the emergency department.”

While some of the study’s findings have likely explanations — for example, parents may be less likely to notice early symptoms in their home-based child — others give the researchers pause.

“The bundles we put in place to prevent non-MBI CLABSI don’t have much effect on preventing MBI CLABSI,” says Monica Ardura, DO, MSCS, medical director of the Host Defense Program and an infectious disease specialist at Nationwide Children’s, and co-lead author on the publication. “By looking at our patients across the care continuum over this amount of time, we tried find possible risk factors for MBI CLABSI that we could change somehow to decrease it. Fortunately and unfortunately, our rates were so low we didn’t have enough cases. It is really a knowledge gap in the literature and in clinical practice: we don’t know the modifiable risk factors for MBI CLABSI to know how we can best prevent them in our patients most at risk.”

The team hopes to collaborate with other centers in order to obtain sufficient data to improve MBI and non-MBI CLABSI prevention and risk reduction. They are also working on additional CLABSI educational efforts, bundle implementation strategies, and quality improvement practices to share in an upcoming manuscript regarding best practices in CLABSI prevention.

“Without the baseline data it’s hard to know if you’re making a difference,” says Dr. Auletta. “We used this to take a deeper look at our performance, and have tried to find interventions to move the needle even more.”

References:

1. Ardura MI, Bibart MJ, Mayer LC, Guinipero T, Stanek J, Olshefski RS, Auletta JJ. Impact of a best practice prevention bundle on central line-associated bloodstream infection (CLABSI) rates and outcomes in pediatric hematology, oncology, and hematopoietic cell transplantation patients in inpatient and ambulatory settings. Journal of Pediatric Hematology Oncology. 2021 Jan;43(1):e64-e72.
2. CE Dandoy, MI Ardura, GA Papanicolaou, JJ Auletta. Bacterial bloodstream infections in the allogeneic hematopoietic cell transplant patient: new considerations for a persistent nemesis. Bone Marrow Transplantation. 2017;52:1091–1106.

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