CLABSI Culprits in Critical Care: Looking Beyond the Expected Portal of Entry

The doctor is puncturing the left radial artery to get an arterial blood pressure line before the operation.

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Patient safety is at the forefront of everything the infection preventionist (IP) is involved with. In this era of value-based purchasing (VBP) and health care transparency, it is no longer acceptable to be good or very good. The expectation is demonstrated excellence. The high morbidity and mortality rates resulting from central line–associated bloodstream infections (CLABSIs) make this a critical VBP infection metric set forth by the Centers for Medicare & Medicaid Services.

Critically ill patients, one of the most vulnerable patient groups, often have 1 or more central venous catheters (CVCs) in place and may also have an arterial line and peripheral lines. When a patient has a CVC and an unexplained BSI, the infection is usually attributed to the CVC. But what if the culprit is not the central line but one of the other access points?

Care and Maintenance of Vascular Accesses

When assessing CLABSI prevention, the IP reviews the CLABSI prevention bundles of care for insertion and maintenance to ensure that these practices are incorporated into policy and practice. Much emphasis has been placed on this bundled approach of care with demonstrated success in CLABSI reduction.¹ The same level of attention should also be directed at intra-arterial catheters (IACs) and peripheral intravenous (PIV) catheters.

Without the same level of heightened awareness of care bundles of other vascular catheter infection prevention practices, these additional devices can offer pathogens a portal of entry into the vascular system. Should this occur concurrently with a CVC and without evidence of another infectious source, the BSI will be attributed to the central line. In this scenario, the true CLABSI culprit evades detection.

Contributing to this phenomenon is the use of the CLABSI surveillance definition instead of the more stringent and less practical catheter-related BSI (CRBSI) clinical definition. CRBSI criteria require quantitative cultures of the CVC catheter tip and peripheral blood cultures that produce positive results identifying the same organism within 2 hours. “The incidence of arterial CRBSI has been shown to represent a significant health care burden, although it is commonly underestimated in clinical practice.”² This underestimation may be relative to the lack of universal availability of laboratory resources for qualitative results.

Table. Drawing Blood From Open and Closed Arterial Line Systems⁸

ABG, arterial blood gases; N/A, not applicable.

Literature Review

A literature review has identified that arterial and peripheral lines are often overlooked sources of BSIs. Buetti et al have identified in their multisocietal expert guidance document that these vascular accesses are not included in surveillance systems despite the increased risk of BSI and suggest that these devices could be included in infection surveillance systems.³ For their retrospective cohort study, Barros, Enfield, and Kadi identified IAC insertion practice variations and noted that reported rates of bacteremia with IACs were higher than observed with PIVs but lower than with CVCs.⁴ Their study concluded that IAC use actually demonstrated a higher associated risk of hospital-onset bacteremia than the risk with CVCs.

Figure 1, Examples of Open and Closed Systems

(Images courtesy of authors)

The study authors recognize that IAC-associated bacteremia will meet CLABSI criteria and “suggest that IACs be placed with similar precautions to CVCs.”⁴ The lack of consistent adherence to CDC-recommended practices for the care of IAC lines is also recognized in the narrative review of IAC infection risk by Card et al, and the incidence of these infections is underestimated.² The Infusion Nursing Society guidelines “recognize the risk of an arterial catheter as a potential source of CLABSI.”^5,6

At the Association for Professionals in Infection Control and Epidemiology 2024 Annual Conference & Exposition, a poster presentation demonstrated a significant reduction in CLABSI rates when the use of closed Arterial-line systems (A-line) systems was implemented in phase 2 of their CLABSI reduction study. The poster abstract article is now published in the American Journal of Infection Control.⁷

Open vs Closed Arterial Line Systems

Arterial lines are inserted for blood pressure monitoring and easy access for blood studies. Nurses access them for laboratory blood specimens, and respiratory therapists access them for arterial blood gases. Both open and closed systems are available, with variations by manufacturer (Figure 1). A closed system is designed to prevent the entry of infectious organisms into the body. Closed device systems such as urinary catheters with an intact seal and closed ventilator suctioning catheters are other closed systems designed to prevent infection. The same closed system concept applies to arterial catheters.

A review of Elsevier⁸ showed the procedural steps of drawing blood from both an open and closed arterial line system; these have been summarized and condensed into a comparison chart (Table). The chart does not include all the steps but concentrates on the differences the IP might be interested in. Please note that manufacturer-specific steps should be considered.

When reviewing the chart, it should be noted that more manipulation may be required in the open system, both when drawing off the discard and again when flushing the port. In the closed system, the line does not need to be accessed additionally for those steps. The system should be examined for any residual blood present after completing the blood draw, whether by a nurse or respiratory therapist. At times, there may be residual blood in the stopcock port in an open system, which could be a medium for pathogen adherence should the stopcock get contaminated. If present, it should be flushed until clear.

One drawback to the closed system could be the difficulty of removing dried blood from the blood sampling port. This can be avoided by immediately removing blood from the sampling port with an alcohol pad. Also, if the hospital practice is to use alcohol-impregnated caps for the sampling port, it should be determined whether the sampling port can accommodate an alcohol-impregnated cap for the system used.

Figure 2. Component Examples Used for Drawing Blood Specimens Drom Open and Closed IAC Systems

(Images courtesy of Authors)

Other Considerations

It is critical to ensure that all health care personnel who access the IAC have had training specific to the type of IAC in use. PIVs may also contribute to BSIs. The number of PIVs in use should always be kept to a minimum and not left in “just in case.” Those that are needed should be assessed carefully per the hospital’s policy. Comprehensive policies and education should include strict insertion and maintenance bundles of care for all vascular access devices for CLABSI prevention.

Conclusion

Central lines and other intravascular devices can save lives or can contribute to sepsis and death. Their use and maintenance should be meticulous. Access points to the bloodstream must be minimized, and those needed should be safeguarded from infection. This way, the patient can receive the care needed for a safe journey back to health.

References

1. Gupta P, Thomas M, Patel A, et al. Bundle approach used to achieve zero central line–associated bloodstream infections in an adult coronary intensive care unit. BMJ Open Qual. 2021;10(1):e001200. doi:10.1136/bmjoq-2020-001200

2. Card S, Piersa A, Kaplon A, et al. Infectious risk of arterial lines: a narrative review. J Cardiothorac Vasc Anesth. 2023;37(10):2050-2056. doi:10.1053/j.jvca.2023.06.037

3. Buetti N, Marschall J, Drees M, et al. Strategies to prevent central line–associated bloodstream infections in acute-care hospitals: 2022 update. Infect Control Hosp Epidemiol. 2022;43(5), 553-569. doi:10.1017/ice.2022.87

4. Barros AJ, Enfield KB, Kadl A. Intraarterial catheter use is associated with increased risk of hospital onset bacteremia: a retrospective cohort study. Chest. 2021;156(6):2321-2324. doi:10.1016/j.chest.2021.01.038

5. Nickel B, Gorski L, Kleidon T, et al. Infusion therapy standards of practice, 9th edition. J Infus Nurs. 2024;47(1S suppl 1):S1-S285. doi:10.1097/NAN.0000000000000532

6. Nickel B. Hiding in plain sight: Peripheral intravenous catheter infections. Crit Care Nurse. 2020;40(5):57-66. doi:10.4037/ccn2020439

7. Ray LR, Miller K. Closed systems: are conventional arterial line monitoring and sampling systems contributing to central line associated bloodstream infections (CLABSI(s)? Am J Infect Control. 2024;52(suppl 6):S60. doi:10.1016/j.ajic.2024.04.108

8. Elsevier Clinical Skills. Blood Specimen Collection: Arterial Catheter CE/NCPD. Accessed September 12, 2024. https://elsevierperformancemanager.com