What are the CLABSI (Central Line-Associated Bloodstream Infection) attribution rules for boarding ICU (Intensive Care Unit) patients in the CDC (Centers for Disease Control and Prevention)/NHSN (National Healthcare Safety Network) guidelines?

CLABSI Attribution Rules for Boarding ICU Patients

The CDC/NHSN defines CLABSI as a primary bloodstream infection in a patient who had a central line within 48 hours before infection development, and attribution is based on the location where the patient is physically present at the time of the event, not where the patient is "supposed to be" or where they receive their primary care. 1

Core Attribution Principle: Physical Location at Time of Event

For boarding ICU patients (those physically located in non-ICU areas while awaiting ICU bed availability), the CLABSI is attributed to the physical location where the patient is at the time the infection criteria are met, regardless of their intended or "boarding" status. 1

The 48-Hour Window Rule

• A BSI is attributed to a central line if the line was in use during the 48-hour period before development of the infection. 1
• If the time interval between onset of infection and device use exceeds 48 hours, there must be compelling evidence that the infection is related to the central line. 1, 2
• Day 1 of infection is considered the first day on which negative blood culture results are obtained after initiating appropriate therapy. 3

Practical Algorithm for Attribution

Step 1: Determine Physical Location

• Identify where the patient is physically located when blood culture collection occurs or when infection criteria are first met. 1
• This physical location receives the CLABSI attribution, even if the patient is "boarding" and awaiting transfer. 1

Step 2: Verify Central Line Presence

• Confirm a central line (vascular access device terminating at or close to the heart or great vessels) was present within 48 hours before BSI development. 1, 2
• Umbilical artery or vein catheters are considered central lines for attribution purposes. 1

Step 3: Exclude Secondary Sources

• Ensure the BSI is not related to an infection at another site (must be a primary BSI). 1, 2
• Review for evidence of other infection sources that could explain the positive blood cultures. 3

Common Pitfalls in Boarding Patient Attribution

Pitfall 1: Attributing to "Intended" Location

• Do not attribute the CLABSI to the ICU simply because the patient is "boarding" and awaiting ICU admission. 1
• Attribution follows physical location, not clinical service or intended destination. 1

Pitfall 2: Timing Confusion

• The critical timeframe is the 48 hours BEFORE infection development, not after. 1, 2
• If a patient boards in the emergency department for 36 hours with a central line, then develops CLABSI criteria while still in the ED, this is attributed to the ED, not the ICU. 1

Pitfall 3: Transfer Within 48 Hours

• If a patient transfers locations after blood cultures are drawn but before infection criteria are fully met, attribution goes to the location where the patient was when the infection criteria were completed. 1

Special Considerations for High-Risk Boarding Populations

Hematologic Malignancy Patients

• Patients with hematologic malignancies represent up to 67% of non-ICU CLABSI cases and have significantly higher mortality (27.3% in some cohorts). 4, 5
• Neutropenia at the time of CLABSI occurs in 91.8% of patients with malignant hematologic diagnoses. 4
• These patients boarding in non-ICU settings have CLABSI rates significantly higher than concurrent ICU rates (2.1 vs 1.5 per 1,000 catheter-days). 5

Device-Specific Risk Factors

• Peripherally inserted central catheters (PICC lines) account for approximately 50% of CLABSIs in non-ICU settings. 4
• Tunneled lines are present in 76% of non-ICU CLABSI events. 5
• Multilumen catheters and use of more than one central venous catheter per case increase CLABSI risk. 6

Duration and Location Impact

Length of Stay Before CLABSI

• The mean length of hospital stay prior to CLABSI in non-ICU settings is 16 days, nearly 3 times the hospital-wide non-ICU length of stay. 4
• Catheterization duration beyond 1 week significantly increases CLABSI risk. 3, 6

Site-Specific Risk

• Femoral and jugular insertion sites have higher infection rates than subclavian sites, regardless of boarding status. 2, 3
• This risk profile persists even when patients are boarding in non-traditional locations. 2, 3

Documentation Requirements for Attribution

Essential Elements

• Document the exact physical location of the patient when blood cultures were obtained. 1
• Record the date and time of central line insertion and removal (if applicable). 1
• Note whether the patient was boarding and awaiting transfer at the time of infection criteria fulfillment. 1

Quality Improvement Implications

• Non-ICU CLABSI rates may be artificially elevated in units that frequently board ICU patients, as these patients carry higher baseline risk. 4, 5
• The overall device utilization ratio in non-ICU settings is typically 0.27, but this varies significantly with boarding patient volume. 5
• Mortality associated with non-ICU CLABSI is 18.3% overall and reaches 23-27.3% in high-risk subgroups. 4, 5