Is it okay to use a port that has been cultured the same day?

Using a Port That Has Been Cultured the Same Day

It is not recommended to use a port that has been cultured the same day due to the risk of introducing pathogens into the bloodstream while culture results are pending. 1

Rationale for Avoiding Same-Day Port Use After Culturing

When a port is cultured, the procedure involves accessing the port reservoir to obtain samples for microbiological analysis. This process creates several potential risks:

1. Disruption of potential biofilm: Accessing a potentially infected port may dislodge bacteria from biofilms within the port reservoir or catheter lumen 1

2. Pending culture results: Culture results typically take 24-48 hours to return, and using a port before knowing if it's infected could lead to:

   • Introduction of pathogens into the bloodstream
   • Systemic infection or sepsis
   • Compromised treatment outcomes

3. Diagnostic integrity: Using the port after culturing but before results are available may interfere with the accuracy of culture results 2

When Port Culturing Is Performed

Port culturing is typically done when there is suspicion of catheter-related bloodstream infection (CRBSI). According to the Infectious Diseases Society of America guidelines, port culturing should be performed in the following circumstances:

• When a port is removed due to suspected infection
• Not as a routine procedure without clinical indication 1

For venous access subcutaneous ports specifically, the guidelines recommend:

• Sending the port to the microbiology laboratory for qualitative culture of the port reservoir contents
• Culturing the catheter tip as well 1

Diagnostic Process for Suspected Port Infection

If port-related infection is suspected, the proper diagnostic approach includes:

1. Before port removal:

   • Obtain paired blood cultures (one from the port and one from a peripheral vein) 1
   • Properly label samples to indicate their source 1
   • Ensure proper skin disinfection with chlorhexidine gluconate in alcohol, tincture of iodine, or alcoholic chlorhexidine (>0.5%) 1

2. If port removal is necessary:

   • Culture the catheter tip using semiquantitative (roll-plate) or quantitative (sonication) methods 1
   • Culture the material inside the port reservoir, which is highly predictive of infection 1, 3

Risk Factors for Port Infections

Several factors increase the risk of port infections:

• Frequent access to the port (≥3 times per day over a 10-day period) increases infection risk 8-fold 4
• Use of the port for total parenteral nutrition significantly increases the risk of Candida infections 5
• Improper aseptic technique during port access 2

Common Pitfalls to Avoid

1. Not obtaining cultures before starting antibiotics: This significantly reduces diagnostic sensitivity 2

2. Poor aseptic technique: Failure to properly disinfect the skin or port hub before access increases contamination risk 2

3. Immediate use after suspected infection: Using a port that has been cultured for suspected infection before confirming it is not infected can lead to systemic infection 6

4. Improper labeling of samples: Failure to correctly label catheter vs. peripheral samples prevents proper interpretation of results 2

While one small study suggested that accessing a newly placed port immediately after placement did not significantly increase infection risk 7, this does not apply to ports that have been cultured for suspected infection.

In conclusion, the safest approach is to avoid using a port that has been cultured the same day until culture results confirm the absence of infection, especially when the culturing was performed due to suspicion of infection.