Presented at the Neonatal Society 2012 Spring Meeting.

Ponnusamy V¹, Venkatesh V², Curley A², Perperoglou A³, Brown N⁴, Tremlett C⁵,
Clarke P¹

¹ Neonatal Intensive Care Unit, Norfolk and Norwich University Hospitals NHS Foundation Trust, Norwich, UK
² Neonatal Intensive Care Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
³ Norwich Medical School, University of East Anglia, Norwich, UK
⁴ Clinical Microbiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
⁵ Department of Microbiology, Norfolk and Norwich University Hospitals NHS Foundation Trust, Norwich, UK

Background: Percutaneous central venous catheters (PCVCs) are routinely inserted using aseptic technique after local skin disinfection. Effective topical skin disinfection regimes should abolish skin bacteria at line insertion site and limit the risk of associated catheter-related sepsis (CRS). We aimed to examine the relationship between bacteriology of insertion-site skin swabs taken at line removal and line colonisation/CRS.

Methods: Prospective study with ethics approval over 14 months in 2 tertiary neonatal units. For each PCVC removed, a skin swab taken from the insertion site and three separate PCVC segments were sent for bacteriological culture. For clinically-septic neonates a peripheral blood culture was additionally obtained. PCVC colonisation was defined as a positive growth in any PCVC segment from a well neonate. Definite CRS was defined as positive growths with the same organism in both any PCVC segment and the blood culture from a clinically-septic neonate.

Results: 39 (21%) skin swabs were culture-positive from 187 PCVC removals. The table shows culture-positive skin swabs according to subgroups of neonates:

*one had ‘mixed growth’ and another ‘skin flora‘
N/A – Not applicable
†Colonised vs. sterile, P<0.0001
‡Definite CRS vs. clinical sepsis, P<0.01

Conclusion: Positive insertion site skin swabs correlate strongly with both PCVC-colonisation and definite CRS. Despite topical antisepsis, PCVC colonisation and subsequent CRS appear to occur via the extraluminal mode of spread of skin bacteria from line insertion site. Current methods and/or agents of topical skin disinfection appear inadequate for preventing this mode of bacterial spread in neonates.

Corresponding author: drnila@doctors.org.uk