Evaluation of Skin Colonisation And Placement of vascular access device Exit sites (ESCAPE Study)
Background: Skin microorganisms may contribute to the development of vascular access device (VAD) infections.
Baseline skin microorganism type and quantity vary between body sites, yet there is little evidence to inform choice of
VAD site selection.
Objective: To compare microorganisms present at different body sites used for VAD insertions and understand the
effect of transparent dressings on skin microflora.
Methods: The ESCAPE observational study consisted of three phases: (1) skin swabs of four sites (mid-neck, base neck,
chest, upper arm) from 48 hospital patients; (2) skin swabs of five body sites (mid-neck, base neck, chest, upper arm, lower
arm) from 10 healthy volunteers; and (3) paired skin swabs (n = 72) under and outside of transparent dressings from
36 hospital patients (16 mid/base neck, 10 chest, upper arm). Specimens were cultured for 72 h, species identified and
colony-forming units (CFU) counted. Ordinal logistic regression compared CFU categories between variables of interest.
Results: The chest and upper arm were significantly associated with fewer microorganisms compared to neck or forearm
(odds ratio [OR] = 0.40, 95% confidence interval [CI] = 0.250.65, P < 0.05). CFU levels under transparent dressings were
not significantly different from outside (OR = 0.57, 95% CI = 0.221.45). Staphylococci were predominant at all sites. Other
significant (P < 0.05) predictors of higher CFU count included prolonged hospitalisation and medical/surgical patient status.
Discussion: Skin microorganism load was significantly lower at the upper arm or chest, compared to the mid- or base
neck. This may impact VAD site selection and subsequent infection risk.
Infection, vascular access device, central venous, intravenous catheter, skin microorganisms, colonisation, site selection, risk
Date received: 13 April 2018; accepted: 14 September 2018