Impact of a theory-based intervention to prevent central line-associated bloodstream infections in a medical intensive care unit
: a before-and-after study

Student thesis: Doctoral ThesisDoctor of Philosophy


The incidence of Central Line-Associated Bloodstream Infections (CLABSIs) in Greek ICUs is higher than many other countries and occurs within the uncertain context of an eight-year financial crisis. Previous international research has extensively demonstrated that CLABSIs are largely preventable, but the complexity of the context in Greek ICUs means that it is not clear how this problem should be addressed. This study examined the effectiveness of a multifaceted, theory-based intervention on CLABSIs rates, adherence to CLABSI evidence-based preventive practices, behavioural determinants and contextual influences. An uncontrolled before-and-after study was conducted in one medical ICU in Athens, Greece. The study was informed by the Theory of Reasoned Action and self-efficacy and used survey questionnaires and non-participant observation (structured observation and field work). Specifically, the study examined at baseline CLABSIs and adherence rates, behavioural determinants (self-efficacy, behavioural intention, attitude, subjective norm and behavioural beliefs) of critical care physicians and nurses and contextual influences (culture, leadership and evaluation of practices). A multi-faceted theory-based intervention was implemented and evaluated for its impact on infection rates, behavioural determinants and contextual factors. The six-month intervention involved environmental changes to aid implementation of practices, education, improvement of skills, evaluation of CLABSI preventive practices, feedback, changes to policies to improve teamwork and leadership, persuasive communication and reminders. Findings indicated the intervention did not significantly reduce CLABSIs rates. However, adherence to central venous catheter handling will lead to mostly positive outcomes. Behavioural intention to adhere to CLABSI preventive practice Abstract 3 was strengthened after the intervention. The intervention also resulted in changes in the ICU’s culture, changes in policies to improve teamwork and communication, improvements in leadership for nurses with provision of positive feedback and rewarding by medical and nurse directors. A comprehensive education package, part of the intervention, was shown to be effective in increasing the knowledge of physicians and nurses. In the era of CLABSI prevention through quality improvement initiatives, this study contributes to implementation science field by clarifying which actions and activities have the greatest likelihood of consistent success, and provides evidence that CLABSI prevention, whilst not easy, is feasible within a resource-constrained context.
Date of Award1 Apr 2019
Original languageEnglish
Awarding Institution
  • King's College London
SupervisorJanet Anderson (Supervisor) & Tina Day (Supervisor)

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