Introduction: Millions of acute care hospital patients need a peripheral intravenous catheter (PIVC) each year. However, up to half of PIVCs remain in situ when not being used, and 30%–50% of intravenous (IV) catheters develop complications or stop working before treatment is finished, requiring the insertion of a new device. Improved assessment could prompt timely removal of redundant catheters and prevent IV complications. This study aims to validate an evidence-based PIVC assessment and decision-making tool called I-DECIDED and evaluate the effect of implementing this tool into acute hospital clinical practice.

Methods and analysis: The protocol outlines a prospective, multicentre, mixed-methods study using an interrupted time-series (multiple measures preintervention and postintervention) implementation at three Australian hospitals between August 2017 and July 2018. The study will examine the effectiveness of the I-DECIDED assessment and decision-making tool in clinical practice on prompting timely PIVC removal and early detection of complications. Primary outcomes are prevalence of redundant PIVCs (defined as device in situ without a clear purpose), IV complications (occlusion, dislodgement, infiltration, extravasation and phlebitis) and substandard dressings (loose, lifting, moist or soiled); device utilisation ratios; and primary bloodstream infection rates. Secondary outcomes including staff barriers and enablers to PIVC assessment and removal, patient participation, documentation of PIVC assessment and decisions taken to continue or remove the PIVC will be recorded. Using the Promoting Action on Research Implementation in Health Services framework, we will undertake staff focus groups, bedside patient interviews and PIVC assessments and chart audits. Patients aged 18 years or more with a PIVC will be eligible for inclusion.

Ethics and dissemination: Ethical approval from Queensland Health (HREC/17/QPCH/47), Griffith University (Ref No. 2017/152) and St Vincent’s Health and Aged Care Human Research and Ethics Committee (Ref No. 17/28). Results will be published.

Trial registration number: ANZCTR: 12617000067370; Pre-results.