Idle peripheral intravenous cannulation: an observational cohort study of pre-hospital and emergency department practices

Background: Unused ('idle') peripheral intravenous catheters (PIVC) are those not used within 24 hours of insertion. There is little data on cannulation practices and idle PIVC rates in emergency settings, especially the pre-hospital environment.

Methods: This was an observational cohort study set in south-east Queensland, Australia using data from a large tertiary level emergency department (ED) and the local statutory ambulance service. Demographic, clinical and PIVC data were collected over two periods; 9 February–18 March 2017 and 5 January–4 February 2018. Adult patients were included if they were allocated an Australasian triage scale (ATS) category between 2 and 5, and had a PIVC inserted in the pre-hospital setting or ED. PIVC use was defined as idle if no fluids, medications or contrast were administered intravenously within 24 hours of insertion. Comparisons between pre-hospital and ED practice and idle PIVC status were undertaken using descriptive statistics and logistic regression. 

Results: A total of 1249 patients with a PIVC (372 pre-hospital; 877 ED) were included. Overall, 366 PIVCs (29.3%; 95% CI 26.9%–31.9%) remained idle at 24 hours. In the pre-hospital group, 147 (39.5%) PIVCs inserted were not used pre-hospital, and 74 (19.9%) remained idle. In comparison, 292 (33.3%) PIVCs placed in the ED remained idle. ED staff more frequently inserted PIVCs in the antecubital fossa than paramedics (65.5% vs. 49.7%), where forearm PIVC insertion was more common pre-hospital than in ED (13.7% vs. 7.4%). Nursing staff inserted idle PIVCs at a rate of (35.1%) compared to doctors (29.6%) and paramedics (19.9%). Having a PIVC inserted in the ED was the only factor significantly (p ≤.001) predicting an idle outcome (Odds Ratio: 2.4; 95% CI 1.7–3.3). 

Conclusion: One-third of PIVCs inserted within the emergency setting remained idle, suggesting unnecessary risk and costs. Pre-hospital and ED PIVC insertion practices differed, with idle PIVCs 2.4 times more prevalent if inserted in the ED than pre-hospital and with greater use of antecubital insertion. Reasons for these differences are not well understood and requires more targeted research.