Identification and confirmation of suspected unintended peripheral arterial cannulation during anaesthesia

Unintended arterial cannulation and injection of drugs may result in ischaemia and tissue necrosis. Various methods used to differentiate accidental arterial from intravenous cannulation have their own shortcomings. Here we present the case of a 13-year-old girl having an elective procedure under general anaesthesia and the challenges faced in distinguishing suspected intra-arterial cannulation from what was indeed an intravenous cannulation. We recommend the use of an open-ended saline-filled ‘T’ connector–syringe system and pressure transduction as the methods of choice to identify and confirm, respectively, a suspected arterial cannulation during anaesthesia