Complications related to arterial line catheters and monitoring reported to webAIRS, 2009–2023

Arterial catheters are commonly inserted for intraoperative monitoring but are known to cause complications. We analysed all cases of arterial catheter complications and incidents related to arterial line monitoring reported to webAIRS. Anaesthetists voluntarily reported cases between 2009 and 2023. Included incidents met keyword search criteria and involved the insertion and presence of an arterial catheter, covering complications relating to the accuracy of arterial blood pressure readings, equipment or monitoring malfunction or human error related to equipment usage. Our aim was to promote awareness of both common and rare complications of arterial lines. Of the 10,518 incidents, 53 incidents met criteria, with 54 events described. Twenty-seven (50%) incidents were related to equipment failure, 17 (31%) compromised flow, five (9%) nerve injury, two (4%) medication error, one (2%) injury to skin, one (2%) infection and one (2%) inability to place an arterial catheter. The most common equipment problem was related to inappropriate transducer height causing inaccurate readings. No harm occurred in 16 (29.5%) of the patients, mild harm in 25 (46%), moderate harm in 10 (18.5%), severe harm in two (4%) and death in one (2%). Clinician vigilance is critical in the preparation, insertion and monitoring of arterial catheters, to allow the detection of problems and prevention of patient harm.