Rare occurrence of upper-limb ischaemia necessitating transhumeral amputation following axillary arterial line placement.

Arterial cannulation, commonly performed in the radial artery, is a widely used method for continuous blood pressure monitoring. Occasionally, the axillary artery is used as an alternate site of cannulation. However, complications like occlusion can lead to adverse events and severe outcomes. We present a case of axillary arterial line placement resulting in ischaemic limb injury and amputation, highlighting the need to recognise risk factors.A woman in her mid-60s underwent a lobectomy for adenocarcinoma of the lung and suffered postoperative complications resulting from arterial line placement. Despite interventions, she developed progressive ischaemia of her left upper limb, necessitating amputation. This case highlights the risks associated with arterial catheterisation and potential adverse outcomes, offering recommendations for arterial line placement in high-risk patients.