An unplanned intensive care unit admission within 24 hours of a procedure with an anaesthetist in attendance (UIA) is a recommended clinical indicator It is designed to identify preventable iatrogenic complications. Often understood as a specific anaesthetic outcome, its value has been repeatedly questioned. Iatrogenic complications however often result from successive mishaps. In the specific context of an UIA these complications can be related both to anaesthesia and surgery. UIA is therefore probably more a global indicator of the safety of surgical care (anaesthetic and surgical) rather than a specific anaesthetic outcome. Its utility as such is however unknown. The purpose of this study was to assess the value of UIA as a global measure of avoidable iatrogenic complications in surgical patients. Using computerised patient records and medical charts, all patients with an UIA over a study period of five years were identified. The proportion, cause and preventability of iatrogenic complications amongst these patients were assessed. A total of 188 UIA patients were identified by peer reviewers. Of these, 87% to 92% had a complication caused by anaesthesia and/or surgery. Anaesthesia was found to be responsible for 24% to 31% of iatrogenic complications. All other cases related to the combination of anaesthesia and surgery or surgery alone. Of these, 74% to 92% of complications were found to be preventable. Despite intrinsic limitations of the retrospective chart review method, UIA can be considered as a valuable tool to detect avoidable iatrogenic complications related to both surgical and anaesthetic care.