AIMS:To evaluate use of an evidence-based discharge tool, the Post-Anaesthetic Care Tool and its impact on nursing assessment, communication, and management of patients in the postanaesthetic care unit. BACKGROUND:Postanaesthetic care unit nurses manage patients immediately after surgery and make clinical decisions on discharge readiness. There is a lack of evidence-based guidance on assessing, documenting, and communicating the patient's postoperative experience. The Post-Anaesthetic Care Tool, which includes instructions for assessing discharge readiness and incorporates the ISOBAR acronym, was developed following a comprehensive systematic review and expert consultation. DESIGN AND METHODS:This quasiexperimental, multicentre, nonrandomized study was conducted in three postanaesthetic care units in Australia. Participants were nurses providing care to adults postgeneral anaesthesia. Episodes of care were observed before (N = 723) and after (N = 694) introduction of the evidence-based tool. Statistical methods (Chi-Square and Mann-Whitney U-Tests) were undertaken to analyse nursing assessment, communication, and management outcomes before and after implementation of the Post-Anaesthetic Care Tool. RESULTS:The Post-Anaesthetic Care Tool was associated with statistically significant improvements in the frequency of nursing assessment and responsiveness to complications including pain, nausea/vomiting and hypothermia. After the tool's introduction, nurses requested more medical reviews. This was associated with increased recognition of clinical deterioration and significant improvements in clarity of handover from the postanaesthetic care unit to the ward. CONCLUSIONS:The structured discharge tool, Post-Anaesthetic Care Tool, was associated with improved nursing management of patients in the postanaesthetic care unit and enabled early identification and response to clinical concerns.