Delayed recovery following general anaesthesia: A comprehensive review of causes, assessment, and treatment

Background: Delayed awakening after general anaesthesia is a significant clinical event, defined as the failure to regain consciousness within the expected postoperative period. While most cases result from residual anaesthetic effects, delayed emergence may also suggest underlying metabolic abnormalities or neurological injuries, which necessitate urgent evaluation.Methods: A literature review was conducted for studies published between 2010 and 2025. Searches were performed across PubMed/MEDLINE, Embase, the Cochrane Library, and Google Scholar using predefined keywords and relevant MeSH terms related to delayed emergence, anaesthetic drug clearance, metabolic disturbances, and neurological causes. Relevant peer-reviewed articles, clinical guidelines, and review papers in English were included in the review.Discussion: Key causes of delayed recovery include prolonged anaesthetic action, hypothermia, electrolyte disturbances, hypoglycemia, and central nervous system pathology. The development of Bi-spectral index (BIS) monitoring and the availability of newer neuromuscular blockade reversal agents have improved predictability and management of delayed emergence. A structured approach to diagnosis, beginning with assessing airway patency, ventilation, hemodynamic status, and neurological assessment, is essential for identifying reversible causes rapidly.Conclusion: Delayed emergence from general anaesthesia requires a stepwise evaluation and timely intervention. Traditional diagnostic approaches, integrated with modern monitoring technologies, enhance early recognition and allow for targeted management. This review provides an updated and practical framework for clinicians managing delayed postoperative recovery.