Continuous glucose monitoring and glycaemic variability in perioperative care: Implications for enhanced recovery after surgery

Perioperative glucose management has traditionally relied on intermittent capillary or laboratory values. These measurements remain essential, but they do not describe glycaemic variability, direction of change or time spent outside clinically relevant ranges. Continuous glucose monitoring can provide a detailed picture of perioperative glucose exposure and may reveal postoperative hyperglycaemia, hypoglycaemia and stress-related instability that intermittent testing can miss. This clinical feature focuses on patients for whom perioperative glucose surveillance is clinically indicated or clinically relevant, rather than proposing routine continuous glucose monitoring for all surgical patients. Current evidence supports its cautious use as an adjunct to point-of-care or laboratory testing, particularly for postoperative surveillance and service evaluation. Sensor readings should not be used as the sole basis for insulin or dextrose treatment during surgery or physiological instability. Within enhanced recovery pathways, the most defensible role is structured monitoring that supports risk stratification, clinical governance and future trials of glucose-stabilising interventions.