21st May 2025

Intraoperative care

During the operation, it is essential to ensure a patient’s blood glucose level is monitored. Capillary blood glucose monitoring is the preferred modality, as it is easily obtainable and accurately reflects the patient’s arterial blood glucose levels. This is unlike continuous glucose monitoring, which often lags. The target blood glucose range should be kept between 6 and 10 mmol/l.

Blood sugars should be monitored at these frequencies as a minimum: 

• VRIII – Hourly (especially if sedated/anaesthetised, on subcutaneous insulin and on the day of surgery).
• Subcutaneous insulin (not fasted) – Three to four times a day.
• Non-insulin diabetic medication – Twice a day.
• Diet controlled and CBG <10mmol/l – Once a day.

If a patient is on a VRIII, a solution containing glucose, sodium and potassium should be run alongside to meet the routine maintenance requirements. If there are significant delays and the CBG is >13mmol/l, ketones should be checked.