High blood sugar slows down wound healing and increases the risk of infection. Recovery from surgery and hospitalization is often prolonged. There is also an increased risk of complications related to the surgery and cardiovascular events.
Before a planned surgery, it would be ideal to have a glycated haemoglobin HbA1c level below 53–64 mmol/mol (7–8%). With higher values, postponing the surgery should be considered. The blood sugar in the morning and before meals should be ideally on the level of 5–8 mmol/l before the planned surgery, and post-meal levels should be below 10–12 mmol/l.
Emergency surgeries have to be performed regardless of the blood sugar level. In such cases, blood sugar is managed and monitored effectively during and after the surgery.
The body's stress response to surgery and immobility can raise blood sugar levels during and after the procedure. Blood sugar is usually monitored every 1–2 hours during and after the surgery or procedure. The aim is to maintain blood sugar levels at 6–10 mmol/l. Depending on the duration of the surgery, insulin is administered either through injections or directly into the vein along with a glucose drip.