Hyperglycaemia

Three kinds of patient

1. Hyperglycaemia despite no diabetes

2. Hyperglycaemia with undiagnosed diabetes – hidden risk of HONK or DKA.

3. Hyperglycaemia with diagnosed diabetes

Cause	· ↑Hepatic glucose production (mainly this) · ↑Insulin resistance
Bad effects	· ↑Mortality · ↑Morbidity of various sorts · ↑↑Infection risk (even if >6) Lower risk (paradoxical) in diabetics because their cells are used to it
Good effects	· Whatever reason the stress response evolved for · Makes cardiac myocytes resistant to ischaemia
Unknowns	· Which is more important – the good of the bad? · Which is more important for the bad – the high sugar or its cause?

Background	· In sick diabetics, high sugar is associated with bad outcome
Groups	· Aggressive vs lax control
Outcome	· Aggressive group had higher mortality
Explanation	· Cells of diabetic patient become accustomed to hyperglycaemia

Target BSL

· Rule of thumb 6-10

o Lower end if non-diabetic

o Higher end if diabetic

· Need HbA1c to know which of the three groups a patient belongs to

· Should we be checking this in all patients having major surgery?

Elective cancellation

· HbA1c >9%: cancel

· BSL ↑↑↑: cancel (but safe threshold is unknown)