Diabetes

1. Surgery in patients with
diabetes
Dr M A C K A Naser
Registrar/Medicine

2. Problems of diabetes during
surgery
 Fasting causes several problems in
type I DM
 They need basal insulin to prevent
ketosis
 Develop hypoglycemia
 Fating has little impact in type II,
unless hypoglycemic agents are taken

3. Metabolic changes
 Surgery & the severity of surgery increases
the anti insulin hormones
 Increased adrenaline, ACTH, cortisol & GH
aggravate insulin def & resistance
 This increases catabolism with increased
glycogenolysis, proteolysis & lipolysis
 Gluconeogenesis is increased due to stress
 From lactate, pyruvate, alanine & glutamate
from liver & kidney
 Resultant hyperglycaemia is more pronounced in
diabetics than non diabetics

4. Metabolic changes
 Ketoacidosis
 In the absence of insulin lipolysis is increased,
leading to ketoacidosis
 Plasma levels of FFA, glycerol & KB increase
 Metabolic acidosis can occur even in the presence of
near normal glucose levels
 All these metabolic changes are aggravated by some
types of anaesthesia
 High dose opiates
 Regional block
 These changes cause increased insulin requirement in
type I & possible requirement of insulin in type II

5. Principles of management
 Fundamental principle is monitor & record
capillary blood glucose regularly & act
accordingly
 Most problems occur due to
 Forgotten to measure glucose
 Very low values ingnored
 Target glucose
 During surgery 7-11 mmol/l
 At normal levels – hypoglycaemia
 Above 11 mmol/l – increased UOP & dehydration

6. Principles of management
 Any other fluid (except the direct
dextrose) during surgical period
should not contain glucose
 Hartman’s solution is contraversial
 Lactate increases gluconeogenesis
 Blood glucose rise in type II
 If fluid restriction is needed give
glucose as 25% or 50% dextrose, via
CVP line

7. Principles of management
 Electrolytes:
 K levels should be monitored peri operatively
 K level varies due to
 Insulin promotes K uptake by muscle, liver &
adipose tissue
 Dehydration causing K shift from IC to EC fluid
 Acidosis: exchange of H/K; conserving K by
kidney
 Most pts with normal renal function require
20mmol of K per litre of fluid

8. Emergency surgery
 Upto 5% of pts require urgent surgery at some time
 Danger:
 Aggravation of DM
 Ketoacidosis (some times DKA may mimic acute abdomen)
 Glycaemic control & acid base balance should be evaluated
by
 Blood glucose
 Electrolytes
 Blood gas
 Urinary ketones
 IV fluids should be given with pottasium & insulin as
indicated
 In ~60% of pts the acute abdomen resolves without
laparotomy after correction of metabolic abnormalities
 But autonomic neuropathy may mask symtpoms of real
acute abdomen

9. Management strategies
 Ommision of antidiabetics and careful
monitoring
 Separate glucose-insulin infusions
 GKI (glucose/K/insulin) infusion

10. Ommision of antidiabetics and
careful monitoring
 Suitable for:
 Short procedures (gastroscopy, dental extraction) –
all patients
 Minor procedures: arthroscopy, D&C – all patients
 Moderate procedures: hernia repair, hysterectomy –
in patients not prone to ketosis eg: type II pts
 Pt is placed early on the list
 Usual drugs omitted and blood glucose monitored
carefully with glucometer
 Single dose of soluble insulin given if RBG>17mmol/l
 If blood glucose continues to rise for 2hrs – IV insulin
regime should be considered
 Pts revert to normal regime when they can eat &
drink

11. Separate glucose-insulin infusions
 Suitable for
 All major surgeries
 Moderate or major surgery in type I DM
 Major surgery in type II DM
 Pts should not be first on the list. Should be placed towards
the end or afternoon
 Blood glucose should be in the desirable range – 7-
11mmol/l
 Infusion: 10% dextrose 500ml + KCl 10mmol – 100ml/hr
 Insulin infusion: 50u of S.Insulin in 50ml of 0.9% N.Saline
by a syringe driver and adjusted according to blood glucose
 Drop rates adjusted by syringe pump, not by naked eye
 Blood glucose monitored hourly

12. GKI (glucose/K/insulin) infusion
 Suitable for
 Moderate or major surgery in type I DM
 All major surgery in type II
 Infusion: 500ml of 10% dextrose + KCl
10mmol + 10 u of S.insulin given at rate of
100ml/min
 Blood glucose every hour
 If successive 2 measures are 4-7mmol/l –
reduce insulin to 5u/500ml
 If 2 measures are 17mmol/l or more
increase insulin to 20u/500ml

13. Regimes for surgery in DM
Type of
diabetes
Minor
surgery
Moderat
surgery
Major
surgery
Emerge
ncy
Type I
Always treated
with insulin &
ketosis prone
Fast &
check
Glucose
insulin
or GKI
Glucose
insulin
or GKI
Glucose
insulin
Type II
Diet/tablets/ins
ulin
Not prone to
ketsosis
Fast &
check
Fast &
check
Glucose
insulin
or GKI
Glucose
insulin

14. Post operative management
 Once the patient is eating and
drinking can return to usual regime
 Type I pts must take the first dose of
s/c insulin 60 minutes before
terminating IV insulin