Anaesthesia

1. Perioperative Glycemic Control in
DM patients
Dr Kassim Bello Gogori
Department of Anaesthesiology and
Intensive Care
02-05-2023

2. OUTLINE
• INTRODUCTION
• PREOPERATIVE EVALUATION
• PERIOPERATIVE MANAGEMENT
• POSTOPERATIVE PERIOD
• EMERGENCY SURGERY AND DM
• CONCLUSION
• REFERENCES

3. INTRODUCTION
• Diabetes mellitus is a metabolic disorder with an increasing global
incidence and prevalence
• With an increasing incidence worldwide, DM will be likely a leading cause
of morbidity and mortality in the future.
• A survey carried out recently by WHO African region indicated up to 15%
of Adults aged 25-64 have diabetes.
• Prevalence in Nigeria at 2018 was 5.77%.
• Poor peri-operative glycaemic control increases the risk of adverse
outcomes.

4. • The effects of surgical stress and anaesthesia have unique
effects on blood glucose levels, which should be taken into
consideration to maintain optimum glycaemic control
• Hyperglycemia predisposes patients to post-operative sepsis,
impaired wound healing, endothelial dysfunction.
• Through careful glycaemic management in perioperative
period, we may reduce morbidity and mortality and improve
surgical outcomes

5. DEFINITION (WHO)
• “ A metabolic disorder of multiple etiology
characterised by chronic hyperglycaemia with
disturbances of carbohydrate, fat and protein
metabolism resulting from defect in insulin
secretion, insulin action or both.

6. WHO 2019 Classification
• Type 1
• Type 2
• Hybrid
• Other specific types
• Unclassified
• Hyperglycemia first detected in Pregnancy

7. PRE-OPERATIVE EVALUATION

8. GENERAL PRINCIPLES
• Diabetes should be well controlled prior to elective surgery.
• Avoid insulin deficiency and anticipate increased insulin
requirements.
• The patient’s diabetes care provider should be involved in the
management of their patient’s diabetes peri-operatively.

9. • Patients with diabetes should be on the morning list,
preferably first on the list.
• Patients should be well hydrated before the procedure.
• High Carbohydrate drinks recommended especially for
patients with type 2 DM
• Target glucose for the preoperative period is between 6-
10mmol/L.

10. GOALS
• Establishment of certain glycemic target levels,
<10mmol/L in critical patients and <7.6mmol/L in stable
patients.
• Avoidance of severe hyperglycemia or hypoglycemia.
• Prevention of ketoacidosis.
• Maintenance of physiological electrolyte and fluid
balance.
• Reduction of overall patient morbidity and mortality.

11. To asses History/Examination Investigations
1-Blood sugar control Hypo/ Hyperglycemic
episodes, Hospitalization
FBS RBS HbA1C
2- Anemia, Leukocytosis Basic invx, H/O frequent
infection
FBC
3- Neprhopathy H/O HTN, swelling over
body, recurrent UTI
Urinalysis urine mcs and
RFT
4- Cardiac status H/O angina, MI , Exercise
intolerance
ECG, CXR, ECHO

12. 5- ANS Early satiety, abdominal
distention, orthostatic
syncope
Postural change in BP, HR
Tachycardia response to
atropine
6- Retinopathy Visual disturbances Fundus examination
7- PVD H/O intermittent
claudication, Non healing
ulcer, blanching of feet
USG doppler
8- Airway Stiff joint syndrome(prayer
sign, palm print test)
obesity
X-ray of the cervical spine
AP and lateral
9-Metabolic & Electrolyte H/O- Starvation, Infection
Sign of DKA
ABG, Urinary stones
Sr electrolyte

13. PRAYER SIGN
A positive "prayer sign" can be
elicited on examination with the
patient unable to approximate
the palmar surfaces of the
phalangeal joints while pressing
their hands together; this
represents
cervical spine immobility and the
potential for a difficult
endotracheal intubation.

14. • PLAN AND ORDERS
• Consent
• NPO orders
• Anxiolytics
• Stop long acting insulin, biguanides, sulfonylureas,
thiazolidinediones, GLP-1 agonists, alpha glucosidase
inhibitors night before surgery.
• Stop OHA 24 to 48 hours before surgery

15. • Morning blood sugar and s. electrolytes to be done
• Morning IV fluid according to regimen
• Arrange Glucometer, dextro-strips, insulin etc
• Careful transport of the patient
• To be taken as the first case

16. PRE-OP NPO
• Atleast 6 hours for solid foods.
• Patients with gastroparesis, 12 hours may be needed. Such
patients are given H2 receptor blocker (Ranitidine) and
prokinetics (metoclopramide).
• When fasting exceeds 8-10 hours then insulin- glucose
infusion has to be started to prevent catabolism.

17. ANAESTHETIC CONCERNS
• DM affects oxygen transport by causing glucose binding to
Hemoglobin
• DM is considered CAD equivalent.
• Chronic kidney disease is asymptomatic in diabetic and
usually advanced.
• Autonomic dysfunction;
Exagerated Hypotension
– Risk of hypothermia
– Sympathetic response are blunted
– Silent MI

18. • Inhibits intestinal motility, delayed gastric emtying.
• Difficult Airway-
 Restricted joint movement
 Obesity
• Therapy related-
 Sulphonylureas – hypoglycemia
 Metformin - lactic acidosis
 Incretins & amylin - delays gastric emptyig , nausea

19. PERIOPERATIVE MANAGEMENT
• Monitor Blood glucose on admission, and hourly during the
day of surgery
• Aim for blood glucose level of 6-10mmol/l
• Postpone elective surgery if possible if glycaemic control is
poor (HbA1c ≥ 9%)
• An Endocrinologist should be consulted in the periop period
to jointly manage patients scheduled for major surgery.
• Choice of Anaesthetic technique…..
Regional vs General anesthesia

20. • The nature and extent of therapy depends on
 The type of the surgery
 Magnitude of the surgery
 Insulin regime
 Pre-op glycaemic control
 Resumption of patient usual diet

21. Minor Surgery
• Type 1 DM
 Omit morning dose of insulin if Blood glucose < 7mmol/L
Give half the normal dose if > 7mmol/l
 Measure the blood glucose conc 1hour before surgery,
once during the surgery and 2hourly postop until oral
intake
 Recommence insulin when the pt start oral intake

22. • Type 2 DM
 On Diet control
 On OHA

23. PATIENTS ON DIET ALONE
• No specific therapy is required, But more frequent RBS monitoring during
the peri-operative period is recommended.
• If RBS remains above 10 mmol/L in the pre- or peri-operative period, an I-
G infusion should be commenced and continued until they resume eating.
• RBS should be monitored every 4 – 6 hours until they resume their usual
meals.
• Patients who are hyperglycemic peri- or post-operatively may require
supplemental insulin and/or the initiation of specific OHA

24. PATIENTS ON OHA (WITHOUT INSULIN)
• Omit OHA 24-48 hours before surgery.
• Restart it when patients are able to resume normal meals.
• Measure Blood glucose conc 1hr before surgery, once during surgery and
2hly until return of oral intake.
• Commence an I-G infusion if the RBS>10mmol/l, if surgery is prolonged
and or if the patient is usually treated with more than one oral AHG agent.
• Subcutaneous insulin may be required post-operatively
• Recommence OHA when the patient starts oral intake.

25. MAJOR SURGERY
• This group includes patients with type 1 diabetes or patients
with type 2 diabetes who require day time insulin injections.
• Check blood glucose and potassium conc. Preoperatively.
• Maintain the usual insulin doses and diet the day before, and
fast from midnight.
• For all pts, discontinue all short acting insulin and OHA on the
day of surgery.

26. • Patients with T2DM should take none , or up to 1⁄2 of their dose of
long-acting or combination insulin, on the day of surgery
• Patients with T1DM should take a small amount usually 1/3 of their
usual morning long-acting insulin dose on the day of surgery
• Start variable-rate infusion according to sliding scale insulin regime.
• Measure Blood glucose conc. 2hly from start of infusion, hourly
during surgery and 2hourly until start of oral intake

27. INSULIN INFUSION REGIMES
• Various type of infusion regimes have been recommended.
• Most common ones being......
 VRIII(Variable-Rate IV Insulin Infusion) according to sliding
scale
 GKI Regime(Alberti Regime)

28. VRIII
• Make up a 50 ml syringe with 50 units of soluble human insulin in
49.5mls of 0.9% sodium chloride solution. This makes the
concentration of insulin 1 unit per ml.
• The substrate solution to be used alongside the VRIII should be
selected from:
 0.45% saline with 5% glucose and 0.15% KCl
 0.45% saline with 5% glucose and 0.3% KCl
• The rate of fluid replacement must be set to deliver the hourly fluid
requirements of the Individual.( volumetric infusion pump).
• Delivery of the substrate solution and the VRIII must be via a
single cannula with appropriate one-way and anti-siphon
valves

29. • Glucose 4% and 0.18% Nacl; 10% or 5% glucose may be
acceptable
• If serum K <4.5mmol/l, add 10mmol/l of KCL to each 500ml
bag of glucose.

31. VRIII INFUSION
Blood glucose(mmol/l) Initial rate of insulin
Infusion(units/h)
<4.0 0.5
If long acting insulin has
been cont. tx as for
hypoglycemia
4.1-7 1.0
7.1-9 2.0
9.1-11 3.0
11.1-14 4.0
14.1-17 5.0
17.1-20
>20
6.0
Check infusion running,
and seek diabetes team or
medical advice)

32. ALBERTI REGIMEN(GKI)
• The Alberti Regimen (1979) combines regular insulin,
dextrose, and potassium in a single infusion.
• This helps to prevent inadvertent insulin infusion without
dextrose, thus reducing the risk of hypoglycemia.
• The amount of insulin added to a bag is dependent on the
patient’s capillary glucose.

33. • ADVANTAGE
• Simple
• Safe
• Reproducible
• Remove the risk of accidental insulin infusion without
dextrose.
• DISADVANTAGE
• × Need to change the bag if dose of insulin needs to be
changed.
• × This regimen is intensive and wasteful, and has the
potential for error.

34. • Alberti regimen consists of
 500mls of 10% Glucose
 Add 10-15IU of soluble insulin
 10mmol of KCL per 500ml bag
• Infuse at 100mls/hr
• Provide insulin 2-3u/hr, K 2mmol/hr and glucose 10g/hr
• If 10% dextrose not available, 5% dextrose can be use.

35. GKI Infusions
Blood
glucose(mmol/L)
S. Insulin(U) to be
added to each
500ml of bag of de
Blood K(mmol) KCL(mmol/l) to be
added to each
500ml of bag
<4 5 <3 20
4-6 10 3-5 10
6.1-10 15 >5 None
10.1-20 20
>20 review If K level not
available add
10mmol of KCL to
each bag

36. TIGHT CONTROL REGIMEN
Target Blood Sugar is 4.5-6mmol/l.
Indications:
Pregnancy, CPB, Neurosurgery.
Advantages:
Improve wound Healing,
Prevent wound infection,
Improve neurological outcome

37. THE POST-OPERATIVE PERIOD
• Insulin-glucose infusions should be continued until the
patients can resume an adequate diet (or atleast 24 hrs).
• I-G infusions should ideally be stopped after breakfast,
and a dose of subcutaneous insulin (or oral AHG) is given
before breakfast.
• Hyperglycemia detected post-operatively in patients but
not previously known to have diabetes, should be
managed as if diabetes was present, and the diagnosis of
diabetes reconsidered once the patient has recovered
from their surgery.

38. • Diabetes medication requirements may be increased (or
occasionally decreased) in the post-operative period, and
frequent BGL monitoring is therefore essential.
• Endocrinologist must be available for the post- operative
management of glycaemic instability.

39. EMERGENCY SURGERY
• This often poses a management dilemma if the surgical
procedure is urgent despite poor glycaemic control
• Such patients should be reviewed and managed by the
endocrinologist
• Blood glucose concentration up to 15mmol/l may be
accepted for surgery

40. Usually Infected
Usually Uncontrolled
Dehydrated
Metabolic decompensated
Increased resistance to insulin
More chances of acute Hyperglycemic
complication

41.  Little time for stabilisation of patients ,but if 2-3 hr available
• correction of fluid and electrolyte imbalance .
• Correct hyperglycemia.(start I-G infusion if sugar > 10mmol/l)
• Treat acidosis.
• Avoid hypoglycemia.
 However, surgery should not be delayed in an attempt to treat
ketoacidosis completely, if the underlying condition has the
possibility of leading to further metabolic deterioration.

42. • Likelyhood of intra-op hypotension and arrhythmia is more
particularly if patient has pre-op acidosis or hypokalemia.
• Intra-op sugar to be monitored more frequently.

43. CONCLUSION
• Careful perioperative glucose management can reduce
surgical complications as well as hyper- or hypoglycaemic
sequelae which ultimately improves morbidity and mortality.
• Remember: Hypoglycemia is more dangerous
than hyperglycemia.

44. • https://www.afro.who.int/health-topics/diabetes
• C.Y Lee, Manual of Anesthesia.
• Ketan D., Nicholas L., Daniel F., et al.
Management of Adults with diabetes undergoing
surgery and elective procedures: Improving
Standards. Joint British Diabetes Societies for
Inpatient Care.
• Keith G.A., Ian D. Oxford Handbook of
Anaesthesia. Fourth edition, 2016.

45. THANK YOU FOR LISTENING