Peri operative management of diabetes patients

1. By
MAHMOUD IBRAHIM
ANESTHESIA S REGISTRAR

2.  Diabetes mellitus is defined as a syndrome
characterized by sustained hyperglycemia
due to insulin deficiency, impaired insulin
action or a combination of both.

4. Classification of Diabetes
• Type 1 diabetes
– β-cell destruction
• Type 2 diabetes
– Progressive insulin secretory defect
• Other specific types of diabetes
– Genetic defects in β-cell function, insulin action
– Diseases of the exocrine pancreas
– Drug- or chemical-induced
• Gestational diabetes mellitus (GDM)
ADA. 2. Classification and Diagnosis. Diabetes Care 2015;38(suppl 1):S8

5. Diabetes affects 10–15% of the surgical population
patients with diabetes undergoing surgery have greater
complication rates, mortality rates and length of hospital stay.
Anaesthetists and other peri-operative care providers should
be knowledgeable and skilled in the care of patients with
diabetes.

6. high pre-operative and perioperative glucose and
glycated haemoglobin (HbA1c) levels are
associated with poor surgical outcomes.
 increase in mortality
 increase in the incidence of postoperative respiratory infections
 a doubling of surgical site infections
 increase in postoperative urinary tract infections
 a doubling in the incidence of myocardial infarction
 increase in acute kidney injury
Frisch et al., 2010

8. AIMS:
 Glycaemic control:
 Co morbidities:
 High risk patients:
 Management plan:

10.  Mortality rate from heart disease is 24
times greater
 A comprehensive cardiac assessment :in all
patients undergoing intermediate or major
non- cardiac surgery.
 Major surgery: noninvasive myocardial function
studies (dobutamine stress echo) or coronary
angiography.

11. Orthostatic hypotension - sign of autonomic
neuropathy.

12.  Early stage: abnormality of HR response during deep
breathing
 Intermediate stage: abnormality of Valsalva response
 Late stage: presence of postural hypotension
 The test are valid marker of DAN if following factors ruled
out.
1. End organ failure
2. Concomitant illness
3. Drungs: antidepressents, antihistamines, diuretics,
vasodilators, sympathatic blockers, vagolytics.

13.  Delay in gastric emptying – no gastric outlet
obstruction.
 increased amount of gastric contents - the risk
of acid aspiration during the induction
 fasting guidelines - preoperative prokinetic
drugs- H2 blockers.

14.  Significant risk during airway management.
 Affects temporomandibular, atlantooccipital, and
other cervical spine joints.
 Short stature and waxy skin.
Related to chronic hyperglycemia and
nonenzymatic glycosylation of collagen and its
deposition in joints.

15.  patient unable to approximate
the palmar surfaces of the
phalangeal joints while pressing
their hands together;
 Represents cervical spine
immobility and the potential for
a difficult endotracheal
intubation .

16.  Fasting serum glucose concentration
 HbA1c
 Serum electrolytes
 Blood urea nitrogen
 Creatinine.
 Urinalysis - assess for proteinuria and microalbuminuria.

17.  Surgical stress response
 NBM
 Altered consciousness - masks the symptoms of
hypoglycaemia
 Circulatory disturbances - which may alter the
absorption of s/c insulin.

19.  IV induction agents
 Etomidate
 Midazolam
 Opioids
 Inhalational ( in vitro)
 Epidural anesthesia

24.  In patients likely to miss one meal only- by
manipulating the patient’s normal medication.
 Some agents (e.g. sulphonylureas and insulin)
act by lowering glucose concentrations: stop
or modify.
 Others work by preventing glucose levels
from rising (e.g. metformin): continue.

27. VRIIIs are preferred in:
 patients who will miss more than one meal
 type-1 diabetes who have not received background
insulin
 poorly controlled diabetes (HbA1c > 69 mol.mol1)
 Most emergency surgeries.
Variable-rate intravenous insulin infusions should be
administered and monitored by appropriately
experienced and qualified staff.

28.  Hazards: hypoglycaemia- hyperglycaemia -ketosis on cessation-
hyponatraemia.
 written guidelines: safe use of VRIII - conversion from VRIII to
the usual diabetes treatment.
 steady supply of substrate : glucose 5% in saline 0.45% with
KCL 0.15% or 0.3% as a maintenance fluid.
 Delivery of the substrate solution and the VRIII must be via a single
cannula with appropriate one-way and anti-siphon valves .
 hourly monitoring of the CBG (to keep the CBG at 6–10
mmol/L)
 VRIII Shouldn’t be discontinued until alternative
subcutaneous insulin has been administered.

31. GOALS:
 maintain glycaemic control (An intra-operative CBG range of 6–10
mmol/l).
 prevent further deterioration of pre-existing end organ damage and
minimise the metabolic consequence of starvation and surgical stress.
 Early return to normal diet and usual preoperative diabetic regimen.
 prevent complication.
 Greater concern for aseptic precaution.

32.  Timing: 1st on morning list.
 Positioning: pr. Areas
 Anesthetic technique: acc. To type of surgery , co-morbidities
and presence of contraindications
 Induction of GA:
 Careful titration
 RSI
 Difficult intubation
 Multimodal analgesia : care with NSAIDs
 Temp control : hypothermia leads to insulin R, hyperglycemia,
decreased wound healing and infection.

33. ADVANTAGES
 Blunts the stress response
 An awake patient –
hypoglycaemia readily
detectable.
 Decreased chance of Aspiration,
PONV and Thromboembolism.
 Rapid return to diet and Sc
insulin/OHA
DISADVANTAGES
 If autonomic neuropathy is
present, profound hypotension
may occur.
 Infections and vascular
complications may be
increased (epidural abscesses)
 Medicolegal concern of risk of
nerve injuries and higher risk
of ischaemic injury due to use
of adrenaline with LA

34.  If CBG exceeds 12 mmol/L, capillary blood ketone levels should be
measured (point-of-care devices are available).
 If the capillary blood ketones are > 3 mmol/L or there is significant
ketonuria (> 2+ on urine sticks) the patient should be treated as
having DKA ( medical emergency).
 If DKA is not present, the high blood glucose should be corrected
using SC insulin or by altering the rate of the VRIII (if in use). If two
SC insulin doses do not work, a VRIII should be started.
 SC rapid-acting insulin 0.1 IU/kg (up to a maximum of 6 IU), using a
specific insulin syringe. CBG checked hourly and a second dose
considered only after 2 h. A VRIII should be considered if the patient
remains hyperglycaemic.

35. For a CBG 4.0–6.0 mmol/L :
50 ml glucose 20% (10 g) should be given
intravenously.
For hypoglycaemia < 4.0 mmol/L:
100 ml (20 g) should be given intravenously.

36.  There is a limited evidence base for the
recommendation of optimal fluid management
of the adult diabetic patient undergoing
surgery.
 It is now recognised that Hartmann’s solution
is safe to administer to patients with diabetes
and does not contribute to clinically significant
hyperglycaemia

37.  AIM: to provide glucose as a substrate to
1. prevent proteolysis, lipolysis and ketogenesis,
2. optimise intravascular volume status
3. maintain plasma electrolytes within normal .
 Avoid iatrogenic hyponatraemia from the administration of hypotonic
solutions. Glucose 5% solution should be avoided.
 half strength ‘normal’ saline combined with glucose is, theoretically, a
reasonable compromise to achieve these aims.
 glucose 5% in saline 0.45% pre-mixed with either KCL 0.15% (20
mmol/L) or KCL 0.3% (40 mmol/L), depending on the presence of
hypokalaemia (< 3.5 mmol/L).
 Additional Hartmann’s solution or another balanced isotonic crystalloid
solution should be used to optimise intravascular volume status.

38.  The postoperative blood glucose management
plan, and any alterations to existing
medications, should be clearly communicated
to ward staff.
 Patients with diabetes should be involved in
planning their postoperative care.
 If SC insulin is required in insulin-naive
patients, or the type of insulin or the time it is
to be given is to change, the specialist diabetes
team should be contacted for advice.

39.  Choices:
1. Modification of normal medication:well pt- minor surgery
2. Use of a VRIII: default technique
3. Use of a fixed-rate IV insulin infusion :in DKA
 In case of emergency surgery in patient with
DKA:
 Senior multidisciplinary management
 High mortality
 Discussion : requirement for surgery ( -ve laparotomies??,
preoperative resuscitation ( ICU admission??)

40. Restarting oral
hypoglycaemic
medication
Restarting
subcutaneous insulin
for patients already
established on insulin
or the patient on basal
and bolus insulin
For the patient on a
twice-daily, fixed-mix
regimen
For the patient on a
continuous SC insulin
infusion

41.  Metformin :key drug in the treatment of type 2 DM.
 Mechanism: insulin sensitizer, inhibits gluconeogenesis
 If sole therapeutic agent, no hypoglycaemia.
 To hold : no evidence
 The risk of lactic acidosis in patients taking metformin is
very low, but is more likely in those with renal impairment.
 Safe to coninue : except in:
1. pre-existing renal imp or significant risk of developing
AKI. (renally excreted and RF may lead to high plasma
levels - risk of lactic acidosis )
2. Use of contrast
 Recommended by NHS , JBDS, AAGBI 2015

42.  HA1C: optimum control- elective surgery
 Sliding scale : replaced by VRIII or basal- bolus
 Tight glycemic control ???
 Frequent intra-operative CBG monitoring
 Early resumption of normal diet
 Metformin: continued except in??
 RL : safe
 D5% should be avoided
 D5 – 0.45 NS with KCL : substrate solution

43.  Diabetes mellitus is likely to be the most common
comorbid factor encountered in Surgical practice.
 The main peri-operative concern in diabetic
patient is optimum glycemic control.
 A clear understanding of the metabolic process,
well controlled glycemic regimens and excellent
periop care will go a long way towards
decreasing the mortality and morbidity in
diabetes patients.