Download Surgery In Diabetes Mellitus

Surgery In Diabetes Mellitus (DM)
Walid Sayed Abdelkader Hassanen
Specialist of internal Medicine
March 2010
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Surgery In Diabetes Mellitus
• Hyperglycemia leads to impaired wound
healing , deficient formation of granulation
tissue.
• The chemotactic , phagocytic, and bacterial
activity of the neutrophil is deficient , there is
impaired hormonal host defense mechanism
and abnormal complement function.
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Metabolic sequelae in a surgical patient
• Increased glycogenolysis
• Increased gluconeogenesis hyperglycemia
• Decreased glucose utilization:
Lipolysis with increased FFA
Protein breakdown
Increased nitrogen loss
Increased urea production
Increased sodium retension &
potassium execretion and alteration of water
metabolism ( increased ADH and increased
aldosterone secretion )
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Determinents of the management
plan
1. Type of DM
2. Treatment, diet, oral antidiabetic drugs,
insulin
3. Metabolic status
4. Vascular status: cardiac, renal, cerebral
5. Surgery:
Type: emergency or elective
Minor or major procedure
Type of anesthesia
Post operative oral intake
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Pre-operative management
• Metabolic stress of surgery and anesthesia cause
increased elaboration of catecholamins,
glucocorticoids, glucagon, and growth hormone,
all producing their metabolic effects resulting in
hyperglycemia in the pre-operative period.
• The glycemic control is aimed to achieve a
fasting plasma glucose of < 140 mg % and post
prandial plasma glucose of < 200 mg %.
• Insulin dependent diabetic patients can be
admitted 2-3 days prior to surgery to achieve
satisfactory control.
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Cont.
• In NIDDM patients if the control is good with
oral antidiabetic drugs , these drugs are
stopped on the day of the surgery and
intravenous fluids and insulin are given , if not
are advised to stop drugs one week before
surgery and admitted for insulin therapy.
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Subcutaneous insulin therapy
after admission
• When the fasting plasma glucose is 140 mg % to
give 4 units of soluble insulin subcutaneously
before breakfast and then monitor before lunch
blood sugar , if the pre- lunch blood sugar is
around 140 mg % it is advisable to give the same
4 units soluble insulin pre- meal.
• For every 40 mg rise in pre- meal blood sugar ,
pre-meal one unit of soluble insulin is added to
the previous dose of pre-meal insulin
• If the blood sugar level is more than 300 mg %
15 units of soluble insulin pre-meal three times a
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day is tried.
Practical aspects
1. In a few diabetics it is difficult to control
fasting plasma glucose with pre-meal bolus
soluble insulin, this situation requires
addition of small dose of intermediate acting
insulin at bed time.
2. In a few NIDDM patients the blood sugar can
not be controlled only with insulin, adding
small doses of oral antidiabetic drug is
rationale as this overcomes the resistance, on
the day of surgery oral drugs are stopped.
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On the day of surgery
• It is preferable to take diabetic patients for
surgery in the morning as first case.
• Normally the requirement of insulin is 0.3 U to
metabolize 1gm of glucose.
• When FPG < 120 mg % no insulin is given
except 5% glucose.
• When FPG 120- 160 mg % 5 % glucose with 5
units soluble insulin.
• For FPG 160- 200 mg % 5 % glucose with 8 U
of soluble insulin.
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Cont.
• If FPG crosses 200 and < 250 mg % 5 %
glucose with 10 U of soluble insulin.
• Values between 250- 300 mg % to give normal
saline with 6-8 U .
• If the blood sugar > 300 mg % 8-10 U are added
to normal saline and surgery is delayed for few
hours till satisfactory glycemic control is
achieved.
• All the above infusions are given at the rate of
100-120 ml / h .
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Post operative management
• With the resumption of oral feeds
subcutaneous insulin can be started, NIDDM
patients can resume their oral antidiabetic
drugs after week if there is no complications of
surgery.
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Intravenous fluids
1. Dextrose saline / normal saline is used if blood
pressure is low or normal.
2. If there is hypertension half normal saline or 5
% dextrose is given.
3. For normal metabolism 50 gm glucose is
required every 8 hours for energy and to avoid
ketosis, to meet this demand at least 1000 cc 5
% glucose every 8 h will be required.
4. In situations requiring fluid restriction 10 %
dextrose can be infused instead of 5 % with
double the dose of insulin.
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Practical aspects
1. Whatever is the pattern of infusion, the blood
sugar has to be checked every tow hours and
the flow rate is adjusted.
2. Intra and post operative potassium
monitoring is done and corrected
appropriately.
3. A few hours after surgery there will be
reduction in the insulin requirement as the
elevated counter hormones due to surgical
stress decline.
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Emergency surgery
• In emergency surgery it is deal to use
intravenous insulin infusion.
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Minor surgery
• For minor surgery the antidiabetic drugs and
insulin are stopped on the day of surgery, once
the surgery is over and the patient is permitted
to resume oral feeds the antidiabetic drugs are
started with half the dose which the patient was
originally taking, on the second post operative
day full dose of the oral drugs and or insulin
are started.
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Special situations
1. Blood sugar may rapidly fall after surgical
drainage of an infected area.
2. Type 2 diabetes can be safely switched over to
oral drugs after a week.
3. In coronary artery bypass surgery and
during and after renal transplantation the
insulin requirements will be exceptionally
high.
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Our aim
• To make patients safe for surgery, for this we
need an understanding team work between the
surgeon, anesthetist and diabetologist.
• When the patient is under anesthesia the ideal
is to have diabetic therapy supervised by a
diabetic team where available.
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THANK YOU
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