Diabetes management after bariatric surgery
Diabetic patients undergoing bariatric surgery often experience major improvements in blood glucose control
before weight loss occurs, and even before discharge from the hospital (1). Protocolized management of
diabetes in the immediate post-operative period has been shown to reduce post-op complications, and
treatment with a sliding scale, basal insulin, and metformin has been shown to increase the percentage of
patients experiencing diabetic remission at one year (2).
Guidelines for diabetes management after bariatric surgery
During admission:
 Avoid dexamethasone
 Do not give dextrose-containing fluids to diabetics. For post-operative IV fluids, use normal saline or half
normal saline
 Hold metformin during the hospitalization but remember to restart it at time of discharge
 Start low dose Lispro sliding scale insulin Q4H
 If a patient has 3 blood glucose values > 180 mg/dL while on sliding scale, start basal insulin (Lantus)
o 0.1 U/kg is safe in almost all patients (BW of 100kg equals 10 U Lantus)
o Consult Endocrinology
At the time of discharge:
 All patients with a preoperative diagnosis of type 2 diabetes should be discharged on metformin
immediate release formulation, 1000 mg PO BID crushed, unless contraindicated due to intolerance or
comorbidity (i.e. chronic kidney disease)
 If a patient needed the initiation of Lantus during the admission, they should be discharged on Lantus, and
titrate the dose based on fasting glucose levels and the Lantus protocol below (this protocol is available on
the bariatric floors and nurses are familiar with it)
 Follow up in 2-4 weeks with endocrinologist or PCP
 Follow up hemoglobin A1c every 3 months.
 Metformin can be discontinued at 3-month follow up appointment if fasting blood glucose is <100 mg/dL
and A1c is <5.7%.
(1)
(2)
Schauer PR et al. Effect of laparoscopic Roux-en-Y gastric bypass on type 2 diabetes mellitus. Ann
Surg 2003
Fenske WK et al. Can a Protocol for Glycaemic Control Improve Type 2 Diabetes Outcomes After
Gastric Bypass? Obes Surg 2012
Lantus/Levemir Insulin Adjustment (BARIATRIC)
Insulin Dose Scale:
After surgery discharge instructions:
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Check fasting AM blood sugar after waking,
before eating or drinking anything and write
down on “Sugar and Insulin Log”
Determine insulin dose based on the “Insulin Dose
Scale” and write dose down on “Sugar and Insulin
Log”
Insulin should be given at the same time everyday
Follow up in 2-6 weeks with Dr. Rometo at the
Falk Diabetes Clinic. Schedule by calling 412-5869780
Have glucose tablets on hand in case of low blood
sugar <70. Take 4 and retest in 15 minutes
 Call the Falk Diabetes Clinic with
questions/concerns, or diabetic
supply needs at 412-586-9700
If fasting AM
blood sugar is
>220
180-220
144-179
120-143
100-119
81-99
72-80
<72
Adjustment compared to
dose given YESTERDAY
Increase by 6 units
Increase by 4 units
Increase by 2 units
Increase by 1 unit
No change. Take
YESTERDAY’S dose
Decrease by 2 units
Decrease by 4 units
Decrease by 6 units
Starting dose of insulin: ___units
Sugar and Insulin Log:
Date
Fasting AM Blood Sugar
(before you eat or drink)
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Insulin dose for today
(adjust from yesterday’s
dose based on fasting
AM blood sugar)