Perioperative glycaemic control in insulin-treated type 2 diabetes patients undergoing gastric bypass surgery

Neth J Med. 2014 May;72(4):202-9.


Background: Roux-and-Y gastric bypass (RYGB) rapidly reduces insulin requirements in patients with insulin-dependent type 2 diabetes mellitus (T₂DMi). A too modest reduction in insulin dose may lead to hypoglycaemia in the early postoperative period.

Objective: To evaluate a regimen designed to maintain blood glucose levels between 5-15 mmol/l and to prevent hypoglycaemic events (blood glucose <3.5 mmol/l) after RYGB surgery.

Design: The effect of a 75% reduction in insulin dose was studied in 85 T₂DMi patients during the first ten days after RYGB. Patients with severe b-cell failure (fasting C-peptide <0.3 nmol/l) were excluded.

Primary outcome measures: percentage of patients exceeding the upper or lower blood glucose limits, and the number of hypoglycaemic events.

Results: The mean blood glucose level was 12.4±0.3 mmol/l (mean ± SE) on the day of surgery (day 0), 10.7±0.3 mmol/l on day 1, 10.0±0.5 mmol/l on day 2, and 8.3±0.3 on day 10. Of all measurements performed during this ten-day period, 12.4% were above the target range, and 2.6% were <5 mmol/l. There were no hypoglycaemic events during the stay in hospital. During the first week at home 2% of the measurements were <3.5 mmol/l.

Conclusion: A 75% reduction in insulin dose is safe in T₂DMi patients without severe b-cell failure, and prevents hypoglycaemia in the early postoperative period of RYGB in most cases.

Publication types

  • Observational Study

MeSH terms

  • Blood Glucose / drug effects
  • Blood Glucose / metabolism*
  • C-Peptide / blood
  • Diabetes Mellitus, Type 2 / blood*
  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Drug Administration Schedule
  • Female
  • Gastric Bypass / adverse effects
  • Glucose / administration & dosage
  • Humans
  • Hypoglycemia / etiology
  • Hypoglycemia / prevention & control*
  • Hypoglycemic Agents / therapeutic use
  • Insulin / administration & dosage*
  • Insulin / adverse effects
  • Male
  • Middle Aged
  • Obesity, Morbid / complications
  • Obesity, Morbid / surgery*
  • Perioperative Period
  • Time Factors


  • Blood Glucose
  • C-Peptide
  • Hypoglycemic Agents
  • Insulin
  • Glucose