Rationale
Guidelines on the management of diabetes for procedures that lasts no longer than four hours and requiring periods of fasting.
Expected Objectives / Outcome
To provide guidelines for practitioners and patients on the safe management of diabetes before and during minor procedures. To minimise possible adverse events such as: hypoglycaemia, diabetic ketoacidosis, physiological instability, extended hospital stay and poor procedural outcomes.
Target Blood Glucose Levels between 5 to 10 mmol/L.
Indications:
Adults: age greater or equal to 16 years of age
Patients undergoing minor procedures (less than 4 hours) requiring fasting (not to miss more than one meal, unless it pertains to colonoscopy). Includes: gastroscopy, colonoscopy, radiological procedures, and minor surgery
This information provides a clinical guideline only. Further discuss with the diabetes team which includes:(Endocrine Registrar, Endocrinologist and Diabetes Educators) should be considered where there is uncertainty or special circumstances.
Contraindications:
Labour and Birth - please refer to Diabetes in Pregnancy Management CPP0591 and Insulin Glucose Infusions During Labour and Birth CPP0625.
Definitions
Types of insulin
Issues To Consider
Contraindications:
Major surgery- surgery more than 4 hours or more than one missed meal.
Pregnancy- see Diabetes in Pregnancy guidelines- Diabetes in pregnancy- management of type 1 diabetes
Age less than 16 years of age
Key points:
If possible, postpone elective surgery, if the glycaemic control is poor e.g. HbA1c greater than 70 mmol/mol/9%.
Discuss with diabetes team which includes(Endocrinologist, Endocrinology Registrar, Diabetes Educators) if the patient has poor glycaemic control (> 70 mmol/mol) or has frequent hypoglycaemic episodes. Omitting medications or reducing insulin as per guidelines may have serious consequences in these patients
Blood Glucose levels (BGL) should be kept between 5-10 mmol/L during the perioperative period.
During the procedure BGL should be tested 1 hourly.
Patients on insulin, test 3-4 hourly after procedure, when the patient is eating and drinking. If BGL are above 12 mmol/L, test 1-2 hourly. If BGLs are less than 4 mmol/L, to treat as a hypoglycaemic event and test BGLs as per protocol..
Patients should be given a sick day guidelines and clear action plan on what to do with insulin and/or non-insulin medications.
Management / Guideline
Fasting Patients on Insulin- Blood Glucose Level Monitoring Protocol
Blood Glucose Level Targets are between 5.0 and 10.0 mmol/L.
The intravenous insulin-glucose infusion protocol is recommended for major surgery, when the fasting period is anticipated to be prolonged or where poor glycaemic control is expected.
If the Insulin-Glucose Infusion is not used the following guidelines should be followed.
Patients on insulin undergoing fasting for surgery or diagnostic procedures MUST have their BGL tested at least two hourly.
If BGLs are between 4.0 and 6.0 mmol/L, test BGLs hourly.
Test BGLs hourly intraoperatively.
Medical officer to prescribe 1000 mL of 10% Glucose prior to fast, to treat hypoglycaemia and when bgl are <6 mmol/L.
If BGL is less than 4.0 mmol/L, call medical officer and treat hypoglycaemia with intravenous glucose, 100 ml of 10% Glucose or 10 mls of 50% Glucose.Thereafter start 10% Glucose at 40 mls per hour. If already on a Glucose infusion, this will need adjustment, call medical officer.
See CPP0268 Diabetes Mellitus Hypoglycaemia Management
If Blood Glucose level is <6.0 mmol/L start 10% Glucose at 40 mls per hour.
If BGL levels are > 15.0 mmol/L check for capillary ketones and contact medical officer if >0.6
If two BGL are >10.0 mmol/L- consult medical officer for correctional doses on insulin given q4 hourly
Suggested:
Table 1. Correctional Rapid-Acting Insulin Scale for Patients Fasting for a Procedure
Diabetes management guidelines for patients undergoing minor procedures (not more than one missed meal) excluding colonoscopy
Patients on non-insulin diabetes medication for procedures with no more than one missed meal (not including colonoscopy)
Table 2. Guidelines on the peri-operative management on non-insulin diabetic medication
*SGLT2 inhibitors have been associated with increased risk of Ketoacidosis (hyperglycaemia or euglycaemia) in Type 2 Diabetes patients undergoing stress procedures. The risks are very low and are yet to be fully elucidated. Patients often do not remember instructions for surgery, and if SGLT2 inhibitors were given within 24 hours of surgery, please liaise with the anaesthetist. Surgery may continue after clinical review but we suggest careful monitoring of BGLs and capillary ketones. If patients had been on subcutaneous insulin with SGLT2 inhibitors, starting an intravenous insulin-glucose infusion may be considered during and after surgery, if there are any concerns.
Tablets should restarted when the patient is eating and drinking normally. However Metformin can only be restarted if the eGFR is at baseline and is greater than 30 mLs/min
Patients on insulin and/or non-insulin diabetes medications for procedures with no more than one missed meal (excluding colonoscopy)
See table 2. for advice regarding non-insulin diabetes medication. For those on insulin see table 3. for guidelines on insulin adjustment for those undergoing procedures.
Note: Patient should take their usual dose of insulin (as well as non-insulin diabetes medication) on the day prior to surgery, and fasting usual begins at midnight.
Key points
For afternoon procedures, give a reduced dose of insulin in the morning in the form of intermediate or long-acting insulin, if possible
The medical officer organizing the procedure is recommended to write out the suggested insulin regimen on the day of the procedure; directly to the patient and in the medical notes
If BGL remains elevated, i.e. greater than 10 mmol/L, an Insulin-Glucose infusion is an option (refer to CPP0423 Diabetes - Insulin (actrapid) Glucose (I-g) Infusion For Adults).
Following the procedure, (those well enough to have lunch), a small amount (half of usual dose) of rapid-acting insulin can be administered before lunch
Table 3. Guidelines for the Peri-Procedure Adjustment of Insulin (No More Than One Missed Meal). See Definitions for information on the type of insulins.
Diabetes management guidelines for patients undergoing bowel preparation for colonoscopy
Key points:
Discuss with the diabetes team (Endocrinologist, Endocrinology Registrar or Diabetes Educators) if the patient has poor glycaemic control (greater than 70 mmol/mol) or have frequent hypoglycaemic episodes. Omitting medications or reducing insulin as per guidelines may have serious consequences in these patients
BGL monitoring should be performed more frequently, every 3-4 hourly during the day. If BGL are above 12 mmol/L, test BGL more frequently 1-2 hourly. If BGL is less than 5 mmol/L, patient to drink sugar containing clear drink such as clear fruit drink or soft drink (NO Diet or Zero options) to keep blood glucose levels above 5 mmol/L
Treat all patient on insulin as being insulin dependent, irrespective of the type of diabetes
Patient should be given an action plan of what to do, if they have a hypoglycaemic episode or persistent hyperglycaemia while on bowel preparation.
The medical officer organizing the procedure is to write out the suggested insulin regimen for bowel preparation and give this to the patient and document in the medical notes
Patients who have unstable diabetes should be admitted to hospital during the period of bowel preparation
Patients should be given a sick day guidelines and clear action plan on what to do with insulin and/or non-insulin medications
Guidelines on non-insulin diabetes medications while on bowel preparation while awaiting colonoscopy
DO NOT TAKE ANY ORAL NON-INSULIN DIABETES MEDICATION. DO NOT TAKE EXANATIDE OR LIRAGLUTIDE. Action Plan to be developed for the patient
Table 4. Guidelines on insulin management in diabetes patients undergoing colonoscopy and bowel preparation (see table 4 for information on the types of insulins)
References