NHS Tayside paediatric diabetes - managing T1D during surgical procedures

Remember, DKA can present in a similar way to an acute abdomen. In children with T1D who present acutely unwell, always check ketones and a blood gas.

If ketoacidotic:

• Follow guidelines on Diabetes Ketoacidosis (DKA).
• Operate when rehydrated, blood pressure is stable, blood gas is normal and electrolytes are within normal range.
• Blood or sensor glucose should ideally be stable between 5 and 11.1 mmol/l.  This may not be possible for some life-saving operations.

If not ketoacidotic:

• Diabetes management is dependent on surgery type and pump status - please select the appropriate heading below.

Minor procedures

Short procedures, with or without sedation/anaesthetic, rapid recovery expected with child eating and drinking soon after the procedure. E.g. endoscopic biopsies, incision and drainage.

Major procedures

General anaesthetic anticipated to last over 60 mins, procedures associated with post-operative nausea, vomiting or inability to eat and drink afterwards. Careful consideration should be given to admitting the CYP the day prior to major surgery.

As soon as the decision is made to proceed, the responsible surgeon/dentist should follow the relevant pre-assessment process and inform the diabetes team (via tay.diabetesouttheretayside@nhs.scot). Information should include:

• Date and timing of procedure (ideally, CYP with T1D should be first on a morning list).
• Type of procedure

Ideally, elective surgery should not be undertaken when glycaemic control is very poor (e.g. HbA1c >75mmol/mol OR Time in Range <36%). This can complicate recovery, particularly wound healing. Consideration should be given to optimising glycaemic control which may involve a hospital admission.

All CYP with T1DM should receive a pre-operative assessment, which can usually be undertaken by phone.

Key questions:

• Is glycaemic control acceptable? This can be assessed by asking parents, looking at the child’s most recent diabetes clinic letters on Clinical Portal and looking at their most recent HbA1c (target is <53mmol/mol). If in doubt then ask the diabetes team for guidance.
• What is the CYP’s usual insulin regimen?
• How does the CYP monitor glucose? e.g. intermittent finger prick checks or continuous glucose monitor (CGM).

Clarify fasting instructions with the family:

Therefore a CYP on a morning list must omit breakfast but can continue to drink sugary fluids until 1 hour before the procedure to avoid hypoglycaemia. A CYP on an afternoon list can have an early morning breakfast (pre 0730) and omit lunch.

Blood glucose (BG) should be kept between 5-11.1mmol/l during the peri-operative period

BG should be checked at least hourly before during and after surgery using capillary blood glucose testing.

Sensor glucose (used alone or as part of a hybrid closed loop (HCL) system) should augment and not replace intraoperative BG monitoring, due to lack of evidence of reliability in the intraoperative setting.

Insulin pumps

Most CYP using a pump are using hybrid closed loop (HCL) technology.  HCL systems adjust basal rates of insulin every 5 minutes, in accordance with sensor glucose readings.  HCL systems are limited in how much automated insulin can be delivered and so users must still bolus insulin prior to eating, with dose dependent on carbohydrate content and sensor glucose level.

There are a variety of systems on the market including patch pumps (worn on the skin, e.g. Omnipod) and tethered pumps (pump connected to skin by tubing, e.g. Ypsopump).  The automated algorithms and modifiable settings vary by manufacturer - please contact tay.diabetesouttheretayside@nhs.scot for advice on specific models, if required.

Pre-op insulin

• Ask for the CYP’s average total daily dose (TDD) of insulin which can be obtained from pump.
• Most families can be advised to continue with their pump settings without any alterations. Ideally children should remain on their insulin pumps during surgery in full auto mode.  NB Pumps will limit/switch off auto mode in the event of sensor failure or lack of user interaction.
• If a child has very tight glycaemic control and/or has frequent hypoglycaemia, consider advising weaker pump settings, starting the night before and continuing for the day of surgery.  There are a variety of ways that this can be achieved, depending on manufacturer.  Please ask parents/carers or CYP to seek advice from the paediatric diabetes team if help required.
• When CYP are fasting, they should omit their pre-meal insulin bolus. E.g. if on morning list and omitting breakfast, they should not receive pre-breakfast bolus. If on afternoon list and having an early breakfast, they should receive a pre-breakfast bolus as usual, but omit their lunchtime bolus.

If in doubt then liaise with the paediatric diabetes team for advice about insulin dose adjustment.

Peri-op management

Ask families to perform a set/pod-change the day before surgery, ensure the pump battery is well charged up, and bring supplies to undertake an emergency set/pod change if required in hospital.

For younger CYPs, the parent/carer must agree to remain with them in hospital and take responsibility for operating the pump. This will not apply when actually in the operating theatre.

Blood or sensor glucose should be checked on arrival on the ward and every hour during stay (or earlier if child feels/looks unwell).

Consider placing an IV cannula pre-op. This may be required if child is anticipated to be fasting for several hours, or if their glucose readings are at the lower end of the acceptable range.

Actions required are based on glucose level:

The recommended approach to treating mild hypoglycaemia in CYP with HCL is to give 5g of quick acting carbohydrate every 5 minutes.  Small increments of carbohydrate are advised so as to avoid rapid increases in sensor glucose (resulting in increased automated insulin delivery).

Fluids containing 5g of glucose include:

• 50mls pure apple juice
• 50mls water with 5g added glucose powder
• Half 25g tube of glucogel.

IV glucose is given as 2mls/kg of 10% glucose.

If CYP has persistent BG readings below 5mmol/L, commence IV fluids (0.9% saline + 10% glucose) at maintenance rate and monitor closely.

Insulin correction is given as a pump bolus - dose as per individual correction factor (saved within pump settings) OR 10% of Total Daily Dose (TDD) of insulin.

If CYP has persistent BG readings >11mmol/L or has ketones >0.6 then consider removing pump and commencing IV insulin and fluids (see major procedures guidance).

Resume usual insulin regimen once able to eat and drink. CYP should be allowed home once tolerating oral intake.

Insulin pumps

Most CYP using a pump are using hybrid closed loop (HCL) technology.  HCL systems adjust basal rates of insulin every 5 minutes, in accordance with sensor glucose readings.  HCL systems are limited in how much automated insulin can be delivered and so users must still bolus insulin prior to eating, with dose dependent on carbohydrate content and sensor glucose level.

There are a variety of systems on the market including patch pumps (worn on the skin, e.g. Omnipod) and tethered pumps (pump connected to skin by tubing, e.g. Ypsopump).  The automated algorithms and modifiable settings vary by manufacturer - please contact tay.diabetesouttheretayside@nhs.scot for advice on specific models, if required.

Pre-op insulin

• Ask for the CYP’s average total daily dose (TDD) of insulin which can be obtained from pump.
• Most families can be advised to continue with their pump in auto mode with the current settings unless glycaemic control concerns.
• If a child has very tight glycaemic control and/or has frequent hypoglycaemia, consider advising weaker pump settings, starting the night before and continuing for the day of surgery.  There are a variety of ways that this can be achieved, depending on manufacturer.  Please ask parents/carers or CYP to seek advice from the paediatric diabetes team if help required.
• When CYP are fasting, they should omit their pre-meal insulin bolus. E.g. if on morning list and omitting breakfast, they should not receive pre-breakfast bolus. If on afternoon list and having an early breakfast, they should receive a pre-breakfast bolus as usual, but omit their lunchtime bolus.

If in doubt then liaise with the paediatric diabetes team for advice about insulin dose adjustment.

Peri-operative insulin

• The CYP’s usual insulin pump settings should continue up until the time of surgery.
• Blood or sensor glucose should be checked on arrival on the ward and every hour during stay (or earlier if child feels/looks unwell).
• Following induction of anaesthesia, the CYP should be cannulated and commenced on normal maintenance IV fluids and insulin infusion - see below for insulin infusion instructions.
• Discontinue/disconnect insulin pump infusion at time of starting IV insulin (NB parent/carer may be required for this).
• CYPs on IV insulin infusions should be nursed in HDU (or ward 30 if planned day case) until ready to recommence diet and subcutaneous insulin.
• Restart insulin pump prior to eating and discontinue IV insulin 10 minutes after pump restarts.

Insulin infusion

IV fluids and insulin should always run via the same IV cannula.

Dilute 50 units soluble insulin (Actrapid) in 50mls sodium chloride 0.9% to make 1 unit/ml solution.  The starting rate of the infusion depends on the child’s blood glucose (BG) reading:

• If BG between 5-8mmol/L, start 0.025 units/kg/hr
• If BG between 8.1-11 mmol/L, start 0.05 units/kg/hr
• If BG between 11.1-15 mmol/L, start 0.075 units/kg/hr
• If BG >15.1, start 0.1 unit/kg/hr.

Check BG every 30 mins intra-operatively and until the child recovers from anaesthesia. This can then he relaxed to every 60 mins.

The aim is to keep BG readings stable, within a range of about 3mmol/L up or down from the starting point. If BG is rising or falling outwith this range, always check your equipment is working correctly and then consider adjusting the insulin infusion rate.

If BG >12mmol/l for three consecutive readings and is not dropping by 3mmol/l/hr or more the rate of insulin infusion should be increased.

If BG <5mmol/l, stop the IV insulin infusion but only for 10–15 min. Give bolus of IV 10% glucose 2ml/kg; recheck BG 15 minutes later

Maintenance fluids

Fluid of choice = 0.9% saline + 5% glucose + 10mmol KCL/500ml bag.

Increase to 10% glucose if risk of (or ongoing) hypoglyclaemia.

Maintenance infusion rate as per normal paediatric calculation.

Pre-op insulin

• Ask for the CYP’s average total daily dose (TDD) of insulin, this is the total basal and bolus added together. This is likely to vary slightly day to day.
• Most families can be advised to give the usual dose of basal insulin (i.e. Lantus or Tresiba) at the usual time of administration.
• When CYP are fasting, they should omit their bolus insulin which would generally be given at that mealtime. E.g. if on morning list and omitting breakfast, they should not receive breakfast time novorapid. If on afternoon list and having an early breakfast, they should receive breakfast novorapid as usual, but omit their lunchtime dose.
• If a CYP has very tight glycaemic control and/or has frequent hypoglycaemia, consider advising a 20% reduction to basal insulin the day before the operation.
• Likewise, if the CYP is on an afternoon list and thus having breakfast novorapid, consider whether the dose should be reduced by 20%.

If in doubt then liaise with the paediatric diabetes team for advice about insulin dose adjustment.

Peri-op management

Blood or sensor glucose should be checked on arrival on the ward and every hour during stay (or earlier if child feels/looks unwell).

Consider placing an IV cannula pre-op. This may be required if child is anticipated to be fasting for several hours, or if their glucose readings are at the lower end of the acceptable range.

Actions required are based on glucose level:

Oral glucose containing fluids include:

• 150mls pure apple juice
• 150mls water with 15g added glucose powder
• 25g tube of glucogel.

IV glucose is given as 2mls/kg of 10% glucose.

If child has persistent BG readings below 5mmol/L, commence IV fluids containing 10% glucose at maintenance rate and monitor closely.

Insulin correction is given as Novorapid - dose as per individual correction factor OR 10% of Total Daily Dose (TDD) of insulin.

If child has persistent BG readings >11mmol/L or has ketones >0.6 then consider commencing IV insulin and fluids (see major procedures guidance)

Resume usual insulin regimen once able to eat and drink. Child should be allowed home once tolerating oral intake.

Peri-operative insulin

• The CYP’s usual insulin regimen should continue up until the day of surgery. This includes daily administration of basal insulin.
• Blood or sensor glucose should be checked on arrival on the ward and every hour during stay (or earlier if child feels/looks unwell).
• The CYP should be cannulated and commenced on IV fluids and insulin infusion - see below for insulin infusion instructions. For morning list this should commence at 07:00, for afternoon list this should commence at 12:00.
• CYPs on IV insulin infusions should be nursed in HDU (or ward 30 if planned day case) until ready to recommence diet and subcutaneous insulin.
• Check that last dose of long acting insulin (e.g. glargine or degludec) has not been missed.
• Give rapid acting insulin prior to food, dose dependent on carbohydrate content (parent/carer to calculate).
• Stop IV insulin 10 minutes after subcutaneous rapid acting insulin has been given.

Insulin infusion

IV fluids and insulin should always run via the same IV cannula.

Dilute 50 units soluble insulin (Actrapid) in 50mls sodium chloride 0.9% to make 1 unit/ml solution.  The starting rate of the infusion depends on the child’s blood glucose (BG) reading:

• If BG between 5-8mmol/L, start 0.025 units/kg/hr
• If BG between 8.1-11 mmol/L, start 0.05 units/kg/hr
• If BG between 11.1-15 mmol/L, start 0.075 units/kg/hr
• If BG >15.1, start 0.1 unit/kg/hr.

Check BG every 30 mins intra-operatively and until the child recovers from anaesthesia. This can then he relaxed to every 60 mins.

The aim is to keep BG readings stable, within a range of about 3mmol/L up or down from the starting point. If BG is rising or falling outwith this range, always check your equipment is working correctly and then consider adjusting the insulin infusion rate.

If BG >12mmol/l for three consecutive readings and is not dropping by 3mmol/l/hr or more the rate of insulin infusion should be increased.

If BG <5mmol/l, stop the IV insulin infusion but only for 10–15 min. Give bolus of IV 10% glucose 2ml/kg; recheck BG 15 minutes later

Maintenance fluids

Fluid of choice = 0.9% saline + 5% glucose + 10mmol KCL/500ml bag.

Increase to 10% glucose if risk of (or ongoing) hypoglyclaemia.

Maintenance infusion rate as per normal paediatric calculation.