There are 3 main indications for a VRIII

• NBM Type 1 Diabetes >1 missed meal

• Type 1 Diabetes with recurrent vomiting (exclude DKA)

• Type 1 or 2 Diabetes & severe illness with need to achieve good glycaemic control

• Continue the patients’ usual basal subcutaneous insulin whilst on the VRIII

  Review the VRIII frequently to ensure:

• Correct rates of infusion are achieving target glucose levels.

• CBGs are being checked hourly

• Hypoglycaemia is treated promptly. Ensure that the VRIII is restarted as soon as a CBG>4 is confirmed – ideally within 20 minutes of the VRIII having been stopped to prevent rebound hyperglycaemia and possible ketosis

Use of a VRIII beyond 24 hours is rarely required - ensure that you review the need for the VRIII at least daily

This is a controlled document. If you are using a printed copy, check it against the guidelines site to ensure you are using the latest edition. Print copies must be destroyed after use.

Abbreviations

As many as 1 in 5 hospital inpatients have diabetes. Many will have been admitted as a medical emergency, often with diabetes as a secondary diagnosis.

Evidence suggests that if the blood glucose is not controlled, the outcome for the patient, measured by mortality, morbidity or length of stay, is worse.

In the acute setting, the options for controlling blood glucose are limited. In a patient that is eating and drinking, better glycaemic control may well be achieved by the use of subcutaneous insulin but this requires a degree of expertise. If the diabetes team is not available to advise and the patient is acutely unwell with a high blood glucose or nil by mouth, then the method of choice would be a VRIII – previously known as a sliding scale.

The emphasis throughout this guideline is on the safe use of a VRIII when clinically indicated, aiming for target blood glucose levels between 6-10mmol/L. It should be used for as short a duration as possible, with plans for a safe and effective step-down to other agents as soon as the clinical situation allows.

We have created a VRIII order set, accessible via the orders tab. This should make it easier to place all necessary orders at once. Please use alongside this guideline.

1. NBM Type 1 Diabetes >1 missed meal

2. Type 1 Diabetes with recurrent vomiting (exclude DKA)

3. Type 1 or 2 Diabetes & severe illness with need to achieve good glycaemic control e.g. Sepsis

For ACS, Stroke, TPN/Enteral feeding, Steroids and Pregnancy follow local guidelines and seek advice from the diabetes team.

CBG in range 6.0-10.0mmol/L

Avoid hypoglycaemia (CBG <4.0 mmol/l)

Limit use to < 24 hours where possible

Try to avoid using in those patients able to eat and drink

1. Withhold usual diabetes treatment during the VRIII BUT CONTINUE the basal insulin (see Table 1)

2. Prescribe the VRIII + fluids to go with this (see Tables 2 & 3)

3. CBGs must be monitored hourly whilst the VRIII is in use

4. Review the patient within 6 hours to make sure that CBGs are in target range – IMPORTANT

a. If not, ask yourself

i. Is the infusion running as prescribed? (check lines are patent and the infusion fluid is correct)

ii. Do I need to adjust the insulin infusion rate?

1. For CBGs persistently above 12 mmol/L and NOT falling

a. Upgrade the scale and review again within 6 hours

b. Check ketones 4 hourly

2. For CBG < 4 mmol/L i.e. hypoglycaemia

a. Stop the VRIII and treat the hypo as per local hypo guidelines

b. NOTE the VRIII should generally not be stopped for > 20 minutes so look to restart when the CBG is confirmed >4

c. STEP DOWN to the next scale when the VRIII is restarted – if you are already using the lowest pre prescribed scale, then use the customised section to downgrade further

d.  Review again within 6 hours

5.Check electrolytes daily (at risk of hyponatraemia and hypokalaemia)

6.Review the need for the VRIII at least once daily – if not sure, ask the diabetes team for help

7.Review the fluid status daily is your patient dehydrated or at risk of fluid overload (see table 3)

Stopping the VRIII

8. Ensure

a. The patient is able to eat and drink

b. CBGs are ideally <12mmol/L

c. That discontinuation takes place at a mealtime (preferably breakfast or lunch but evening meal is acceptable)

9. For

   a. Insulin treated patients – Basal (long acting) insulin should have been continued, if not, this MUST be given prior to discontinuation of the VRIII. Give rapid acting insulin with the meal and then stop the VRIII 30 minutes later.

   b. CSII (insulin pump) treated patients – involve the diabetes team. Reconnect the CSII, start the normal basal subcutaneous regimen, give a bolus dose of insulin with the meal and then stop the VRIII 30 minutes later. Please refer to online CSII guidance.

   c. Non insulin treated patients – restart usual treatment. Ensure that no contra-indications to the previous glucose lowering therapy have arisen (see Table 4 overleaf)

10. Check

a. CBG one hour after discontinuing the VRIII and 4 hourly for the next 24 hours to ensure there is no rebound hyperglycaemia. If the blood glucose rises, do not recommence the VRIII unless the patient is clinically unwell.

1. If you are unable to achieve CBGs within target range

2. If your patient requires a VRIII for > 24 hours

3. If diabetes control was suboptimal prior to admission (i.e., recent pre-admission HbA1c >58mmol/mol)

Advice for insulin treated patients

If the patient is on a basal insulin, this must be continued alongside the VRIII.

If the basal insulin was omitted in error this must be restarted before the VRIII is discontinued.

If the basal insulin is not due for several hours & you want to stop the VRIII (e.g., at breakfast or lunch) then give half the usual dose of basal insulin along with the meal and a dose of rapid acting insulin. This will give essential background insulin until the usual dose can be recommenced.

Advice on when to change the prescribed infusion rate

Review patients within 6 hours of starting a VRIII to ensure CBGs are in target range

Aim is for a target CBG between 6-10 (5-12 acceptable)

If CBGs 6-10 – no need to change the VRIII insulin infusion rate

If CBGs above target but still falling – no immediate change required but check again in 6h

If CBGs above target and not falling – upgrade the insulin infusion rate to the next scale, e.g., if using ‘standard rate’ you would upgrade to the ‘increased rate’ scale. If already using the ‘increased rate’ scale you would write up a new (further increased) scale in the customised scale section.

Prescribe

1Litre 5% glucose with 40 mmol KCl to run at 125ml/hour (exception to this would be if the patient’s starting blood glucose was ≥15 mmol/L when you would prescribe 1 Litre of 0.9% N/Saline with 40 mmol KCl to run at 125ml/hour). Once the patient’s blood glucose has fallen to <15 you should then switch to 5% glucose as above and continue with this as the fluid of choice. If the patient’s blood glucose subsequently rises above 15 the VRIII scale should be upgraded to get better control but there would be no need to change back to 0.9% N/Saline. Do monitor the Sodium and Potassium daily.

Note

If the patient’s potassium is >5.5 mmol/L - no KCl is to be added to the infusion fluid.

If the patient’s potassium is <3.5 mmol/L – senior review needed as extra potassium needs to be given.

Caution in those with eGFR <20ml/min- may need less potassium + extra monitoring of K 8 hourly

You must take into account the patient’s individual circumstances in terms of fluid requirements.

Dehydrated patient

Additional fluid required usually in the form of Plasmalyte. This can run alongside the glucose infusion.

Frail elderly patient at risk of fluid overload

Reduce infusion fluid rate to 83ml/hour i.e. 2 litres per 24 hours

Patients with severe heart or renal failure

May not be able to tolerate standard volumes of fluid. It may be necessary to use 10% glucose instead. This should be prescribed as 500 ml of 10% glucose with 10 mmol KCl to run at 42 ml/hour (this infusion fluid is available from G9 and Ward 4, G4 and ward 5, MADU (both sites), ITU (both sites), A&E Resus (both sites), AMU and AAU.

We would generally not recommend that a VRIII is run without any supplementary fluids; but if this is deemed necessary by a senior clinician (in exceptional circumstances), then monitoring of CBGs MUST take place on an HOURLY BASIS for reasons of safety.

Dose of sulphonylureas (eg gliclazide) may need to be reduced if food intake is likely to be limited

Metformin should only be recommenced when the eGFR is >30 ml/min. Reduce the dose to 500 mg bd if the eGFR is <45 ml/min. Avoid in severe heart failure.

Review the GLP-1 and DPP-4 inhibitors if the patient was admitted with suspected pancreatitis – this is a contra indication to them being restarted

Review the glitazone (Pioglitazone) therapy if the patient was admitted with heart failure or lower limb fracture or has known macular oedema – would want to avoid this medication in these circumstances

Review the SGLT-2 therapy if the patient was admitted with a urogenital infection. Defer the SGLT-2 inhibitor restart until any acute infection has been treated and the patient is eating and drinking. Do not restart if the patient came in in DKA.

Contact details for Diabetes team advice