21st May 2025

Diabetes in Palliative Care and Surgical Settings

The management of patients with Diabetes Mellitus (DM) continues to be a demanding area of medicine. Diabetes impacts people throughout their lives, and treatments may need to be adapted in certain settings. Specifically, this chapter will look at managing diabetic patients in a surgical setting and during end of life (EOL) care.

Diabetes in a Surgical Setting

Over 15% of people having operations in the UK have diabetes and thus, their perioperative management can be challenging. The surgical setting often subjects patients to periods of being nil by mouth, resulting in erratic blood sugars. Management can be broadly split into three sections: Preoperative, Intraoperative, and Postoperative.

Preoperative care

During the preoperative assessment, it is important to identify the underlying type of diabetes, as this will influence the patient’s management plan. The most common types are bullet-pointed below:

• Type 1 DM 
• Type 2 DM and insulin-dependent (+/- non-insulin glucose-lowering medication) 
• Type 2 DM and on non-insulin glucose-lowering medication 
• Type 2 DM diet-controlled

Optimising diabetic control is known to improve surgical outcomes. Several investigations should be considered to assess an individual’s baseline diabetic control.

Investigations

• HbA1c – The patient should ideally have their HbA1c checked three months prior to surgery, allowing for prompt referral to the Diabetes specialist team for optimisation, especially if the HbA1c is >69mmol/mol (8.5%).  
• Blood Glucose Levels – The degree of metabolic derangement on presentation should be noted. This includes if the patient is known to have recurrent or severe hypoglycaemia, or persistent hyperglycaemia (defined as two or more consecutive BG values >13mmol/l or hyperglycaemia with ketone levels >1.5mmol/l).
• Blood Osmolarity, Ketones and Electrolytes – These should be checked to assess for evidence of Diabetic Ketoacidosis (DKA) and Hyperosmolar Hyperglycaemic State (HHS).

Clinical Management

Identify other comorbidities that often coexist with diabetes and refer to the relevant teams for optimisation where necessary e.g. hypertension, cardiac disease, renal disease etc.

Medication Management

A pharmacist should be consulted to ensure medication reconciliation before admission. Instructions regarding necessary changes to medication before admission should be discussed and given to the patient. The anticipated period of total fasting (from the last meal to the next meal) should be assessed, as this will alter whether variable rate insulin (VRIII) is required and for how long. Also, a pre-prescribe rescue treatment for hypoglycaemia should be prescribed as a precaution. 

• Insulin Therapies (Type 1 and Type 2 DM) – Insulin should not be omitted for patients with T1DM. However, if only one meal is likely to be missed, it may be possible to give a reduced dose of their usual insulin. If a prolonged operation and a significant starvation period is anticipated, a VRIII regime can be prescribed. A VRIII can also be considered for patients who have T2DM. The indications for VRIII are:
  1. Patients with insulin-dependent Diabetes, in which the anticipated/actual fasting period is greater than one missed meal.
  2. Patients with Diabetes and recurrent hyperglycaemia (CBG > 12mmol/l).
• Non-Insulin Therapies – The table below has been adapted from Diabetes UK and outlines the guidance for the common non-insulin therapies. It should be noted that each patient should be assessed on an individual basis.

Table 1: Guidance for non-insulin therapies

Other Considerations

Where possible, the urgency of the procedure and the possibility of postponement should be discussed, with a view to optimising the patient’s weight, diabetic control, and other comorbidities during the preoperative period. The patient should also be listed for a morning operation to reduce starvation time and the likelihood of delays. 

Intraoperative care

During the operation, it is essential to ensure a patient’s blood glucose level is monitored. Capillary blood glucose monitoring is the preferred modality, as it is easily obtainable and accurately reflects the patient’s arterial blood glucose levels. This is unlike continuous glucose monitoring, which often lags. The target blood glucose range should be kept between 6 and 10 mmol/l.

Blood sugars should be monitored at these frequencies as a minimum: 

• VRIII – Hourly (especially if sedated/anaesthetised, on subcutaneous insulin and on the day of surgery).
• Subcutaneous insulin (not fasted) – Three to four times a day.
• Non-insulin diabetic medication – Twice a day.
• Diet controlled and CBG <10mmol/l – Once a day.

If a patient is on a VRIII, a solution containing glucose, sodium and potassium should be run alongside to meet the routine maintenance requirements. If there are significant delays and the CBG is >13mmol/l, ketones should be checked.

Postoperative care

Following the procedure, monitor and maintain CBG (target 6–12mmol/l) unless otherwise specified in the patient’s care document. The main aim is to promote restoration of their usual diet and normal diabetes medications, with a caveat that doses may need to be adapted due to reduced appetite, nausea, and vomiting. Anti-emetics are encouraged, to avoid these unwanted side effects. In patients with T1DM, never stop an insulin infusion unless basal subcutaneous insulin has been given and ketones have been checked, to reduce the risk of hospital acquired DKA. Electrolytes and fluid balance should be monitored daily. Once a patient is optimised, ensure a proactive planned approach to a timely, safe, and effective discharge. The patient may require follow-up with their diabetic team.

References

• Joint British Diabetes Societies (JBDS) 2022 Guideline for Perioperative Care for People with Diabetes Mellitus Undergoing Elective and Emergency Surgery https://abcd.care/sites/default/files/site_uploads/JBDS_Guidelines_Current/JBDS_03_CPOC_Diabetes_Surgery_Guideline_Updated_2022.pdf
• Perioperative Diabetes. Highs and lows. NCEPOD 2018 https://www.ncepod.org.uk/2018pd.html
• Nice Perioperative Care in adults 2020 https://www.nice.org.uk/guidance/ng180/chapter/Recommendations#information-and-support-for-people-having-surgery

Diabetes in Palliative care 

Caring for people with diabetes as they approach EOL care can often be complex due to the variety of insulin and non-insulin therapies available. Mortality data shows that over 20% of patients each year have a form of diabetes. The management of diabetes in EOL care can be broadly split into three categories: 

• The last months of life 
• The final weeks of life
• The last days of life. 

These are discussed in more detail below.

Overview of the Medical Management

Patients with lifelong diabetes have often had to stick to stringent clinical targets to mitigate the risks of long-term micro and macrovascular complications. Understandably, if it becomes evident that a patient is approaching EOL, regular monitoring of blood glucose levels can be relaxed. This shift in treatment approach can often cause concern and distress. Therefore, engaging individuals and their families about how they want their care to transition as they approach EOL is essential. This process should be conducted with utmost sensitivity, emphasising that the primary goal of care should transition towards enhancing their quality of life. It necessitates comprehensive discussions on the adjustments required in their medical management. The sections below provide an overview of Non-Insulin Therapies, Insulin Therapies, and Continuous Subcutaneous Insulin Infusion (Insulin Pump Treatment).

Non – Insulin Therapies

During their lifetime, individuals with type 2 diabetes usually transition from diet control to requiring pharmacological treatment. Traditionally, first-line pharmacological management involves metformin; however, this may progress to utilising multiple agents in combination. The patient’s HbA1c levels guide the intensification of therapy. 

When a diagnosis indicates that an individual is reaching the end of their life, it becomes essential to re-evaluate their medication regimen. At this stage, the fundamental principles of drug management remain the same. Particular emphasis should be on optimising medication choices to minimise the side effects and improve quality of life. This includes balancing the risk of both symptomatic hyper- and hypoglycaemia. Additionally, it is crucial to consider factors such as the evolving burden of the disease, the individual’s diminished appetite, and the deterioration of renal and hepatic function.

Table 2: Common medication and risk of hypoglycaemia

Insulin therapies (Type 1 and Type 2 Diabetes)

Individuals diagnosed with type 1 diabetes have an absolute dependence on insulin therapy and should continue to have insulin despite being EOL due to their risk of developing diabetic ketoacidosis.

Conversely, most individuals with type 2 diabetes still maintain some level of endogenous insulin production, protecting them against ketoacidosis. However, they are at risk of developing hyperosmolar hyperglycaemic states, particularly if given corticosteroids.

As an individual’s health deteriorates and they approach EOL, a review of their insulin dosage becomes necessary, often resulting in a reduction. The occurrence of reduced appetite and declining body weight often prompts this adjustment. As food intake diminishes, fast-acting insulin can likely be discontinued, and basal insulin will suffice, even for people with type 1 diabetes.

It is recommended to initiate a conversation about target glucose levels and treatment objectives early to ensure that individuals and their families understand the likelihood of dose reductions.

Continuous subcutaneous insulin infusion (Insulin Pump Treatment)

Insulin pumps have become increasingly common amongst patients with type 1 diabetes because they provide better flexibility. However, as they rely on frequent capillary blood glucose testing and adjusting bolus doses according to the carbohydrate content of their food, they need monitoring and adjustment towards the EOL. Therefore, early involvement of the Diabetes Specialist Pump Team is required.

Managing diabetes in the last year to months of life

Recognising people in their last year of life is essential and allows meaningful conversations about what matters most to the individual. It means individuals can express their views and priorities about future care. During this time, stringent blood glucose targets should be relaxed. Although there is no published evidence for target glucose or HbA1c levels, Diabetes UK suggests;

• Aim 1 – no glucose level less than 6 mmol/l 
• Aim 2 – no glucose level higher than 15 mmol/l

It is essential to recognise that the optimal range will vary according to the stage of illness, the individual’s ability to eat and drink normally, the presence of hypoglycaemia, the nutritional status, and the treatments given. 

As an individual approaches their last year to months of life, complex regimens should be reviewed and rationalised. It is much easier for the patient to be on insulin alone rather than multiple combinations of oral hypoglycaemic agents alongside insulin. Insulin regimens should be simplified, e.g. changing from twice to once daily (long-acting) insulin, even in patients with type 1 diabetes.

Managing diabetes in the last weeks of life

During the last weeks of life, patients approaching EOL should have been identified. In keeping with the advice above, the patient’s medications should be rationalised and adjusted; however, there may be little time to get used to a new insulin regimen. Support should be sought from the diabetic team as help is often needed for dose adjustments, as well-being, activity and appetite can change daily. 

Also, choosing relaxing targets for control may seem like “giving up” for some patients and their families, whilst others may view managing diabetes in addition to their terminal illness as “futile”. The development of hypoglycaemia in people not previously prone to this is a poor prognostic sign.

The main aim of treatment here is to:

• Keep invasive tests to a minimum – look at the method and frequency of checking blood glucose levels. It is advisable to perform a single capillary blood test each day just before administering insulin to confirm that blood glucose levels fall within the desired range and to pre-empt the occurrence of hypoglycaemia.
• Be alert to hypo or hyperglycaemia symptoms and have appropriate medication/interventions available to address these if they develop. 
• Aim for a target blood glucose reading of 6-15mmol/L. 
• Rationalise the amount of medication needed to control their diabetes.

Managing diabetes in the last days of life

Ideally, by this point, diabetes treatment has been minimised so that few changes are required. Diabetes at end-of-life encompasses changes to: 

• Tailoring of diabetes medications

Table 3: Diabetes medications

• Glycaemic targets 

Table 4: Glycaemic targets

• Individual and carer expectations
• Reducing the risk of hyperglycaemia and hypoglycaemia 
• Managing the effects of other EOL medications, e.g. glucocorticosteroids

References

• Diabetes UK. End of life: Care Recommendations 2021 – https://diabetes-resources-production.s3.eu-west-1.amazonaws.com/resources-s3/public/2021-11/EoL_TREND_FINAL2_0.pdf
• NICE EOL care for adults: service delivery 2019 https://www.nice.org.uk/guidance/ng142/chapter/Recommendations#reviewing-current-treatment
• Palliative care: the Lase hours and days of life https://www.uptodate.com/contents/palliative-care-the-last-hours-and-days-of-life?search=diabetes%20in%20palliative&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1