QuestionSBA
QuestionChoice
After an operation, a patient should continue with an insulin-glucose infusion until they can tolerate at least 50% of their usual diet
32983
a
When she starts to eat normal meals
QuestionChoice
There is no timed cut-off period for re-starting insulin postoperatively
32986
d
24 hours postoperatively
QuestionChoice
Insulin-glucose infusions should be continued whilst the patient is only able to tolerate clear fluids. The patient's normal insulin regimen should be re-started once they can tolerate at least 50% of their usual diet
32984
b
When she starts to drink small amounts of fizzy drinks
QuestionChoice
There is no timed cut-off period for re-starting insulin postoperatively. Each patient will be different, for example, they may experience a post-operative infection or post-operative ileus, or they may be taking opioids postoperatively. All of these may affect their appetite, which will, in turn, affect when they should re-start their insulin
32985
c
12 hours postoperatively
QuestionChoice
There is no timed cut-off period for re-starting insulin postoperatively. Patients may be able to tolerate at least 50% of their usual diet before they are discharged. This should, therefore, not affect when they re-start their insulin
32987
e
On discharge
Concept
Chapter
# COPD

Patients with COPD are at higher risk of post-op complications than other patients because of their impaired respiratory function. It is therefore advisable to arrange the following tests before surgery:

- Lung function tests
- Chest x-ray
- Arterial blood gas (if the patient is known to retain carbon dioxide)

Furthermore, it is prudent to encourage patients to give up smoking before the operation and to start chest physio early after the operation.

# Drugs to stop

- **Cardiovascular drugs:** Clopidogrel should be stopped 7 days before surgery, warfarin should be (generally) stopped 5 days before surgery and instead patients should be on low molecular weight heparin until the night before, ACE inhibitors should be stopped the day before surgery.
- **Combined oral contraceptive pill** should be stopped 4-6 weeks before surgery, and re-started at least 2 weeks after surgery (when the patient is mobile). This reduces the risk of DVT.

# Patients taking steroids
When the body experiences acute stress (e.g. illness, trauma, surgery), the steroid demand increases. 

Patients on long term steroids cannot respond to this demand because their adrenal function is suppressed.

Therefore, patients who are on long term steroids usually need more steroids than usual during periods of physiological stress e.g. surgery or acute illness.


## Management

Peri-operative management is as follows:

1. Switch oral steroids to 50-100mg IV hydrocortisone.
2. If there is associated hypotension then fludrocortisone can be added.
3. For minor operations oral prednisolone can be restarted immediately post-operatively. If the surgery is major then they may require IV hydrocortisone for up to 72 hours post-op.

# Diabetes
Peri-operative management of diabetes, both non-insulin-dependent (type 2 diabetes) and insulin-dependent (type 1 diabetes), involves careful monitoring and adjustment of medication regimens to mitigate the risk of peri-operative complications. The need for specific peri-operative management in diabetics arises due to physiological changes in response to stress (such as surgery), combined with the patient's underlying metabolic disorder. Surgical stress can induce hyperglycemia, and alterations in medication timing or dosage may be necessary due to fasting or changes in renal function.

## Potential complications

-   **Hyperglycemia**: Characterised by blood glucose levels >180 mg/dL, symptoms include polyuria, polydipsia, and unexplained weight loss.
-   **Hypoglycemia**: Characterised by blood glucose levels <70 mg/dL, symptoms include palpitations, tremor, sweating, anxiety, and confusion.
-   **Diabetic Ketoacidosis (DKA)**: Common in type 1 diabetics, symptoms include polyuria, polydipsia, nausea, vomiting, abdominal pain, and fruity-smelling breath.
-   **Lactic Acidosis**: A potential complication of metformin use, especially in renal impairment. Symptoms include abdominal discomfort, nausea, vomiting, muscle pain, and rapid breathing.


## Management


| Drug | Plan |
| ---------------------------- | ---------------------------------------------- |
| Metformin (taken once daily) | Take during the morning of surgery |
| DDP-IV inhibitors | Take during the morning of surgery |
| GLP-1 analogues | Take during the morning of surgery |
| SGLT-2 inhibitors | Omit the day of surgery due to the risk of DKA |

For insulin-dependent diabetics, key principles are:

1.  Schedule the patient as early on the theatre list as possible, minimising the amount of time the patient is nil by mouth.
2.  If on long-acting insulin, this should be continued but reduced by 20%.
3.  Stop any other insulin and begin sliding scale insulin infusion from when the patient is placed nil by mouth.
4.  Continue infusion until the patient is able to eat post-operatively.
5.  Switch to the normal insulin regimen around their first meal.

*For some operations (particularly those that do not require contrast media) metformin does not need to be stopped, but one should always consider the risk of lactic acidosis.

After surgery, all oral medications should generally be restarted the morning following surgery.



# NICE Guidelines

[NICE Guidelines on Diabetes management during the Peri-operative period](https://bnf.nice.org.uk/treatment-summaries/diabetes-surgery-and-medical-illness/)
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5406
Peri-operative Medication Optimisation
Topic
7
General Surgery
6597
An 48-year-old female was admitted to hospital due to central umbilical pain, which then moved to the right iliac fossa. She underwent an appendectomy. She has a past medical history of obesity, hypertension and type 2 diabetes mellitus. After the operation, she is started on an insulin-glucose infusion.

When should she re-start her usual insulin medication?
a