Anaesthetic management

1. Preoperative assessment and optimization

• Establish type of diabetes, duration, usual glucose values, HbA1c, current treatment, insulin regimen/pump, episodes of hypoglycaemia, DKA/HHS, and diabetic complications.
• Check capillary blood glucose on arrival. Obtain HbA1c if not available, though surgery should not be delayed solely for this unless control is very poor or metabolic decompensation is suspected.
• Check electrolytes, renal function, urine ketones or blood ketones when indicated, ECG, and full blood count.
• Schedule as the first case to minimize fasting disruption. Miller's Anesthesia, 10e, p. 3964.

• Record supine and standing BP, pulse, and symptoms of postural dizziness/syncope.
• Look for resting tachycardia, fixed heart rate, exercise intolerance, arrhythmias, and previous unexplained hypotension under anaesthesia.
• Assess for silent coronary disease: ECG for all; obtain echocardiography or cardiology review if symptoms, poor functional capacity, heart failure, abnormal ECG, or high cardiac risk.
• Review antihypertensives, diuretics, and drugs used for orthostatic hypotension. Avoid preoperative dehydration.

• Ask specifically about early satiety, bloating, reflux, nausea/vomiting, and known gastroparesis.
• Treat symptomatic gastroparesis as a high aspiration-risk state. Consider non-particulate antacid, H2 blocker/PPI, and metoclopramide where appropriate, with rapid-sequence induction if general anaesthesia is used.

• Omit short-acting meal-related insulin while fasting, but do not omit basal insulin completely, especially in type 1 diabetes.
• Withhold oral hypoglycaemic drugs according to local protocol.
• SGLT2 inhibitors need advance cessation because of perioperative euglycaemic ketoacidosis risk. Check ketones if unwell, acidotic, or glucose is unexpectedly raised.
• For GLP-1 receptor agonists, assess symptoms and aspiration risk, particularly delayed gastric emptying. Current guidance is risk-based rather than a uniform withholding rule.

2. Intraoperative plan

Monitoring and access

• Standard ASA monitoring plus frequent non-invasive BP cycling from before induction.
• Insert a radial arterial line before induction or immediately after it in significant autonomic dysfunction, expected major blood loss, labile BP, or major cardiovascular/renal disease.
• Two large-bore IV cannulae, group and cross-match blood, active warming, urine output monitoring.
• Check glucose at induction and at least hourly during major abdominal surgery or while receiving insulin infusion.

Glycaemic management

• Aim to avoid both hypo- and hyperglycaemia. A practical intraoperative target is approximately 100-180 mg/dL (5.6-10 mmol/L), allowing modestly higher values rather than inducing hypoglycaemia.
• For a prolonged open hysterectomy, insulin-treated diabetes, poor preoperative control, or glucose persistently above target, use a variable-rate IV insulin infusion with dextrose-containing fluid and potassium monitoring according to institutional protocol.
• Never rely on symptoms to detect hypoglycaemia in an anaesthetized patient. Confirm with point-of-care blood glucose testing.
• Continuous glucose monitors can be useful adjuncts but should not replace validated point-of-care or laboratory glucose measurements intraoperatively. A recent systematic review found variable perioperative accuracy and supports confirmatory testing (Carlier et al., 2025).

Choice of anaesthesia

• Use careful titration of induction agents. Propofol can cause marked vasodilation and hypotension in autonomic neuropathy, so reduce dose and administer incrementally.
• Ensure adequate volume status before induction, but avoid indiscriminate fluid loading in patients with renal impairment or cardiac dysfunction.
• If gastroparesis or reflux is present, use aspiration prophylaxis and a modified rapid-sequence or rapid-sequence induction as clinically indicated.
• Avoid sudden reductions in sympathetic tone and avoid deep anaesthesia without haemodynamic support.
• Use short-acting, titratable opioids and a multimodal analgesic plan.

• A thoracic epidural can provide excellent analgesia and reduce opioid requirements, but sympathetic blockade can produce profound, poorly compensated hypotension in autonomic neuropathy.
• If used, insert and dose it incrementally, preferably with invasive BP monitoring and vasopressors immediately available.
• Epidural analgesia combined with general anaesthesia may be reasonable for open hysterectomy, but is not mandatory.

Haemodynamic management

• Establish a baseline BP and target near the patient’s usual pressure. Avoid sustained MAP reductions greater than about 20% from baseline.
• Treat hypotension early:
  1. Assess blood loss, anaesthetic depth, position, and volume status.
  2. Give small, reassessed crystalloid boluses if hypovolaemia is likely.
  3. Use direct-acting vasopressors early, such as phenylephrine or norepinephrine infusion/boluses, because indirect agents may be less predictable.
• Bradycardia may respond poorly because of vagal dysfunction. Have atropine, epinephrine, and pacing capability available if severe conduction disease is suspected.
• Maintain normothermia because thermoregulation may be impaired.
• Use meticulous positioning and padding because peripheral neuropathy increases pressure-injury risk.

3. Postoperative management

• Transfer to PACU with continued BP, ECG, oxygen saturation, temperature, and serial glucose monitoring.
• Consider HDU/ICU observation if there was major blood loss, vasopressor requirement, significant cardiac autonomic neuropathy, renal dysfunction, or poor glycaemic control.
• Restart basal insulin promptly and safely. Resume usual diabetes therapy only once oral intake is reliable and renal function is stable.
• Monitor for hypoglycaemia, hyperglycaemia, ketosis, electrolyte disturbance, acute kidney injury, ileus, nausea/vomiting, urinary retention, wound infection, and orthostatic hypotension.
• Use multimodal analgesia to facilitate mobilisation while minimizing opioid-related ileus and respiratory depression.
• Give standard venous thromboembolism prophylaxis, early mobilisation, and meticulous wound/pressure-area care.

Concise exam-style conclusion