Examqo › Examqo library › Anesthesiology › Perioperative medicine · IMLE
Endocrine disease around surgery
In diabetes glucose is kept at 100–180 mg/dL and basal insulin is never stopped in type 1 diabetes; long-term steroid users receive cover; in phaeochromocytoma alpha blockade comes before beta; and thyroid storm is treated as an emergency.
Why it matters in the exam
The exam asks about insulin and diabetes drugs on the day of surgery, the glucose target, who needs steroid cover and at what dose, and the preparation for phaeochromocytoma surgery — including the danger of giving a beta-blocker before an alpha-blocker. Other questions deal with thyroid storm during surgery (differential diagnosis with malignant hyperthermia), carcinoid syndrome and hypothyroidism that delays waking.
Perioperative hyperglycaemia increases infection, and hypoglycaemia in an anaesthetised patient is invisible — so glucose is measured often. A patient with type 1 diabetes always needs basal insulin, otherwise ketoacidosis develops; in long surgery or when the patient will miss more than one meal, an insulin infusion with glucose is used. A patient on prednisolone 5 mg or more a day for more than 4 weeks is at risk of adrenal insufficiency and receives cover, otherwise refractory hypotension may appear.
In phaeochromocytoma alpha blockade (phenoxybenzamine or doxazosin) is started 10–14 days before surgery, with salt and fluids, and only then is a beta-blocker added if there is tachycardia. During surgery handling the tumour causes sharp surges in pressure, and after the vein is ligated blood pressure falls and sometimes glucose too. Thyroid storm brings fever, tachycardia and atrial fibrillation; unlike malignant hyperthermia there is no muscle rigidity and no sharp rise in EtCO2. Treatment: a beta-blocker, an antithyroid drug, iodine only after it, hydrocortisone and cooling.
Key points
- Glucose 100–180 mg/dL; basal insulin is not stopped in type 1 diabetes.
- Steroid cover: hydrocortisone 100 mg at induction and 200 mg over 24 hours in major surgery.
- Phaeochromocytoma: alpha for 10–14 days, then beta.
- After tumour removal: hypotension and hypoglycaemia.
- Thyroid storm: beta-blocker, PTU or methimazole, iodine after them, hydrocortisone.
Summary table
| Condition | What is done | Exam point |
|---|---|---|
| Diabetes | Glucose 100–180 mg/dL; basal insulin slightly reduced; insulin infusion in long surgery | In type 1 diabetes basal insulin is never stopped |
| Long-term steroids | Usual dose; in major surgery hydrocortisone 100 mg at induction then 200 mg over 24 hours | Prednisolone 5 mg or more for more than 4 weeks |
| Phaeochromocytoma | Alpha blockade 10–14 days, then beta; in surgery — nitroprusside or phentolamine for surges | After vein ligation: hypotension and hypoglycaemia |
| Thyroid storm | Beta-blocker, PTU or methimazole, iodine after an hour, hydrocortisone, cooling | No rigidity and no sharp EtCO2 rise as in malignant hyperthermia |
| Carcinoid | Octreotide before surgery and in a crisis | Avoid histamine-releasing drugs |
A free exam question
בן 35 , המעומד לניתוח pituitary, סובל זמן רב מ- adenoma שמפרישה growth hormone (אבל לא ACTH ולא TSH .) ?איזה מהבאים הוא ביטוי קליני של המחלה שלו (the question as examined, in Hebrew)
- א. ( שבריריות העור skin fragility )
- ב. Hypotension
- ג. הפרעות בקצב הלב
- ד. רעד בידיים
In the full version for subscribers
- A simple algorithm
- Memory aid
- Exam traps
- 5 review cards
- Enough for IMLE
The full version is open to subscribers of: Anesthesiology, Internal medicine, General surgery, Medical licensing exam (IMLE).
Subscriber? Read the full topic Plans and prices 25 free questions
Sources
- ADA Standards of Care in Diabetes, 2024 — Diabetes care in the hospital: perioperative care
- Association of Anaesthetists guideline: Peri-operative use of corticosteroids in adults with or at risk of adrenal insufficiency, 2020 — Steroid cover
- Endocrine Society Clinical Practice Guideline: Pheochromocytoma and Paraganglioma, 2014 — Preoperative preparation
- Miller's Anesthesia, 9th edition (2020) — Anesthetic Implications of Concurrent Diseases: Endocrine Disease
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-02. The text may contain errors; when in doubt, check the source.