M15Endocrine crises, overdose and poisoning

Clinical overview

Endocrine and toxicological emergencies are mechanism-driven resuscitations. Maternal stabilisation takes priority because hypoxia, shock, seizure, hyperthermia and severe acid–base disturbance are more immediately dangerous to the fetus than most antidotes. Pregnancy alters distribution and clearance and adds fetal monitoring, but it rarely justifies withholding a life-saving antidote or dialysis.

The first steps are ABCDE, glucose, temperature, ECG, acid–base/electrolytes and identification of toxidrome or endocrine pattern. Call a poison information centre/clinical toxicologist early for significant exposure and use the current local antidote protocol. Drug concentrations and toxicity thresholds must be interpreted against timing, formulation, co-ingestants and treatment already given.

Core knowledge

Adrenal crisis

Consider adrenal crisis with refractory hypotension, vomiting/abdominal pain, weakness, hyponatraemia, hyperkalaemia or hypoglycaemia, especially with known adrenal disease, chronic steroid exposure, pituitary disease, TB, sepsis or abrupt steroid withdrawal. Pregnancy symptoms can obscure it.

Treat immediately with IV hydrocortisone under the emergency protocol, isotonic fluid matched to haemodynamics, glucose when low and correction of electrolyte/precipitating disease. Do not wait for cortisol results; draw cortisol/ACTH first only if this does not delay steroids. In septic shock with persistent vasopressor need, corticosteroid use follows current sepsis guidance even without proven primary adrenal failure.

Thyroid storm

Thyroid storm is severe thyrotoxicosis with thermoregulatory, cardiovascular and CNS dysfunction, often precipitated by infection, surgery, labour, medication interruption or iodine exposure. Features include fever, agitation/delirium, marked tachycardia/arrhythmia, heart failure and GI/hepatic dysfunction. Scoring systems support but do not replace clinical diagnosis.

Treat in ICU with supportive cooling/fluids, beta-blockade selected for haemodynamics, antithyroid therapy, iodine given in the correct sequence after thionamide, corticosteroid and precipitant treatment under endocrine/obstetric guidance. Propylthiouracil and carbimazole/methimazole have trimester-specific risk considerations, but storm demands effective treatment. Avoid aspirin for fever because it can increase free thyroid hormone; use safer antipyresis and external cooling.

Myxoedema coma

Myxoedema coma presents with altered consciousness, hypothermia, hypoventilation, bradycardia, hyponatraemia and cardiovascular failure. Treat with airway/ventilatory support, IV thyroid hormone and stress-dose hydrocortisone until adrenal insufficiency is excluded, plus careful warming and correction of precipitant/electrolytes. Aggressive peripheral rewarming can worsen vasodilatation; use controlled supportive warming.

Tap to enlarge

Figure M15.1 — Endocrine crisis patterning separates cortisol failure, excess thyroid drive and severe thyroid-hormone deficiency, linking each syndrome to immediate maternal rescue without waiting for endocrine results.

Toxicology operating principles

1. Stabilise airway, ventilation and circulation; check glucose and temperature.
2. Obtain ECG with QRS/QT assessment, gas, electrolytes, renal/liver function, paracetamol level and exposure-specific tests.
3. Identify toxidrome: opioid, sympathomimetic, anticholinergic, cholinergic, sedative, serotonin or sodium-channel blockade.
4. Prevent further absorption only when benefit exceeds aspiration/procedural risk.
5. Give a specific antidote when indicated; do not delay supportive care.
6. Enhance elimination for selected toxins through urinary manipulation or dialysis.
7. Monitor mother continuously; assess fetus after maternal stabilisation.
8. Address intentional self-harm, safeguarding and psychiatric care once medically safe.