Endocrine emergencies are protocol-sensitive but physiology-dependent. This masterclass separates insulin strategies for DKA/HHS/hyperkalemia, stress-dose corticosteroids for adrenal crisis, desmopressin for central DI, and the sequencing principles of thyroid emergencies.
Use different insulin endpoints and rates for DKA, pure HHS and hyperkalemia.
Never start DKA insulin into significant hypokalemia without first correcting potassium.
Treat suspected adrenal crisis immediately with parenteral hydrocortisone and fluids rather than waiting for confirmatory testing.
Use desmopressin only after the polyuria/osmolality phenotype supports central DI or a deliberate sodium-overcorrection strategy.
Understand thyroid-storm and myxedema-coma drug sequencing even when those agents are managed under institution-specific endocrine protocols.
The table below is a selection framework. Open the individual monograph for exact dosing, preparation, renal/CRRT/IHD adjustment, interactions and evidence traceability.
ICU role: Primary IV hormone therapy for DKA/HHS and a separate temporizing therapy for hyperkalemia.
Monitor: Glucose, K, ketones/pH/bicarbonate or osmolality depending on indication.
ICU role: Preferred glucocorticoid for adrenal crisis and selected septic-shock/stress indications.
Monitor: Hemodynamics, glucose, electrolytes, clinical response.
ICU role: Long-acting glucocorticoid used in selected neuro/oncologic/inflammatory settings and sometimes when cortisol testing must remain interpretable.
Monitor: Glucose, infection, neuropsychiatric and muscle effects.
ICU role: V2 agonist used for central diabetes insipidus and selected sodium-overcorrection control.
Monitor: Na, urine output/osmolality, fluid intake/output.
| Agent | ICU role | Why I choose it | Why I hesitate | What I monitor |
|---|---|---|---|---|
| Regular Insulin (IV) Rapid-Onset IV Insulin — Endogenous Peptide Hormone | Primary IV hormone therapy for DKA/HHS and a separate temporizing therapy for hyperkalemia. | ✓ Use indication-specific dosing and endpoints; DKA therapy continues until ketoacidosis resolves, not simply until glucose normalizes. | ✕ Hypoglycemia/hypokalemia; renal failure prolongs effect. | Glucose, K, ketones/pH/bicarbonate or osmolality depending on indication. |
| Hydrocortisone Short-Acting Glucocorticoid with Clinically Relevant Mineralocorticoid Activity | Preferred glucocorticoid for adrenal crisis and selected septic-shock/stress indications. | ✓ Immediate stress-dose therapy in suspected adrenal crisis because delay can be fatal. | ✕ Hyperglycemia, infection risk, neuromuscular/psychiatric effects; indication and duration matter. | Hemodynamics, glucose, electrolytes, clinical response. |
| Dexamethasone Long-Acting Synthetic Fluorinated Glucocorticoid (High Anti-Inflammatory Potency) with Negligible Mineralocorticoid Activity | Long-acting glucocorticoid used in selected neuro/oncologic/inflammatory settings and sometimes when cortisol testing must remain interpretable. | ✓ Useful where mineralocorticoid effect is undesirable or a disease-specific dexamethasone regimen exists. | ✕ Not the preferred routine replacement steroid for adrenal crisis when hydrocortisone is available. | Glucose, infection, neuropsychiatric and muscle effects. |
| Desmopressin Synthetic Vasopressin V2 Receptor Agonist / Hemostatic Peptide | V2 agonist used for central diabetes insipidus and selected sodium-overcorrection control. | ✓ Central DI with hypernatremic dilute polyuria after appropriate diagnostic assessment. | ✕ Water intoxication/hyponatremia if fluids are not coordinated; nephrogenic DI will not respond reliably. | Na, urine output/osmolality, fluid intake/output. |
Why: Insulin drives potassium intracellularly and can precipitate lethal arrhythmia/respiratory weakness in significant hypokalemia.
Why: The core DKA target is suppression of ketogenesis, not just glucose lowering.
Why: Rapid osmotic shifts and potassium decline are major hazards.
Why: Guidelines prioritize immediate therapy in severe suspected adrenal insufficiency/adrenal crisis.
Why: Osmotic diuresis, post-obstructive diuresis and fluid mobilization can mimic DI.
Recognition becomes selection, then organ-failure adjustment, competing physiology and senior-level prioritization.
DKA, glucose 31 mmol/L, pH 7.08, K 3.2 mmol/L.
Replace potassium first and delay insulin until K is >3.5 mmol/L, while continuing appropriate fluid resuscitation and monitoring.
After treatment glucose is 10 mmol/L but beta-hydroxybutyrate remains elevated and bicarbonate is 14 mmol/L.
Add/continue dextrose and keep IV insulin running until DKA resolution criteria are met. Stopping because glucose normalized risks rebound ketosis.
Chronic steroid user presents with vomiting, Na 124, K 5.8 and vasopressor-requiring shock.
Treat suspected adrenal crisis immediately with parenteral hydrocortisone and fluids; obtain diagnostic bloods first only if they do not delay treatment. Reassess other shock causes in parallel.
Severe thyrotoxicosis, AF 150/min, pulmonary edema, lactate elevation and echo showing EF 15% with cold extremities.
This is not a simple 'give propranolol' case. Treat thyroid storm multimodally, but beta blockade must be cautious/short-acting or deferred if low-output shock is present; support hemodynamics and treat the precipitant while thionamide → iodine sequencing and corticosteroid proceed.
Na rises from 142 to 158 mmol/L over 10 h, urine output 700 mL/h, urine osmolality 90 mOsm/kg after pituitary surgery; patient is also receiving hypertonic saline for ICP.
Recognize central DI superimposed on a neuro-osmotherapy plan. Stop/reassess unnecessary sodium load, replace free water deliberately, give DDAVP with close urine/Na monitoring, and coordinate the ICP target so DI treatment does not conflict with neurocritical goals.
IV regular insulin is used for distinct ICU purposes — DKA, HHS/mixed hyperglycemic crisis, temporizing potassium shift in hyperkalemia, and general ICU glycemic control — each with different dosing and endpoints; insulin SHIFTS …
Short-acting glucocorticoid with mineralocorticoid activity used in acute adrenal crisis and commonly used when corticosteroids are chosen for adult septic shock; current guidelines support corticosteroids in septic shock but do …
Potent long-acting glucocorticoid with negligible mineralocorticoid activity. It is used for selected indications including adjunctive acute bacterial meningitis when given before/with initial antibiotics, symptomatic vasogenic t…
Synthetic vasopressin analog with strong V2 antidiuretic activity and endothelial release of von Willebrand factor/factor VIII. It is labeled for central diabetes insipidus and selected bleeding disorders; ICU use for uremic blee…
This Masterclass teaches selection and reasoning. Exact dosing, concentration, infusion preparation, renal/hepatic/RRT adjustment and monitoring must be checked in the linked medication monograph and the institution's current formulary/protocol. Local resistance patterns and regulatory drug availability can change faster than a static teaching page.