9.5 Endocrine and Metabolic Alterations

Endocrine and Metabolic Alterations

Endocrine items test contrasts: type 1 vs. type 2 diabetes, DKA vs. HHS, hyper- vs. hypothyroid, SIADH vs. DI, Addison's vs. Cushing's. Pair each pattern with its emergency and the priority action.

Diabetes Mellitus

Long-term complications: retinopathy, nephropathy (proteinuria), neuropathy with foot ulcers, accelerated cardiovascular disease, and poor wound healing/infection. Insulin onset/peak matters for hypoglycemia timing: rapid-acting lispro/aspart peaks ~1 hour (give with food); regular peaks 2–3 hours; NPH peaks 4–12 hours; long-acting glargine is peakless and is never mixed in the same syringe. When mixing regular and NPH, draw up clear (regular) before cloudy (NPH) — "clear before cloudy."

Diabetic Emergencies

Rule of 15 for hypoglycemia (conscious, can swallow): give 15 g fast-acting carbohydrate (4 oz juice, glucose tabs), wait 15 minutes, recheck; repeat if still <70 mg/dL, then a protein/complex-carb snack. If unconscious or unable to swallow: glucagon IM or IV dextrose 50% with IV access — never force oral intake. DKA and HHS both need IV fluids, IV insulin, and electrolyte (especially potassium) correction; watch potassium closely as insulin drives it into cells.

Thyroid Disorders

Thyroid storm: uncontrolled hyperthyroidism → fever >104°F, extreme tachycardia, hypertension, agitation; treat with beta blockers, antithyroid drugs, and cooling. Myxedema coma: severe hypothyroidism → hypothermia, bradycardia, hypotension, decreasing LOC; treat with IV thyroid hormone and slow rewarming. After thyroidectomy, keep calcium gluconate at the bedside (parathyroid injury → hypocalcemic tetany).

Adrenal Disorders

Addison's disease (cortisol + aldosterone deficiency): hypotension, hyperpigmentation, weakness, weight loss, hyperkalemia, hyponatremia, hypoglycemia. Addisonian crisis — triggered by stress/illness — causes profound hypotension and shock; treat with IV hydrocortisone, fluids, and vasopressors. Cushing's syndrome (cortisol excess): moon face, buffalo hump, truncal obesity, hypertension, hyperglycemia, thin bruisable skin, muscle wasting, osteoporosis, and immunosuppression. Memory hook: Addison's Adds down (deficiency, low BP/Na/glucose), Cushing's Cranks up (excess, high BP/glucose).

Posterior Pituitary: DI vs. SIADH

Memory aids: DI = Dilute and Insatiable (lots of dilute urine), and SIADH = Sodium Is Always Dropping Here (retained water dilutes sodium).

Parathyroid

• Hyperparathyroidism (↑PTH → ↑calcium): "bones, stones, abdominal moans, psychiatric groans" — fractures, kidney stones, constipation, weakness.
• Hypoparathyroidism (↓PTH → ↓calcium): tetany, positive Chvostek's and Trousseau's signs, seizures, paresthesias, cardiac arrhythmias.

Insulin Administration: Tested Details

Insulin is one of the most error-prone medications, so the exam drills its specifics. Always confirm the dose with a second licensed nurse per policy, and use only an insulin syringe marked in units — never a tuberculin syringe. Rotate sites within one anatomic region (the abdomen absorbs fastest and most predictably) to prevent lipohypertrophy. Store the in-use vial at room temperature and refrigerate spares; never freeze insulin.

When sliding-scale coverage is ordered, give rapid- or short-acting insulin with or just before a meal and confirm the tray has arrived, so the patient does not peak without food and crash into hypoglycemia.

Sick-Day Rules and Patient Teaching

Diabetes self-management teaching is squarely LPN/VN territory and a steady source of correct answers. Teach patients that illness raises blood glucose even when appetite drops, so they must never skip insulin when sick. They should monitor glucose more frequently, check urine ketones if type 1, maintain hydration with sugar-free fluids, and call the provider for persistent vomiting, glucose above 240 mg/dL with ketones, or inability to keep fluids down. Foot care is lifelong: inspect daily, wash and dry between toes, wear closed shoes, and never go barefoot — neuropathy hides injuries until they ulcerate.

Connecting Endocrine Emergencies to Their Labs

Every endocrine crisis has a signature lab, and pairing them speeds your answer selection. Hyponatremia points you toward SIADH or adrenal insufficiency; hypernatremia with massive dilute urine points to diabetes insipidus; hyperkalemia with hypoglycemia and hypotension points to Addisonian crisis; hyperglycemia with ketones and a low pH points to DKA; and profound hyperglycemia without ketones points to HHS.

Whenever insulin therapy is running for DKA or HHS, anticipate a falling potassium as insulin shifts it into cells — monitoring and replacing potassium is the high-yield nursing priority that the test expects you to flag.