ADRENAL CRISIS
Adrenal crisis, or acute adrenal insufficiency, is a potentially life-threatening emergency which occurs as a result of cortisol deficiency. Prompt identification of affected patients and early initiation of therapy can be life-saving.
Clinical
presentation
A
history of pre-existing adrenal insufficiency or recent discontinuation of steroids may be apparent but some
patients present de
novo, and a high index of suspicion for the diagnosis is needed. Underlying conditions include primary
adrenal insufficiency
(Chapter 20), secondary adrenal insufficiency (Chapter 20) and chronic exogenous glucocorticoid
treatment (doses ≥5 mg prednisolone
equivalent for >4 weeks). This can
also
include patients treated chronically with nasal, topical or inhaled glucocorticoids.
Symptoms
and signs include fatigue, dizziness and
hypotension
(especially postural hypotension), collapse (including hypovolaemic shock), abdominal pain,
nausea, weight loss, fever,
confusion, delirium or even coma (Figure 35.1). Patients with primary adrenal insufficiency may be
pigmented (Chapter 20),
whereas patients with secondary adrenal
insufficiency
may be pale with symptoms of other pituitary hormone deficiency.
Biochemical
findings include hyponatraemia, hyperkalaemia, anaemia, pre-renal failure and hypoglycaemia
(predominantly in children).
Management
The
initial assessment should check blood pressure (including postural measurement) and fluid balance status (Figure
35.2). Blood tests
should include measurement of electrolytes, renal function, FBC, glucose, thyroid function
(thyrotoxicosis can trigger a
crisis), and paired serum cortisol and plasma ACTH. Definitive confirmation of
adrenal insufficiency usually requires a Synacthen test (Chapter 20) but unless
the patient is haemodynamically stable, treatment should not be delayed to
accommodate this.
Therapy
should commence as soon as the diagnosis is suspected. Patients usually have
significant reduction in fluid volume, hence immediate treatment should focus
on rehydration with 1 L 0.9% saline IV in the first 1–2 hours, followed by
further fluids as required (often 4–6 L in the first 24 hours). Care is needed
in the elderly and in those with cardiac or renal failure. If present,
hypoglycaemia should be treated with IV glucose.
Hydrocortisone
should be given as an immediate IV (or IM) bolus of 100 mg, followed by either
an infusion of 200 mg over 24 hours, or 50 mg IV/IM injection every 6 hours.
Tapering of hydrocortisone can occur after clinical improvement. Because
hydrocortisone has substantial mineralocorticoid activity in high doses,
fludrocortisone is not needed until total doses of hydrocortisone are <50
mg/day, and only then in patients with primary adrenal insufficiency (Chapter
20).
A
search for precipitants should include a screen for infection (treated as
necessary with antibiotics), a review of the history for any recent abrupt discontinuation
of chronic glucocorticoid therapy, and review of sick day rules (Chapter 20).
An
endocrinologist should be contacted as soon as the diagnosis is suspected.
Subsequent tests should look to establish the cause of the adrenal
insufficiency as in the non-acute state (Chapter 20).
Before
discharge from hospital, a check should be made to ensure that patients are
educated about the need to increase their glucocorticoid doses at times of
intercurrent illness, they are provided with a hydrocortisone emergency
injection kit, they carry a st couraged to wear medical alert jewellery.
