Only recently have endocrine disorders in critically ill patients been
given detailed consideration.
Diabetic ketoacidosis (DKA) and hyperglycaemic hyperosmolar
state (HHS) are the major hyperglycaemic crises associated with diabetes
mellitus. They are frequently considered as separate conditions but as will
be shown in the following discussions they really represent two ends of a
spectrum of hyperglycaemic and metabolic derangement, and not
infrequently exist in combination. As many as 30–33% of all
hyperglycaemic crisis admissions can be expected to have a mixed
DKA/HHS metabolic picture.
Diabetic ketoacidosis (DKA) is an acute, major, life-threatening
complication of diabetes. DKA mainly occurs in patients with type 1
diabetes, but it is not uncommon in some patients with type 2 diabetes.
DKA is defined clinically as an acute state of severe uncontrolled
diabetes that requires emergency treatment with insulin and intravenous
fluids. Biochemically, DKA is defined as an increase in the serum
concentration of ketones greater than 5 mEq/L, a blood glucose level of
greater than 300 mg/dL (although it is usually much higher) and
metabolic acidosis.
Thyroid storm is a clinical manifestation of an extreme hyperthyroid
state that results in significant morbidity or disability or even death.
Previously, thyroid storm was a common complication of toxic goiter
surgery during intraoperative and postoperative stages. Preoperative
control of the thyrotoxic state and use of radioiodine ablation has greatly
reduced this phenomenon. Today, thyroid storm more commonly is seen
Summary
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in a thyrotoxic patient with intercurrent illness or surgical emergency.
Early recognition and prompt intervention are necessary to prevail in
management of this phenomenon.
myxedema coma, an uncommon but life-threatening form of
untreated hypothyroidism with physiological decompensation.The
condition occurs in patients with long-standing, untreated hypothyroidism
and is usually precipitated by a secondary insult, such as climate-induced
hypothermia, infection, or another systemic condition, or drug therapy.
Patients with myxedema coma have changes in their mental status,
including lethargy, stupor, delirium, or coma. A more appropriate term
for myxedema coma is myxedema crisis; we often use the term
myxedema coma/crisis.
Adrenal crisis and severe acute adrnocortical insufficiency are often
elusive diagnoses that may result in severe morbidity and mortality when
undiagnosed or ineffectively treated.
In primary adrenocortical insufficiency, glucocorticoid and
mineralocorticoid properties are lost; however, in secondary
adrenocortical insufficiency (ie, secondary to disease or suppression of
the hypothalamic-pituitary axis), mineralocorticoid function is preserved.
Every emergency physician should be familiar with adrenocortical
insufficiency, which is a potentially life-threatening entity. The initial
diagnosis and decision to treat are presumptive and are based on history,
physical examination, and, occasionally, laboratory findings. Delay in
treatment while attempting to confirm this diagnosis can result in poor
patient outcomes.
Summary
106
Pheochromocytoma is a rare catecholamine-secreting tumorderived
from chromaffin cells. When such tumors arise outside of the adrenal
gland, they are termed extra-adrenal pheochromocytomas, or
paragangliomas. Because of excessive catecholamine secretion,
pheochromocytomas may precipitate life-threatening hypertension or
cardiac arrhythmias. If the diagnosis of a pheochromocytoma is
overlooked, the consequences could be disastrous, even fatal; however, if
a pheochromocytoma is found, it is potentially curable. |
