Читать книгу Clinical Pancreatology for Practising Gastroenterologists and Surgeons - Группа авторов - Страница 122

Serum calcium comprises ionized (free) calcium and nonionized calcium bound to albumin. Hypocalcemia with normal free calcium due to a decrease in plasma albumin is frequent in moderate‐to‐severe disease, given the catabolic distress of such a disease and the binding of calcium to necrotic adipose tissue [44]. This “false” hypocalcemia should not be treated but it is a classic marker of severe disease [45]. In the case of hypocalcemia, therefore, calcium should be corrected by albumin or proteins or ionized calcium should be measured. In the case of low free calcium levels, plasma magnesium should be measured to rule out hypomagnesemia as the cause of hypocalcemia. Hypocalcemia has been defined as an ionized calcium below 1.12 mmol/l and severe hypocalcemia as an ionized calcium below 0.8 mmol/l (3 mg/dl) [46]. Hypocalcemia may result in neuromuscular irritability, spasms, paresthesia, numbness, hyperreflexia, seizures, hallucinations, bradycardia, and hypotension [46]. The classic Trousseau (carpopedal spasm) and Chvostek (facial muscle hyperreflexia) signs and QT prolongation are typical of hypocalcemia. Patients with symptoms, a prolonged QT interval, or severe hypocalcemia should be treated.