2014-18 Treatment Hypernatremia Treat the underlying disease, if possible Hypernatremia, defined as a plasma sodium concentration greater than 144 mmol/L, ral or intravenous sodium chloride in patients with true always reflects a state of hypertonicity. Sodium chloride administration is also effective in patients the (SIADH)using either oral salt tablets or hypertonic saline. rast, isotonic saline is often not effective and may orsen the hyponatremia in SIADH Administration of a vasopressin receptor antagonist Causes of hypernatremia Diabetes insipidus(Dl) Hypovolemia: associated with low total body sodium of both Na+ and water, but with a relatively greater los Patients with central and nephrogenic DI and primary Hypervolemia: associated with increased total body sodium mia: hypertonic saline solutions have emerged eferable alternative to mannitol for treatment of inert complished by clinical evaluation, with measurements of vasopressin level and Euvolemia: associated with normal body sodium response to a water deprivation test followed by vasopressin Most patients with hypernatremia secondary to water loss appear dy Na+ because loss of water without Na+ does not lead to Clinical Manifestations Central Diabetes Insipidus Congenital Nephrogenic Diabetes Insipidus red mental status, lethargy irritability restlessness, seizures(usually in children), muscle twitching, hyperreflexia Fever, nausea or vomiting, labored breathing, and intense mol/l are associated with a 75% mortality, although this may reflect associated comorbidities rather than hypernatremia per se 82014-1-8 8 Treatment • Treat the underlying disease, if possible. • Fluid restriction. • Oral or intravenous sodium chloride in patients with true volume depletion. • Sodium chloride administration is also effective in patients the syndrome of inappropriate antidiuretic hormone secretion (SIADH) using either oral salt tablets or hypertonic saline. • In contrast, isotonic saline is often not effective and may worsen the hyponatremia in SIADH • Administration of a vasopressin receptor antagonist Hypernatremia • Hypernatremia, defined as a plasma sodium concentration greater than 144 mmol/L, always reflects a state of hypertonicity. Causes of Hypernatremia • Hypovolemia: associated with low total body sodium – losses of both Na+ and water, but with a relatively greater loss of water • Hypervolemia: associated with increased total body sodium – administration of hypertonic solutions such as 3% NaCl, NaHCO3. – Therapeutic hypernatremia: hypertonic saline solutions have emerged as a preferable alternative to mannitol for treatment of increased intracranial pressure. • Euvolemia: associated with normal body sodium – Most patients with hypernatremia secondary to water loss appear euvolemic with normal total body Na+ because loss of water without Na+ does not lead to overt volume contraction Diabetes insipidus (DI) • Characterized by polyuria and polydipsia • Caused by defects in vasopressin action. • Patients with central and nephrogenic DI and primary polydipsia present with polyuria and polydipsia. • The differentiation between these entities can be accomplished by clinical evaluation, with measurements of – vasopressin levels and – the response to a water deprivation test followed by vasopressin administration • Central Diabetes Insipidus • Congenital Nephrogenic Diabetes Insipidus • Acquired Nephrogenic Diabetes Insipidus Clinical Manifestations • Signs and symptoms mostly relate to the CNS and include altered mental status, lethargy, irritability, restlessness, seizures (usually in children), muscle twitching, hyperreflexia, and spasticity. • Fever, nausea or vomiting, labored breathing, and intense thirst can also occur. • In adults, serum Na+ concentrations above 160 mmol/l are associated with a 75% mortality, although this may reflect associated comorbidities rather than hypernatremia per se