Electrolyte and Protein Disorders

Disorders of Sodium

Hypernatremia

• Definition: Plasma Na+ >145 mEq/L, caused by a deficit of H2O relative to solute
• Mortality: 40-60%
• Pathogenesis: Usually caused by excess loss of H2O from body that is not adequately replaced
• Risk Factors: Vomiting, Diarrhea, Renal disease, Taking loop diuretics, Burns, Excessive sweating
• Pathogenesis (continued): Osmotic diuresis, Renal insufficiency, Diabetes insipidus, Inability to access H2O
• Symptoms: Thirst, CNS Symptoms (Brain stem shrinkage, Confusion, Neuromuscular irritability, Seizures, Coma)
• Treatment: H2O replacement is primary goal, IV with D5W if patient cannot drink

Principle Causes of Hypernatremia

• Hypernatremia with Hypovolemia (Extrarenal losses, Renal losses, Intrinsic renal disease, Osmotic diuresis)
• Hypernatremia with Euvolemia (Inability to access H2O, Primary hypodipsia, Reset osmostat)
• Hypernatremia with Hypervolemia (Hyper-tonic IV fluids, Hypertonic Saline, NaHCO3, TPN)

Disorders of Sodium (continued)

Hyponatremia

• Definition: Plasma Na+ <135 mEq/L, caused by Na+ loss than H2O
• Pathogenesis: Significant ECF loss results in release of ADH, causing H2O retention by kidneys and hyponatremia
• Euvolemic Hyponatremia: Dilutional hyponatremia, Renal failure, Addison's disease, Myxedema, or nonosmotic ADH secretion
• Hypervolemic Hyponatremia: Increase in TBW and total body Na+ content, CHF and Liver Failure
• Symptoms: Effects on CNS, Brain cellular H2O increases in acute and chronic hyponatremia

Principle Causes of Hyponatremia

• Hyponatremia with Hypovolemia (GI, Syndrome of Inappropriate ADH secretion, Congestive Heart Failure, 3rd spacing)
• Hyponatremia with Euvolemia (Diuretics, Osmotic diuresis, Mineralocorticoid deficiency, Salt-losing nephropathies)
• Hyponatremia with Hypervolemia (Congestive Heart Failure, Liver Failure, Renal disease)

Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH)

• Definition: Less than maximally dilute urine in presence of plasma hypoosmolality and hyponatremia
• Pathogenesis: Sustained ADH release, Osmotic threshold for ADH release is subnormally low, In some, ADH is not suppressed in presence of low plasma osmolality
• Diagnosing SIADH: Symptoms of hyponatremia, Low PO4- indicates some form of hyperparathyroidism

Disorders of Calcium

• Hypercalcemia: Parathyroid Hormone Assays, PTH by IRMA, Diagnosis is usually made by presence of PTH-related peptide
• Diagnostic Tests: PTH Assays, Check urinary excretion of calcium
• Treatment: If symptoms are mild and Ca+ <15 mg/dL, conservative approach is appropriate, Prominent symptoms include anxiety, nervousness, daytime sleepiness, loss of energy, crying easily, excessive worry, irritability, lack of interest
• Therapy: Rate of complications is low in the asymptomatic patient, Decision for or against surgery is based on complicating problems, Mild hypercalcemia in postmenopausal women may respond to estrogens, For Vitamin D excess, Prednisone usually controls the Ca+
• Treatment (continued): With normal renal function, IV of 0.9% NS with KCL and Lasix, In patients with malignancy, bisphosphonates plus NS and Lasix, If hyperparathyroidism is symptomatic and progressive, surgery is treatment of choice

Disorders of Sodium

Hypernatremia

• Definition: Plasma Na+ >145 mEq/L, caused by a deficit of H2O relative to solute
• Mortality: 40-60%
• Pathogenesis: Usually caused by excess loss of H2O from body that is not adequately replaced
• Risk Factors: Vomiting, Diarrhea, Renal disease, Taking loop diuretics, Burns, Excessive sweating
• Pathogenesis (continued): Osmotic diuresis, Renal insufficiency, Diabetes insipidus, Inability to access H2O
• Symptoms: Thirst, CNS Symptoms (Brain stem shrinkage, Confusion, Neuromuscular irritability, Seizures, Coma)
• Treatment: H2O replacement is primary goal, IV with D5W if patient cannot drink

Principle Causes of Hypernatremia

• Hypernatremia with Hypovolemia (Extrarenal losses, Renal losses, Intrinsic renal disease, Osmotic diuresis)
• Hypernatremia with Euvolemia (Inability to access H2O, Primary hypodipsia, Reset osmostat)
• Hypernatremia with Hypervolemia (Hyper-tonic IV fluids, Hypertonic Saline, NaHCO3, TPN)

Disorders of Sodium (continued)

Hyponatremia

• Definition: Plasma Na+ <135 mEq/L, caused by Na+ loss than H2O
• Pathogenesis: Significant ECF loss results in release of ADH, causing H2O retention by kidneys and hyponatremia
• Euvolemic Hyponatremia: Dilutional hyponatremia, Renal failure, Addison's disease, Myxedema, or nonosmotic ADH secretion
• Hypervolemic Hyponatremia: Increase in TBW and total body Na+ content, CHF and Liver Failure
• Symptoms: Effects on CNS, Brain cellular H2O increases in acute and chronic hyponatremia

Principle Causes of Hyponatremia

• Hyponatremia with Hypovolemia (GI, Syndrome of Inappropriate ADH secretion, Congestive Heart Failure, 3rd spacing)
• Hyponatremia with Euvolemia (Diuretics, Osmotic diuresis, Mineralocorticoid deficiency, Salt-losing nephropathies)
• Hyponatremia with Hypervolemia (Congestive Heart Failure, Liver Failure, Renal disease)

Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH)

• Definition: Less than maximally dilute urine in presence of plasma hypoosmolality and hyponatremia
• Pathogenesis: Sustained ADH release, Osmotic threshold for ADH release is subnormally low, In some, ADH is not suppressed in presence of low plasma osmolality
• Diagnosing SIADH: Symptoms of hyponatremia, Low PO4- indicates some form of hyperparathyroidism

Disorders of Calcium

• Hypercalcemia: Parathyroid Hormone Assays, PTH by IRMA, Diagnosis is usually made by presence of PTH-related peptide
• Diagnostic Tests: PTH Assays, Check urinary excretion of calcium
• Treatment: If symptoms are mild and Ca+ <15 mg/dL, conservative approach is appropriate, Prominent symptoms include anxiety, nervousness, daytime sleepiness, loss of energy, crying easily, excessive worry, irritability, lack of interest
• Therapy: Rate of complications is low in the asymptomatic patient, Decision for or against surgery is based on complicating problems, Mild hypercalcemia in postmenopausal women may respond to estrogens, For Vitamin D excess, Prednisone usually controls the Ca+
• Treatment (continued): With normal renal function, IV of 0.9% NS with KCL and Lasix, In patients with malignancy, bisphosphonates plus NS and Lasix, If hyperparathyroidism is symptomatic and progressive, surgery is treatment of choice

Disorders of Sodium

Hypernatremia

• Definition: Plasma Na+ >145 mEq/L, caused by a deficit of H2O relative to solute
• Mortality: 40-60%
• Pathogenesis: Usually caused by excess loss of H2O from body that is not adequately replaced
• Risk Factors: Vomiting, Diarrhea, Renal disease, Taking loop diuretics, Burns, Excessive sweating
• Pathogenesis (continued): Osmotic diuresis, Renal insufficiency, Diabetes insipidus, Inability to access H2O
• Symptoms: Thirst, CNS Symptoms (Brain stem shrinkage, Confusion, Neuromuscular irritability, Seizures, Coma)
• Treatment: H2O replacement is primary goal, IV with D5W if patient cannot drink

Principle Causes of Hypernatremia

• Hypernatremia with Hypovolemia (Extrarenal losses, Renal losses, Intrinsic renal disease, Osmotic diuresis)
• Hypernatremia with Euvolemia (Inability to access H2O, Primary hypodipsia, Reset osmostat)
• Hypernatremia with Hypervolemia (Hyper-tonic IV fluids, Hypertonic Saline, NaHCO3, TPN)

Disorders of Sodium (continued)

Hyponatremia

• Definition: Plasma Na+ <135 mEq/L, caused by Na+ loss than H2O
• Pathogenesis: Significant ECF loss results in release of ADH, causing H2O retention by kidneys and hyponatremia
• Euvolemic Hyponatremia: Dilutional hyponatremia, Renal failure, Addison's disease, Myxedema, or nonosmotic ADH secretion
• Hypervolemic Hyponatremia: Increase in TBW and total body Na+ content, CHF and Liver Failure
• Symptoms: Effects on CNS, Brain cellular H2O increases in acute and chronic hyponatremia

Principle Causes of Hyponatremia

• Hyponatremia with Hypovolemia (GI, Syndrome of Inappropriate ADH secretion, Congestive Heart Failure, 3rd spacing)
• Hyponatremia with Euvolemia (Diuretics, Osmotic diuresis, Mineralocorticoid deficiency, Salt-losing nephropathies)
• Hyponatremia with Hypervolemia (Congestive Heart Failure, Liver Failure, Renal disease)

Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH)

• Definition: Less than maximally dilute urine in presence of plasma hypoosmolality and hyponatremia
• Pathogenesis: Sustained ADH release, Osmotic threshold for ADH release is subnormally low, In some, ADH is not suppressed in presence of low plasma osmolality
• Diagnosing SIADH: Symptoms of hyponatremia, Low PO4- indicates some form of hyperparathyroidism

Disorders of Calcium

• Hypercalcemia: Parathyroid Hormone Assays, PTH by IRMA, Diagnosis is usually made by presence of PTH-related peptide
• Diagnostic Tests: PTH Assays, Check urinary excretion of calcium
• Treatment: If symptoms are mild and Ca+ <15 mg/dL, conservative approach is appropriate, Prominent symptoms include anxiety, nervousness, daytime sleepiness, loss of energy, crying easily, excessive worry, irritability, lack of interest
• Therapy: Rate of complications is low in the asymptomatic patient, Decision for or against surgery is based on complicating problems, Mild hypercalcemia in postmenopausal women may respond to estrogens, For Vitamin D excess, Prednisone usually controls the Ca+
• Treatment (continued): With normal renal function, IV of 0.9% NS with KCL and Lasix, In patients with malignancy, bisphosphonates plus NS and Lasix, If hyperparathyroidism is symptomatic and progressive, surgery is treatment of choice