Hypernatremia

Overview-Complications

Central nervous system thrombosis or hemorrhage Seizures Coma Permanent neurologic damage

Assessment-History

Fatigue Restlessness, agitation Weakness Disorientation Lethargy

Nursing Considerations-Associated Nursing Procedures

12- or 24-hour timed urine collection 12-lead electrocardiogram (ECG) Blood pressure assessment Cardiac monitoring IV bag preparation IV bolus injection IV catheter insertion IV pump use Intake and output assessment Neurologic assessment Nutritional screening Oral care Oral drug administration Postural vital signs measurement Pulse assessment Respiration assessment Seizure management Urine specimen collection, random Venipuncture

Treatment-Medications

Administration of salt-free solutions (such as dextrose in water), followed by infusion of half-normal saline solution to prevent hyponatremia Additionally, I.V. fluids for hydration Isotonic saline or lactated Ringer's solution for hypovolemia Hypotonic fluids for excess sodium Isotonic saline or lactated Ringer's solution for hypovolemia Hypotonic fluids for excess sodium Desmopressin (DDAVP) intranasally for neurogenic diabetes insipidus Chlorothiazide or chlorpropamide for nephrogenic diabetes insipidus

Overview-Causes

Antidiuretic hormone deficiency (diabetes insipidus) Certain drugs (see Drugs causing hypernatremia) Decreased water intake Excess adrenocortical hormones, as in Cushing's syndrome Excessive I.V. administration of sodium solutions Salt intoxication (less common), which may be produced by excessive table salt ingestion Sea water ingestion GI fluid loss, such as with diarrhea Extreme sports with profuse sweating

Nursing Considerations-Nursing Diagnoses

Anxiety Deficient fluid volume Fear Risk for decreased cardiac perfusion Risk for ineffective renal perfusion Risk for injury

Treatment-Activity

Bed rest initially Activity as tolerated once the patient's condition is stable or the underlying condition is controlled or resolved

Nursing Considerations-Nursing Interventions

Obtain a drug history to check for drugs that promote sodium retention. Give water replacement orally if the patient is alert and responsive. Administer I.V. fluid replacement based on the underlying cause to assist in normalizing serum sodium levels; ensure patent I.V. access. Obtain blood specimens frequently to evaluate serum electrolyte levels, as frequently as every 1 to 2 hours if necessary. Obtain urine specimens to evaluate urine osmolality. Assist with oral hygiene measures. Observe for signs of cerebral edema during fluid replacement therapy. Assist with measures to address underlying conditions (such as diabetes).

Treatment-Diet

Oral water if the patient is alert and responsive Sodium restriction

Patient Teaching-Discharge Planning

Refer the patient and family to social services for assistance if access to water is a problem.

Diagnostic Test Results-Laboratory

Serum sodium level is greater than 145 mEq/L. Urine sodium level is less than 40 mEq/24 hours, with high serum osmolality.

Nursing Considerations-Monitoring

Serum sodium levels Urine osmolality Cardiopulmonary status Renal function Intake and output Daily weight Hydration status Neurologic status

Overview-Pathophysiology

Sodium is the major cation (90%) in extracellular fluid, and potassium is the major cation in intracellular fluid. During repolarization, the sodium-potassium pump continually shifts sodium into the cells and potassium out of the cells; during depolarization, it does the reverse. Sodium cation functions include maintaining tonicity and concentration of extracellular fluid, acid-base balance (reabsorption of sodium ion and excretion of hydrogen ion), nerve conduction and neuromuscular function, glandular secretion, and water balance. A net water loss or hypertonic sodium gain occurs, which reflects less water in relation to total body sodium and potassium. Increased sodium causes high serum osmolality (increased solute concentrations in the body), which stimulates the hypothalamus and initiates the sensation of thirst.

Overview-Incidence

Hypernatremia occurs in about 0.3% to 5.5% of hospitalized patients. Elderly patients are at high risk.

Overview

Hyperosmolar condition involving a relative deficit of water in relation to solute; considered a water problem Resultant excessive serum levels of the sodium cation relative to body water

Treatment-General

Treatment of underlying cause Discontinuation of drugs that promote sodium retention Dialysis for serum sodium levels greater than 200 mEq/L

Patient Teaching-General

disorder, possible underlying causes, and treatment importance of sodium restriction and ways to increase water intake low-sodium diet, if indicated, including foods to avoid prescribed drugs, if appropriate signs and symptoms of hypernatremia and hyponatremia, including the need to notify a practitioner if any occur importance of avoiding over-the-counter medications that contain sodium and checking with a practitioner before using any over-the-counter medications need for access to water importance of continued follow-up, including laboratory testing as necessary to evaluate the condition.

Nursing Considerations-Expected Outcomes

identify strategies to reduce anxiety maintain adequate fluid volume discuss fears and concerns exhibit signs of adequate cardiopulmonary perfusion demonstrate adequate renal function avoid complications.

Assessment-Physical Findings

Flushed skin (see Clinical effects of hypernatremia) Dry, swollen tongue Sticky mucous membranes Low-grade fever Twitching Hypertension, dyspnea (with hypervolemia) Orthostatic hypotension and oliguria or anuria (with hypovolemia) Sunken eyes

Overview-Risk Factors

Inability to drink voluntarily Age over 65 years Lack of access to water Diuretic use