Electrolyte imbalances sodium

Hyponatremia patient profile

A low sodium level in the blood may result from excess water or fluid in the body, diluting the normal amount of sodium so that the concentration appears low. This type of hyponatremia can be the result of chronic conditions such as kidney failure (when excess fluid cannot be efficiently excreted) and congestive heart failure, in which excess fluid accumulates in the body. SIADH (syndrome of inappropriate anti-diuretic hormone) is a disease whereby the body produces too much anti-diuretic hormone (ADH), resulting in retention of water in the body. Consuming excess water, for example during strenuous exercise, without adequate replacement of sodium, can also result in hyponatremia. Hyponatremia can also result when sodium is lost from the body or when both sodium and fluid are lost from the body, for example, during prolonged sweating and severe vomiting or diarrhea.

Actual and relative sodium deficits

Actual sodium deficits: excessive diaphoresis, diuretics, wound drainage, kidney disease, decrease secretion of aldosterone, low salt diets, NPO, vomiting, diarrhea, gastric suctioning Relative sodium deficits (dilution): excessive ingestion or irrigation with hypotonic fluids, renal failure, syndrome of inappropriate antidiuretic hormone secretion (SIADH r/t cancer, trauma, stroke), hyperglycemia, heart failure

Signs and symptoms of hypernatremia

CNS: short attention span; agitation, confusion, as the sodium continues to increase: seizures, with fluid overload: lethargy, drowsiness, to coma Musculoskeletal S&S: mild increase muscle twitching & irregular muscle contractions occur, as it continues to increase there is increased weakness, diminished reflexes Cardiovascular S&S: increase in pulse rate, peripheral pluses are difficult to palpate & are easily block, hypotension & severe orthostatic hypotension with hypovolemia; with hypervolemia bounding pulses, distended neck veins, diastolic BP will increase. Renal: S&S: decreased urinary output, dry skin, rough red tongue, dry sticky mucous membranes, low grade fever, thirst

Hyponatremia Signs and Symptoms by body systems

Cerebral and Neuromuscular S&S: headache, irritability, disorientation and short attention span, muscle twitching, tremors, weakness, as the sodium continues to drop you will see delirium, psychosis, coma, seizures. GI S&S: increase motility causing nausea, diarrhea, and abdominal cramping Cardiovascular S&S: responds with hypovolemia (decreased plasma volume) including rapid, weak & thready pulse, peripheral pulses are difficult to palpate & easily block with slight pressure, flat neck veins, decrease BP, severe hypotension which leads to dizziness. With hypervolemia (fluid overload with dilutional) full bounding pulses that are difficult to block. Renal S&S: increased urinary output, decreased specific gravity

Priority nursing intervention

Determine the etiology. Is it r/t a fluid gain or an electrolyte loss? Aim of therapy is not to return serum Na levels to normal too quickly rather raise enough to alleviate S&S & complications *The priority nursing care for the patient is monitoring the patient's response to therapy to prevent hypernatremia & fluid overload.*

Sodium dietary sources

Dietary sources: canned soups and vegetables, cheese, ketchup, processed meats, table salt, salty snack foods, seafood

Nursing intervention hyponatremia

Drug Therapy: Reducing drugs that increase sodium loss such as loop & thiazide diuretics Hyponatremia occurs by fluid deficit: give IV saline solutions Hyponatremia occurs by fluid excess: give drugs that promote the excretion of water rather than sodium such as conivaptan (Vaprisol) Nutritional therapy can restore normal sodium balance: collaborate with dietitian to teach patients foods to increase in the diet. Assess lab data, assess I&O, mucous membranes, skin turgor Encourage intake of high sodium foods Assess edema: press finger over sternum or other bony prominence 5-10 seconds - remove - visible fingerprint (sign of intracellular H2O excess, peripheral edema is fluid in the interstitial space) Syndrome of inappropriate ADH secretion SIADH = fluid restriction - help pt comply with restriction 1000ml-1200ml/24hrs Irrigate N/G with NS, replace body fluids

Imbalance: Hypernatremia Na+ > 145mEq/L

Etiology of Hypernatremia Actual sodium excesses: hyperaldosteronism, kidney failure, corticosteroids, Cushing's syndrome; excessive ingestion of sodium, excessive intake of sodium-containing IV fluids Relative sodium excesses: NPO; water loss, increased rate of metabolism, fever, hyperventilation, infection, excessive diaphoresis, watery diarrhea, dehydration diabetes insipidus with inadequate H2O intake Note: Diabetes insipidus is a metabolic disorder due to injury of the pituitary which results in deficient ADH release which causes failure of tubular reabsorption of H2O in the kidneys which causes passage of large amounts of water

Imbalance: Hyponatremia - serum Na+ level < 136 mEq/L

Etiology of Hyponatremia Results from sodium loss, water gain (dilutional hyponatremia), or inadequate intake of sodium.

Sodium

Na+ 136-145 mEq/L Found primarily extracellular (90%); is regulated by dietary intake & aldosterone secretion

Hypernatremia nursing intervention

Priority nursing care is to monitor the patient's response to therapy & prevent hyponatremia & dehydration. Rapid correction can result in cerebral edema, seizures, and permanent neurological damage When caused by fluid loss: give hypotonic IV solutions When caused by poor renal excretion: administer diuretics Nutrition Therapy: ensure adequate water intake; restrict sodium intake in the diet & monitor foods high in sodium, assess I&O Offer patient fluids hourly - should have 6-8 8 (240ml) oz glasses daily Assess IV fluids: avoid hypertonic solutions Administer H2O with tube feedings

Sodium functions and regulations

Regulated by the kidneys Maintain fluid balance, & the effect on serum concentration Controls & regulates ECF volume Loss or gain usually accompanied by a loss or gain of water. Where sodium goes water Works in combination with CL to maintain blood volume Important regulation of acid base balance as sodium bicarbonate (bicarb) Participates in muscle contraction & transmission of nerve impulses Low sodium levels inhibit the secretion of ADH and NP & triggers aldosterone secretion which in turn will increase kidney reabsorption of sodium & enhance water loss. High sodium levels inhibit aldosterone secretion & stimulate ADH and NP. Excreted urine, sweat & feces Combination of Na+ & Cl- in water constitutes a saline solution

Hyponatremia signs and symptoms

S&S usually do not appear until Na+ < 125 mEq/L and S&S vary depending on how rapid changes in Na occur. Pt's having acute decrease in serum Na levels have higher mortality rates than a patient who more slowly develop hyponatremia. In dilutional hyponatremia (water gain) the S&S are similar to those of fluid excess

Patient profile hypernatremia

The major symptom of hypernatremia is thirst. The absence of thirst in conscious patients with hypernatremia suggests an impaired thirst mechanism. Patients with difficulty communicating may be unable to express thirst or obtain access to water. The major signs of hypernatremia result from CNS dysfunction due to brain cell shrinkage. Confusion, neuromuscular excitability, hyperreflexia, seizures, or coma may result. Cerebrovascular damage with subcortical or subarachnoid hemorrhage and venous thromboses are common among patients who died of severe hypernatremia. In chronic hypernatremia, osmotically active substances occur in CNS cells (idiogenic osmoles) and increase intracellular osmolality. Therefore, the degree of brain cell dehydration and resultant CNS symptoms are less severe in chronic than in acute hypernatremia. When hypernatremia occurs with abnormal total body Na, the typical symptoms of volume depletion or overload are present (see Volume Depletion and see Volume Overload). Patients with renal concentrating defects typically excrete a large volume of hypotonic urine. When losses are extrarenal, the route of water loss is often evident (eg, vomiting, diarrhea, excessive sweating), and the urinary Na concentration is low.

Etiology of Imbalance

There are many causes of electrolyte imbalances but they can be organized into groupings in terms of the relationship of the electrolytes to body water Gain of water / loss of water Gain of electrolytes / loss of electrolytes

Electrolytes

When studying electrolytes it is important that you understand the normal function of the electrolyte. Next you need to know the normal blood value of the electrolyte so that when you get a value you can decide if it Above normal - hyper Below normal - hypo Imbalances can occur in any body tissue