Fluids & Electrolytes - NCM 53 Lec - PDF

MANAGEMENT OF FLUID AND ELECTROLYTE & ACID-BASE DISTURBANCES Fluid Volume Deficit (FVD): Hypovolemia CLINICAL MANIFESTATIONS » Fluid volume deficit is a decrease in Acute weight loss intravascular, interstitial, and/or Poor skin turgor intracellular fluid in...

MANAGEMENT OF FLUID AND ELECTROLYTE & ACID-BASE DISTURBANCES Fluid Volume Deficit (FVD): Hypovolemia CLINICAL MANIFESTATIONS » Fluid volume deficit is a decrease in Acute weight loss intravascular, interstitial, and/or Poor skin turgor intracellular fluid in the body Postural or orthostatic hypotension (a » The result of excessive fluid losses, drop of more than 15 mmHg in systolic insufficient fluid intake, or failure of blood pressure) regulatory mechanisms and fluid shifts Oliguria, concentrated urine within the body Flattened neck veins; weak, rapid heart » It occurs when water and electrolytes are rate lost in the same proportion as they exist in Decreased CVP normal body fluids Increased temperature » Dehydration – refers to loss of water alone with increased serum sodium levels Thirst Anorexia, nausea PATHOPHYSIOLOGY Lassitude » Most common cause: Clammy skin excessive loss of GI fluids from Muscle weakness and cramps vomiting, diarrhea, GI suctioning, intestinal fistulas, and intestinal CATEGORIES drainage » Other causes: » Mild FVD – loss of 1-2L of water or 2% of diuretics, renal disorders, endocrine body weight disorders, excessive exercise, hot » Moderate FVD – loss of 3-5L of water or 5% environment, hemorrhage, and of body weight chronic abuse of laxatives or enemas » Severe FVD – loss of 5-10L of water or 8% of » Other factors: body weight inadequate fluid intake include inability to access fluids, inability to request or to swallow fluids, oral trauma, or altered thirst mechanisms » Older adults are at particular risk for fluid volume deficit » Electrolytes often are lost along with fluid, resulting in an isotonic fluid volume deficit » When both water and electrolytes are lost, the serum sodium level remains normal, although levels of potassium may fall » Fluid is drawn into the vascular compartment from the interstitial spaces as the body attempts to maintain tissue perfusion » This eventually depletes fluid in the DISORDERS OF WATER BALANCE: DEHYDRATION intracellular compartment » Hypovolemia stimulates regulatory mechanisms to maintain circulation » Thirst mechanism is stimulated » ADH and aldosterone are released, prompting sodium and water retention by the kidneys » Severe fluid loss, as in hemorrhage, can lead to shock and cardiovascular collapse Dehydration - Water loss exceeds water intake and the body is in negative - Causes include hemorrhage, severe burns, prolonged vomiting or diarrhea, profuse 1 | NCM 53 Lec ALEONIE ISABYLL G. DINGDING, SN III  MANAGEMENT OF FLUID AND ELECTROLYTE & ACID-BASE DISTURBANCES sweating, water deprivation, and diuretic Severe fluid deficit with loss of abuse electrolytes - Signs and symptoms: cottonmouth, thirst, o Carbohydrate/electrolyte dry flushed skin, and oliguria solution (sports drink, ginger - Prolonged dehydration may lead to ale) weight loss, fever, and mental confusion o Rehydrating solution (Pedialyte, - Other consequences include hypovolemic Rehydralyte) shock and loss of electrolytes Provide sodium, potassium, chloride, and calories to help meet metabolic Fluid Volume Shift: Third Spacing (FVD) need » Assessing the extent of FVD resulting from » IV therapy third spacing is difficult When the fluid deficit is severe, or » May not be reflected in weight or intake and the patient is unable to ingest fluids output records 0.9% NaCl or Ringer’s Solution – use » May not become apparent until after organ to expand customer volume in malfunction occurs hypotensive patients or to replace » Delays in recognition and treatment can abnormal losses which are usually lead to irreversible shock and multiorgan isotonic in nature system failure Blood is given when volume loss is » Daily weights may be helpful in uncovering due to blood loss third-spaced fluids D5 0.45% NaCl or 0.45% NaCl – given to provide water to treat total ASSESSMENT & DIAGNOSTIC FINDINGS body water deficits; used as » Osmolality greater than 295 mOs/kg maintenance solutions = normal » Na+ greater than 145 mEq/L tensive state; provide additional » BUN greater than 25 mg/dl electrolytes such as potassium, a » BUN:Creatinine ratio is greater than 20:1 buffer (lactate or acetate) as (N/V = 10:1-15:1) / (Creatinine = 0.5-1.1 [F]; needed, and water 0.6-1.2 [M]) o Dextrose – provide minimal » Hct greater than 55% number of calorie » Urine specific gravity greater than 1.030 » Changes in serum electrolytes - Hypokalemia occurs with GI and renal losses - Hyperkalemia occurs with adrenal insufficiency - Hyponatremia occurs with increased thirst and ADH release - Hypernatremia results from increased insensible losses and diabetes insipidus MEDICAL MANAGEMENT » Oral rehydration NURSING DIAGNOSIS Safest and most effective treatment Fluid volume deficit r/t inadequate fluid for those who can take oral fluids intake Adults = minimum of 1500ml/day or Impaired tissue integrity r/t fluid deficit 30ml/kg of body weight Altered mucous membranes r/t Mild fluid deficits with minimal dehydration electrolytes = water alone may be Altered tissue perfusion, renal r/t used for fluid replacement decreased renal blood flow and low urine output s/t FVD or hypovolemia 2 | NCM 53 Lec ALEONIE ISABYLL G. DINGDING, SN III  MANAGEMENT OF FLUID AND ELECTROLYTE & ACID-BASE DISTURBANCES NURSING RESPONSIBILITIES Identify presence of risk factors (age, malnutrition, meds, acute & chronic illness) Rehydration Report a urine output of less than 30 m/hour (N/V = 30–60 ml) Weigh daily under standard conditions (time of day, clothing, scale) Monitor for changes in level of consciousness and mental status. Monitor serum creatinine, BUN, and cardiac enzymes, Turn at least every 2 hours. Provide good skin care. Keeping the bed in a low position, using side rails as needed, Teach patient and family members how to reduce orthostatic Hypotension DIAGNOSTIC FINDINGS Fluid Volume Excess (FVE): Hypervolemia » Plasma osmolality less than 275mOs/kg » Fluid volume excess results when both water » Na+ less than 135 mEq/L and sodium are retained in the body. » Hematocrit less than 45% » Can lead to excess intravascular fluid » Spec. gravity less than 1.010 (hypervolemia) and excess interstitial fluid » BUN less than 8mg/dl (edema). » Causes: Third Spacing (Edema) Overload (excess water and sodium - Collection of excess fluids in body tissue intake) - Causes: 1. increased capillary pressure Failure to excrete fluids (hydrostatic pressure) Excessive sodium intake 2. increased capillary filtration pressure 3. decreased plasma colloid osmotic PATHOPHYSIOLOGY » Results from conditions that cause pressure/oncotic pressure retention of both sodium and water: 4. increased capillary permeability heart failure, cirrhosis of the liver, renal 5. compromised lymphatic function failure, adrenal gland disorders, corticosteroid administration, and TREATMENT stress conditions causing the release of » Diuretic therapy ADH and aldosterone. Loop diuretics (severe) – Furosemide Other causes include an excessive intake of sodium-containing foods, drugs that (Lasix) cause sodium retention, and the Thiazide & Thiazide-like diuretics – administration of excess amounts of Hydrochlorothiazide (HydroDIURIL, 0.9% NaCl or Ringer’s solution, SIADH Oretic) Potassium-sparing diuretics – Spironolactone (Aldactone) » Remove excess fluids (pericardiocentesis, thoracentesis, paracentesis) 3 | NCM 53 Lec ALEONIE ISABYLL G. DINGDING, SN III  MANAGEMENT OF FLUID AND ELECTROLYTE & ACID-BASE DISTURBANCES » D/C administration of sodium-containing fluids » Treatment of FVE usually involves dietary restriction of sodium » Fluid restriction » Dialysis – renal failure Ways to decrease dependent edema: o Change position frequently o Avoid restrictive clothing NURSING DIAGNOSIS o Avoid crossing the legs when sitting Fluid volume excess o Wear support stockings or hose Ineffective breathing patterns o Elevate feet and legs when sitting Impaired gas exchange Using additional pillows or a recliner to sleep, to relieve orthopnea Risk for impaired tissue integrity (peripheral edema) Monitor oxygen saturation levels and arterial blood gases (ABGs) INTERVENTIONS Strict MIO daily Assess urine output hourly (balanced I&O) Inspection and daily measurement of circumference of involved area Application of finger pressure to assess for pitting edema Electrolyte Disturbance PLASMA RANGES FOR ELECTROLYTES Obtain daily weights at the same time of § Sodium (Na) 135-145 mEq/L day, using approximately the same § Chloride (Cl) 98-106 mEq/L clothing and a balanced scale § Potassium (K) 3.5-5.0 mEq/L Administer oral fluids cautiously, § Calcium (Ca) 4.5-5.6 mEq/L § Phosphorus (P) 1.7-2.6 mEq/L adhering to any prescribed fluid § Magnesium (Mg) 1.3-2.5 mEq/L restriction. Provide oral hygiene at least every 2 hours. Sodium Imbalances Teach patient and significant others Sodium about the sodium restricted diet » 135-145 mEq/L Reposition the patient at least every 2 » 90% of extracellular cations; most abundant hours ion in ECF » The primary determinant of ECF osmolality; primary regulator of ECF volume 4 | NCM 53 Lec ALEONIE ISABYLL G. DINGDING, SN III  MANAGEMENT OF FLUID AND ELECTROLYTE & ACID-BASE DISTURBANCES » Functions in establishing the electrochemical PATHOPHYSIOLOGY state necessary for muscle contraction and » Decreased excitability of the membranes the transmission of nerve impulses and due to delayed membrane depolarization » If uncorrected K+ moves out of the cell regulating acid-base balance leading to K+ imbalance » Level in blood controlled by: » Excitable tissues vary in there response to Aldosterone – increases renal decreased Na+ reabsorption ADH – if sodium too low, ADH release SIGNS & SYMPTOMS stops § ↓ 125 mEq/L = symptomatic Atrial natriuretic peptide – increases § GI: N/V, abdominal cramping, anorexia, renal excretion feelings of exhaustion » The kidney is the primary regulator of § Cardio: orthostatic hypotension, weak, sodium balance in the body thready pulse, tachycardia § Respiratory: crackles, SOB, dyspnea § Skin: dry skin; dry tongue & mucous membrane § Neuro: headache & apprehension = early; confusion, seizures, coma death = severe DIAGNOSTIC EXAMS § Serum Sodium less than 135 mEq/L § Serum Chloride less than 98 mEq/L § Urine Sodium less than 40 mEq /L § Serum osmolality less than 275 mEq/L A. Hyponatremia § Causes: MEDICAL MANAGEMENT o Serum sodium of less than 135 Raising the ratio of sodium to water in the ECF mEq/L § ↓ 125 mEq/L = 0.9 NaCl or LR o From a loss of sodium from the § ↓ 115 mEq/L = 3% NaCl body, but it may also be caused by § Diuretic (Furosemide) to prevent water gains that dilute ECF pulmonary § Fluid overload – for normal or excess ECF volume § Demeclocycline antagonizes ADH in SIADH § Vasopressor receptor antagonists block the activity of ADH o Conivaptan (Vaprisol) given IV o Tolvaptan (Samsca) given orally § In mild hyponatremia caused by water excess, fluid restriction may be the only treatment NURSING DIAGNOSIS & MANAGEMENT § Risk for hyponatremia r/t unreplaced loss or limited oral intake o If Na+ level is greater than 125 mEq/L, encourage intake of 30-60 ml of clear liquids 5 | NCM 53 Lec ALEONIE ISABYLL G. DINGDING, SN III  MANAGEMENT OF FLUID AND ELECTROLYTE & ACID-BASE DISTURBANCES o To prevent Na+ loss, irrigate PATHOPHYSIOLOGY nasogastric tubes & wounds with Two regulatory mechanisms protect the body isotonic saline from hypernatremia: release of ADH so more water is o Treat nausea with prophylactic anti- retained by the kidneys emetics thirst mechanism - to increase the § Hyponatremia r/t vomiting , diarrhea, intake of water. gastric suctioning, burns, SIADH Hypernatremia is not a problem in an alert o Restore sodium balance person who has access to water, can sense o Well–balanced diet if on NGT, add thirst, and is able to swallow. extra salt » Causes hyperosmolality of the ECF= ↑155 o Decrease thirst that accompanies mEq/L brain cells shrink = can cause coma fluid restriction by offering ice and seizures chips, cold drinks & frequent oral » Na+ molecules compete with calcium in the care slow calcium channels of the heart, o Record urine output accurately resulting in decreased myocardial o Na+ level below 125 notify physician contractility o 3% saline (hypertonic saline) must be given very slowly thru piggyback in a SIGNS & SYMPTOMS large vein to decrease the risk of § Thirst - first manifestation hypernatremia, pulmonary overload § Initial lethargy, weakness, and & phlebitis irritability can progress to seizures, coma, o Initiate safety & seizure precaution and death in severe hypernatremia § Risk for ineffective cerebral tissue perfusion MEDICAL MANAGEMENT o Monitor serum electrolytes and Decreasing the ratio of sodium to water in the serum osmolality ECF o Assess for neurologic changes, such as lethargy, altered level of § If water deficit - oral or IV isotonic consciousness, confusion, and solution 0.9% sodium chloride or convulsions. hypotonic 0.45% NaCl o Assess muscle strength and tone, § If sodium excess- 5% dextrose in water and deep tendon reflexes. § Diuretic – excretion of sodium B. Hypernatremia (hypertonic dehydration) § Desmopressin acetate (nasal spray) if § Serum sodium level greater than 145 due to diabetes insipidus mEq/L § Dietary sodium intake is often restricted § Sodium is gained in excess of water, or when water is lost in excess of sodium NURSING DIAGNOSIS & MANAGEMENT § Fluid volume deficit or fluid volume § Hypernatremia r/t decreased thirst, excess often accompany hypernatremia excessive administration of salt solutions, impaired excretion of Na & H2O § Impaired oral mucous membrane r/t lack of body water secondary to hypernatremia CLINICAL CONSDIERATIONS FOR NA+ ü Sodium causes water retention. ü One teaspoon of salt is equivalent to 2.3g of sodium. The daily sodium requirement is 2-4 g. 6 | NCM 53 Lec ALEONIE ISABYLL G. DINGDING, SN III  MANAGEMENT OF FLUID AND ELECTROLYTE & ACID-BASE DISTURBANCES ü Vomiting causes sodium and chloride losses, and diarrhea causes sodium, chloride and bicarbonate losses. ü Steroids promote sodium retention and thus, water retention. ü Cough medicine, sulfonamides and some antibiotics containing sodium can increase the serum sodium level. HYPONATREMIA HYPERNATREMIA § ↓ 135 mEq/L § ↑ 145 mEq/L § ECF becomes § ECF becomes hypoosmolar hyperosmolar PATHOPHYSIOLOGY § Fluid shifts from § Fluid shifts from » Hypokalemia alters the resting membrane ECF to ICF ICF to ECF potential, resulting in: § Intracellular § Cellular hyperpolarization (an increased negative edema dehydration charge within the cell) impaired muscle contraction. Potassium Imbalances » Therefore, the manifestations of Potassium hypokalemia involve changes in cardiac and muscle function » 3.5-5.0 mEq/L » Most abundant cations in ICF SIGNS & SYMPTOMS » Plays a vital role in cell metabolism and Decreased Excitability: Skeletal and Smooth cardiac and neuromuscular function Muscle » Helps maintain the resting membrane § leg cramps, skeletal muscle weakness, potential of nerve and muscle cells decrease reflexes, constipation, shallow » Also helps maintain normal ICF fluid volume respirations, SOB, apnea, respiratory » Helps regulate pH of body fluids when arrest exchanged for H+ Increased Excitability: Neurons and Cardiac » Controlled by aldosterone Muscles o Stimulates principal cells in renal § paresthesia, fatigue, irritability collecting ducts to secrete excess K+ § most serious: lethal ventricular » Dietary intake of potassium in the average arrhythmias; cardiac arrest adult is 50 to 100 mEq/day » The kidneys are the main source of potassium loss » Potassium imbalances affect transmission and conduction of nerve impulses, maintenance of normal cardiac rhythms, and contraction of skeletal and smooth muscle A. Hypokalemia MEDICAL MANAGEMENT § ↓ 3.5 mEq/L § Restore K+ levels § Common causes: o Oral or IV potassium chloride (KCl) o Inadequate K+ intake o Increased dietary intake of o K+ loss exceeds intake potassium. o Shift of K+ into cells o Consuming potassium-rich foods for mild hypokalemia 7 | NCM 53 Lec ALEONIE ISABYLL G. DINGDING, SN III  MANAGEMENT OF FLUID AND ELECTROLYTE & ACID-BASE DISTURBANCES NURSING DIAGNOSIS & MANAGEMENT » The most clinically significant problems § Hypokalemia r/t vomiting, decreased are the changes in cardiac conduction intake & others § Decreased cardiac output § Risk for imbalanced fluid volume § Activity intolerance § Risk for injury r/t muscle weakness and hypotension or seizures § Imbalanced nutrition: less than body requirements r/t insufficient intake of foods rich in K+ B. Hyperkalemia § An elevation of the K+ level greater than 5 mEq/L MEDICAL MANAGEMENT § Result from: To correct K+ level as quickly as possible to o Inadequate excretion of potassium prevent life-threatening consequences o Excessively high intake of potassium § IV calcium gluconate o A shift of potassium from the ICF to § Insulin & 50 g glucose to promote K+ the ECF uptake into cells § ß2-agonist such as albuterol may be given by nebulizer to temporarily push potassium into the cells § Sodium bicarbonate – to treat acidosis § Sodium polystyrene sulfonate (Kayexalate) o A resin that binds potassium in the GI tract, may be administered orally or rectally § Diuretics such as furosemide - to promote § Potassium excretion, if renal function is normal PATHOPHYSIOLOGY NURSING DIAGNOSIS & INTERVENTION » Impaired renal excretion of potassium is a primary cause of hyperkalemia § Risk for decreased cardiac output » The increased potassium concentration § Risk for activity intolerance outside the cell changes the normal ECF Administer fluids as ordered to promote renal and ICF ratio excretion of K+ » This results in increased cell excitability and changes in impulse transmission to the nerves and heart, skeletal muscles and GI tract. 8 | NCM 53 Lec ALEONIE ISABYLL G. DINGDING, SN III  MANAGEMENT OF FLUID AND ELECTROLYTE & ACID-BASE DISTURBANCES CLINICAL CONSDIERATIONS FOR K+ » Calcium levels are often reciprocal with ü Oral potassium should be taken with phosphorus levels food and/or 8 ounces of fluid. » Ionized calcium is essential for the processes: o Mild hypokalemia, 3.4 mEq/L, can be o stabilizing cell membranes avoided by eating foods rich in o regulating muscle contraction and potassium (fresh/dry fruits, fruit relaxation juices, vegetables, meats, nuts) o maintaining cardiac function ü IV potassium should be well diluted in IV o blood clotting solution. NEVER administer IV potassium » Regulated by the interaction of three as a bolus (IV push). It can cause cardiac hormones: arrest. o parathyroid hormone (PTH) ü Normal dose for IV potassium is 20-40 o calcitonin mEq in 1 liter of IV fluids to run for 8 o calcitriol (a metabolite of vitamin D) hours. LOW SERUM CALCIUM LEVELS ü Invert IV bags containing KCl several the parathyroid glands secrete PTH which times to ensure even distribution in the enables production of Calcitriol (from bag. kidneys) which facilitates: ü Do not add KCl to a hanging IV bag to o calcium release from the bones prevent giving a bolus dose. o absorption in the intestines ü Infiltration of IV potassium causes o and reabsorption by the kidneys HIGH SERUM CALCIUM LEVELS: sloughing of the SQ tissues and with the thyroid gland produce calcitonin prolonged use, phlebitis might occur. which: ü Potassium should NOT be administered if o inhibits the movement of calcium out the U/O is