Medical Surgical Nursing Megan Rohm, MNc, BSN, RN-BC Today: Introduce ourselves Introduce the course -Syllabus Fluids and Electrolytes

Medical Surgical Nursing Unit One Topics: Fluids and Electrolytes Immune System

Unit 1 Fluid and Electrolytes MeganRohm, BSN,RN Acknowledgements to Elsevier

Unit 1 Fluid and Electrolytes Objectives: Explain how water balance and electrolyte balance are interdependent List, describe and compare the body fluid compartments Discuss active and passive transport processes and give examples of each Discuss the role of specific electrolytes in maintaining homeostasis Describe the cause and effect of deficits and excesses of sodium, potassium, chloride, calcium, magnesium, & phosphorus Discuss the role of the nursing process in maintaining fluid and electrolyte balances. Discuss how the very young, very old, and obese patient are at risk for fluid volume deficit.

Homeostasis State of equilibrium in body Naturally maintained by adaptive responses Body fluids and electrolytes are maintained within narrow limits

Water Content of the Body 60% of body weight in adult 45% to 55% in older adult 70% to 80% in infants Varies with gender, body mass, and age

Fluid Balance

Compartments Intracellular fluid (ICF) _______ ______ ______cell membrane Extracellular fluid (ECF) Interstitial = tissue ______________________capillary membrane Intravascular (plasma)

Fluid Compartments of the Body

Extracellular Fluid (ECF) One third of body fluid 3 major components Interstitial fluid Intravascular Transcellular fluid over or across the cells

Interstitial Component Fluid btwn cells Surrounds cells Transport medium for nutrients, gases, waste products and other substances btwn blood and body cells Also acts as a back up fluid reservoir

Fluid Regulation How does movement from space to space occur? Diffusion Osmosis Filtration Active transport

Fluid Regulation Diffusion Movement of solutes from an area of higher concentration to an area of lower concentration in a solution and or across a permeable membrane This movement occurs until near equal state

Fluid Regulation Osmosis Now with water.

Osmosis VS. Diffusion Osmosis Diffusion Low to high Water potential High to low Movement of particles

Fluid Regulation Filtration Water pushing against the confining walls of a space

Electrolytes Substances whose molecules dissociate into ions (charged particles) when placed into water Cations: positively charged Anions: negatively charged

Electrolyte Composition ICF Prevalent cation is K+ Prevalent anion is PO43- ECF Prevalent cation is Na+ Prevalent anion is Cl-

Regulation of Electrolytes Active transport Allows molecules to move against concentration and osmotic pressure to areas of higher concentration

Active Transport: Sodium–Potassium Pump Fig. 17-5 Copyright © 2007, 2004, 2000, Mosby, Inc., an affiliate of Elsevier Inc. All Rights Reserved.

Fluid Movement in Capillaries Amount and direction of movement determined by Capillary hydrostatic pressure Plasma oncotic pressure Interstitial hydrostatic pressure Interstitial oncotic pressure

Fluid Exchange Between Capillary and Tissue Fig. 17-8

Osmolality Concentration of body fluids- affects movement of fluid by osmosis. Reflects hydration status Measured by serum and urine Solutes measured-mainly urea, glucose, & sodium

Osmolality Increases in serum level Serum value 280-300 mOsm/kg Urine value 250-900 mOsm/kg Increases in serum level Free water loss Elevated Na Hyperglycemia Uremia

Fluid Volume Shifts Normally fluid shifts btwn intracellular and extracellular compartments to maintain equilibrium btwn spaces Fluid not lost from body, but not available for use in either compartment- considered third-space fluid shift (third-spacing) Enters interstitial compartment

Causes of Third-Spacing Burns Peritonitis Bowel obstruction Massive bleeding into joint or cavity Liver or renal failure Lowered plasma proteins Increased capillary permeability

Assessment of Third-Spacing More difficult – fluid sequestered in deeper structures Signs/Symptoms Decreased urine output with adequate intake Increased HR Decreased BP Increased weight Pitting edema, ascites

Phases of Third-Spacing Loss phase Lasts 48-72 hours Symptoms of FVD Reabsorption phase Fluid gradually reabsorbed after problem subsides FVO possible Monitor VS, I&O, Wt, and breath sounds

Treatment Treat underlying cause if possible Close observation of VS Monitor I & O more frequently Daily weights Measure abdominal girth in ascites Measure extremities if necessary Monitor lab values albumin level important

Treatment Goals Stabilized I & O Stabilized weight VS within normal range Resolution of third-spacing

Extracellular Fluid Volume Imbalances ECF volume deficit (hypovolemia) Abnormal loss of normal body fluids (diarrhea, fistula drainage, hemorrhage), inadequate intake, or plasma-to-interstitial fluid shift Treatment: replace water and electrolytes with balanced IV solutions

Fluid Volume Deficit Hypovolemia Abnormally low volume of body fluid in intravascular and/or interstitial compartments Causes Vomiting Diarrhea Fever Excess sweating Burns Diabetes insipidus Inadequate intake Hemorrhage Overuse of diuretics Third spacing

Fluid volume deficit What happens Output > Intake Water extracted from ECF ECF hypertonic (water moves out of cell  cell dehydration) + osmotic pressure increased (stimulates thirst preceptor in hypothalamus) ICF hypotonic with decreased osmotic pressure  posterior pituitary secretes more ADH Decreased ECF volume adrenal glands secrete Aldosterone

Signs and Symptoms Acute weight loss Decreased skin turgor Oliguria Concentrated urine Weak, rapid pulse Capillary filling time elongated Decreased BP Increased pulse Sensations of thirst, weakness, dizziness, muscle cramps

Labs Increased HCT Increased BUN Increased serum osmolality Increased urine osmolality Increased specific gravity Decreased urine volume, dark color

Significant Points Dehydration – one of most common disturbances in infants and children Additional S/S Sunken eyeballs Depressed fontanels Significant wt loss

Significant Points Older Adult Vein filling better indicator than skin turgor Have additional health problems Take various medications May ↓ intake to prevent incontinence

Nursing Management Nursing Diagnoses Hypovolemia Deficient fluid volume Decreased cardiac output Potential complication: hypovolemic shock

Interventions Major goal prevent or correct abnormal fluid volume status before ARF occurs Encourage fluids IV fluids Isotonic solutions (0.9% NS or LR) until BP back to normal, then hypotonic (0.45% NS) Monitor I & O, urine specific gravity, DAILY WEIGHTS

Interventions Monitor skin turgor Monitor VS and mental status Goal: Normal skin turgor, increased UOP with normal specific gravity, normal VS, clear sensorium, good oral intake of fluids, labs WNL

Regulation of Water Balance Antidieuretic Hormone (ADH) Hold on to water Aldosterone Increases Na+ retention

Where is a lot of this happening in the body?

Renal Regulation regulating fluid and electrolyte balance Adjusting urine volume Selective reabsorption of water and electrolytes Renal tubules are sites of action of ADH and aldosterone

Effects of Stress on F&E Balance Fig. 17-10

Gastrointestinal Regulation Oral intake accounts for most water Small amounts of water are eliminated by gastrointestinal tract in feces Diarrhea and vomiting can lead to significant fluid and electrolyte loss

Extracellular Fluid Volume Imbalances Fluid volume excess (hypervolemia) Excessive intake of fluids, abnormal retention of fluids (CHF), or interstitial-to-plasma fluid shift Treatment: remove fluid without changing electrolyte composition or osmolality of ECF

Causes Excessive isotonic or hypotonic IV fluids Heart failure Renal failure- urinary Liver failure, cirrhosis Long-term use corticosteroids

Signs/Symptoms Headache, confusion, lethargy Edema Distended neck veins Bounding pulse, Polyuria Dyspnea, crackles, pulmonary edema Wt. Gain Seizures, coma

Nursing Management Nursing Diagnoses Hypervolemia Excess fluid volume Ineffective airway clearance Risk for impaired skin integrity Disturbed body image Potential complications: pulmonary edema, ascites

Nursing Management Nursing Implementation Monitor cardiovascular changes Assess respiratory status and monitor changes Daily weights Skin assessment

Nursing Management Nursing Implementation Neurologic function LOC PERLA Voluntary movement of extremities Muscle strength Reflexes

Electrolyte Imbalances Refer to charts available on Angel

Electrolyte Disorders Signs and Symptoms Excess Deficit Sodium (Na) Hypernatremia Thirst CNS deterioration Increased interstitial fluid Hyponatremia Potassium (K) Hyperkalemia Ventricular fibrillation ECG changes CNS changes Hypokalemia Bradycardia

Electrolyte Disorders Signs and Symptoms Excess Deficit Calcium (Ca) Hypercalcemia Thirst CNS deterioration Increased interstitial fluid Hypocalcemia Tetany Chvostek’s, Trousseau’s signs Muscle twitching CNS changes ECG changes Magnesium (Mg) Hypermagnesemia Loss of deep tendon reflexes (DTRs) Depression of CNS Depression of neuromuscular function Hypomagnesemia Hyperactive DTRs

Sodium Normal 135-145 mEq/L Plays a major role in ECF volume and concentration Generation and transmission of nerve impulses Acid–base balance

Differential Assessment of ECF Volume

Hypernatremia Elevated serum sodium occurring with water loss or sodium gain Causes hyperosmolality leading to cellular dehydration Primary protection is thirst from hypothalamus

Signs/Symptoms Early: Generalized muscle weakness, faintness, muscle fatigue, HA Moderate: Confusion, thirst Late: Edema, restlessness, thirst, hyperreflexia, muscle twitching, irritability, seizures, possible coma Severe: Permanent brain damage, hypertension, tachycardia, N & V

Nursing Management Nursing Diagnoses Risk for injury Potential complication: seizures and coma leading to irreversible brain damage

Nursing Management Nursing Implementation Treat underlying cause Free water to replace ECF volume If oral fluids cannot be ingested, IV solution of 5% dextrose in water or hypotonic saline (gradual) Diuretics

Hyponatremia Results from excess loss of Na containing fluids or from water excess: GI losses, diuretic therapy, severe renal dysfunction, severe diaphoreses, narcotic use Manifestations, S/S Confusion, nausea, vomiting, seizures, decreased BP, headache, muscle twitching, cramps

Nursing Management Nursing Diagnoses Risk for injury Potential complication: severe neurologic changes

Nursing Management Nursing Implementation Caused by water excess Fluid restriction is needed Severe symptoms (seizures) Give small amount of IV hypertonic saline solution (3% NaCl) Abnormal fluid loss Fluid replacement with sodium-containing solution

Potassium Normal 3.5-5.5 mEq/L Major ICF cation Necessary for Transmission and conduction of nerve and muscle impulses Maintenance of cardiac rhythms Acid–base balance

Potassium Sources Fruits and vegetables (bananas and oranges) Salt substitutes Potassium medications (PO, IV) Stored blood

Hyperkalemia High serum potassium caused by Massive intake of K Impaired renal excretion Shift from ICF to ECF Common in massive cell destruction Burn, crush injury, or tumor lysis

Hyperkalemia Manifestations, S/S Weak or paralyzed skeletal muscles ECG changes; Ventricular fibrillation or cardiac standstill Abdominal cramping or diarrhea

Nursing Management Nursing Diagnoses Risk for injury Potential complication: dysrhythmias

Nursing Management Nursing Implementation Eliminate oral and parenteral K intake Increase elimination of K (diuretics, dialysis, Kayexalate)

Nursing Management Nursing Implementation Force K from ECF to ICF by IV insulin or sodium bicarbonate Reverse membrane effects of elevated ECF potassium by administering calcium gluconate IV

Hypokalemia Low serum potassium caused by Abnormal losses of K+ via the kidneys or gastrointestinal tract Magnesium deficiency Metabolic alkalosis

Hypokalemia Manifestations Most serious are cardiac Skeletal muscle weakness Weakness of respiratory muscles Decreased gastrointestinal motility

Nursing Management Nursing Diagnoses Risk for injury Potential complication: dysrhythmias

Nursing Management Nursing Implementation KCl supplements orally or IV Slowly K is an irritant Should not exceed 40 mEq/hr To prevent hyperkalemia and cardiac arrest

Nursing Management Nursing Implementation Hypertonic glucose solution Monitor I&Os VS, cardiac rhythm Muscle strength Bowel sounds

Calcium Normal 4.5-5.5 mEq/L Obtained from ingested foods More than 99% combined with phosphorus and concentrated in skeletal system the other 1% is in ECF and soft tissues

Calcium Bones are readily available store Blocks sodium transport and stabilizes cell membrane

Calcium Functions Transmission of nerve impulses Myocardial contractions Blood clotting Formation of teeth and bone Muscle contractions

Calcium Balance controlled by Parathyroid hormone Calcitonin Vitamin D

Hypercalcemia High serum calcium levels caused by Hyperparathyroidism (two thirds of cases) Malignancy Vitamin D overdose Prolonged immobilization

Hypercalcemia Manifestations, S/S Decreased memory Confusion, fatigue, coma Anorexia, constipation Muscle weakness, loss of muscle tone Polyuria & predisposes to renal calculi

Nursing Management Nursing Diagnoses Risk for injury Potential complication: dysrhythmias death

Nursing Management Nursing Implementation Excretion of Ca with loop diuretic Hydration with isotonic saline infusion Synthetic calcitonin Mobilization

Hypocalcemia Low serum Ca levels caused by Decreased production of PTH Acute pancreatitis Multiple blood transfusions Alkalosis Decreased intake

Hypocalcemia Manifestations Positive Trousseau’s or Chvostek’s sign Laryngeal stridor Dysphagia Tingling around the mouth or in the extremities

Tests for Hypocalcemia Fig. 17-15

Nursing Management Nursing Diagnoses Risk for injury Potential complication: fracture or respiratory arrest

Nursing Management Nursing Implementation Treat cause Oral or IV calcium supplements Not IM to avoid local reactions Treat pain and anxiety to prevent hyperventilation-induced respiratory alkalosis

Phosphate Primary anion in ICF Essential to function of muscle, red blood cells, and nervous system Deposited with calcium for bone and tooth structure

Phosphate Involved in acid–base buffering system, ATP production, and cellular uptake of glucose Maintenance requires adequate renal functioning Essential to muscle, RBCs, and nervous system function

Hyperphosphatemia High serum PO43- caused by Acute or chronic renal failure Chemotherapy Excessive ingestion of phosphate or vitamin D

Hyperphosphatemia Manifestations Calcified deposition in soft tissue such as joints, arteries, skin, kidneys, and corneas Neuromuscular irritability and tetany

Hyperphosphatemia Management Identify and treat underlying cause Restrict foods and fluids containing PO43- Adequate hydration and correction of hypocalcemic conditions

Hypophosphatemia Low serum PO43- caused by Malnourishment/malabsorption Alcohol withdrawal Use of phosphate-binding antacids During parenteral nutrition with inadequate replacement

Hypophosphatemia Manifestations CNS depression Confusion Muscle weakness and pain Dysrhythmias Cardiomyopathy

Hypophosphatemia Management Oral supplementation Ingestion of foods high in PO43- IV administration of sodium or potassium phosphate

Magnesium 50% to 60% contained in bone Coenzyme in metabolism of protein and carbohydrates Factors that regulate calcium balance appear to influence magnesium balance

Magnesium Acts directly on myoneural junction Important for normal cardiac function

Hypermagnesemia High serum Mg caused by Increased intake or ingestion of products containing magnesium when renal insufficiency or failure is present

Hypermagnesemia Manifestations Lethargy or drowsiness Nausea/vomiting Impaired reflexes Respiratory and cardiac arrest

Hypermagnesemia Management Prevention Emergency treatment IV CaCl or calcium gluconate Fluids to promote urinary excretion

Hypomagnesemia Low serum Mg caused by Prolonged fasting or starvation Chronic alcoholism Fluid loss from gastrointestinal tract Prolonged parenteral nutrition without supplementation Diuretics

Hypomagnesemia Manifestations Confusion Hyperactive deep tendon reflexes Tremors Seizures Cardiac dysrhythmias

Hypomagnesemia Management Oral supplements Increase dietary intake Parenteral IV or IM magnesium when severe

IV Fluid Replacement Purposes Maintenance Replacement When oral intake is not adequate Replacement When losses have occurred

IV Fluid Reference

IV Fluids Hypotonic More water than electrolytes Pure water lyses RBCs Water moves from ECF to ICF by osmosis Usually maintenance fluids

IV Fluids Isotonic Expands only ECF No net loss or gain from ICF

IV Fluids Hypertonic Require frequent monitoring of Initially expands and raises the osmolality of ECF when it shifts fluids from ICF & ECF into vascular component- expands blood volume Require frequent monitoring of Blood pressure Lung sounds Serum sodium levels

Normal Saline (NS) Isotonic No calories 30% stays in intravascular space

Normal Saline (NS) Expands IV volume Does not change ICF volume Preferred fluid for immediate response Risk for fluid overload higher Does not change ICF volume Blood products Compatible with most medications

Lactated Ringer’s Isotonic More similar to plasma than NS Expands ECF Has less NaCl Has K, Ca, PO43-, lactate (metabolized to HCO3-) Expands ECF

Plasma Expanders Stay in vascular space and increase osmotic pressure Colloids (protein solutions) Packed RBCs Albumin Plasma