Fluid, Electrolytes, Acid-Base Balance, and Intravenous Therapy

Chapter 3 Fluid, Electrolytes, Acid-Base Balance, and Intravenous Therapy Lesson 3.1 Fluid, Electrolytes, Acid- Base Balance, and Intravenous Therapy Theory Objectives (1 of 3)  Explain the various functions fluid performs in the body.  Describe the body’s mechanis...

Chapter 3 Fluid, Electrolytes, Acid-Base Balance, and Intravenous Therapy Lesson 3.1 Fluid, Electrolytes, Acid- Base Balance, and Intravenous Therapy Theory Objectives (1 of 3)  Explain the various functions fluid performs in the body.  Describe the body’s mechanisms for fluid regulation.  Describe three ways in which body fluids are continually being distributed among the fluid compartments.  Distinguish the signs and symptoms of various electrolyte imbalances.  Theory Objectives (2 of 3)  Discuss why the older adults have more problems with fluid and electrolyte imbalances.  Describe the disorders that cause specific fluid and electrolyte imbalances.  Compare the major causes of acid-base imbalances.  Apply interventions to correct an acid-base imbalance.  Theory Objectives (3 of 3)  Discuss the steps in managing an intravenous (IV) infusion.  Explain the measures used to prevent the complications of IV therapy.  Identify intravenous fluids that are isotonic and when they are used.  Interpret the principles of IV therapy. Clinical Practice Objectives (1 of 2)  Assess patients for signs of dehydration.  Correctly assess for and identify edema and signs of overhydration.  Apply knowledge of normal laboratory values in order to recognize electrolyte imbalances. Clinical Practice Objectives (2 of 2)  Perform interventions to correct an electrolyte imbalance.  Determine whether a patient has an acid-base imbalance.  Implement measures to prevent the complications of IV therapy.  Compare interventions for the care of a patient receiving total parenteral nutrition with one undergoing IV therapy.  Functions of Water  Transportation  Heat regulation  Maintenance of hydrogen (H+) balance  Medium for the enzymatic action of digestion Distribution and Regulation of Body Fluids  Osmoreceptors  Baroreceptors  Antidiuretic hormone (ADH)  Aldosterone  Brain natriuretic peptide or B-type natriuretic peptide (BNP) and Atrial natriuretic peptide (ANP) Movement of Fluid and Electrolytes (1 of 2)  Passive transport  Diffusion is the process by which substances move across the membrane until they are evenly distributed throughout the available space.  Osmosis is the movement of pure solvent (water) across a semipermeable membrane.  Filtration is the movement of water and solutes through a semipermeable membrane due to a pushing force (hydrostatic pressure) on one side of the membrane. Movement of Fluid and Electrolytes (2 of 2)  Active transport  Requires cellular energy  Moves molecules into cells against electrical or concentration gradients  Uses energy (ATP)-requiring pump Example: sodium-potassium pump  Fluid Imbalances  Exists when there is an excess (too much) or a deficit (too little) of water in the body.  Healthy kidney balances the amount of substances entering and leaving the blood  Illness affects fluid balance  Deficient Fluid Volume: Risk Factors  Impaired swallowing  Extreme weakness  Disorientation or coma  Unavailability of water from vomiting, diarrhea, hemorrhage, diaphoresis, excessive wound drainage, or diuretic therapy  Deficit Fluid Volume: Signs and Symptoms  Thirst, poor skin turgor; dry lips, tongue, mucous membranes, and skin; sunken, soft eyeballs  Weakness, dizziness, postural hypotension  Weight loss  Decreased urine production; dark, concentrated urine with high specific gravity  Thick saliva  Elevated temperature ≥100.6° F (38.1° C)  Rapid, weak, thready pulse  Increased hematocrit  Deficit Fluid Volume: Nursing Management  Increase fluid intake or decrease fluid loss (or both).  Nursing consideration  Assigning unlicensed assistive personnel to encourage fluid intake  Nausea and Vomiting: Pathophysiology  A feeling of discomfort or an unpleasant sensation vaguely felt in the epigastrium and abdomen.  Nausea is experienced when nerve endings in the stomach and other parts of the body are irritated.  Irritated nerve endings in the stomach send messages to the part of the brain that controls the vomiting reflex  Nausea and vomiting are automatic responses of the involuntary autonomic nervous system to unpleasant stimuli.  Nausea and Vomiting: Treatment  Complementary and alternative therapies  Sea Bands (acupressure wrist bands)  Ginger tea  Pharmacologic measures  Antihistamines  Sedatives and hypnotics  Anticholinergics  Phenothiazines  Nausea and Vomiting: Nursing Management  Have the patient lie down and turn his or her head to one side Hold an emesis basin close to the side of the face.  Use a cool, damp washcloth to wipe the patient’s face and the back of the neck.  Have the patient breathe through the mouth.  Provide mouth care after the episode.  Sucking on ice chips may help reduce nausea.  A quiet, cool, odor-free environment.  Observe for dehydration.  Diarrhea: Pathophysiology  Local irritation of the intestinal mucosa, especially by infectious agents and chemicals  Chronic and prolonged diarrhea typical of ulcerative colitis, irritable bowel syndrome, allergies, lactose intolerance, and nontropical sprue  Obstruction to flow of intestinal contents also can produce diarrhea.  Diarrhea causes considerable potassium and sodium loss.  Diarrhea: Nursing Management  Limit the intake of foods to rest the bowels.  When oral feedings are allowed, begin clear liquids, progress to bland liquids, and then provide solid foods of increased calories and high-protein, high-carbohydrate content.  Give rehydrating solutions containing glucose and electrolytes first.  Avoid iced fluids, carbonated drinks, whole milk, roughage, raw fruits, and highly seasoned foods.  Diarrhea: Treatment  Medications  Mild cases are treated with kaolin and bismuth preparations, (e.g., Kaopectate).  Diarrhea caused by infections may be treated with drugs specific for the causative organism. It is sometimes advisable to allow the organism or toxin to be eliminated naturally from the body, so drugs may not be given initially.  If metabolic acidosis occurs, treat by giving buffer solutions.  Excess Fluid Volume  Water intoxication related to IV therapy, enema, and so on  Impaired elimination, such as occurs in renal failure  Hypervolemia elevates blood pressure  Edema is associated with retention of water  Hematocrit will be below the normal values because of dilution by the water  Electrolytes  Molecules in solution  Anions and cations  Electrolytes create electrical impulses used in nerve conduction, contraction of muscles, and excretion of hormones and other substances from glandular cells.  Electrolyte Imbalances  Electrolytes have many functions in the body.  Imbalances are too much or too little of an electrolyte circulating in the bloodstream or inside the cells of the body.  Audience Response Question 1 Which patient(s) would be considered at high risk for fluid and electrolyte imbalance? (Select all that apply.) 1. A 45-year-old woman with thyroid crisis 2. A 35-year-old trauma victim on a ventilator 3. A 60-year-old woman with temperature of 98.6° F 4. A 70-year-old man on anticoagulant therapy 5. A 30-year-old woman complaining of persistent diarrhea  Hyponatremia  Sodium level less than 135 mEq/L  Pathophysiology  Occurs from either sodium loss, inadequate intake of sodium or excess of water.  Signs and symptoms  Central nervous system and neuromuscular changes  Nursing interventions  Restrict water intake  Closely monitor patient IV solutions  Replace water loss with fluids containing sodium  Hypernatremia  Sodium level more than 145 mEq/L  Pathophysiology  Osmotic shift of fluid from the cells to the interstitial spaces  Water loss from fever, respiratory infection, or diarrhea  Signs and symptoms  Dry mucous membranes, loss of skin turgor, intense thirst, flushed skin, oliguria, weakness  Nursing interventions  Increased fluid intake, measure intake and output, restrict sodium intake  Hypokalemia  Potassium level less than 3.5 mEq/L  Signs and symptoms  Abdominal pain, paralytic ileus, gaseous distention of intestine, cardiac dysrhythmias, muscle weakness, decreased reflexes, paralysis, urinary retention, lethargy, confusion  Nursing interventions  Teach about foods high in potassium  Teach patients to watch for signs of hypokalemia  Administer potassium chloride supplement  Monitor I&O and cardiac rhythm  Hyperkalemia  Potassium level more than 5.0 mEq/L  Pathophysiology  Disruption of cell membranes causes a shift of potassium from the ICF to the ECF  Signs and symptoms  Muscle weakness, fatigue, hypotension, nausea, paresthesias, paralysis, cardiac dysrhythmias  Nursing interventions  Decrease intake of foods high in potassium.  Increase fluid intake  Instruct patient in proper use of salt substitutes containing potassium.  Hypocalcemia (1 of 2)  Calcium level less than 8.4 mg/dL  Pathophysiology  Renal failure causes retention of phosphate ions, which causes a loss of calcium ions.  Removal or injury of the parathyroid glands  Conditions causing alkalosis  Signs and Symptoms  Paresthesias, abdominal cramps, weak pulse, decreased blood pressure, seizures, muscle spasms, tetany, positive Chvostek’s and Chvostek’s sign, cardiac dysrhythmia, wheezing, dyspnea, difficulty swallowing, colic, cardiac failure  Hypocalcemia (2 of 2)  Nursing Interventions  Encourage adults to consume sufficient calcium from cheese, broccoli, shrimp, and other dietary sources.  Have 10% calcium glaciate solution at the bedside of patients having thyroidectomy in case of surgical damage to the parathyroid glands.  Give all oral medicines containing calcium 30 minutes before meals to facilitate absorption.  Hypercalcemia  Calcium level more than 10.6 mg/dL  Pathophysiology  Lengthy immobilization, when calcium is mobilized from the bone  An excess of calcium or vitamin D is taken into the body.  Signs and symptoms  Anorexia, nausea, abdominal pain, constipation, muscle weakness, oliguria, confusion, renal calculi, pathologic fractures, dysrhythmias, cardiac arrest  Nursing interventions  Diuretics to increase urinary output and calcium excretion.  Monitor I&O.  Encourage high fluid intake (3000 to 4000 mL/day).  Hypomagnesemia  Magnesium levels less than 1.3 mEq/L  Pathophysiology  Usually due to hypokalemia and hypocalcemia  Signs and symptoms  Insomnia, hyperactive reflexes, leg and foot cramps, twitching, tremors, seizures, cardiac dysrhythmias, positive Chvostek’s and Trousseau’s sign, vertigo, hypocalcemia, hypokalemia  Nursing interventions  Increase magnesium in diet  Monitor IV infusions of magnesium closely  Monitor I&O  Hypermagnesemia  Magnesium levels more than 2.1 mEq/L  Pathophysiology  Rare, but may occur with renal failure or from overuse of magnesium-containing antacids and cathartics  Signs and symptoms  Hypotension, sweating and flushing, nausea and vomiting, muscle weakness, paralysis, respiratory depression, cardiac dysrhythmias  Nursing interventions  Teach patient to avoid use of antacids and laxatives.  Encourage fluid intake  Anion Imbalances  Hypochloremia  Hyperchloremia  Hypophosphatemia  Hyperphosphatemia  Hypophosphatemia  Phosphate level less than 3.0 mg/dL  Signs and symptoms  Confusion, seizures, numbness, weakness, possible coma  Chronic state may cause rickets and osteomalacia  Risk factors  Vitamin D deficiency or hyperparathyroidism  Use of aluminum-containing antacids  Nursing interventions  Assess for vitamin D deficiency, hyperparathyroidism, and overuse of aluminum-containing antacids.  Hyperphosphatemia  Phosphate level more than 4.5 mg/dL  Signs and symptoms  Anorexia, nausea, vomiting  Risk factors  Renal insufficiency  Nursing interventions  Assess for restlessness, confusion, chest pain, and cyanosis  Monitor respirations  Check all electrolyte levels  Acid-Base System  An acid is capable of giving up a hydrogen ion.  A base is capable of accepting a hydrogen ion.  Salt and neutralization  Acids react with bases to form water and salt— neutralization reaction  Carbonic acid = Bicarbonate + Hydrogen = Carbon dioxide + Water  Acid-Base System: pH  pH is the concentration of hydrogen (H+) in a solution.  A chemically neutral solution has a pH of 7.00.  Normal body pH is 7.35 to 7.45. Below 7.25 or above 7.55 is considered life threatening. Above 7.8 (alkalosis) or below 6.8 (acidosis) usually is fatal. 7.4 indicates a ratio of 1 part carbonic acid to 20 parts bicarbonate (base).  Acidosis and Alkalosis  Acidosis  The result of either a loss of base or an accumulation of acid  Alkalosis  The result of either a loss of acid or an accumulation of base  Three Mechanisms That Balance pH  Buffer systems  Respiratory system  Renal system  Buffer Systems  The bicarbonate–carbonic acid buffer system is responsible for more than half of the buffering.  Three other buffer systems in the body include:  Phosphate  Hemoglobin  Protein  Respiratory System  Because carbon dioxide dissolves in the blood and combines with water to form carbonic acid, retaining or blowing off carbon dioxide helps retain or eliminate acids from the body.  The respiratory system alters breathing rate and depth.  Renal System  The renal system changes the excretion rate of acids and the production and absorption of bicarbonate ion.  The kidneys are slow to compensate but are the most effective compensating mechanism.  Acid-Base Imbalances  Respiratory acidosis  Metabolic acidosis  Respiratory alkalosis  Metabolic alkalosis  Respiratory Acidosis  Blood gas values  pH < 7.35  Paco2 > 45 mm Hg  Causes  Acute problems, such as airway obstruction, pneumonia, asthma, chest injuries, or pulmonary edema  Chronic obstructive pulmonary disease (COPD), such as emphysema  Opiate use that depresses the respiratory rate  Metabolic Acidosis  Blood gas values  pH < 7.35  HCO3− < 22 mEq/L  Causes  Excessive loss of bicarbonate ions from diarrhea  Renal failure  Diabetic ketoacidosis (DKA)  Hyperkalemia  Sepsis  Respiratory Alkalosis  Blood gas values  pH > 7.45  Paco2 < 35 mm Hg  Cause  Anxiety  High fever  An overdose of aspirin  Metabolic Alkalosis  Blood gas values  pH > 7.45  HCO3− > 26 mEq/L  Causes  Vomiting  Extensive gastrointestinal suction  Hypokalemia  Excessive use of antacids with bicarbonate  Arterial Blood Gas Analysis  Pao2  Paco2  pH  Sao2  HCO3−  Pao2  Partial pressure (P) exerted by oxygen (O2) in the arterial blood (a)  Normal value is 80 to 100 mm Hg.  Indicates the amount of oxygen carried in the blood  Paco2  Partial pressure (P) of carbon dioxide (CO2) in the arterial blood (a)  Normal value is 35 to 45 mm Hg.  Indicates the amount of carbon dioxide in the blood  pH  An expression of the extent to which the blood is alkaline or acid  Normal value is 7.35 to 7.45.  Sao2  Also abbreviated O2 Sat  Percentage of available hemoglobin that is saturated (Sa) with oxygen (O2)  For instance, the ratio of the amount of oxygen that is combined with hemoglobin to the total amount of oxygen the hemoglobin can carry  Normal value is 94% to 100%.  HCO3−  The level of plasma bicarbonate  An indicator of the metabolic acid-base status  Normal value is 22 to 26 mEq/L.  Base Excess or Deficit  Indicates the amount of blood buffer present  Alkalosis is present when this value is abnormally high.  Acidosis is present when this value is abnormally low. Acid-Base Imbalances Home Care Considerations  Fluid intake and restriction  Sodium restriction  Manage underlying cause  Monitor tests  Intravenous Fluid Therapy  Maintenance fluids  Oral and parenteral replacement  Parenteral nutrition  Blood and blood products  Plasma expanders  Nursing Responsibilities  Administering IV fluids  The goals of nursing care for a patient receiving an IV infusion are to:  Prevent infection.  Minimize physical injury to the veins and surrounding tissues.  Administer the correct fluid at the prescribed time and at a safe rate of flow.  Observe the patient’s reaction to the fluid and medications being administered.  Rights of IV Therapy  Right solution with or without additives as ordered; the correct solution to follow what has been infusing  Right dose (amount) of solution and additive as ordered  Right route (peripheral IV, peripherally inserted central catheter [PICC], central line, port)  Right time (to infuse)  Right patient as identified with two identifiers  Right documentation  Calculating and Regulating the Rate of Flow  Monitor infusions  When possible use an IV pump  Principles affecting flow rates  IV Therapy  Intravenous intake  Flushing as-needed locks or central lines  Flushing intravenous catheters  Providing central line care  Blood drawing  Partial or total parenteral nutrition  Applicable Nursing Diagnoses  Deficient fluid volume  Excess fluid volume  Risk for imbalanced fluid volume  Ineffective tissue perfusion  Decreased cardiac output  Impaired gas exchange  Ineffective breathing pattern  Risk for injury related to IV fluid administration  Community Care  Frequent monitoring  Medication safety  Patient teaching  Collaborative approach