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FLUIDS, ELECTROLYTES, ACID-BASE BALANCE, AND INTRAVENOUS THERAPY 1 Theory Objectives Recall the various functions fluid performs in the body. Identify the body’s mechanisms for fluid regulation. Review three ways in which body fluids are continually being distributed among the body’s fluid compartments. Distinguish the signs and symptoms of various electrolyte imbalances. Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 2 Theory Objectives (cont.) Discuss why the elderly have more problems with fluid and electrolyte imbalances. Recognize the disorders that cause specific fluid and electrolyte imbalances. Compare the major causes of acid-base imbalances. State interventions to correct an acid-base imbalance. Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 3 Theory Objectives (cont.) Discuss the steps in managing an intravenous infusion. Describe the measures used to prevent the complications of intravenous therapy. Identify intravenous fluids that are isotonic. Discuss the principles of intravenous therapy. Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 4 Clinical Practice Objectives 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. Carry out interventions to correct an electrolyte imbalance. Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. Clinical Practice Objectives (cont.) Determine if a patient has an acid-base imbalance. Carry out measures to prevent the complications of intravenous therapy. Compare interventions for the care of a patient receiving total parenteral nutrition with one undergoing intravenous therapy. Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 5 6 Functions of Water Transportation Heat regulation Maintenance of hydrogen (H+) balance Medium for the enzymatic action of digestion Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 7 Control of Fluid Balance Thirst mechanism and osmoreceptors Antidiuretic hormone (ADH) Aldosterone and atrial natriuretic peptide (ANP) Baroreceptors in the carotid sinus and aortic arch and the sympathetic/parasympathetic nervous system Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. Movement of Fluid and Electrolytes Passive transport Diffusion Osmosis Filtration Active transport Living cells in solutions Isotonic Hypertonic Hypotonic Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 8 Movement of Fluid and Electrolytes (cont.) 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 semi-permeable membrane Filtration is the movement of water and solutes through a semi-permeable membrane due to a pushing force (hydrostatic pressure) on one side of the membrane Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 9 Movement of Fluid and Electrolytes (cont.) Active transport Requires cellular energy Moves molecules into cells against electrical and/or concentration gradients Uses energy (ATP)–requiring pump Example: sodium-potassium pump Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 10 11 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 12 Signs and Symptoms Thirst Poor skin turgor; dry lips, tongue, mucous membranes, and skin; and sunken, soft eyeballs Weakness, dizziness, postural hypotension Weight loss Decreased urine production; dark, concentrated urine with high specific gravity Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 13 Signs and Symptoms (cont.) Thick saliva Elevated temperature ≥100.6° F (38.1° C) Flat neck veins when lying down Rapid, weak, thready pulse Increased hematocrit Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 14 Nursing Management Increase fluid intake and/or decrease fluid loss Nursing considerations Assigning unlicensed assistive personnel to encourage fluid intake Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. Nursing Management of Nausea and Vomiting Pathophysiology and assessment Complementary and alternative therapies Sea bands (acupressure wrist bands) Ginger tea Pharmacologic measures Antihistamines Sedatives and hypnotics Anticholinergics Phenothiazines Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 15 Nursing Management of Nausea and Vomiting (cont.) Have the patient lie down and turn his head to one side, or have the patient sit and lower his head between the legs so that vomitus is not aspirated into the respiratory tract 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 16 Nursing Management of Nausea and Vomiting (cont.) Have the patient breathe through the mouth Provide mouth care after the episode Sucking on ice chips helps reduce nausea in some patients A quiet, cool, odor-free environment helps calm nausea If nausea and vomiting persist, observe for dehydration Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 17 18 Elder Care Considerations Cautious rehydration Patients with cardiac problems are at risk for fluid overload from intravenous (IV) infusions Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. Nursing Management of Diarrhea 19 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. Nursing Management of Diarrhea (cont.) 20 Nursing measures Limit the intake of foods to rest the bowels Once oral feedings are allowed, begin clear liquids, progress to bland liquids, then solid foods of increased calories and high-protein, highcarbohydrate content Give rehydrating solutions containing glucose and electrolytes first Avoid iced fluids, carbonated drinks, whole milk, roughage, raw fruits, and highly seasoned foods Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 21 Medications for Diarrhea Mild cases 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/toxin to be eliminated naturally from the body, and so drugs may not be given initially If metabolic acidosis occurs, treat by giving buffer solutions Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 22 Excess Fluid Volume Pathophysiology Water intoxication related to IV therapy, enema, etc. Impaired elimination, such as occurs in renal failure Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 23 Hematocrit Objective measure of water excess Measures the percentage of red blood cells in a volume of whole blood. Normal: 35 to 54 mL of red blood cells per 100 mL of whole blood depending on age and sex If there is an excess of water, the proportion of red blood cells to milliliters of blood will be lower, and the hematocrit will be below the normal values because of dilution by the water Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 24 Urine Specific Gravity Normal range: 1.003–1.030 Average range: 1.010–1.025 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 25 Edema Pathophysiology Edema is accumulation of freely moving interstitial fluid associated with the retention of water, sodium, and chloride It can occur in body cavities, as in the peritoneal cavity (ascites) and the cranial cavity Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 26 Causes of Edema Four general causes of edema are Loss of plasma proteins Obstruction of lymphatic circulation An increase in capillary permeability An increase in capillary hydrostatic pressure Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 27 Pitting Edema Scale 1+ Mild pitting 2+ Moderate pitting 3+ Deep pitting 4+ Very deep pitting Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 28 Generalized Edema Occurs when the body’s mechanisms for eliminating excess sodium fail Becomes life-threatening when accumulated fluids overload the circulatory system, as in congestive heart failure, and when fluids accumulate in the lungs, as in pulmonary edema Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 29 Lymphedema Associated with lymph node removal Inflammatory response, infection, and chemical mediators Third spacing Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 30 Localized Edema Usually is non-pitting, does not come and go, and is characterized by tight, shiny skin that is stretched over a hard and red area Causes of localized edema Trauma Allergies Burns Obstruction of lymph flow Liver failure Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 31 Dependent Edema An effect of gravity Can be somewhat relieved by elevating the affected body part 18 inches (or above heart level, when possible) and by repositioning the patient frequently Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 32 Treatment of Edema Correct underlying cause Assist to rebalance fluid content Fluid may be restricted or diuretic drugs may be administered to facilitate excretion of the excess fluid Bed rest may be ordered to facilitate fluid excretion as the kidneys function best when the body is supine Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 33 Treatment of Edema (cont.) Low-sodium diet Elastic stockings or sequential compression devices Intake and output recording Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. Volume Disturbances Home Care Considerations Fluid deficit Patient teaching Small fluid intake Persistent symptoms Fluid excess Weigh daily Persistent weight gain and physician consult Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 34 35 Osmolality Concentration of the solution determined by the number of solutes Solutes can be nonelectrolyte (protein, urea, glucose, creatinine, and bilirubin) or electrolyte (sodium, chloride, potassium, etc.) Normal: 280–294 mOsm/kg Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 36 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 37 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 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 Correct Answer: 1, 2, and 5 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 38 Electrolyte Imbalances Hyponatremia Hypomagnesemia Hypernatremia Hypermagnesemia Hypokalemia Hypophosphatemia Hyperkalemia Hyperphosphatemia Hypocalcemia Hypercalcemia Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 39 Hyponatremia Na+ less than 135 mEq/L The average intake of sodium is 4 to 5 g/day If there is a problem with water balance, sodium may be restricted in the diet The consequence of hyponatremia is impaired nerve conduction Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 40 Pathophysiology Hyponatremia can occur from either a sodium loss or an excess of water Decreased secretion of aldosterone Congestive heart failure, liver disease with ascites, and chronic renal failure result in excessive water retention—without concurrent sodium retention— which results in hypervolemia combined with hyponatremia Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 41 Signs and Symptoms CNS and neuromuscular changes resulting from failure of swollen cells to transmit electrical impulses Fatigue, lethargy, headache, mental confusion, altered level of consciousness, anxiety, coma, anorexia, nausea, vomiting, muscle cramps, seizures, decreased sensation, and decreased B/P Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 42 Risk Factors Inadequate sodium intake, as in patients on lowsodium diets Excessive intake or retention of water (kidney failure and heart failure) Loss of bile (which is rich in sodium) as a result of fistulas, drainage, gastrointestinal surgery, nausea and vomiting, and suction Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 43 Risk Factors (cont.) Loss of sodium through burn wounds Administration of intravenous (IV) fluids that do not contain electrolytes Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 44 Nursing Interventions Restrict water intake as ordered for patients with congestive heart failure, kidney failure, and inadequate antidiuretic hormone production Liberalize diet of patient on low-sodium diet Closely monitor patient receiving IV solutions to correct hyponatremia Replace water loss with fluids containing sodium Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 45 Hypernatremia Na+ more than 145 mEq/L Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 46 Assessment Good tissue turgor and firm subcutaneous tissues occur during hypernatremia Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 47 Pathophysiology Hypernatremia causes an osmotic shift of fluid from the cells to the interstitial spaces, which causes a cellular dehydration and interruption of normal cell processes Water loss from fever, respiratory infection, or watery diarrhea is the usual cause Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 48 Pathophysiology (cont.) The body tries to correct the situation by conserving water through reabsorption in the renal tubules Excessive administration of sodium bicarbonate for the treatment of acidosis Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 49 Signs and Symptoms Dry mucous membranes Loss of skin turgor Intense thirst Flushed skin Oliguria Possibly elevated temperature Weakness Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 50 Signs and Symptoms (cont.) Lethargy Irritability Twitching Seizures Coma Intracranial bleeding Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 51 Risk Factors High-sodium diet, inadequate water intake as in comatose, mentally confused, or debilitated patients Excessive sweating, diarrhea, failure of kidney to reabsorb water from urine Administration of high-protein, hyperosmotic tube feedings and osmotic diuretics Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 52 Nursing Interventions Encourage increased fluid intake Measure intake and output (I&O) Give water between tube feedings Restrict sodium intake Monitor temperature Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 53 Hypokalemia K+ < 3.5 mEq/L Severe hypokalemia (K+ less than 2.5 mEq/L) may cause cardiac arrest Extra potassium must be given to help correct an imbalance Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 54 Signs and Symptoms Abdominal pain Paralysis Paralytic ileus Urinary retention Gaseous distention of intestines Increased urinary pH Lethargy Confusion Electrocardiogram (ECG) changes Cardiac dysrhythmias Muscle weakness Decreased reflexes Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 55 Risk Factors Inadequate intake of potassium-rich foods Loss of potassium in urine when kidneys do not reabsorb the mineral Loss of potassium from intestinal tract as a result of diarrhea or vomiting, drainage from fistulas, overuse of gastric suction Improper use of diuretics Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 56 Nursing Interventions Instruct patients (especially those taking diuretics) about foods high in potassium content; encourage intake Observe closely for signs of digitalis toxicity in patients taking this drug Teach patients to watch for signs of hypokalemia Administer potassium chloride supplement as ordered Monitor I&O and cardiac rhythm Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 57 Hyperkalemia K+ > 5.0 mEq/L Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 58 Pathophysiology Disruption of cell membranes causes a shift of potassium from the ICF to the ECF in extensive tissue damage occurs from burns or crush injuries Hyperkalemia can cause life-threatening cardiac dysrhythmias Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 59 Signs and Symptoms Muscle weakness Fatigue Hypotension Nausea Paresthesias Paralysis Cardiac dysrhythmias ECG changes Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 60 Risk Factors Kidney failure, decreased kidney function Intestinal obstruction that prevents elimination of potassium in the feces Addison’s disease, digitalis toxicity, uncontrolled diabetes mellitus, insulin deficit, crushing injuries and burns Overuse of potassium-containing salt substitute or overuse of potassium-sparing diuretic Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 61 Nursing Interventions Decrease intake of foods high in potassium Increase fluid intake to enhance urinary excretion of potassium; provide adequate carbohydrate intake to prevent use of body proteins for energy Carefully administer proper dose of insulin to diabetic patients Instruct patient in proper use of salt substitutes containing potassium Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 62 Hypocalcemia < 8.4 mg/dL Calcium ions are needed for enzyme reactions including blood clotting, nerve conduction, and muscle contraction Carpopedal spasm (also called Trousseau’s sign), hyperactive reflexes, Chvostek’s sign, and tetany Laryngospasm may occur if deficit is severe Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 63 Pathophysiology Hypocalcemia in renal failure results from retention of phosphate ions, which causes a loss of calcium ions In addition, during renal failure, vitamin D is not activated, causing the loss of absorption of calcium from the intestinal tract Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 64 Pathophysiology (cont.) Removal or injury of the parathyroid glands during thyroidectomy causes parathyroid hormone deficiency and consequent hypocalcemia Conditions causing alkalosis may cause hypocalcemia Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 65 Signs and Symptoms Paresthesias Abdominal cramps Weak pulse Decreased BP Seizures Muscle spasms Tetany Hand spasm Positive Chvostek’s sign Positive Trousseau’s sign Cardiac dysrhythmia Wheezing Dyspnea Difficulty swallowing Colic Cardiac failure Excessive blood transfusions Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 66 Risk Factors Metastatic cancer, inadequate dietary intake of calcium and vitamin D Impaired absorption of calcium from intestinal tract, as in diarrhea, sprue, overuse of laxatives and enemas containing phosphates (phosphorus tends to be more readily absorbed from the intestinal tract than calcium and suppresses calcium retention in the body) Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 67 Risk Factors (cont.) The parathyroid regulates calcium and phosphorus levels Hyposecretion of parathyroid hormone can result in hypocalcemia Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 68 Nursing Interventions Encourage adults to consume sufficient calcium from cheese, broccoli, shrimp, and other dietary sources Have 10% calcium glaciate solution at bedside of patient having thyroidectomy in case of surgical damage to the parathyroid glands Give all oral medicines containing calcium 30 minutes before meals to facilitate absorption Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 69 Hypercalcemia > 10.6 mg/dL Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 70 Pathophysiology Hypercalcemia occurs when the serum calcium level is above 10.6 mg/dL Lengthy immobilization, when calcium is mobilized from the bone An excess of calcium or vitamin D is taken into the body Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 71 Signs and Symptoms Anorexia Confusion Nausea Renal calculi Abdominal pain Pathologic fractures Constipation Dysrhythmias Muscle weakness Cardiac arrest Oliguria Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 72 Risk Factors Excess intake of calcium, as in patient taking antacids indiscriminately Excess intake of vitamin D Conditions that cause movement of calcium out of bones and into extracellular fluid (e.g., bone tumor, multiple fractures) Tumors of the lung, stomach, and kidney, and multiple myeloma Immobility and osteoporosis Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 73 Nursing Interventions Administer diuretics as prescribed to increase urinary output and calcium excretion Monitor I&O Encourage high fluid intake (3000–4000 mL/day) Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 74 Hypomagnesemia < 1.3 mEq/L Magnesium is important in DNA and protein synthesis, and in many enzyme reactions Magnesium imbalances are rare, but can be caused by a variety of factors Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 75 Pathophysiology Hypomagnesemia occurs when the serum level drops below 1.3 mEq/L It usually is present when hypokalemia and hypocalcemia occur Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 76 Signs and Symptoms Insomnia Positive Chvostek’s sign Hyperactive reflexes Positive Trousseau’s sign Leg and foot cramps Vertigo Twitching Hypocalcemia Tremors Hypokalemia Seizures Cardiac dysrhythmias Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 77 Risk Factors Chronic malnutrition, chronic diarrhea Bowel resection with ileostomy or colostomy Chronic alcoholism Thiazide diuretic use Prolonged gastric suction Acute pancreatitis Biliary or intestinal fistula Osmotic diuretic therapy Diabetic ketoacidosis Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 78 Nursing Interventions Diet counseling to help patients at risk increase their level of magnesium (e.g., milk and cereals) Monitor intravenous infusions of magnesium closely Monitor I&O Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 79 Hypermagnesemia > 2.1 mEq/L Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 80 Pathophysiology Hypermagnesemia is present when there is a serum level above 2.1 mEq/L Occurs rarely, in the presence of renal failure or from overuse of magnesium-containing antacids and cathartics Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 81 Signs and Symptoms Hypotension Sweating and flushing Nausea and vomiting Muscle weakness Paralysis Respiratory depression Cardiac dysrhythmias Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 82 Risk Factors Overuse of antacids and cathartics containing magnesium Aspiration of seawater, as in near-drowning Chronic kidney failure Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 83 Nursing Interventions Teach patients to avoid abuse of laxatives and antacids; instruct patients with renal problems to avoid over-the-counter drugs that contain magnesium Encourage fluid intake to increase urinary excretion of magnesium if not contraindicated Monitor I&O Administer diuretics as ordered Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 84 Anion Imbalances Hypochloremia Hyperchloremia Hypophosphatemia Hyperphosphatemia Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 85 Hypophosphatemia < 3.0 mg/dL Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 86 Signs and Symptoms Confusion Seizures Numbness Weakness Possible coma Chronic state may cause rickets and osteomalacia Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 87 Risk Factors Vitamin D deficiency or hyperparathyroidism Use of aluminum-containing antacids Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 88 Nursing Interventions Assess for vitamin D deficiency, hyperparathyroidism, or overuse of aluminumcontaining antacids Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 89 Hyperphosphatemia > 4.5 mg/dL Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 90 Signs and Symptoms Anorexia Nausea Vomiting Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 91 Risk Factors Renal insufficiency Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 92 Nursing Interventions Assess for restlessness, confusion, chest pain, and cyanosis Monitor respirations Check all electrolyte levels Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 93 Acid-Base Balance 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 94 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 7.35–7.45 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) Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 95 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. Three Mechanisms That Balance pH Buffer systems Respiratory system Renal system Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 96 97 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 98 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 Respiratory system alters breathing rate and depth Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 99 Renal System 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 100 Acid-Base Imbalances Respiratory acidosis Metabolic acidosis Respiratory alkalosis Metabolic alkalosis Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 101 Respiratory Acidosis Blood gas values pH < 7.35 PaCO2 > 45 mm Hg Causes Slow, shallow respirations Respiratory congestion/obstruction Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 102 Metabolic Acidosis Blood gas values pH < 7.35 HCO3 < 22 mEq/L Causes Shock (poor circulation) Diabetic ketoacidosis Renal failure Diarrhea Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 103 Respiratory Alkalosis Blood gas values pH > 7.45 PaCO2 < 35 mm Hg Cause Hyperventilation Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 104 Metabolic Alkalosis Blood gas values pH > 7.45 HCO3 > 26 mEq/L Causes Vomiting Excessive antacid intake Hypokalemia Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 105 Arterial Blood Gas Analysis PaO2 PaCO2 pH SaO2 HCO3– Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 106 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 107 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 108 pH An expression of the extent to which the blood is alkaline or acid Normal value is 7.35 to 7.45 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 109 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% Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 110 HCO3– The level of plasma bicarbonate An indicator of the metabolic acid-base status Normal value is 22 to 26 mEq/L Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 111 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 112 Respiratory Acidosis pH PaCO2 < 7.35 > Greater than 45 mm Hg HCO3– Normal 22–26 mEq/L Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 113 Causes Airway obstruction, pneumonia, asthma, chest injuries, or pulmonary edema Chronic obstructive pulmonary disease such as emphysema With opiate use that depresses the respiratory rate Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 114 Signs and Symptoms Increasing difficulty breathing History of respiratory obstruction (acute or chronic) Dyspnea Weakness Dizziness Restlessness Sleepiness Change in mental alertness Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 115 Management Establishment or maintenance of an airway Tracheostomy Endotracheal tube Oxygen administration Mechanical ventilator Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 116 Conservative Treatment Postural drainage, deep-breathing exercises, bronchodilators, and antibiotics if indicated Caution with narcotics, hypnotics, and tranquilizers Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 117 Metabolic Acidosis pH PaCO2 Less than 7.35 Normal 35–45 mm Hg HCO3– Less than 22 mEq/L Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 118 Causes Excessive loss of bicarbonate ions from diarrhea Renal failure Diabetic ketoacidosis Hyperkalemia Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 119 Signs and Symptoms Weakness Lethargy Headache Confusion These symptoms progress to stupor, unconsciousness, coma, and death Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 120 Ketoacidosis Vomiting and diarrhea Deep rapid breathing (Kussmaul’s respirations) May secrete urine with a low pH Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 121 Treatment Underlying cause Insulin and diabetic ketoacidosis Dialysis Intravenous (IV) bicarbonate or lactate Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 122 Respiratory Alkalosis pH PaCO2 > 7.45 < than 35 mm Hg HCO3– Normal 22–26 mEq/L Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 123 Causes Hyperventilation (a rapid respiratory rate) results in respiratory alkalosis It is usually caused by anxiety, high fever, and overdose of aspirin Hyperventilation can be caused by hypoxemia, reactions to certain drugs, pain, and panic Overzealous use of mechanical ventilation also can cause hyperventilation Head injuries may also lead to hyperventilation Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 124 Signs and Symptoms Deep, rapid breathing Tingling of the fingers Pallor around the mouth Dizziness Spasms of the muscles of the hands Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 125 Treatment Address the underlying disorder Prevent further hyperventilation and help the patient re-establish a normal level of carbon dioxide in the blood Sedatives may be given to calm the patient Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 126 Treatment (cont.) To aid in the retention of carbon dioxide, the patient may be instructed to hold the breath, or to breathe into a paper sack and re-breathe the carbon dioxide just exhaled This recycling of carbon dioxide can eventually restore normal carbonic acid levels in the blood Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 127 Metabolic Alkalosis pH PaCO2 Greater than 7.45 Normal 35–45 mm Hg HCO3– Greater than 26 mEq/L Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 128 Causes Vomiting Extensive gastrointestinal suction Hypokalemia Excessive consumption of antacids with bicarbonate Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 129 Signs and Symptoms Neurologic signs: Respiratory manifestations: Irritability, disorientation, lethargy, muscle twitching, tingling and numbness of the fingers, convulsions Slow, shallow respirations, decreased chest movements, cyanosis There may be symptoms of potassium and calcium depletion Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 130 Signs and Symptoms (cont.) If the alkalosis progresses, tetany, seizures, and coma Tetany is characterized by severe muscle cramps, carpopedal spasms, laryngeal spasms, and stridor (shrill, harsh sound upon inspiration) Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 131 Treatment Correct underlying cause Restore the body fluids to a less alkaline state Fluids and electrolytes replacement orally and parenterally as needed Emergency measures include the administration of an acidifying solution, such as ammonium chloride Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. Acid-Base Imbalances Home Care Considerations Fluid intake and restriction Sodium restriction Manage underlying cause Monitor tests Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 132 133 Intravenous Fluid Therapy Maintenance fluids Oral and parenteral replacement Parenteral nutrition Blood and blood products Plasma expanders Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 134 135 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 Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 136 Regulating the Rate of Flow Monitor infusions Principles affecting flow rates Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 137 Elder Care Points Frequent IV infusion monitoring “Catch-up” and risk for circulatory overload Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 138 IV Therapy Intake Flushing peripheral and central lines Facility policy and procedures Subcutaneous infusion Hypodermoclysis Epidural infusion Parenteral nutrition: TPN and PPN Patient-controlled analgesia Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 139 Applicable Nursing Diagnoses Deficient fluid volume Decreased cardiac output Excess fluid volume Impaired gas exchange Risk for imbalanced fluid volume Ineffective breathing pattern Ineffective tissue perfusion Risk for injury related to IV fluid administration Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 140 Planning Patient will exhibit normal skin turgor Patient’s weight will stabilize at normal baseline Intake and output will be balanced Blood gases will return to normal Breath sounds will be clear to auscultation There will be no evidence of edema Electrolyte values will be within normal limits Patient will not experience complications of IV therapy Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 141 Implementation Fluid and electrolytes Diuretics Daily weights Skin care Monitoring Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 142 Evaluation Every 24 hours Perform evaluations to see if nursing interventions are assisting the patient to meet expected outcomes If the patient is not progressing toward achievement of the outcomes, problem-solve and think critically to determine why, then alter the plan of care appropriately When a specific outcome is met, discontinue that portion of the plan Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc. 143 Community Care Frequent monitoring Medication safety Patient teaching Collaborative approach Elsevier items and derived items © 2013, 2009 by Saunders, an imprint of Elsevier Inc.
