Fluids and Electrolytes Part 1 Lecture PDF
Document Details
University of San Agustin
Philip Winston Yap, Fidel G. Yongque III, Geraldine Malayo
Tags
Summary
This document presents a lecture on fluids and electrolytes, covering topics such as the importance of water, variations in fluid content, fluid movements, and different types of fluid solutions (isotonic, hypotonic, hypertonic). It also touches upon how electrolytes are regulated and the processes involved.
Full Transcript
Prepared by: Philip Winston Yap, PhRN, USRN Fidel G. Yongque III, PhRN, USRN Geraldine Malayo, CNN, RN NCM 112: Care of Clients with Problems in Perioperative, Oxygenation, Cellular Aberration, Fluids and Electrolytes and Inflammatory and Immunologic Di...
Prepared by: Philip Winston Yap, PhRN, USRN Fidel G. Yongque III, PhRN, USRN Geraldine Malayo, CNN, RN NCM 112: Care of Clients with Problems in Perioperative, Oxygenation, Cellular Aberration, Fluids and Electrolytes and Inflammatory and Immunologic Disturbances. NCM 112 TERM TOPICS 1. Perioperative PRELIM 2. Fluids and Electrolytes 3. Shocks, Multiple Organ Dysfunction Syndrome MIDTERM 1. Immunologic and Inflammatory Disturbances 2. Cellular Aberration 3. Oxygenation- Respiratory FINALS 1. Oxygenation- Cardiovascular 2. Oxygenation- Hematologic 3. Relevant Legal, Moral and Ethical Standards of Care HOUSE RULES REFERENCE INTRODUCTION TO FLUIDS AND ELECTROLYTES HOW IMPORTANT IS WATER? Between 50% and 60% of the human body by weight is water Water provides a medium for transporting nutrients to cells and wastes from cells and for transporting substances such as hormones, enzymes, blood platelets, and red and white blood cells Water facilitates cellular metabolism and proper cellular chemical functioning Water acts as a solvent for electrolytes and nonelectrolytes Helps maintain normal body temperature Facilitates digestion and promotes elimination Acts as a tissue lubricant VARIATIONS IN FLUID CONTENT BODY FAT -Because fat cells contain little water and lean tissue is rich in water, the more obese the person, the smaller the percentage of total body water compared with body weight. -This is also true between sexes because females tend to have proportionally more body fat than males. - There is also an increase in fat cells in older people VARIATIONS IN FLUID CONTENT AGE AVENUES BY WHICH WATER ENTERS AND LEAVES THE BODY ANTIDIURETIC HORMONE REGULATION MECHANISMS ↑Osmolarity Osmoreceptors in hypothalamus Hypothalamus ↓Blood Volume receptor volume ↓ ↑ADH Kidney or ↓BP Atria and great veins tubules Posterior pituitary gland ↑H2O reabsorption Narcotics, Stress, Anesthetic agents, Heat, ↑vascular Nicotine, Antineoplastic volume and agents, Surgery ↓osmolarity RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM (RAAS) Juxtaglomerular RENIN Angiotensinogen in ↓Serum Sodium ↓Blood volume cells-kidney plasma Angiotensin I Angiotensin- converting Via vasoconstriction of arterial smooth muscle enzyme ↑Sodium Angiotensin II resorption (H2O resorbed Kidney tubules ALDOSTERONE with sodium); ↑ Adrenal Cortex Blood volume Intestine, sweat glands, Salivary glands Fluid Movements Fluids and solutes constantly move within the body, which allows the body to maintain homeostasis Fluids along with nutrients and waste products constantly shift within the body’s compartments from the cell to the interstitial spaces, to the blood vessels and back again Fluid Movements Types of Transport – A. Active transport – B. Passive transport Diffusion Osmosis Filtration Active Transport: Fluid Types Fluids in the body generally aren’t found in pure forms Isotonic, hypotonic, and hypertonic types Defined in terms of the amount of solute or dissolve substances in the solution Balancing these fluids involves the shifting of fluid not the solute involved Isotonic Solutions No net fluid shifts occur between isotonic solutions because the solution are equally concentrated Ex. NSS or 0.9SS Hypotonic Solutions Has a lower solute concentration than another solution Fluid from the hypotonic solution would shift into the second solution until the two solutions had equal concentrations Ex. Half normal or 0.45%SS Hypertonic Solutions Has a higher solute concentration than another solution Fluid from the second solution would shift into the hypertonic solution until the two solutions had equal concentrations Ex. D5NSS Fluid Replacement Therapy Administration routes – Oral route : oral ingestion of fluids and electrolytes as liquids or solids administered directly into the GI tract – Nasogastric route: instillation of fluids and electrolytes through feeding tubes, such as NG, gastrostomy and jejunostomy tubes – I.V. route: administration of fluids and electrolytes directly into the bloodstream using continuous infusion, bolus, or I.V. push injection through peripheral or central venous site Which among the following IV solutions contains the highest potassium content? A. D5 IMB B. Lactated Ringer's Solution C. D5 LRS D. D5 0.3 NaCl Composition of Different Intravenous Solution IVF Dextrose Na Cl K Lactate (g/L) (meq/L) (meq/L) (meq/L) (meq/L) D5 0.9% NaCl 50 154 154 D5 0.15% NaCl 50 25 25 D5 0.3% NaCl 50 51 51 D5 0.45% NaCl 50 77 77 D5 IMB 50 25 22 20 23 LRS 0 130 109 4 28 NSS 0 154 154 D5LRS 50 130 109 4 28 Fluid Replacement Therapy ISOTONIC SOLUTION Facts Examples Uses -same osmolality as plasma Dextrose 5% in -Fluid loss and (app. 275 to 295 mOsm/kg) water, dehydration -vascular space osmolality not -Hypernatremia altered by infusion -expand intracellular and Normal Saline -Blood transfusion, extracellular space equally; Solution, fluid challenges, degree of expansion correlates resuscitation, shock, with amount of fluid infused metabolic alkalosis, -no solution-related shifting hypercalcemia, between ICF and ECF spaces hyponatremia -cells neither shrink nor swell with fluid movement Lactated Ringers -Acute blood loss, Solution burns, dehydration, hypovolemia Fluid Replacement Therapy HYPOTONIC SOLUTION Fluid Replacement Therapy HYPERTONIC SOLUTION Assessment CLINICAL MEASUREMENT – Daily weights Each kg = 1 L of fluid To gain accuracy: – Balance the scale before each use and weigh the client; » At same time each day before breakfast after the first void » Wear the same or similar clothing » On the same scale – Vital signs Tachycardia – first sign of hypovolemia – Fluid I & O Oral fluids Ice chips Foods that tend to become fluid at room temperature Tube feedings Parenteral fluids IV meds Catheter or tube irrigant Urinary output – if with diaper, 1 g = 1 mL Vomitus or liquid feces Diaphoresis Tube drainage Wound dressing or wound fistula Laboratory Tests for Evaluating Fluid Status OSMOLALITY is the concentration of fluid that affects the movement of water between fluid compartments by osmosis. o It measures the solute concentration per kilo gram in blood and urine. o It is also a measure of a solution’s ability to create osmotic pressure and affect the movement of water. OSMOLALITY o Urine osmolality is determined by urea, creatinine, and uric acid. o It is reported as milliosmoles per kilogram of water (mOsm/kg) (Goertz, 2006). o In healthy adults, SERUM osmolality is 280 to 300 mOsm/kg, and normal URINE osmolality is 200 to 800 mOsm/kg (Goertz, 2006). OSMOLARITY, another term that describes the concentration of solutions, is measured in milliosmoles per liter (mOsm/L). URINE SPECIFIC GRAVITY measures the kidneys’ ability to excrete or conserve water. o The specific gravity of urine is compared to the weight of distilled water, which has a specific gravity of 1.000. o The normal range of urine specific gravity is 1.010 to 1.025. BUN is made up of urea, which is an end product of the metabolism of protein (from both muscle and dietary intake) by the liver. o Amino acid breakdown produces large amounts of ammonia molecules, which are absorbed into the blood stream. o Ammonia molecules are converted to urea and excreted in the urine. o The normal BUN is 10 to 20 mg/dL (3.6 to 7.2 mmol/L). CREATININE is the end product of muscle metabolism. o It is a better indicator of renal function than BUN because it does not vary with protein intake and metabolic state. o The normal serum creatinine is approximately 0.7 to 1.4 mg/dL (62 to 124 mmol/L); however, its concentration depends on lean body mass and varies from person to person. o Serum creatinine levels increase when renal function decreases HEMATOCRIT measures the volume percentage of red blood cells (erythrocytes) in whole blood and normally ranges from 42% to 52% for MALES and 35% to 47% for FEMALES. URINE SODIUM values change with sodium intake and the status of fluid volume: As sodium intake increases, excretion increases; as the circulating fluid volume decreases, sodium is conserved. o Normal urine sodium levels range from 75 to 200 mEq/24 hours (75 to 200 mmol/24 hours). Homeostatic Mechanisms KIDNEYS normally filter 180 L of plasma every day in the adult and excrete 1 to 2 L of urine. o They act both autonomously and in response to bloodborne messengers, such as aldosterone and antidiuretic hormone (ADH) (Porth & Matfin, 2009). o Regulation of pH of the ECF by retention of hydrogen ions o Excretion of metabolic wastes and toxic substances o The pumping action of the HEART circulates blood through the kidneys under sufficient pressure to allow for urine formation. HYPOVOLEMIA What is…? Fluid volume deficit (FVD), or hypovolemia, occurs when loss of ECF volume exceeds the intake of fluid. It occurs when water and electrolytes are lost in the same proportion as they exist in normal body fluids, so that the ratio of serum electrolytes to water remains the same. What is…? FVD (HYPOVOLEMIA) should not be confused with dehydration, which refers to loss of water alone, with increased serum sodium levels. FVD may occur alone or in combination with other imbalances. ETIOLOGY AND RISK FACTORS ETIOLOGY AND RISK FACTORS vomiting, diarrhea, GI suctioning, sweating; decreased intake, as in nausea or lack of access to fluids third-space fluid shifts, or the movement of fluid from the vascular system to other body spaces (eg, with edema formation in burns, ascites with liver dysfunction). Additional causes include diabetes insipidus, adrenal insufficiency, osmotic diuresis, hemorrhage, and coma. PATHOPHYSIOLOGY CLINICAL MANIFESTATIONS DIAGNOSTIC STUDIES the HEMATOCRIT LEVEL is greater than normal because there is a decreased plasma volume. 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 INCREASE Urine specific gravity Urine osmolality can be greater than 450 mOsm/kg, because the kidneys try to compensate by conserving water. MEDICAL MANAGEMENT If the deficit is not severe, the oral route is preferred, provided the patient can drink. However, if fluid losses are acute or severe, the IV route is required. Isotonic electrolyte solutions (eg, lactated Ringer’s solution, 0.9% sodium chloride) are frequently used to treat the hypotensive patient with FVD because they expand plasma volume. MEDICAL MANAGEMENT As soon as the patient becomes normotensive, a hypotonic electrolyte solution (eg, 0.45% sodium chloride) is often used to provide both electrolytes and water for renal excretion of metabolic wastes. The rate of fluid administration is based on the severity of loss and the patient’s hemodynamic response to volume replacement. MEDICAL MANAGEMENT If the patient with severe FVD is not excreting enough urine and is therefore oliguric, the primary health care provider needs to determine whether the depressed renal function is caused by reduced renal blood flow secondary to FVD (prerenal azotemia) or, more seriously, by acute tubular necrosis from prolonged FVD. The test used in this situation is referred to as a FLUID CHALLENGE TEST. MEDICAL MANAGEMENT During a fluid challenge test, volumes of fluid are administered at specific rates and intervals while the patient’s hemodynamic response to this treatment is monitored (ie, vital signs, breath sounds, sensorium, central venous pressure, urine output). An example of a typical fluid challenge involves administering 100 to 200 mL of normal saline solution over 15 minutes. MEDICAL MANAGEMENT The goal is to provide fluids rapidly enough to attain adequate tissue perfusion without compromising the cardiovascular system. The response by a patient with FVD but normal renal function is increased urine output and an increase in blood pressure and central venous pressure. NURSING MANAGEMENT The nurse monitors and measures fluid I&O at least every 8 hours, and sometimes hourly. Daily body weights are monitored; an acute loss of 0.5 kg (1 lb) represents a fluid loss of approximately 500 mL. (One liter of fluid weighs approximately 1 kg, or 2.2 lb.) The nurse observes for a weak, rapid pulse and orthostatic hypotension. A decrease in body temperature often accompanies FVD, unless there is a concurrent infection. Skin and tongue turgor are monitored on a regular basis. The degree of oral mucous membrane moisture is also assessed; a dry mouth may indicate either FVD or mouth breathing. NURSING MANAGEMENT Urine concentration is monitored by measuring the urine specific gravity. Mental function is eventually affected in severe FVD as a result of decreasing cerebral perfusion. Decreased peripheral perfusion can result in cold extremities. To prevent FVD, the nurse identifies patients at risk and takes measures to minimize fluid losses. If the patient is reluctant to drink because of oral discomfort, the nurse assists with frequent mouth care and provides nonirritating fluids. The patient may be offered small volumes of oral rehydration solutions (eg, Rehydralyte, Elete, Cytomax). If nausea is present, antiemetics may be needed before oral fluid replacement can be tolerated. If the deficit cannot be corrected by oral fluids, therapy may need to be initiated by an alternative route (enteral or parenteral) until adequate circulating blood volume and renal perfusion are achieved. Isotonic fluids are prescribed to increase ECF volume. HYPERVOLEMIA What is…? FLUID VOLUME EXCESS (FVE), or hypervolemia, refers to an isotonic expansion of the ECF caused by the abnormal retention of water and sodium in approximately the same proportions in which they normally exist in the ECF. It is always secondary to an increase in the total body sodium content, which, in turn, leads to an increase in total body water. ETIOLOGY AND RISK FACTORS Contributing factors can include heart failure, renal failure, and cirrhosis of the liver. Another contributing factor is consumption of excessive amounts of table or other sodium salts. Excessive administration of sodium-containing fluids in a patient with impaired regulatory mechanisms may predispose him or her to a serious FVE as well (Heitz & Horne, 2005). CLINICAL MANIFESTATIONS DIAGNOSTIC STUDIES MEDICAL MANAGEMENT Diuretics are prescribed when dietary restriction of sodium alone is insufficient to reduce edema by inhibiting the reabsorption of sodium and water by the kidneys. The choice of diuretic is based on the severity of the hypervolemic state, the degree of impairment of renal function, and the potency of the diuretic. MEDICAL MANAGEMENT THIAZIDE DIURETICS block sodium reabsorption in the distal tubule, where only 5% to 10% of filtered sodium is reabsorbed. Hydrochlorothiazide (HydroDIURIL) or metolazone (Mykrox, Zaroxolyn), are prescribed for mild to moderate hypervolemia. MEDICAL MANAGEMENT LOOP DIURETICS, such as furosemide (Lasix), bumetanide (Bumex), or torsemide (Demadex), can cause a greater loss of both sodium and water because they block sodium reabsorption in the ascending limb of the loop of Henle, where 20% to 30% of filtered sodium is normally reabsorbed. Loop diuretics are for severe hypervolemia. MEDICAL MANAGEMENT HEMODIALYSIS OR PERITONEAL DIALYSIS may be used to remove nitrogenous wastes and control potassium and acid–base balance, and to remove sodium and fluid. CONTINUOUS RENAL REPLACEMENT THERAPY may also be required. MEDICAL MANAGEMENT NUTRITIONAL THERAPY Strictly low sodium or no sodium diet. An average daily diet not restricted in sodium contains 6 to 15 g of salt, whereas low-sodium diets can range from a mild restriction to as little as 250 mg of sodium per day, depending on the patient’s needs. MEDICAL MANAGEMENT NUTRITIONAL THERAPY Seasoning substitutes can play a major role in decreasing sodium intake. Lemon juice, onions, and garlic are excellent substitute flavorings, although some patients prefer salt substitutes. Most salt substitutes contain potassium and must therefore be used cautiously by patients taking potassium- sparing diuretics. Salt substitutes containing ammonium chloride can be harmful to patients with liver damage. NURSING MANAGEMENT The nurse measures I&O at regular intervals to identify excessive fluid retention. The patient is weighed daily, and rapid weight gain is noted. An acute weight gain of 2.2 lb (1 kg) is equivalent to a gain of approximately 1 L of fluid. Breath sounds are assessed at regular intervals in at-risk patients, particularly if parenteral fluids are being administered. NURSING MANAGEMENT NURSING MANAGEMENT NURSING MANAGEMENT NURSING MANAGEMENT NURSING MANAGEMENT The nurse monitors the degree of edema in the most dependent parts of the body, such as the feet and ankles in ambulatory patients and the sacral region in patients confined to bed. NURSING MANAGEMENT Most patients require sodium-restricted diets in some form, and adherence to the prescribed diet is encouraged. Patients are instructed to avoid over-the- counter medications without first checking with a health care provider, because these substances may contain sodium. SODIUM AND FLUID RESTRICTION should be instituted as indicated. NURSING MANAGEMENT Regular rest periods may be beneficial, because bed rest favors diuresis of edema fluid = to diminished venous pooling and the subsequent increase in effective circulating blood volume and renal perfusion. If dyspnea or orthopnea is present, the patient is placed in a semi-Fowler’s position to promote lung expansion. The patient is turned and repositioned at regular intervals because edematous tissue is more prone to skin breakdown than normal tissue NURSING MANAGEMENT Edema can occur as a result of increased capillary fluid pressure, decreased capillary oncotic pressure, or increased interstitial oncotic pressure, causing expansion of the interstitial fluid compartment (Porth & Matfin, 2009). Edema can be localized (eg, in the ankle, as in rheumatoid arthritis) or generalized (as in cardiac and renal failure). Severe generalized edema is called ANASARCA. MANAGING ASCITES NURSING MANAGEMENT NURSING MANAGEMENT MANAGING ASCITES NURSING MANAGEMENT MANAGING ASCITES REFERENCES Hinkle, Janice L., Cheever, Kerry H. (2022). Bruner and Suddarth’s Textbook of Medical- Surgical Nursing, 15th Edition, Wulters Kluwer Black, Joyce M., Hawks, Jane, Hokanson (2008). Medical-Surgical Nursing Clinical Management for Patient Outcomes, 8th Edition, Elsevier (Singapore) Pte Ltd. Doenges, Marilynn E. et. al. (2016). Nurse’s Pocket Guide Diagnoses, Prioritized Interventions, and Rationales, 15th Edition, F.A. Davis Company. Taylor, Carol, Lynn, Pamela, Bartlett, Jennifer L. (2019). Fundamentals of Nursing: The Art & Science Patient-Centered Care, 9th Edition, Wolters Kluwer. 1.The net diffusion of water from one solution of water from one solution through a semipermeable membrane to another solution containing a lower concentration of water is termed: A. Filtration B. Diffusion C. Osmosis D. Brownian motion 2.Orly Khan is suffering from fluid volume deficit (FVD), which of the following symptoms would the nurse expect to assess in the patient? A. Rales B. Bounding pulse C. Tachycardia D. Bulging neck veins 3.John Reid is admitted to the hospital and is currently receiving hypertonic fluids. Nursing management for the client includes monitoring for all of the following potential complications except: A. Water intoxication B. Fluid volume excess (FVE) C. Cellular dehydration D. Cell shrinkage 4.Mr. Wenceslao is scheduled to receive an isotonic solution; which one of the following is an example of such a solution? A. D10% W B. 0.45% saline C. 0.9% saline D. 3% normal saline W 5.Which of the following blood products should be infused rapidly? A.Packed red blood cells (PRBC) B. Whole Blood C. Platelets D. Dextran 6.Which of the following statements provides the rationale for using a hypotonic solution for a patient with FVD? A.A hypotonic solution provides free water to help the kidneys eliminate the solute. B.A hypotonic solution supplies an excess of sodium and chloride ions. C.Excessive volumes are recommended in the early postoperative period. D.A hypotonic solution is used to treat hyponatremia. 7.The process of endocrine regulation of electrolytes involves: A.Sodium reabsorption and chloride excretion B.Chloride reabsorption and sodium excretion C.Potassium reabsorption and sodium excretion D.Sodium reabsorption and potassium excretion 8.Jonas is admitted with 1,000 ml of diarrhea per day for the last 3 days. An IV of 0.45% NaCl mixed with 5% dextrose is infusing. Which of the following nursing interventions is the most appropriate? A.Get an infusion controller from the central supply. B.Mix all antibiotics in 0.45% NaCl with 5% dextrose. C.Check the patient’s potassium level and contact the doctor for IV additive orders. D. Assess the patient for signs of hyperkalemia. 9.Mrs. Waltraud is receiving digoxin and Lasix daily. Today, she complains of nausea, and her apical pulse is 130 and irregular. Which of the following nursing interventions is the most appropriate? A.Hold the digoxin and check the patient’s potassium level. B.Remove the orange juice from the patient’s tray. C.Identify the patient as high risk for hyperkalemia. D.Assess the patient for other signs of hypernatremia. 10. A patient is admitted with exacerbation of congestive heart failure. What would you expect to find during your admission assessment?* A. Flat neck and hand veins B. Furrowed dry tongue C.Increased blood pressure and crackles throughout the lungs D.Bradycardia and pitting edema in lower extremities