Presentation on theme: "Stressors Affecting Fluid & Electrolyte Balance NUR 101 FALL 2008 LECTURE # 15 & #16 K. Burger, MSEd, MSN, RN, CNE."— Presentation transcript:
Stressors Affecting Fluid & Electrolyte Balance NUR 101 FALL 2008 LECTURE # 15 & #16 K. Burger, MSEd, MSN, RN, CNE
Body Fluids Water= most important nutrient for life. Water= primary body fluid. Adult weight is 55-60% water. Loss of 10% body fluid = 8% weight loss SERIOUS Loss of 20% body fluid = 15% weight loss FATAL Fluid gained each day should = fluid lost each day (2 -3L/day average) What is the minimum output per hour necessary to maintain renal function? 30ml/hr
Functions of Body Fluid Medium for transport Needed for cellular metabolism Solvent for electrolytes and other constituents Helps maintain body temperature Helps digestion and elimination Acts as a lubricant
Mechanisms of Fluid Gain and Loss Gain Fluid intake 1500ml Food intake 1000ml Oxidation of nutrients 300ml (10ml of H20 per 100 Kcal) Loss “Sensible” Can be seen. Urine 1500ml Sweat 100ml “Insensible” Not visible. Skin (evaporation) 500ml Lungs 400ml Feces 200ml
Regulation of Fluids Hypothalmus –thirst receptors (osmoreceptors) continuosly monitor serum osmolarity (concentration). If it rises, thirst mechanism is triggered. + Vasopressin (AKA ADH )– increasing H20 reabsorption Pituitary regulation- posterior pituitary releases ADH (antidiuretic hormone) in response to increasing serum osmolarity. Causes renal tubules to retain H20. Thirst is a late sign of water deficit
Regulation of Fluids ( continued ) Renal regulation- Nephron receptors sense decreased pressure (low osmolarity) and kidney secretes RENIN. Renin – Angiotensin I – Angiotensin II Angiotensin II causes Na and H20 retention by kidneys AND….. Stimulates Adrenal Cortex to secrete Aldosterone which causes kidneys to excrete K and retain Na and H20.
Consider This…. The Geriatric Client -normal physiological aging results in decreased thirst mechanism decreased # of sweat glands decreased renal function -there also may be decreased mobility and/or cognitive function which impacts their ability to get adequate fluid intake.
Variations in Body Fluids Elderly: Have lower % of total body fluid than younger adults Women: Have lower % total body fluid than men WHY DO YOU THINK THIS IS ????? Muscle tissue has more H20 content THAN adipose tissue
Fluid Compartments Intracellular fluid (ICF) Fluid inside the cell Most (2/3) of the body’s H20 is in the ICF. Extracellular Fluid (ECF) Fluid outside the cell. 1/3 of body’s H20 More prone to loss 3 types: Interstitial- fluid around/between cells Intravascular- (plasma) fluid in blood vessels Transcellular –CSF, Synovial fluid etc
Consider this…. Age variations exist in regards to H20 content of fluid compartments Infants = 60% of H20 is found in ECF 40% of H20 is found in ICF What might this mean in regards to fluid loss for an infant? Reverse of adults! Infant MORE PRONE to fluid LOSS!
Fluid Balance Dynamic process Balance between body fluids and electrolytes Attraction between ions (electrolytes) and water (fluids) causes fluids to move across membranes and leave their compartments.
Solvent (H20) Movement Cell membranes are semipermeable allowing water to pass through Osmosis- major way fluids transported Water shifts from low solute concentration to high solute concentration to reach homeostasis (balance).
Osmolarity Concentration of particles in solution The greater the concentration (Osmolarity) of a solution, the greater the pulling force (Osmotic pressure) Normal serum (blood) osmolarity = mOSM/kg A solution that has HIGH osmolarity is one that is > serum osmolarity = HYPERTONIC solution A solution that has LOW osmolarity is one that is < serum osmolarity = HYPOTONIC solution A solution that has equal osmolarity as serum = ISOTONIC solution
Hypertonic Fluids Hypertonic fluids have a higher concentration of particles (high osmolality) than ICF This higher osmotic pressure shifts fluid from the cells into the ECF Therefore Cells placed in a hypertonic solution will shrink
Hypertonic Fluids Used to temporarily treat hypovolemia Used to expand vascular volume Fosters normal BP and good urinary output (often used post operatively) Monitor for hypervolemia ! Not used for renal or cardiac disease. THINK – Why not? D5% 0.45% NS D5% NS D5% LR Pulmonary Edema
Hypotonic Fluids Hypotonic fluids have less concentration of particles (low osmolality) than ICF This low osmotic pressure shifts fluid from ECF into cells Cells placed in a hypotonic solution will swell
Hypotonic Fluids Used to “dilute” plasma particularly in hypernatremia Treats cellular dehydration Do not use for pts with increased ICP risk or third spacing risk 0.45%NS 0.33%NS
Isotonic Fluid Isotonic fluids have the same concentration of particles (osmolality) as ICF ( mOsm/L) Osmotic pressure is therefore the same inside & outside the cells Cells neither shrink nor swell in an isotonic solution, they stay the same
Isotonic Fluid Expands both intracellular and extracellular volume Used commonly for: excessive vomiting,diarrhea 0.9% Normal saline D5W Ringer’s Lactate
Other Osmotic Factors ALBUMIN ( a serum protein ) Albumin in the serum has osmotic properties called colloid pressure Albumin pulls H20 from the interstitial compartments into the intravascular compartments (serum). Helps to maintain BP. Persons with low serum albumin levels tend to retain fluid in their interstitial layers. What abnormal assessments might you find in the client with low serum albumin levels? Edema, hypotension
Hmmm……. What type of IV fluid (hypotonic – isotonic – hypertonic) might be of benefit to this client with low albumin levels?
Consider this…. When tissue injury occurs, proteins pathologically leak from the intravascular space into the intersititial space. Termed: Third spacing This explains __________ as a sign of the inflammatory process. EDEMA
Solute Movement - Diffusion Movement of solutes from high concentration to low concentration It is a PASSIVE movement DOWN the concentration gradiant. (requires no energy) Many body processes use diffusion. Example: O2 and CO2 exchange Rate is affected by: concentration gradiant, permeability-surface area-thickness of membranes, and size of particles. (Fick’s Law)
Solute Movement –other mechanisms Active transport- requires energy (ATP) to move from low concentration to high concentration (uphill) Example: Na / K pump May be enhanced by carrier molecules with binding sites on cell membrane Example: Glucose (Insulin promotes the insertion of binding sites for Glucose on cell membranes).
Filtration Solvent AND solute movement Passage from an area of High Pressure to an area of Low Pressure Termed: Hydrostatic Pressure Example: Arterioles have higher pressure than ICF Fluid, oxygen and nutrients move into cells Venules have lower pressure than ICF Fluid, carbon dioxide and wastes move out of cells
Fluid volume deficit FVD (Hypovolemia) Loss of both H20 and electrolytes from ECF. Causes include: Increased output, Hemorrhage, vomiting, diarrhea, burns, OR Fluid shift out of vascular space ( “third spacing” ) into interstitial spaces
Dehydration Isotonic dehydration = H20 & electrolyte loss in equal amounts; diarrhea and vomiting Hypertonic dehydration = H20 loss greater than electrolyte loss; excessive perspiration, diabetes insipidus
Assessment FVD - Hypovolemia Cardiovascular: Diminished peripheral pulses; quality 1+(thready) Decreased BP & orthostatic hypotension Increased HR Flat neck & hand veins in dependent position Elevated Hematocrit (Hct) Gastrointestinal: Thirst Decreased motility; diminished bowel sounds, possible constipation
Assessment FVD – Hypovolemia (continued) Neuromuscular: Decreased CNS activity (lethargy to coma) Possible fever Skeletal muscle weakness Hyperactive DTR Renal: Decreased output Increased spec grav of urine Weight loss Hypernatremia Integumentary: Dry mouth & skin Poor turgor (tenting) Pitting edema Sunken eyeballs Respiratory: Increased rate and depth
Nursing Diagnosis - FVD Deficient Fluid Volume R/T loss of GI Fluids via vomiting AEB elevated Hct, dry mucous membranes, decreased output, thirst
Planning - FVD Client will demonstrate fluid balance aeb moist mucous membranes, balanced I & O measurements, Hct WNL, by ….
Interventions for FVD - Hypovolemia Prevent further fluid loss Oral rehydration therapy IV therapy Medications; antiemetics, antidiarrheals Monitor CV, Resp, Renal, GI status Monitor electrolytes – possible supplement rx MONITOR WEIGHT and I & O
NCLEX Practice Intravenous fluids are ordered for your client who is experiencing diarrhea and vomiting for the past 2 days. Which IV solution would the nurse expect to see prescribed? a. D 5 NS b. 0.45%NS c. D 5 1/2NS d. RL
Fluid Volume Excess FVE - Hypervolemia Fluid overload is an excess of body fluid - overhydration Excess fluid volume in the intravascular area-hypervolemia Excess fluid volume in interstitial spaces edema
Fluid Volume Excess Causes: Increased Na/H2O retention Excessive intake of Na (PO or IV) Excessive intake of H2O ( PO or IV) (Water intoxication) Syndrome of inappropriate antidiuretic hormone (SIADH) Renal failure, congestive heart failure
Planning - FVE Client will demonstrate fluid balance by balanced I & O measurements, Serum Na WNL, etc. by ….
Interventions FVE - Hypervolemia Restore normal fluid balance, prevent further overload Drug therapy; diuretics Diet therapy; decrease Na & fluids Monitor intake and output (I & O) Monitor weights Monitor electrolytes Monitor CV, Resp, Renal systems
Clinical Application You have been assigned to care for an 80y.o. client admitted with hypernatremia that has an IV infusing 0.45% 100ml/hr via pump and an indwelling urinary catheter. At 11am you assess an output in the urinary drainage bag of 150ml dk amber urine. You also notice that the client is SOB while speaking on the phone to her daughter. What do you think is happening?? What will you do??
SUMMARY Want more Information??? CHECK OUT THE WEBLINKS For Chapter 41 on EVOLVE
Electrolytes Work with fluids to keep the body healthy and in balance They are solutes that are found in various concentrations and measured in terms of milliequivalent (mEq) units Can be negatively charged (anions) or positively charged (cations) For homeostasis body needs: Total body ANIONS = Total body CATIONS
Electrolyte Functions Regulate water distribution Muscle contraction Nerve impulse transmission Blood clotting Regulate enzyme reactions (ATP) Regulate acid-base balance
Sodium Na mEq/L Major Cation Chief electrolyte of the ECF Regulates volume of body fluids Needed for nerve impulse & muscle fiber transmission (Na/K pump) Regulated by kidneys/ hormones
Hmmm… Hyper and Hypo Natremia are the most common electrolyte disturbances. Why do you think that is? It is most abundant in the EXTRACELLULAR FLUID and therefore more prone to fluctuation.
Hyponatremia Serum Na+ <135mEq/L Results from excess of water or loss of Na+ Water shifts from ECF into cells S/S: abd cramps, confusion, N/V, H/A, pitting edema over sternum Tx: Diet/IV therapy/fluid restrictions
Lets think about … Hyponatremia What are some medical conditions that may cause a dilutional hyponatremia? CHF Renal Failure SIADH ( Cancer, pituitary trauma ) Addisons Disease ( hypoaldosteronism & Na loss ) What are some conditions that might cause actual loss of sodium from the body? GI losses – nasogastric suctioning, vomiting, diarrhea Certain diuretic therapies Permanent neurological damage can occur when serum Na levels fall below 110 mEq/L. Why? Hypotonic environment swells cells, increasing ICP – brain damage
Hypernatremia Serum Na+> 145mEq/L Results from Na+ gained in excess of H2O OR Water is lost in excess of Na+ Water shifts from cells to ECF S/S: thirst, dry mucous membranes & lips, oliguria, increased temp & pulse,flushed skin,confusion Tx: IV therapy/diet
Let’s think about…. Hypernatremia What are some medical conditions that may cause elevated serum Na? Renal failure Diabetes Insipidus Diabetes Mellitus ( hyperglycemic dehydration) Cushings syndrome (hyperaldosteronism) What are some other patient populations at risk for hypernatremia? Elderly ( decreased thirst mechanism ) Patient’s receiving: -tube feedings -corticosteroid drugs -certain diuretic therapies Seizures, coma, death my result if hypernatremia is left untreated. Why? Cells loose fluid into the ECF causing irreversible cell damage.
Critical Thinking Hypo / Hyper Natremia For the client experiencing FVE & hyponatremia d/t excessive intake of water, which IV solution would you expect the physician to order? a. D5NS b. NS c. D5W d. ½ NS For the client experiencing FVD and hypernatremia d/t excessive water loss, which IV solution would you expect the physician to order? a. D5 ½ NS b. D5RL c. D5W d. ½ NS
Potassium K mEq/L Chief electrolyte of ICF Major mineral in all cellular fluids Aids in muscle contraction, nerve & electrical impulse conduction, regulates enzyme activity, regulates IC H20 content, assists in acid-base balance Regulated by kidneys/ hormones Inversely proportional to Na
Hypokalemia Serum level < 3.5mEq/L Results from decreased intake, loss via GI/Renal & potassium depleting diuretics Life threatening-all body systems affected S/S muscle weakness & leg cramps, decreased GI motility, cardiac arrhythmias Tx: diet/supplements/IV therapy
Lets think about … Hypokalemia What are some medical conditions that may cause a hypokalemia? Renal Disease / CHF (dilutional) Metabolic Alkalosis Cushings Disease ( Na retention leads to K loss ) What are some conditions that might cause actual loss of potassium from the body? GI losses – nasogastric suctioning, vomiting, diarrhea Certain diuretic therapies Inadequate intake – ( body cannot conserve K, need PO intake) Cardiac arrest may occur when serum K levels fall below 2.5 mEq/L. Why? Increased cardiac muscle irritability leads to PACs and PVCs, then AF
Hyperkalemia Serum level >5 mEq/L Results from excessive intake, trauma, crush injuries, burns, renal failure S/S muscle weakness, cardiac changes, N/V, parathesias of face/fingers/tongue Tx:diet/meds/IV therapy/ possible dialysis
Lets think about … Hyperkalemia What are some medical conditions that may cause hyperkalemia? Renal Disease=most common cause Burns and other major tissue trauma Metabolic Acidosis Addison’s Disease ( Na loss leads to K retention ) What are some conditions that might cause potassium levels to rise in the body? Certain diuretic therapies Excessive intake – ( inappropriate supplements) Cardiac arrest may occur when serum K levels rise above mEq/L. Why? Decreased electrical impulse conduction leads to bradycardia and eventual asystole.
Critical Thinking Potassium IV additives Which of the following interventions will the nurse undertake when administering parenteral K additives? Monitor the IV site for phlebitis Place on cardiac monitor if > 10 mEq Assure of adequate mixing of K in solution Monitor for elevated K levels Monitor for decreased Na levels Administer potassium by slow IV push method NEVER!!!
Calcium Ca mEq/L Most abundant in body but: 99% in teeth and bones Needed for nerve transmission, vitamin B12 absorption, muscle contraction & blood clotting Inverse relationship with Phosphorus Vitamin D needed for Ca absorption
Lets think about … Hypocalcemia What are some medical conditions that may cause hypocalcemia? Hypoparathyroidism (low PTH levels = decreased release of Ca from bones) S/P thryoid surgery ( low Calcitonin = decreased release of Ca from bones) Acute pancreatitis Crohns Disease Hyperphosphatemia ( ESRF) What are some other conditions that might cause low Ca? GI losses – nasogastric suctioning, vomiting, diarrhea Long term immobilization Lactose intolerance If hypocalcemia is prolonged, the body will utilize stored Ca from bones. What complication might arise? Fractures ( late sign )
Hypercalcemia Serum Ca > 5.3mEq/L Results from hyperparathyroidism, some cancers, prolonged immobilization S/S muscle weakness, renal calculi, fatigue, altered LOC, decreased GI motility, cardiac changes Tx: medication/ IV therapy
Lets think about … Hypercalcemia What are some medical conditions that may cause hypercalcemia? Hyperparathyroidism (high PTH levels = increased release of Ca from bones) Paget’s Disease Some Cancers – Multiple Myleoma Chronic Alcoholism ( with low serum phosphorus ) What are some other conditions that might cause low Ca? Excessive intake of Ca OR Vitamin D Excessive intake of OTC antacids If hypercalcemia is uncorrected, AV block and cardiac arrest may occur.
Magnesium Mg mEq/L Most located within ICF Needed for activating enzymes, electrical activity, metabolism of carbs/proteins, DNA synthesis Regulated by intestinal absorption and kidney
Hypomagnesemia Serum < 1.5mEq/L Results from decreased intake, prolonged NPO status, chronic alcoholism & nasogastric suctioning S/S: muscle weakness, cardiac changes, mental changes, hyperactive reflexes & other hypocalcemia S/S. Tx: replacement IV therapy restore normal Ca levels ( Mg mimics Ca) seizure precautions
Hypomagnesemia Common in critically ill patients Associated with high mortality rates Increases cardiac irritability and ventricular dysrhythmias - especially in patients with recent MI Maintenance of adequate serum Mg has been shown to reduce mortality rates post MI
Hypermagnesemia Serum>2.5mEq/L Results from renal failure, increased intake S/S: flushing, lethargy, cardiac changes (decreased HR),decreased resp, loss of deep tendon reflexes Tx: restrict intake diuretic rx
Chloride Cl mEq/L Most abundant anion in ECF Combines with Na to form salts Maintains water balance, acid-base balance, aids in digestion (hydrochoric acid) & osmotic pressure (with Na and H20) Regulated by kidneys Follows Sodium (Na)
Hypochloremia Serum level 96mEq/L Results from prolonged vomiting & suctioning S/S metabolic alkalosis, nerve excitability, muscle cramps, twitching, hypoventilation, decreased BP if severe Tx: diet/IV therapy
Hyperchloremia Serum level > 106mEq/L Results from excessive intake or retention by kidneys – metabolic acidosis S/S Arrhythmias, decreased cardiac output, muscle weakness, LOC changes, Kussmauls’s respirations Tx: restore fluid & electrolyte balance
Phosphate PO mg/dl Needed for acid-base balance,neurological & muscle function, energy transfer ATP & affects metabolism of carbs/proteins/lipids, B vitamin synthesis Found in the bones Regulated by intake and kidneys Inversely proportional to Calcium Therefore some regulation by PTH as well
Hypophosphatemia Serum level < 1.8mEq/L Results from decreased intestinal absorption and increased excretion S/S bone & muscle pain, mental changes, chest pain, resp. failure Tx: Diet/ IV therapy
Hyperphosphatemia Serum level> 2.6mEq/L Results from renal failure, low intake of calcium S/S: neuromuscular changes (tetany), EKG changes, parathesia-fingertips/mouth Tx: Diet; hypocalcemic interventions Medications: phosphate binding The body can tolerate hyperphosphatemia fairly well BUT the accompanying hypocalcemia is a larger problem!
Critical Thinking - NCLEX The nurse is caring for a client with renal failure whose magnesium level is 3.6 mg/dL. Which of the following signs would the nurse most likely expect to note in the client based on this Mg level? a. Twitching b. Hyperactive reflexes c. Irritability d. Loss of deep tendon reflexes
Electrolyte homeostasis This means to maintain balance… to control by balancing the dietary intake of electrolytes with the renal excretion and reabsorption of electrolytes
Interventions for F/E balance Assess patient carefully- note changes Monitor I & O (Intake & Output) Monitor weight changes Monitor urine Monitor vs Monitor lab results and dx test Maintain proper IV therapy
Summary Fluid compartments in the body must balance Body systems regulate F&E balance Assessment of body fluid is important to determine causes of imbalance Interventions for imbalances are based on the cause