fluid & electrolytes PDF

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Fluid & Electrolytes ch. 18 txtbook -

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Homeostasis: “balance” 4 elements in the body - Volume: amount of fluid in the body - Concentration: amount of stuff in the fluid - Electrolytes: important for vital processes in the body - pH: acidity or alkalinity of bloodstream in the body; if body is not in good pH the body won’t work - The body does this by constant movement (motion) of stuff; the body is always attempting to achieve homeostasis by constant movement of stuff Fluids (Water) - Carries good stuff to cells, carries waste away from cells - Provides a place or means for chemical reactions to occur - Either chemicals becoming more complex or making chemicals into more simpler ones → metabolism - Catabolism: body breaking down stuff - Anabolism: body is building up simple things to make complex things - Fluid (water) is vital for a chemical reaction to happen - Water lubricates tissues especially between joints - It maintains acid-base balance - Assists in heat regulation by evaporation; Heat regulation: dilating if its too hot, constricting if its too cold - Largest component of the body (50 to 80% of body weight) - The younger you are the more water you have (between 70%-80% in newborn) - Extracellular fluid is lost from the body more rapidly than intracellular fluid - A loss of 10% body fluid is serious; 20% is fatal Fluid Compartments - Intracellular (ICF): fluid inside the cells (66% or ⅔ of fluid inside the cells) - Cells are where metabolism happens - Interstitial (IF): fluid between cells (27% or ⅓) - If you have a lot of fluid is in the space you can have edema - Intravascular: water inside of the plasma; fluid within the blood vessel - Smallest amount of water is in the vessels (7%) - Extracellular: any fluid outside of the cells (ECF) - Refers to interstitial fluid and intravascular fluid - Contains large amounts of O2, CO2, as well as glucose, amino acids, fatty acids, Na, Ca, Cl, and bicarbonate - Electrolytes are moving in the intravascular to the interstitial compartment to have the right amount of stuff in the ECF, IF, ICF to have constant movement of stuff between each compartments - The body is trying to balance, electrolytes, fluid, pH and concentration

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Semipermeable: Intracellular and extracellular are separated by semipermeable membrane - This membrane allows for a constant flow as nutrients are taken into the cell and waste products are carried out - Permeable: ability for stuff to cross through - not everything is able to pass through - Things that are able to cross the semipermeable membrane are things that the cells needs or things the cells is discarding - Stuff cells discard: CO2, uric acid, wastes Channel protein: enable things to get into the cell and for things to leave the cell - Things are able to cross over without a channel as well Intake and Output - Refers to intake of fluid and output of fluid - As water moves through the body, fluid is lost and must be replaced - Water is used in the body to do metabolic things - We must replace the water (through drinking, IV fluids, eating food) - Average fluid intake: - Adult: 2200-2700 mL/day or 2L of fluid a day - Oral intake: 1100-1400mL/day - Solid foods provide 800-1000mL/day - Cellular metabolism provides 300mL/day - Thirst: body is telling you that you need fluid; when concentration in blood is high we get thirsty (thirst reflex is activated) - Concentration: amount of stuff in fluid - Sensible fluid loss: measurable fluid loss; (ie. urine, feces, vomiting, and wound drainage) - Insensible: fluid loss you can’t measure; (ie. breathing, sweating) - 300ml-500ml daily - Concentration: amount of stuff inside a fluid - When body senses there is a high concentration in blood stream it tells body to be thirsty (triggers thirst mechanism) - We get thirsty because the high concentration; when we add water it decreases concentration - Adding more water to the blood will decrease the concentration - High concentration means more particles less water - Less concentration means less particles more water - Diluting: decreasing concentration - Kidneys are primary regulators of fluid balance - 1L of fluid = 2.2 pounds which is equal to 1kg - Kidneys must secrete a minimum of 30mL/ hr to filter blood (< 30 is oliguria) - Specific gravity: measuring concentration of urine - If highly concentrated has more stuff

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- If less concentrated the body is more dilute Movement of Fluid & Electrolytes - Movement of stuff is natural phenomenon in nature - Things move naturally due to the law of physics - Body fluids are in constant motion (extracellular, intracellular) - Passive transport: stuff is moving from one compartment to another compartment without energy - Rolling a boulder down a steep mountain; bc no energy is required for the boulder to roll down Passive transport: (natural) transport: requires no energy - Easy for stuff to cross through - Happens everywhere in nature because of law of physics - 3 types of passive transport: diffusion, osmosis, filtration Diffusion: tendency of substances (electrolytes) to move from an area of higher concentration to a lower concentration - Electrolytes are moving not water ONLY ELECTROLYTES - Diffusion will stop when there is balance; equal amount of concentration Osmosis: movement of water across semipermeable membrane from an area of low concentration to an area of high concentration - Inside has low concentration; outside has more concentration - If water is added there is a (decrease in electrolytes (excess water dilutes electrolytes) - If there is high concentration in blood there is less water; electrolyte count will be high - Dilutes areas of higher concentration (decreases electrolyte count) - Osmosis stops when there is balance - Osmosis and diffusion happen simultaneously Osmotic preparations: IV fluids: goes directly into intravascular space which influences fluid in interstitial space (intracellular and interstitial is the same) - Isotonic (Normal saline): concentration is the same as the body’s (ie. NaCl = 0.9%) - Wont be any fluid shifting in the body because it is the same concentration - Hypertonic (D5): higher concentration of electrolytes than body fluids; shrink cells; pulls fluid from the cells WATER SHRINKS CELLS - Water will move from inside of cell to outside of cell (hypertonic solution) - Makes area around cells more concentrated - High concentration in blood stream will cause water to move from an area of low concentration to high concentration - Makes area around the cells MORE concentrated which makes water to move there - Give hypertonic solution when cells are large (edema)

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Hypotonic solution: IV infusion that is less concentrated than blood stream; WATER MAKES CELLS EXPAND (FATTER); makes outside of the cell MORE concentrated and inside is less concentrated - Use hypotonic solution if dehydrated to get water inside cells ASAP - Lowers concentration in blood stream - Filtration: using pressure to transfer; water and electrolytes to higher pressure from lower pressure Concentration: amount of electrolytes relative to fluid Active transport (ATP) requires energy; moving stuff from place to place with the use of energy - The Sodium-Potassium Exchange Pump: ATP will activate and open up carrier causing sodium to leave cell and potassium to go into the cell - ATP will open up the pump to allow potassium to go into the cell; to get molecules to move against pressure - NEED ENERGY TO GET POTASSIUM INSIDE (or electrolytes to move against pressure you need ATP (energy)) Electrolytes: develop energy, develops an electrical charge when it dissolves in water - Body is trying to achieve balance inside and outside of the cell (this happens by electrolytes moving) - Na & K are the primary electrolytes that generates electricity - Positively charged: cations - Negatively charged: anions - Body is trying to achieve electrical balance inside and outside the cells; this happens by electrolytes moving - Miliequivalents (mEq): measures chemical activity of an ion (electrolyte) - K, Ca, P, Na, Mg, and Cl is needed for metabolism - Metabolism is chemical reaction by these electrolytes ^^ - If electrolytes do not go where they need to then metabolism wont happen - Be aware of what each electrolyte does - Know the normal ranges - Know the manifestations of imbalances - Know the foods’ diet of these electrolytes Sodium: responsible for regulating fluid volume, contractility of muscle, maintains nerve conduction, acid base balance - Water follows sodium = trying to dilute sodium - Normal range: 135-145 mEq/L - Is Na is too low: fluid volume is messed up, muscle problems, nerve problems and acid base problems - Hyponatremia: Weakness, anorexia, muscle cramps, confusion, fatigue, headache, edema, seizures - Hypernatremia: dehydration; potassium imbalances

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Concentration of Na is high because of dehydration Sodium rich foods: cheese, table salt, seafood, processed meat, canned vegetables, canned soups, ketchup, and snack foods, such as pretzels and potato chips Potassium: regulates water and electrolyte content, promotes transmission of nerve impulses and skeletal muscle function, regulates hydrogen ions and thus acid-base balance; too little or too much potassium affect the heart - Hydrogen ions are very acidic - Normal: 3.5- 5.0 mEq/L - Hypokalemia: renal excretion and GI losses; effects skeletal and cardiac function; life threatening - Potassium rich foods: orange, potatoes, apricots, peaches Chloride: (extracellular): helps with gastric secretions and acid-base balance - Usually bound to another ion - Normal: 96- 106 mEq/L - GI problems and acid-base problems - Hypo: vomiting, diarrhea, gastric suctioning and infection Calcium: (bones and teeth) - When calcium levels fall; calcium from bones and teeth release into the blood stream - Responsible for: blood clotting, promotes muscle contraction, and promotes normal nerve impulses, holds cells together by establishing thickness - Normal: 4.5-5.6 mEq/L - 2 ways to check for calcium: Chvostek’s sign (cheek); Trousseau sign (inflating BP cuff; arm curls inward) - Hypocalcemia: neuromuscular irritation, increased excitability, hyperactive reflexes, seizures, tetany - Hypercalcemia: renal calculi: (stones), excretion of high levels of calcium secreted by kidneys - Foods: cheese. Milk, beans ,nuts, cauliflower, lettuce, eggs, green leafies, anything with bones (fish) Phosphorus: found in bones and teeth; inverse relationship with calcium - Makes the cell membrane (cell structure) - Essential component of phospholipids (structural components of cell membranes); acid-base balance; promotes effectiveness of many B vitamins; normal nerve and muscle activity, needed in carbohydrate metabolism - Normal: 2.4-4.1 mEq/L - Foods: legumes, beef, pork, fish poultry, milk Magnesium: intracellular; regulates calcium, phosphate, potassium; activates many enzymes - Normal 1.5 to 2.5 mEq/L

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Hypo: neuromuscular irritability, tremors, cramping, numbness, tingling, disorientation, confusion, tetany, seizures - Hyper: severely restricts nerve and muscle activity, causes respiratory depression, hypotension, cardiac arrest Bicarbonate (EXTRACELLULAR) HCO; made in the kidneys and dropped off in the blood stream - Alkaline electrolyte: regulates acid-base balance - Normal: 22- 24 mEq/L - Bicarbonate acts like a sponge; when it comes in contact with hydrogen ion, it binds together to make H2CO; neutralized hydrogen so hydrogen will not be acidic anymore; soaks up acidic hydrogen in the blood Acid-Base Balance - pH of the blood - Normal: 7.35-7.45 - Low pH is more acidic; high is more alkaline - Refers to the homeostasis of the hydrogen ion concentration in the body fluids; hydrogen is acidic; the more hydrogen in the body means more acidic; the less hydrogen more alkalinic - Refers to amount of hydrogen in the blood stream - If you do not have the proper amount of hydrogen int he blood stream - The body has three systems that work to keep the pH normal: blood buffers, respiratory system and the kidneys - Blood buffers: - Bicarbonate:binds with hydrogen ions to not make them acidic anymore; decreases strength of potentially damaging acids - Respiratory system: - Exhaling: CO2 is acidic, breathing out will make pH more basic (alkalinic) - Respirations will be very fast if pH is acidic because the body is trying to compensate by getting rid of CO2 (which is acidic) - Kidneys: weakest mechanism; regulates pH by excreting acids and bases as needed; also forms bicarbonate - DKA: blood sugar is so high because body is lacking insulin Respiratory Acidosis: difficulty exhaling, caused by any condition impairing normal ventilation and preventing the respiratory system from eliminating appropriate amount of CO2 (COPD, emphysema) - Chest expands Respiratory Alkalosis: - Exhaling more than inhaling; putting out more CO2 then able to inhale; Alkalinic - Ie. asthma - Blood buffers: slows down HCO

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- Respiratory: slows down respirations - Urine: excretes basis Metabolic acidosis: non respiratory problem that makes you acidic (endocrine problem, renal failure, DKA) can’t eliminate uric acid (no uric acid excretion) this makes body more acidic - Blood buffers: increase HCO - Respiratory: respirations will go up - Urine: excretes uric acid Metabolic alkalosis: significant amount of acid is lost from the body; hyperventilating - Blood buffers: decrease HCO (HCO is basic) - Respirations: decrease respirations because we want to save as much CO9 (acid) as possible to decrease pH - Kidney: hold acid, but excrete HCO/ bases Intravenous Therapy - Know what PH imbalance looks like = bad - Know how body brings back to pH - Infiltration & phlebitis - Infiltration: seeping solution into tissues surrounding the vessel; if edematous, loosen the tape over site and observe → stop the IV and reinsert new one you will feel coldness - Phlebitis: inflammation of the vein, comes from heat - Septicemia: when microorganisms enter the blood...