Fluids and Electrolytes (Autosaved) PDF

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Prof. Zimmer...

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Fluids and Electrolytes Definition:  Concept refers to “process of regulating extracellular fluid volume, body fluid osmolality, and plasma concentration of electrolytes”. o Maintaining homeostasis o Fluid and osmolality stay within normal limits  Dynamic interplay between three processes: o Intake and absorption: addition of F&E to the body (intake) and their movement into the blood (absorption)  Going from GI tract into blood stream o Distribution: process of moving fluid between compartments, moving that fluid from intravascular to interstitial  Going from cell to extracellular o Output: removal of F&E from the body via normal or abnormal routes  How we get rid of the excess fluid, how we get rid of excess electrolyte  Conceptually: “optimal balance”, “too much” or “too little” o Body try to fix itself to keep everything within normal limits o It’s when the body can’t fix it self that we intervene  Ex. Kid with GI bugs, the first thing that doctors tell parents to do when thy have diaherra and vomiting is to give them fluids and not meds rt away

Conceptually:  Fluid Balance: extracellular volume and osmolality  Electrolyte Balance: extracellular fluid volume, body fluid osmolality and plasma electrolyte concentration on a continuum

Osmolality:  “Concentration of molecules per weight of water” o ratio of particles in the blood to the liquid portion o eating salty chip and drinking water – if the same amount then not changing the ratio  “Number of dissolved particles per unit of water”  When the amount of water decreases in relation to # particles, the osmolality increases and becomes concentrated o Blood becomes more concentrated, hyperosmolar  When the amount of water increases relative to solutes the osmolality decreases and becomes more diluted o Blood becomes diluted, hypoosmolar  The primary particle responsible for regulating osmolality is sodium

Osmolality Changes  Hyper-osmolality: cells shrinking – dehydration o Intravascular, extracellular – blood is concentrated o Cells are going to want to give blood more fluid o Fluid will leave the cell into the bloodshrinking the cells which leads to dehydration  SS – poor skin turgor, dry mucus membrane, decrease urine output, increase HR, possible high temperature  HR-compensatory mechanismnot enough fluid in the system, pump harder, pump faster  Hypo-osmolality: cells swelling – water gain o Blood in the system is dilute, too much fluid o Cell are taking in some water o Cell are swelling, excess watercerebral edema, swelling in the brain  SS – weight gain, increase BP, SOB, crackles in lungs, edema, same HR-bounding pulses, increase urine output Intake and Absorption and Distribution

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Different processes that are at work to keep that balance Most fluid intake = oral thru GI system Fluid electrolytes has to be absorbed if taken thru oral For IV electrolytes we can skip the absorption step, because it goes directly into the vascular system Abnormal drainage  we have to give more fluid intake to make up for that (NG tube, Wound bag, Gtube) o Have to make sure we make up for those fluid lost Excretion skin, lung, kidneys, bowels

Intake and Absorption     

Oral IV Less common: insertion into rectum, nasogastric (NG) or gastrointestinal tract, infusion into body cavities, bone marrow (intraosseous) Mechanism for oral intake: thirst - stimulated by increased osmolality and receptors for hypovolemia Electrolytes (except IV route) must be absorbed by body o Ca+: intestine (duodenum) and requires Vitamin D  Absorbed thru the intestine  Pt that has bowel obstruction, colonstmy etc worry about do they have enough calcium in the body  Also worry about whether or not they have enough Vitamin D in body if they do not then calcium is not gonna be absorbed properly o Mg++ : intestinal epithelium of ileum  Alcoholic ptcauses damage to the intestinal lining

DISTRIBUTION  

F&E are distributed in various body compartments Total Body water – 60% (average*) of total body weight o Mostly made up of water o *(approximately 55% female and 65% male)

INTRACELLULAR vs. EXTRACELLULAR (Distribution) Intracellular  intra –inside  skeletal muscles – largest area  2/3 of our fluids  Largest component  Most found in skeletal muscle cells  Function – help balance and maintain the osmolality, help with all the metabolic processes that happens in the cell, it provides as cushioning for the cells and tissues

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Extracellular Extra – outside the cell 1/3 of the fluids interstitial and plasma makes up our extracellular Compartments - Interstitial - fluid outside the blood vessel but surrounds the cell - fluid that cushions the cells - Intravascular -plasma, in the vascular system - Transcellular -special, cut off from the cells -lymph fluid, peritoneal cavity, pleural fluids (outside the lungs but under the sack surrounding the lungs), synovial joints, cerebral spinal fluid

Fluid Movement  Fluid movement between the cell and outside the cell (extracellular) happens by osmosis o Happens when there is a change in osmolality o Fluid movement between what’s inside the blood vessel and what’s outside the blood vessel  Intracellular and interstial  2 pressures that effects the fluid shifts, happens all the time so your heart is not overwhelmed  Shifting happens 24/7 to keep body balanced  Ex. Pt has procedure down and give whole liter of isotonic IV fluid, so its gonna stay in the BV and expand the BV, normal healthy, these processes are going to be in place to help get rid of that excess liter of IV fluid, constant exchange of fluid taking place, kidneys kick in, heart will try to get rid of the extra volume

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Hydrostatic Pressure o Pressure placed on the blood vessel by the amount of fluid going thru the vessel o Influenced by blood pressure and volume o The higher the BP the higher the hydrostatic pressure o The higher the volume of blood pulsing thru the higher the hydrostatic pressure o Pushes fluid out of capillary out into the interstitial spaces o Relieve that large amount of volume from blood vessel  Ex. After procedure with isotonic IV fluid pt had high hydrostatic pressure because of the high fluid volume, body gonna push fluid out of vascular system into interstitial spaces o Higher hydrostatic pressure is generally at the arterial end of the capillary  Colloidal Osmotic Pressure o Exerted by plasma proteins  Plasma proteins are needed to create colloidal osmotic pressure o Draws fluid back into capillary  Need that because we have waste products in the interstitial space, the waste product (unoxygenated blood) has to come back in to our blood system to run back thru the veins and into the heart to be oxygenated o Higher inside the capillary at the venous end o Functions to pull fluid back in o Not enough proteinfluid will stay in the interstitial spaces then pt will have edema  Low BP, low urine output, increase HR, build of waste product in body *Direction of fluid depends on the difference of the opposing forces

Protein Influence  Protein Deficiency o Causes:  Inadequate protein intake  Protein loss  Third world countriesPpl will be skin and bloated stomach, wasted muscle mass, poor teeth, hair loss o Bloated stomach fluid is accumulating in the peratial cavity  Decreased protein synthesis o Manifestations:  What would the nurse expect to assess in the patient?  Low BP  Lower urine output  Increase HR  Skinny/ thin  Bloated stomach  Wasted muscles mass- no muscle in arms and legs  Poor teeth  Hair loss  EDEMA – major assessments in pt with protein defincency  Pitting – how deep u can push in, and indent when you press on pt skin o Front of shin, ankles as well o Grade it by how long it returns back and how deep we can push o Mostly protein defeinceny  Dependent – lower extremities, ppl on their feet for a long time with extra weight they’re carrying around o prego woman o Obese pt o Pt with vascular issues o Look for edema in pt in bed  Will decrease when u change position  Weeping – skin is pulled so tight from all the excess fluid that the fluid is coming out  Anasarca – all over, generalized edema  Periorbital edema, cybes (excess fluid in abdomen)

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Collaborative Care: o Diet high in Carbohydrates and Protein – Why both?  Just protein they going to use that up rt away, need carbs to use that up as energy and protein gets stored  Want them to store the protein for when the cells are injured  PO or tube feedings thru GI tract, NG tube or G tube o IV or tube feeding with amino acids  Total parental Electrolytes:  Sodium (Na+) – high extracellular pool concentration, a lot in blood vascular system o reflects osmolality o highest range o highest normal range because blood system is where we drawing the blood  Potassium (K+) – high intracellular pool concentration o Lives inside the cells o 3.5-5 o main home not in the vascular system  Calcium (Ca++) - Bone pool o Lives in the bones o Calcium is needed to grow our bones and strong bones  Magnesium (Mg++) – intracellular and bone pool o In the cell and in the bone o Very low Factors influencing distribution:  Hormones  Diets  Diseases/conditions Balance  Electrolytes o Sodium (Na+)……………………....135 - 145 mEq/L o Chloride (Cl-)………………….…….97 - 107 mEq/L o Potassium (K+)………………….….3.5 - 5.0 mEq/L o Calcium (Ca++)……………….……..8.2 - 10.2 mg/dL o Phosphorus (PO4-)……………….2.5 - 4.5 mg/dL o Magnesium (Mg++)……………….1.6 - 2.6 mg/dL o Bicarbonate (HCO3-)……………..22 - 26 mEq/L

Output  Normal Excretory Routes: o Kidneys  Make sure they’re kidneys are working before giving them potassium  80% of potassium is regulated thru the kidneys  if giving potassium to pt MAKE SURE THAT THEIR KIDNEYS ARE WORKING!!! o Skin  Sensible Perspiration – perspiration in an enough amount that we can see it, we can fell it  Insensible Perspiration – minimal amount of fluid that we lose at any given time that we don’t feel it, because it such a low amount o Lungs – we do lose fluid thru respiration o Gastrointestinal Tract – feces  Abnormally diarrhea, vomiting, hemorrhaging, any drainage  Abnormal Excretory Routes: o Emesis o Hemorrhage o Drainage (fistulas, tubes etc.)  Renal Excretion o Antidiuretic Hormone (ADH) – regulates excretion of water only  Regulated by volume of water in the system  If out body sense that the volume of water is getting too low (hypovolemic), we will have an increase of ADH secretion  We will want to keep urine in, not allowing it to go out  Increase in ADH = increase the amount of urine in the body o Just water not the salt o Just keeping the water will effect osmolality  Too much ADH, risk the chance of diluting sodium, pt will experience HYPONATRIUM (not enough salt compared to amount of water in body)  Secreted according to the volume of water  ADH has the ability to increase or decrease osmolality o Aldosterone – retains Na+ & water and promotes renal excretion of K+  The more aldosterone body makes the more potassium the body loses  Stimulated to secrete based on osmolality, volume too but only volume related to osmolality  Aldosterone is going to retain both sodium and water together  Increase in aldosterone secretion, increase of retention of sodium and water together  Aldosterone will help increase volume in blood system that will increase pressure in blood system  However, it will NOT correct osmolality.  Calculation of Fluid Loss o 1 L of water = 2.2 lbs. (1 kg) o weight is the most accurate measurement of how much fluid is lost or how much fluid is gained  dehydration or fluid excess ***Can calculate amount of fluid loss/gained via weight change***

Regulatory Mechanisms  Homeostasis achieved by… o Renal System  maintain balance renal system is triggered by ADH and aldosterone o Hormonal System  when we’re losing fluid volume ADH will be stimulated, retain that fluid, kidneys are triggered by ADH o Respiratory System  Blow off more gases, and blow off more insensible fluid lost Diagnostic Lab Tests  CBC (Complete Blood Count) o Hemoglobin and hematocrit o Different ranges for male and female o Will go up if pt is dehydrated o Will go down if pt is fluid overloaded  Electrolytes  Serum Creatinine (0.5-1.2mg/dL) o Kidneys o Pt dehydrated - elevated  BUN (Blood Urea Nitrogen) o 8-21mg/dL o are kidneys working? o dehydrated - elevated  Plasma Proteins o Total Proteins: 6.4-8.3g/dL o Albumin: 3.5 – 5.0 g/dL o Edema – have enough plasma protein present  Urine & Serum Osmolality o Table 8.2 – Normal ratio is 3:1  Routine Urinalysis (U/A) o Specific Gravity – 1.005-1.030 o Infection, ketones, protein, prego woman o High number = pt dehydrated  WORRY MORE ABOUT A HIGH NUMBER

Concept Categories

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Which condition(s) will have fluid shifting? 3 different potential problems when talking about F&E imbalances 1. F&E imbalances involving extracellular fluids, in the plasma and in the interstitial spaces 2. Osmolality – solutes in relation to how much volume we have a. Can be too low or too high, or it can normal and extracellular fluid is off 3. We can have an electrolyte imbalance w/o a fluid imbalance a. But if sodium is off, we definitely have an osmolality imbalance b. However, our other electrolyte can be imbalanced but our fluid could be ok Any combo of things going on Do a good health history to see what brought them in Increase in extracellular volume in the plasma of the bloodhypervolemia extra fluid will be pulled into the interstitial spaces o Osmolality is going to be going to be ok Not enough fluid in the plasma of the blood fluid from interstitial spaces will go back into the cell Hypo-osmolar, sodium is low plasma fluid will shift into the cells Hyperosmolar, sodium is high fluid flow out of the cells into the plasma Common themes are optimal, deficiency, or excess. Too much, too little, or just right!

Causes of Disturbances  A. normal output but deficient intake of absorption o Not nutrition, child being abused, nothing to drink, elderly people who don’t have a thirst mechanism  Increased output not balanced by increased intake o Diarrhea, vomiting and not replacing those fluid losses with Gatorade etc, pt on dialectics, athletics - profuse sweating but not replacing their fluid lost  B. Output less than excessive or too rapid intake o 2 rapid infusion of IV fluid  Decreased output not balanced by decreased intake o Chronic renal failure

Consequences of Disturbances:  Impaired Oxygenation and Perfusion o If I don’t have enough volume in blood stream, not enough oxygenated blood going aorunf the body, that’s nor perfusing well, theres not the amount there, I don’t have the oxygen that I need  Impaired Cerebral Function o Comes with cereberal swelling from cell swelling or cell shrinking o Sodium being off o Sometime the other electrolytes as well  Impaired Neuromuscular Function o Lot of electrlytes play parts in neuro muscular functions  Calcium, potassium, magnesium o If they off balance impaired neuro muscular function Fluid Disturbances (Fluid Shifts) Plasma to Interstitial Shift:  Causes: o increased capillary hydrostatic pressure  hydrostactic pressure is what pushes the fluid out of blood vessels and into interstitial space  hydrostactic pressure is influenced by BP and blood volume o decreased plasma proteins  If no pressure pulling the fluid back in from the interstitial spaces then decreased plasma in interstitial shift o increased capillary permeability  trauma pts, post-surgery, damage to the capillary membranes  Manifestations: o HR? BP? Urine Output?  Fluid volume going from plasma throughout the body into the interstitial spaces, where its just sitting there  BP decreases, Hr will increase, output is going to decrease to conserve fluid o Edema – where the fluid is going to sit  Periphery (legs, arms, sometimes stomach)  Tests – specific gravity, electrolytes, BUN, Creatinine, Hemoglobin, hematocrit, liver function (not the first thing to test)  Labs to Assess o Tests – specific gravity, electrolytes, BUN, Creatinine, Hemoglobin, hematocrit, liver function (not the first thing to test)  Collaborative Care: o F&E replacement cautiously  For this pt, replace fluid and electrolytes very cautiously, never want to correct a deficiency or excessive too quick because the body is constantly compensating by itself so if we intervene too quickly it can actually cause more of a problem o If Shock – emergency

 Shock is when ur BP drops, hypovolemic shock, not enough circulating blood volume Interstitial to Plasma Shift  Causes: o increased vascular plasma proteins  pulling that fluid in, increase in plasma protein, u can see the shift from interstitial to plasma  pt who’s recovering from burns, recovering from trauma o remobilization of fluid following burns or trauma o Pt has similar SS as someone who is excess IV isotonic infusion  Pt going to have edema, distended jungular veins, high BP,  Manifestations o edema o Distended jugular veins o SOB o High BP o Crackles in lungs  Labs to Assess? o specific gravity, electrolytes, BUN, Creatinine, Hemoglobin, hematocrit, weight of pt  Collaborative Care o Healthy heart and kidney: fluid is excreted naturally – body will do that on its own o If heart and kidney cannot handle fluid load… need to give diuretics and dialysis if super bad

Fluid-Spacing:  Used to describe the distribution of body water  First Spacing – normal distribution of ICF and ECF  Second Spacing – abnormal accumulation in interstitial space (edema)  Third Spacing – is trapped fluid and essentially unavailable. It is distributional shift of fluid in a space that is not easily exchanged with the ECF (i.e. peritonitis) o Trapped fluid in the hard to reach transcellular spaces, (peritoneal cavity, cerebral spinal fluid, synovial fluid)

ECV Deficit – Hypovolemia  Deficient Intake of Na+ & Water o Elderly who lost their thirst mechanism  Increased output not balanced by intake of water and Na+ o Vomiting, diarrhea and fluids are not being replaced  Fluid shifting (third spacing) o If no osmolality issues, then fluid shifting between the plasma and the interstitial spaces  Think about manifestations o Dehydration o Poor skin tugur o Dry mucous membrane  Labs o Specific gravity is HIGH o BUN and Creatinine = HIGH o Hemoglobin and hematocrit = HIGH  Less fluid and more cells o Electrolytes o Urine analysis ECV Excess – Hypervolemia  Output less than excessive or too rapid intake o IV fluid that goes in too fast o Someone who drinks and drink causing water intoxication  Decreased output not balanced by decreased intake of Na+ & water o Renal failure pt  Think about manifestations o SOB o Crackles in lungs o Extended jugular veins o Bounding pulses o High BP  Labs o Specific gravity o BUN and Creatinine o Hemoglobin and hematocrit o Electrolytes o Urine analysis

Hypernatremia = hyperosmolar  Osmolar = sodium o Sodium is what changes the osmolality  Results in cell-shrinking  Hyperosmolar situation = in the plasma, that’s where the blood is drawn o Cells are going to try to release fluid to try to help out the plasma  What manifestations would the nurse expect to find in this patient? o Hypovolemia o True classic dehydration o Poor skin tugur o Dry mucous membrane o Decrease urine output o BP might stay the same for a while then drop  Collaborative Care: o Restrict sodium intake o Isotonic or Hypotonic solution  Isotonic is preferred  because don’t want to correct the problem too quick if the body is trying to compensate and I add hypotonic, it can lead to over correcting  Only use hypotonic is my sodium is very high, and if my pt is symptomatic, neuro symptoms = big problems with sodium o Gradual lowering of sodium to prevent cerebral edema  Monitor changes in behavior or mental status o Because cells are shrinking o Seizurescoma o If pt has a change in consciousness = real problem, give the hypotonic solution o Can give D5W Hyponatremia – hypo-osmolar  Loss of Na+ o Cystic fibro...