4Fluid Balance (cont)Homeostasis- Dependent on fluid and electrolyte intake physiologic factors, disease state factors, external environmental factors and pharmacologic intervention.Intracellular fluid (ICF) water in the cells = 40%Extractracellular fluid (ECF) fluid out side the cells = 20%15% in tissue space (interstitial) outside the blood vessel, between cells5% in plasma (intravascular space)
6Fluid Balance Normal intake 1-3 L/day 200-300 ml produced by oxidation Normal intake and output will balance approximately every 72 hours
7Fluid Balance Elimination of fluids is considered Sensible (measurable) lossSkin, Kidneys, Bowels, lungs lose fluidml lost through lungs every 24 hrs.500ml lost with perspirationInsensible (not measurable) lossConsidered to be ml/dayLost through GI tract only ml/day
8Fluid Balance (cont) Loss from Diarrhea or intestinal fistula Significant sweat loss when body temp >101F-38.3C or room temp > 90FWhen respirations > 20/minFormula to calculate insensible lossml/m2/day
9Fluid Function The fluid in the body has the following function: Maintains blood volumeRegulates body temperatureTransports material to and from cellsServes as an aqueous medium for cellular metabloismAssists digestion of food through hydrolysisActs as a solvent in which solutes are available for cell functionServes as a medium for the excretion of waste
10Fluid Transport 4 transport mechanisms Passive transport Passive diffusion-OsmosisFiltrationActive transport
11Fluid TransportPassive transport- non carrier mediated transport- Fluid moves through membranes with out the expenditure of energyPassive diffusion - movement of water and other elements in all directions from high concentration to low concentrationOsmosis – passage of water from low particle concentration toward one of higher particle concentrationNormal osmolarity – mOsm/LOsmolarity of ICF and ECF is always equal
12Fluid Transport (cont) Filtration – the transfer of water and a dissolved substance from a region of high pressure to a region of low pressure. Force behind it is hydrostatic pressure (the pressure of water at rest)Pumping heat provides hydrostatic pressure in the movement of water and electrolytes from the arterial capillary bed to the interstitial fluid.
13Fluid Transport (cont) Plasma protein creates and osmotic pressure at the capillary membrane, preventing fluid from plasma leaking into interstitial spacesOsmotic pressure (created within the plasma) keeps water in the vascular system
14Fluid Transport (cont) Starling’s law of capillariesUnder normal circumstances fluid filtered out of the arterial end of a capillary bed and reabsorbed at the venous end is exactly the same, creating a state of near equilibrium
15Fluid Transport (cont) Active Transport – acts as a concentration gradientATP – released from the cell to enable substances to acquire the energy needed to pass through the cell membraneActive Transport is vital for maintaining the unique composition of both the intracellular and intracellular compartments
16Tonicity of Solution Isotonic - .9% saline, 5% dextrose same as body fluidsOsmolarity of mOsm/LRemains within the ECF spaceUsed to expand ECF compartment
20Tonicity of SolutionHypertonic – causes water from within a cell to move to the ECF compartmentOsmolarity of 375mOsm/l or greaterUsed to replace electrolytesUsed to shift EDF from interstitial tissue to plasmaD5W, .9 Normal Saline
22Homeostatic Mechanism Regulation of body water is maintainedExogenous sources - Intake of food & Fluids (nurse’s responsibility)Endogenous sources – produce with in the body through chemical exidation process (various body systems responsible)
23Homeostatic Mechanisms Renal System – Kidneys filter 170L l of plasma/day and excrete 1.5L of urineRegulation of fluid volume and osmolarity by selective retention and secretion of body fluidRegulation of electrolyte levels by selective retention of needed substances and excretion of unneeded substancesRegulation of pH of ECF by excretion or retention of hydrogen ionsExcretion of metabolic wastes (primarily acids) and toxic substances
24Homeostatic Mechanism Cardiovascular System –Pumping action of the heart provides circulation of blood through the kidneys under pressureAllow urine to formRenal perfusion makes renal function possible
25Homeostatic Mechanism Lymphatic system –Serves as an adjunct to the cardio vascular system by removing excess interstitial fluid (lymph) and returning it to the circulatory systemPrevents fluid overload
26Homeostatic Mechanism Respiratory SystemLungs are vital for maintaining homeostasis and constitute one of the main regulatory orgnas of fluid and acid base balanceFunctions of the lungsRegulation of metabolic alkalosis by compensatory hypoventilationRegulation of metabolic acidosis by causing compensatory hyperventilationRemoval of ml of water daily through exhalation
27Homeostatic Mechanism Nervous systemMaster controller in fluid and electrolyte balance through the regulation of sodium and waterEndocrine systemResponsible for aiding homeostasis through production of various hormonesAntidiuretic hormones (ADH)Parathyroid HormonesAldosteroneEpinephrine
28Physical AssessmentVital signs, infusion rate of IV fluids, intake and output.Neurological - Changes in orientation, irritability, lethargy, confusion, seizures or comaCardiovascular –Quality and rate of pulsePeripheral vein fillingOrthostatic hypertensionDistended or Flat neck veins
31Physical Assessment Skin Appearance & Temperature Access skin turgor Appearance of the tongue
32Physical Assessment Body Weight Weigh Daily – better indicator than I&O recordsLoss or gain of 1 kg indicates a loss or gain of 1 L of body fluid15% flucation is considered sever
33Fluid Volume Imbalance Fluid Volume DeficitCommon Causes of Isotonic DehydrationHemorrhage resulting in loss of fluid, electrolytes, proteins and blood cells resulting in inadequate vascular volumeGastrointestinal lossesFever, environmental heat, profuse sweatingBurnsDiureticsThird spaced fluids
34Fluid Volume Imbalance Causes of Hypertonic Fluid DehydrationInadequate fluid intakeDecreased water intake results in ECF solute concentration and leads to cellular dehydration
35Fluid Volume Imbalance Fluid Volume ExcessPrimary cause – Cardiovascular dysfunction secondary to an increase in total body sodium contentCauses of isotonic over hydrationRenal failure leading to decrease excretion of water and sodiumHeart failure leading to stasis of bloodExcess fluid intake of isotonic IV solutionHigh corticosteroid levelsHigh Aldosterone levels
36Fluid Volume Imbalance Common causes of Hypotonic Over hydration (Water intoxication)More fluid is gained than soluteSerum osmolality falls causing cells to swellRepeated water enemasOveruse of hypotonic IV fluidsIngestion of inappropriately prepared formulaSIADH causes kidneys to retain large amounts of water without sodiumTreatment- sodium and fluid restriction, diuretics, treat underlying cause.
37Electrolyte BalanceMajor electrolytes in body fluid are sodium, potassium, calcium, magnesium, chloride, phosphorus and bicarbExpressed in meq/liter. Measures chemical activity or combining power rather than weightEach water compartment of the body contains electrolytesConcentration and composition vary from compartment to compartment
38Electrolyte Balance (cont) Physiological role of electrolytesMaintaining electroneutrality in fluid compartmentsMediating enzyme reactionsAltering cell membrane permeabilityRegulating muscle contraction and relaxationRegulating nerve impulse transmissionInfluencing blood clotting time
39Electrolyte Balance (cont) Sodium mEq/LPhysiologic role of sodium:Regulation of fluid distribution in body: water follows sodiumMaintenance of body fluid osmolarityPromotion of neuromuscular response: Transmission of nerve and muscle impulses depends on sodium, gradient between ECF and ICFRegulation of acid-base balance: Sodium combines with chloride and bicarbonate to alter pH
40Electrolyte Balance (cont) Sodium represents 90% of the extracellular cationsSerum plasma levels of electrolytes are important in the assessment and management of patients with electrolyte imbalancesNormal daily requirement 100mEqHyponatermia is a common complication of adrenal insufficiencyHypernatermia – Serum Sodium excess great that 145mEq/L can occur with deprivation of water
41Electrolyte Balance (cont) Signs and Symptoms - Marked thirst, elevated body temperature, swollen tongue.Chronic Hyponatremia: impaired sensation of taste, anorexia, muscle cramps, feeling of exhaustion, apprehension, feeling of impending doom and focal weakness.Treatment: Gradually lower seum sodium level by infusion of hypotonic electrolyte solution .45 Normal Saline or D5W. Level lowered no more than 15 mEq/L in 8 hr.
42Electrolyte Balance (cont) Potassium: Physiological roleRegulation of fluid volume within the cellPromotion of nerve impulse transmissionContraction of skeletal smooth and cardiac muscleControl of hydrogen ion concentration, acid-base balanceRole of enzyme action for cellular energy production.
43Electrolyte Balance (cont) Potassium is an intracellular electrolyte with 98% in ICF and 2% in the ECFAcquired thru diet and must be ingested dailyDaily requirement is 40 mEqInvolved in muscle activity and transmission of nerve impulses.
44Electrolyte Balance (cont) Hypokalemia (cont) – Can cause alkalosisS&S fatigue, muscle weakness, anorexia, nausea and vomiting, irregularityTreatment – at level less than 3.5mEq/L replacement must be slow to prevent hyperkalemia
45Electrolyte Balance (cont) Hyperkalemia- Serum plasma level greater than 5.5mEq/LIncreased intake of potassiumDecreased urinary excretionMovement out of cells into extra cellular space.Signs & SymptomsChanges shown on ECGVague muscle weaknessFlaccid paralysisAnxietyNausea and vomitingCramping and diaherrea
46Electrolyte Balance (cont) Calcium: Physiological roleMaintaining skeletal elements; calcium is needed for strong bones and teethRegulating neuromuscular activityInfluencing enzyme activityConverting prothrombin to thrombin, a necessary part of clotting.99% resides in bones and teeth
47Electrolyte Balance (cont) Hypocalcemia: reduction in total body calcium levelsBecause of increase calcium loss, reduced intake secondary to altered intestinal absorption, altered regulation hypoparathyroidismS & S:Numbness of fingers, muscle cramps, hyperactive deep tendon reflexes, positive Trousseaus’s sign and Chevostek’s signTreatment with Calcium Gluconate oral or IV
48Electrolyte Balance (cont) Hyperclacemia: Excessive release of calcium from boneS & S Neuromuscular symptoms, lethargy, bone pain, flank pain, pathological fractures, constipation, anorexia, N & V, Stone formation.
49Electrolyte Balance (cont) Magnesium: Physiological roleEnzyme actionRegulation of neuromuscular activityRegulation of electrolyte balance, including facilitating transport of sodium and potassium across cell membranes, influencing the utilization of calcium, potassium, and protein.A major intracellular electrolyte
50Electrolyte Balance (cont) Hypomagnesemia: often overlooked in critically ill patientsResults from:Chronic alcoholismMalabsorption syndromeProlonged malnutrition or starvationProlonged diarrheaAcute pancreatitisAdministration of magnesium-free solutions for more than one weekProlonged NG tube suctioning
51Electrolyte Balance (cont) S & SNeuromuscular symptomsHyperactive reflexes,Coarse tremorsMuscle crampsPositive Chvostek’s and Trousseau’s signsSeizuresParesthesia of the feet and legsPainfully cold hands and feetDisorientation dysrhythmias tachycardia and indreased potential for digitalis toxicity
52Electrolyte Balance (cont) Hypermagnesemia: renal failure, addison’s disease, and inadequate excretion of magnesium by kidneysS & S:Neuromuscular symptomsFlushing and sense of skin warmthLethargySedationHypoactive deep tendon reflexes,Depressed respirationWeak or absent new born cry
53Electrolyte Balance (cont) Phosphorus: physiologic role:Essential to all cellsRole in metabolism of proteins, carbohydrates and fatsEssential to energy, necessary in the formation of high energy compounds adenosine triphosphate (ATP) and adenosine diphosphate (ADP)As a cellular building block, it is the backbone of nucleic acids and is essential to cell membrane formation’Delivery of oxygen; functions information of red blood cell enzyme.
54Electrolyte Balance (cont) Approximately 80% is contained in the bones and teeth20% is abundant in the ICFPlays and important role in delivery of oxygen to tissues by regulating the level of 2,3-DPGHyphphosphatemia: results fromOverzealous refeeding,TPN administered without adequate phosphorusMalabsorptionAlcohol withdrawalVomiting, chronic diarrhea, and malabsorption syndromes
55Electrolyte Balance (cont) Other Electrolyte imbalance:HyperphosphatemiaHypochloremiaHyperchloremia