Norris11e_fluid electrolytes student-3.pptx

Trust in the Lord with all your heart and lean not on your own understanding. In all your ways acknowledge Him and He will direct your paths. Proverbs 3:5-6 Copyright © 2024 Wolters Kluwer. All rights reserved. Chapter 8 Disorders of Fluid,...

Trust in the Lord with all your heart and lean not on your own understanding. In all your ways acknowledge Him and He will direct your paths. Proverbs 3:5-6 Copyright © 2024 Wolters Kluwer. All rights reserved. Chapter 8 Disorders of Fluid, Electrolyt e , and Acid–Base Balance Functions of Body Fluids Transport gases, nutrients, and wastes Help generate the electrical activity needed to power body functions Take part in the transformation of food into energy Maintain the overall function of the body Copyright © 2025 Wolters Kluwer. All rights reserved. 5  Intracellular Compartment Distribution of (ICF) Body Fluids oConsists of fluid contained within all of the billions of cells in the body oLarger of the two compartments, with approximately two thirds of the body water in healthy adults oHigh concentration of K+ Extracellular Compartment (ECF) oContains the remaining one third of body water oContains all the fluids outside the cells, including that in the interstitial or tissue spaces and blood vessels oHigh concentration of Na+ Copyright © 2025 Wolters Kluwer. All rights reserved. 6 Composition of the Extracellular Fluid S Large amounts of sodium and chloride C C Moderate amounts of bicarbonate Small quantities of potassium, magnesium, calcium, and phosphorus Copyright © 2025 Wolters Kluwer. All rights reserved. Composition of the ICF Almost no calcium PP Small amounts of sodium, chloride, M bicarbonate, and phosphorus Moderate amounts of magnesium Large amounts of potassium Copyright © 2025 Wolters Kluwer. All rights reserved. Memory Aids S Na P C K C P M Na K pump Copyright © 2025 Wolters Kluwer. All rights reserved. Question #1 Which ion is in the highest concentration in the ICF? A. Na+ B. K+ C. Cl− D. Ca2+ Copyright © 2025 Wolters Kluwer. All rights reserved. 10 Diffusion and Concentration Gradient Osmosis oDifference in concentration over a distance Diffusion oThe movement of charged or uncharged particles along a concentration gradient from an area of higher concentration to one of lower concentration Osmosis oThe movement of water across a semipermeable membrane from the side of the membrane with the lesser number of particles and greater concentration of water to the side with the greater number of particles and lesser concentration of water Copyright © 2025 Wolters Kluwer. All rights reserved. 11 Tonicity & concentration gradients Diffusion – solute flows.......... from higher concentration to lower. concentration Solute = Osmosis – semi-.. permeable membrane allows solvent to flow...... Solvent =.. Copyright © 2024 Wolters Kluwer. All rights reserved. Tonicity The tension or effect that the effective osmotic pressure of a solution with Solutions can be impermeable solutes exerts on cell size classified according because of water movement across the cell to whether or not membrane they cause cells to shrink: oIsotonic: neither shrink nor swell oHypotonic: swell oHypertonic: shrink Copyright © 2025 Wolters Kluwer. All rights reserved. 13 Clinical examples water NaCl sugar Copyright © 2024 Wolters Kluwer. All rights reserved. IV Solutions hypotonic isotonic hypertonic 0.25% NaCl 0.9% NaCl (normal saline) D5 NaCl 0.45% NaCl Lactated Ringer’s solution D5 LR (LR) 2.5% dextrose D5W (acts hypotonic in the D5 0.45% NaCl body) Copyright © 2024 Wolters Kluwer. All rights reserved. Where do the fluids shift?. #1 #2 TISSUE........ S...... RBC.. BLOO BLOO D D VESS Copyright © 2024 Wolters Kluwer. All rights reserved. VESS Edema 3rd spacing Accumulation of Loss or trapping of ECF in fluid in transcellular space extracellular space oPericardial sac oPeritoneal cavity oPitting edema oPleural cavity oNonpitting edema Contributes to body weight but not fluid reserve or function Caused by oLeaky capillary syndrome (pancreatitis) oHypoalbuminemia (liver failure) oIntestinal obstruction oCrush injuries Copyright © 2025 Wolters Kluwer. All rights reserved. 18 oBurns Edema Formation The physiologic mechanisms that Fluid can be contribute to edema: pressured, oIncrease the pulled, leaked, or capillary filtration blocked (from pressure being drained) oDecrease the capillary colloidal osmotic pressure oIncrease capillary permeability oProduce obstruction to lymph flow Copyright © 2024 Wolters Kluwer. All rights reserved. Body water Copyright © 2024 Wolters Kluwer. All rights reserved. Methods for Physiologic Assessing Edema Mechanisms Assisting in Daily weight Regulating Body Thirst Visual Water oPrimarily a regulator of assessment water intake Measurement of ADH the affected part oA regulator of water Application of output finger pressure to Both mechanisms respond assess for pitting to changes in extracellular edema osmolality and volume Copyright © 2025 Wolters Kluwer. All rights reserved. 21 Hypodipsia Polydipsia Lesions in hypothalamus 1) Symptomatic/true thirst oHead trauma - Resolves when replaced oMeningiomas - Occurs w/ vomiting, diarrhea, DM, DI oOccult hydrocephalus oSubarachnoid hemorrhage 2) False thirst despite normal levels of Decreased thirst body water and osmolality o>80 years old - from increased angiotensin (CHF, DM, CKD), or anticholinergic drugs ↓Perception oStroke oConfusion 3) compulsive water drinking - schizophrenia, antipsychotic meds oSensory deficits oMotor disturbances - cigarette smoking (stimulates ADH) Copyright © 2025 Wolters Kluwer. All rights reserved. 22 Water and Na+ Baroreceptors Gain Balance regulate effective Water volume. Oral intake and Modulating metabolism of nutrients sympathetic Na+ nervous system outflow and ADH Loss secretion Kidneys ANP Skin RAAS Lungs le Angiotensin II ins e ns i b Gastrointestinal Aldosterone tract Copyright © 2025 Wolters Kluwer. All rights reserved. 23 RAAS Adriana RN ACE Aldoster(n)one Angiotensinoge acne n Sydney II SN raise in stress level 2 (kidney) “rent” RENIN B/P Angiotensinoge nI Arthur stress level 1 RN artery Angiotensinoge vasoconstrictio n Regulators of The kidney is the main regulator of sodium. Sodium oMonitors arterial pressure retains sodium when arterial pressure is decreased eliminates it when arterial pressure is increased oThe rate is coordinated by the sympathetic nervous system and the renin–angiotensin– aldosterone system (RAAS). oAtrial natriuretic peptide (ANP) may also regulate sodium excretion by the kidney. Copyright © 2025 Wolters Kluwer. All rights reserved. 25 Disorders of ADH Expression Diabetes insipidus Syndrome of inappropriate Too M oUnable to concentrate antidiuretic hormone u (SIADH) ch urine during periods of water restriction, leading – Failure of the negative to excretion of large feedback system that volumes of urine regulates the release and inhibition of ADH oDeficiency of or a decreased response to ADH To o Lit t le Nephrogenic Neurogenic/central Kidneys don’t Defect in synthesis or respond to ADH release of ADH Copyright © 2024 Wolters Kluwer. All rights reserved. Assessment of History of conditions that predispose to Body Fluid Loss sodium and water losses, weight loss, and observations of altered physiologic function indicative of decreased fluid volume oHeart rate oBlood pressure oVenous volume/filling oCapillary refill rate Copyright © 2025 Wolters Kluwer. All rights reserved. 27  Isotonic Fluid Volume Excess Fluid Volume Excessive fluid intake Deficit Inadequate intake (related to output) GI loss Excessive sodium Renal loss intake (related to Skin loss output) 3rd spacing Inadequate elimination Renal function Heart failure Liver failure Corticosteroid excess Copyright © 2025 Wolters Kluwer. All rights reserved. Potassium Intracellular concentration of 140 to 150 Distribution and mEq/L Regulation The extracellular concentration of 3.5 to 5.0 mEq/L Body stores of potassium are related to body size and muscle mass. Is normally derived from dietary sources Plasma potassium is regulated through two mechanisms: oRenal mechanisms that conserve or eliminate potassium oA transcellular shift between the ICF and ICF compartments Copyright © 2025 Wolters Kluwer. All rights reserved. 31 Abnormal Hypokalemia refers to a decrease in plasma Potassium potassium levels below 3.5 mEq/L 1. Inadequate intake 2. Excessive gastrointestinal, renal, and skin losses 3. Redistribution between the ICF and ECF compartments Hyperkalemia refers to an increase in plasma levels of potassium in excess of 5.0 mEq/L 1. Decreased renal elimination 2. Excessively rapid administration 3. Movement of potassium from the ICF to ECF compartment Copyright © 2025 Wolters Kluwer. All rights reserved. 32 Diagnosis and Diagnosis Treatment of obased on complete history, physical Potassium examination to detect muscle weakness and Disorders signs of volume depletion, plasma potassium levels, and ECG findings. Treatment oCalcium antagonizes the potassium-induced decrease in membrane excitability. oSodium bicarbonate will cause K + to move ICF. oInsulin will decrease ECF K+ concentration. oCurtailing intake or absorption, increasing renal excretion, and increasing cellular uptake Copyright © 2025 Wolters Kluwer. All rights reserved. 33 Hypokalemia symptoms S – skeletal muscle weakness U – U wave prominent C - constipation T – toxic effect of digoxin I– irregular, weak pulse O – orthostatic hypotension N – numbness (parasthesia) When kidneys fail acid prevails Calcium, Calcium, phosphate, and magnesium are the Phosphate and major divalent cations in the body. Magnesium Balance They are oIngested in the diet oAbsorbed from the intestine oFiltered in the glomerulus of the kidney oReabsorbed in the renal tubules oEliminated in the urine Copyright © 2025 Wolters Kluwer. All rights reserved. 35 Calcium balance Calcium gains Losses Dietary dairy foods When dietary intake (and calcium PTH and vitamin D absorption) is less stimulate calcium than intestinal reabsorption in this secretion segment of the nephron. Calcitonin acts on the kidney and bone to remove calcium from the extracellular circulation. Copyright © 2025 Wolters Kluwer. All rights reserved. 36  Ca: 8.5 – 10.5 Hypocalcemia mg/dL Hypercalcemia ↓ ability to mobilize Ca from Increased intestinal bone hypoparathyroidism absorption Excessive vitamin D and ↓ intake/absorption calcium Vit D deficiency Milk-alkali syndrome Abnormal losses of Ca (via Increased bone resorption phosphorus retention in CKD)  Parathyroid hormone Increased protein Malignant neoplasms Prolonged immobilization binding/chelation Soft tissue sequestration Decreased elimination pancreatitis Thiazide, lithium therapy Tx: IV Ca gluconate or Tx: Fluid replacement chloride (NaCl), Copyright © 2025 Wolters Kluwer. All rights reserved. 37 Calcium symptom comparison Question #2 Alterations in __________ may result in hypercalcemia. A. ADH B. Na+ C. vitamin D D. K+ Copyright © 2025 Wolters Kluwer. All rights reserved. 39 Role of Phosphate Plays a major role in bone formation Essential to certain metabolic processes: -The formation of ATP and the enzymes needed for metabolism of glucose, fat, and protein A necessary component of several vital parts of the cell Incorporated into the nucleic acids of DNA and RNA and the phospholipids of the cell membrane Ph Serves as an acid–base buffer in the extracellular fluid and in the renal excretion of hydrogen ions Necessary for delivery of oxygen by the red blood cells Ca Needed for normal function of other blood cells Copyright © 2025 Wolters Kluwer. All rights reserved. 40 -White blood cells and platelets Acid–Base Physiological pH-7.35-7.45 carbon dioxide CO2 + H2O H2CO3 H+ + HCO3- carbonic acid Copyright © 2025 Wolters Kluwer. All rights reserved. 45 Regulation of pH Compensatory mechanisms maintain ECF pH The concentration of metabolic Laboratory Tests acids and bicarbonate Arterial blood base is regulated gases and pH by the kidney. Carbon dioxide and The concentration bicarbonate levels of CO2 is Base excess or regulated by the deficit respiratory Anion gap system. Copyright © 2025 Wolters Kluwer. All rights reserved. 46 Breathing in and out CO2 CO2 r. acidosis CO2 r. alkalosis Respiratory Acidosis R. acidosis reflects an increase in PCO2 levels and is caused by conditions that impair alveolar ventilation. oImpaired function of the respiratory center in the medulla (as in narcotic overdose) oLung disease oChest injury oWeakness of the respiratory muscles oAirway obstruction ↓ pH ↑ pCO2 (>45) Copyright © 2025 Wolters Kluwer. All rights reserved. 48 Respiratory Alkalosis R. alkalosis is caused by conditions that cause hyperventilation and a reduction in PCO2 levels. oAnxiety and psychogenic hyperventilation oHypoxia and reflex stimulation of ventilation oLung disease that reflexively stimulates ventilation oStimulation of respiratory center ↑ pH oMechanical ventilation ↓ pCO2 ( 45 hyperventilation – r. < 35 alkalosis HCO3 metabolic acidosis (LGI < 22 (22) loss) metabolic > 28 alkalosis (UGI loss) (26) Condition Primary etiology Contributing etiology respiratory hypoventilation COPD, pulm dz, drugs, acidosis chest injury, obesity, sleep apnea, paralytic drugs metabolic Addition of lrg amts Lactic acidosis (resp acidosis acids to body failure), ketoacidosis (diabetes, alcoholic, starvation), salicylate poisoning respiratory hyperventilation Overventilation from: alkalosis anxiety/ panic, lung dz, fever, vent settings, ↑ammonia, ↑altitudes metabolic Retention of base Excess gastric drainage, alkalosis or removal of acid vomiting, K deficit, Milk- alkali syndrome, diuretics How to interpret ABG values  #1 Determine the pH  #3 Determine HCO3 (metabolic) (acidic or alkaline) HCO3 < 22 is m. acidosis pH < 7.35 is acidic HCO3 > 28 is m. alkalosis pH > 7.45 is basic  #4 Which one explains the pH  #2 Determine pCO2 state? (respiratory) If pH normal (and CO2 or HCO3 CO2 < 35 is r. alkalosis abnormal) = compensated CO2 > 45 is r. acidosis If pH abnormal & both CO2 & HCO3 abnormal= partially Copyright © 2024 Wolters Kluwer. All rights reserved. ABG Analysis 1 ______________________________  pH 7.35-7.45 7.35 WDL  pCO2 35-45 42 WDL  HCO3 22-28 26 WDL  ABG Analysis 1 Interpretation:  pH 7.35 Normal Cause:  PCO2 42 NA Treatment:  HCO3 26 None  compensated? ABG Analysis 2 __________________________________ NO  pH 7.35-7.45 7.31 acidosis  pCO2 35-45 52 ↑ acid = r. acidosis  HCO3 22-28 27 WDL  ABG Analysis 2 Interpretation: uncompensated respiratory acidosis  pH 7.31 Cause: hypoventilation  PCO2 52 Treatment: mechanical ventilation  HCO3 27 - rate &/or tidal volume  compensated? ABG Analysis 3 ___________________________________ NO  pH 7.35-7.45 7.29 acidosis  pCO2 35-45 40 WDL  HCO3 22-28 21 base = m. acidosis  ABG Analysis 3 Interpretation: Uncompensated metabolic When kidneys fail acidosis acid prevails Cause:  pH 7.29 Ketoacidosis; lactic acidosis; renal failure; diarrhea  PCO2 40 Treatment: Treat underlying cause  HCO3 21 Administer sodium bicarbonate  compensated? ABG Analysis 4 ___________________________________ partially  pH 7.35-7.45 7.47 alkalosis  pCO2 35-45 46 ↑ acid = r. acidosis Which one explains pH?  HCO3 22-28 30 ↑ base = m. alkalosis  ABG Analysis 4 Interpretation: Partially compensated metabolic alkalosis Cause:  pH 7.47 UGI loss, diuretic therapy, steroid therapy, hypokalemia  PCO2 46 Treatment: Evaluate drug therapy & suction  HCO3 30 Supplement K+ ABG Analysis 5 ___________________________________  pH 7.35-7.45 7.36 WDL  pCO2 35-45 50 ↑ acid = r. acidosis Which one explains pH?  HCO3 22-28 35 ↑ base = m. alkalosis One more rule 7.35-7.45 pH in the acid range of normal 7.35-7.40 pH in the alkaline range of normal 7.41-7.45 Therefore, choose the explanation that fits the number Evaluation pH pCO2 HCO3 Compensated respiratory 7.35- >45 >28 acidosis 7.40 Compensated respiratory 7.41-