Phys. of fluids electrolytes (7)

2,447 views

Published on

0 Comments
3 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
2,447
On SlideShare
0
From Embeds
0
Number of Embeds
6
Actions
Shares
0
Downloads
66
Comments
0
Likes
3
Embeds 0
No embeds

No notes for slide
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • Phys. of fluids electrolytes (7)

    1. 1. Physiology of Electrolytes Cindy McKinney, Ph.D. Block 2, 2012 Musculoskeletal System Supplemental Dr. Reilly
    2. 2. Learning ObjectivesElectrolytes Detail the normal concentrations of the following blood and cellular components Detail intracellular or extracellular location Sodium (Na+), Potassium (K+), Glucose, Calcium (Ca+2), Magnesium (Mg +2), Hydrogen ion (H+), Bicarbonate (HCO3-), Chloride (Cl-), Albumin,Creatinine and Urea State normal arteriole blood gases Interpret a normal urine dipstick and what the measures mean
    3. 3. Learning ObjectivesBone Marrow and Blood Components Describe production of RBCs –what tissues and what times produced State normal and abnormal Hematocrit (Hct) detail possible genetic, pathophysiological disturbances that lead to abn RBC production Define the normal range for each of the following and state what an abnorma elevated or abnormal value may indicate: -Hemoglobin -White Blood Cell (WBC) count -Red Blood Cell (RBC) count -White Blood Cell differential count -Platelet Count -Reticulocyte Count
    4. 4. Reading• Guyton Electrolytes
    5. 5. Body Fluid Spaces (TBW) Water is a major component of the fluid space (50-70% of body ICF ECF weight) Ultrafiltrate of plasma Plasma---without proteins and cells (RBCs) = 25% of ECFContained w/in cell=2/3of body water =1/3 body water Interstitial Fluid= 75% pf ECF ---baths the cells
    6. 6. Composition of body fluidsNot uniform between compartments---ICF and ECF have differentconcentrations ofof solutes one example: interstitial fluid being an ultrafiltrate of plasma containslittle proteinConcentrations of solutes can be expressed as: moles/L Eq/L Osm/LBecause biological concentrations are low you will usually see these values as: mmoles/L mEq/L mOsm/L
    7. 7. Composition of body fluidsRemember your high school chemistry:One mole=6 x 1023 molecules of solute; one millimole (mmole)= 1/1000mole=1 x 10-3 mole so: 1 mmol/L glucose =1 x 10-3 mole/L glucoseAn equivalent describes the amount of charged solute (Na+ ion as an example)in solution = number of moles of solute x its valence Examples: one mole of KCl in solution dissociates to one equivalent ofK+ and Cl- KCL K+ + Cl- one equivalent one mole of CaCl2 in solution dissociates in two equivalents of Ca andone Cl
    8. 8. Composition of body fluidsOne osmole is the number of particles from a solute in solutionOsmolarity measures the concentration of particles in solution osmoles/L(Note: a solute (like glucose) that does not dissociation in solution osmolarity = molarity)Examples: 1 mmol/L NaCl dissociates into two particles Na+ and Cl- osmolarity what is the osmolarity of a 1mmol/L solution of NaHCO3-?pH is used to express the H+ concentration in a body fluid= -Log10 [H+]Normally [H+] is very low  40 x 10-9 Eq/LBody pH is maintained in a narrow range of 7.35-7.45.
    9. 9. ElectroneutralityEach body fluid compartment obeys “principle of macroscopic neutrality”Thus: each compartment must have equal positive=negative charges for NO NET CHARGEEven if there is a potential difference between compartments-- balance isstill maintained within the compartment
    10. 10. Approximate Compositions of Solutes inthe ICF compared to ECF ICF ECF Solute Solute Concentration Concentration Na+ 14 Na+ 140 mEq/ mEq/L L K+ 120 K+ 4 mEq/ mEq/L L Ca+2 (ionized 1x Ca+2 2.5 mEq/ 10-4 mEq/L L Cl- 10 Cl- 105 mEq/ mEq/L L
    11. 11. Other solutes in solution Other solutes in cellular compartments Solute Concentration and Units Mg+2 0.9 mmol/L Albumin (protein) 4.5 g/dL Creatinine 1.2 mg/dL Urea (BUN) 12 mg/dL Glucose 80 mg/dL
    12. 12. SodiumMajor cation in ECF and vital mineral (electroneutrality balanced with HCO3= or Cl-)Most sodium found in blood or lymph fluid (85%)Sodium levels are controlled by kidney (hormone aldosterone)Small amount lost in sweatToo much sodium can raise blood pressure
    13. 13. PotassiumMajor cation of the ICF---electroneutrality balanced by anions (proteins andorganicphosphates like ATP, ADP, AMP)Necessary for proper functioning of heart, nerve fibers, muscles and GI tractMostly acquired via diet[K+]inside and [Na+]outside generate the membrane potential across a cellBalance between K+ and Na+ maintained by ion pumps and cell membrane
    14. 14. CalciumCalcium (Ca+2) is an important cation in biological systems; majoranions are HCO3-, PO4-3, SO4-signal transducer for hormone interactions (second messengersystems) andneurotransmitter release , muscle contraction, capacitationreaction (fertilization), bone formationBone is the main mineral storage reservoirIntracellular Ca+2 stores are in mitochondria and the endoplasmicreticulum
    15. 15. MagnesiumMagnesium (Mg+2) is an essential nutrient and present in every cell adult daily requirement=300-400 mg/dayMg+2-ATP is the biologically active form of ATP –Mg+2 facilitates activityMg+2 also plays a role in stability of DNA and RNA another PO4- compounds.Over 300 enzymes require the presence of Mg+2 for catalytic activity -all enzyme synthesizing or utilizing ATP -synthesis of DNA and RNABiological membranes are impermeable to Mg+ (can close certain types of Ca+2Hypomagnesemias—loss of balance due to muscle weakness; drug side effectHypermagnesemias---loss of kidney function (kidney excretes excess Mg quick
    16. 16. Bicarbonate (HCO3-) CO2 + H2O H2CO3 H+ + HCO3- (major blood buffering system) Carbonic Anhydrase (CA) Volatile AcidAcid-base Homeostasis (pH buffering)70-75% CO2 in body is converted to H2CO3 and then to HCO3- -protects tissues of the CNS where pH changes are disastrous - regulates pH in GI tractHCO3- standard concentration in blood at a CO2 =40 mm Hg, full O2 and 37C
    17. 17. Osmolarities are equal betweencompartmentsRemarkably—with all the concentration differences between the ICF and ECFtheosmolarities are equal this is due-- in part-- because water can flow freely across cellmembranes and between compartments water movement in and out balances the osmolarities in the twospaces flows from low concentration to higher concentration
    18. 18. Basic Metabolic Panel (BMP)Set of 7 (Chem-7) or 8 (Chem-8) chemical testsMonitors: electrolytes and fluid status kidney function  blood sugar levels  responses to medications
    19. 19. Chem-7 or Chem-8Four electrolytes: Sodium (Na+) Potassium (K+) Chloride (Cl-) Bicarbonate (HCO3- or pCO2)Blood urea nitrogen (BUN)CreatinineGlucoseCalcium (Ca+2) Chem-8
    20. 20. Fishbone Diagram of Chem-7 Na+ Cl- BUN Blood Glucose K+ HCO3-Creatinine Quick reference for common values
    21. 21. Comprehensive Metabolic PanelFourteen Blood tests:General: serum glucose Kidney FunctionAssessment calcium blood urea nitrogen creatinineProtein Tests: human serum albumin (HSA) total serum protein Liver FunctionAssessment Alkaline phosphatase (ALP)Electrolytes: Sodium (Na+) Alanine aminotransferase(ALT or SPGT) Potassium (K+) Aspartateaminotransferase (AST or SGOT)
    22. 22. Blood Urea Nitrogen (BUN)Liver produces urea in the urea cycle—waste product from digestion ofprotein -Normal value 7-21 mg/dL of bloodBUN value is an indicator of renal health if GFR and blood volume decrease (hypovalemia) then BUN willincrease
    23. 23. Lipid Panel• Total Cholesterol• High Density Lipoproteins (LDLs) cholesterol• Low Density Lipoprotein (LDLs) cholesterol• Very Low Density Lipoprotein (VLDLs)• Triglycerides
    24. 24. Urine Dipstick:
    25. 25. Urine Specific GravityUrine specific gravity—measures amount of solutes dissolved in urine compare Assessment of the kidney’s ability to concentrate or dilute urine directly proportional to urine osmolality (solute concentration) Normal value range: 1.002-1.035 if kidney function is normalDecreased <1.005 -inability to concentrate urine or excessive hydration (TBW expansion fr -nephrogenic diabetes insipidus, acute glomerulonephritis, acute tubul -falsely low sp.gr. can be associated with alkaline urine (pH>7.4) - after 12 fast w/o food and water, urine sp.grshuld be >1.022 if not—renal concentrating ability is impaired -nephrogenic diabetes insipidus or generalized renal issue
    26. 26. Urine Specific GravityFixed: 1.010 - the glomerular filtrate in Bowman’s Space ranges from 1.007-1.010 -measurements below tis range indicate hydration, above indicates relative dehydration -In End-Stage Renal Disease (ESRD) tends towards 1.010 -Chronic Renal failure, chronic glomerulonephritisIncreased: >1.035 -indicates a concentrated urine with a large volume of solutes -dehydration (fever, vomiting, diarrhea) SIADH, adrenal insufficiency, pre-renal renal failure, hyponatremia with edema, liver failure,nephrotic syndrome -elevation can also occur with glycosuria (diabetes or IV infusion)proteinuria
    27. 27. Urine pH (4.5-8.0)Kidneys –important role in acid-base regulation---maintain urine pH 5.5-6.5 -can vary between 4.5-8.0Glomerular filtrate is usually acidified in nephron tubules and collecting ducts froa pH equivalent to plasma (7.4) to a pH of 6 in final voided urinepH control is important in Bacteriuria, renal stones and drug therapyHigh Urinary pH (alkline urine)-vegetarian diet, low carbohydrate diet or ingestion of citrus fruit (alkali ash pro-systemic alkalosis (metabolic or respiratory)-renal tubular acidosis (RTA 1 distal), Fanconi anemia-urinary tract infections (urea splitiing organisms)-drugs (amphotercin B, CA inhibitors, salicylate OD
    28. 28. Urine pH (4.5-8.0)Low urinary pH (Acidic urine) - high protein diet or fruits like cranberries -systemic acidosis (metabolic or respiratory) -diabetes mellitus, starvation, diarrhea, malabsorption syndromes -PKU, alkaptouria, renal tuberculosis
    29. 29. ProteinNormal daily protein excretion should not exceed 150 mg/24 h or 10 mg/100mlProteinuria is production of >150 mg/day with nephritic syndrome =3.5 g/dayTrue protein evaluation:Renal- increased renal tubular secretion, increased GFR (glomerular disease),glomerular disease, nephrotic syndrome, malignant hypertensionFunctional proteinuria (albuminuria)- fever, cold exposure, stress,pregnancy, eclampsia, shock, severe exerciseOther- orthostatic proteinuria, electric current injury, hypokalemia, Cushing’s
    30. 30. Leukocytes (White Cell Counts)Determines presence of whole or lysed WBC in the urine (pyuria) bymeasuringleukocyte esterase activityPositive leukocyte esterase correlates well with pyuriaHOWEVER: diagnosis may be missed (in up to 20% cases) if a negativeurinalysis dipstikIs used to exclude UTIFalse Positive: contaminated specimen, trichomonas vaginalis, drugs orfoods that color the urine red (grape juice)False Negative: intercurrent or recent antibiotic therapy (gentamicin,
    31. 31. NitritesNitrates in the urine are converted to nitrites in the presence of gram-negative bacterialike E.coli and KlebsiellaA positive nitrites test is a surrogate marker for bacteria in urinePositive test strongly suggests infection (but does not exclude it)False negative: drugs or foods that color urine red
    32. 32. BloodDipstick is able to detect hemolyzed blood and non-lysed blood in urinePositive: may indicate hematuria from trauma, infection, inflammation, infa kidney stones, neoplasia, clotting disorders or chronic infectionHemaglobinuria: maybe associated with intravascular hemolysis, burns, su eclampsia, sickle cell crisis, multiple myeloma, alkaloids ( or transfusion reactions
    33. 33. KetonesKetones: (end-point of incomplete fat matabolism) accumulate in plasmaand are excreted in the urine ---acetoacetone, aceto-acidic acid, β-hydroxybuturateKetonuria is associated with low carbohydrate (high fat/protein) diets,stravation,Diabetes, alcoholism, eclampsia, and hyperthyroidismKetonuria is also associated with overdose of insulin, isonizid andisopropyl alcohol
    34. 34. GlucoseGlucose not normally present in urine (filtered but reabsorbed in proximaltubule) -<0.1% of glucose filtered appears in the urine (<130 mg/24h)Glycosuria occurs in patients with elevated glucose levels in the presenceof reducedthreshold and reduced glucose reabsorption (Tm exceeded) in renaldisese andPregnancyGlucosuoria also seen with certain drugs: cephalosporins, penicillins,methyl DOPA,steroids and thiazides
    35. 35. BilirubinBilirubin ( a product of liver function) can appear in the urine with liver diseasesand jaundice ---it may be seen before clinical signs developFormed by RBC degradation in the liver and then conjugated to glucuronide forexcretion inBile. In intestine converted to stercobilin –excreted in feces urobilinogen—excreted from kidneyFailure of bilirubin to reach the intestines (obstruction) will result in bilirubinuriaPositive test confirms conjugated hyperbilirubunaemiaRaised hyperbilirubinaemia with appearance in urine( bilirubinuria) ---heptacellular disease,Cirrhosis,viral or drug induced hepatitis, biliary tract obstruction, pancreaticinvolvement with
    36. 36. UrobilinogenNormally oresent in urine in low concentrations—0.2-1.0 mg/dL or <17μmole/LUrobilinogen is a product of bilirubin conversion by gut bacteria in theduodenum -excreted mostly in feces or transported back to liver for bileproduction -remaining is excreted in urine (<1%)Urobilinogen concentration increases in urine of patients with: cirrhosis,infectivehepatitis, extravascular hempysis, hemolytic anemia, pernicious anemia,malaria,
    37. 37. Key ConceptsIntracellular and extracellular ion concentrations are different extracellular: glucose, Na+. K+ HCO3- are a quick measure ofhomeostasisLipids: reveal diet and genetic make-upBUN and creatinine give you an estimate of renal functionUrine dipstick: can tell you about infection, liver and kidney function,diabetes mellitus orInspidus, metabolic state of the body (starvation changes)What are the different components of blood and a CBC panel?
    38. 38. Homework• Know the “normal” values of the majorICF and ECF anions and cations(Chem panel)

    ×