This document discusses fluid compartments and electrolytes. It notes that total body water varies with age, gender, and body fat percentage. Intracellular fluid makes up 60% of body fluid and is rich in potassium and magnesium, while extracellular fluid is 40% and contains more sodium, chloride, and bicarbonate. Fluid compartments are regulated by membranes and pressures. Fluid balance is maintained through neutral, positive, or negative balances. The kidneys, lungs, heart, and hormones like aldosterone and ADH help regulate fluids and electrolytes. Disturbances can cause problems like volume depletion, overload, or specific electrolyte disorders.

1. 10/5/20090FLUIDS AND ELECTROLYTESDr. Tanuj Paul BhatiaMBBS,MS

2. Fluid compartments10/5/20091

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4. Total body water varies with…AgeGenderBody fat (Fat contains less water)10/5/20093

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6. Intracellular fluid60% of body fluidRich in :PotassiumMagnesiumproteins10/5/20095

7. Extracellular fluid40 % of body fluidRich in :SodiumChlorideBicarbonate Interstitial fluid : between cells, low in proteinIntravascular fluid(Plasma) : High in proteinTranscellular fluids – CSF, intraocular fluids, serous membranes (third space)10/5/20096

8. Spacing First space: normal Second Space: interstitial - edema; Third Space: in places not normally found 10/5/20097

9. Fluid compartments are separated by membranes that are freely permeable to water.Movement of fluids due to: Hydrostatic pressure Osmotic pressure Examples:Capillary filtration (hydrostatic) pressureCapillary colloid osmotic pressureInterstitial hydrostatic pressureTissue colloid osmotic pressure10/5/20098

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11. Fluid balance10/5/200910Total for both is 2550ml

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13. BalanceFluid and electrolyte homeostasis is maintained in the bodyNeutral balance: input = outputPositive balance: input > outputNegative balance: input < output10/5/200912

14. Regulators: organs & hormonesKidneys: regulates fluid volume, electrolytes, pH, waste; influenced by ADH & aldosteroneLungs: remove 500 cc fluid. Heart & blood vessels: regulate pressure. 10/5/200913

15. Aldosterone: REGULATES SODIUM and potassium balance. INCREASED ALDOSTERONE TO RETAIN SODIUM & excrete potassium in kidneys. ADH - CONTROLS WATER. ADH release causes kidney tubules to retain water 10/5/200914

16. Solutes – dissolved particlesElectrolytes – charged particlesCations – positively charged ionsNa+, K+ , Ca++, H+Anions – negatively charged ionsCl-, HCO3- , PO43-Non-electrolytes - Uncharged Proteins, urea, glucose, O2, CO210/5/200915

17. MW (Molecular Weight) = sum of the weights of atoms in a moleculemEq (milliequivalents) = MW (in mg)/ valencemOsm (milliosmoles) = number of particles in a solution10/5/200916

18. Solutes determine the tonicity of a solution10/5/200917

19. tonicity10/5/200918

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21. 20Cell in a hypertonic solution

22. 21Cell in a hypotonic solution

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24. 23 Movement of body fluids “ Where sodium goes, water follows.”Diffusion – movement of particles down a concentration gradient.Osmosis – diffusion of water across a selectively permeable membraneActive transport – movement of particles up a concentration gradient ; requires energy

25. Regulation of body waterADH – antidiuretic hormone + thirstDecreased amount of water in bodyIncreased amount of Na+ in the bodyIncreased blood osmolalityDecreased circulating blood volumeStimulate osmoreceptors in hypothalamusADH released from posterior pituitaryIncreased thirst24

26. 25Result: increased water consumption increased water conservation Increased water in body, increased volume and decreased Na+ concentration

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28. Different components of renal function occur along thenephron. A normal glomerular filtration rate of 125 mL/minwould generate 180 L/day of filtrate containing 27,000 mmolofsodium. 10/5/200927

29. Approximately two thirds of the filtered sodium is absorbed in the PCT, 20% in the LOH, 7% in the DCT, and 3%in the CD; the net excretion of urinary sodium per day, as a fraction of the total sodium filtered load, is less than 1%.10/5/200928

30. Disturbances of fluid and electrolyte balance10/5/200929

31. Volume depletionPure volume deficits – RARECauses : 1. Comatosed patients with increased insensible loss (e.g. fever) 2. Diabetes insipdusReflected biochemicalyby hypernatremia.10/5/200930

32. Clinical featuresDue to depressed nervous systemLethargyMuscle rigiditySeizuresComa 10/5/200931

33. Treatment Replacement of adequate water by 5% Dextrose10/5/200932

34. Volume and electrolyte depletionDue to extrarenal loss of body fluid Causes : VomitingDiarrohoeaNasogastric suctionIntestinal fistulaeIntestinal obstructionPeritonitis10/5/200933

35. Effects 10/5/200934

36. Effects 10/5/200935

37. Clinical featuresSunken eyesTongue – Dry and CoatedLow urinary outputLab: Normal or Slightly reduced Serum SodiumLow urinary sodium10/5/200936

38. Treatment Replacement of sodium deficit in addition to volume deficit by infusion ofIsotonic saline, orRinger’s lactateDepending on the severity of hyponatremia10/5/200937

39. Volume overloadConservation of sodium and water following stress like surgeryIf fluid intake is excessive in immediate post op  fluid overload may occur.10/5/200938

40. Tendency of fluid overload increases in patients with :Heart diseaseLiver diseaseKidney disease10/5/200939

41. Clinical featuresPeripheral edemaJugular venous distensionTachypnoea ( due to pulmonary edema)10/5/200940

42. Treatment Mild overload:Restriction of sodium and waterSevere overload : Diuretics 10/5/200941

43. Specific electrolyte disorders10/5/200942

44. HyponatremiaAlways associated with volume depletionClinical features and treatment as discussed before10/5/200943

45. HypernatremiaSerum Na levels > 150Mmol/lCauses:Renal dysfunctionCardiac failureDrug induced (NSAIDS, corticosteroids)10/5/200944

46. Types of hypernatremiaEuvolemic (pure water loss)Hypovolemic (more water lost than sodium)Hypervolemic (both gained but more sodium gained)10/5/200945

47. Clinical featuresPitting edemaPuffiness of faceIncreased urinationDilated jugular veinsFeatures of pulmonary edema10/5/200946

48. Treatment Restriction of sodium and saline.Treatment of pulmonary edema.10/5/200947

49. HypokalemiaSerum potassium levels <3.5 mEq/LCauses : DiarrhoeaVillous tumor of rectumAfter trauma or surgeryGastric outlet obstructionDuodenal fistula10/5/200948

50. Clinical features Slurred speechMuscular hypotoniaDepressed reflexesParalytic ileusWeakness of respiratory musclesCardiac arrhythmiasECG shows prolonged QT interval , depessed ST segment and inversion of T waves10/5/200949

51. TreatmentOral potassium 2g 6th hourlyIntravenous KCl 40 mmol/litre given in 5% dextrose of normal saline, under ECG monitoringMax dose per hour = 20 mmol10/5/200950

52. HyperkalemiaNormal range of K = 3.5-5 mEq/LHyperkalemia >6 mEq/LCausesRenal failureRapid infusion of potassiumMassive blood transfusionDiabetic ketoacidosisPotassium sparing diuretics10/5/200951

53. Dangerous condition, can cause sudden cardiac arrest.High serum potassium levelsPeaked ‘T’ waves in ECG10/5/200952

54. Treatment IV admin. Of 50 ml of 50% glucose with 10 units of soluble insulin, slowly.Hemodialysis if life threatening.Correction of acidosis.10/5/200953

55. HypermagnesimiaIt is rareOccurs because of renal failure or during treatment of pre eclampsia for which magnesium sulfate is given.10/5/200954

56. HypomagnesimiaCauses : Malnutrition Large GI fluid lossPatients on Total Parenteral Nutrition 10/5/200955

57. Clinical featuresHyperreflexiaMuscle spasmParaesthesiaTetanyIt mimics hypocalcemiaOften associated with hypokalemia and hypocalcemiaIV/Oral magnesium is needed.10/5/200956

58. HypocalcemiaCauses HypoparathyroidismSevere pancreatitisSevere traumaCrush injuries10/5/200957

59. Clinical featuresCircumoralparasthesiaHyperactive DTRsCarpopedal spasm Adbdominal crampsRarely, convulsionsECG shows prolonged Q-T interval10/5/200958

60. Treatment Treatment of alkalosis, if presentIntravenous calcium gluconateVitamin DOral calcium suplements10/5/200959

61. HypercalcemiaCauses :HyperparathyroidismCancer with bony metastasisSarcoidosisProlonged immobilization 10/5/200960

62. Clinical featuresFatigueMuscle weaknessDepressionAnorexiaConstipation 10/5/200961

63. Treatment Expand ECF by IV normal salineAlso increases urinary output and thus increasing calcium excretion.Hemodialysis in case of renal failure.10/5/200962

64. THANK YOU10/5/200963