fluid, electrolyte, and acid-base balance chapter 26
TRANSCRIPT
Fluid, Electrolyte, and Fluid, Electrolyte, and Acid-Base BalanceAcid-Base Balance
Chapter 26Chapter 26
Body Water ContentBody Water Content
Varies with weight, age, and sex:Varies with weight, age, and sex: Early embryo (97%)Early embryo (97%) Newborn (77%)Newborn (77%) Adult male (60%)Adult male (60%) Adult female (54%)Adult female (54%) Elderly (45%)Elderly (45%)
Adipose tissue versus skeletal Adipose tissue versus skeletal muscle largely determines adult muscle largely determines adult differences.differences.
Body Fluids and CompartmentsBody Fluids and Compartments
Composition of Body FluidsComposition of Body Fluids
ElectrolytesElectrolytes CationsCations: sodium, potassium, hydrogen, : sodium, potassium, hydrogen,
magnesium, and calciummagnesium, and calcium AnionsAnions: chloride, bicarbonate, phosphate, and : chloride, bicarbonate, phosphate, and
sulfatesulfate
Non-electrolytesNon-electrolytes GlucoseGlucose UreaUrea ProteinProtein LipidsLipids CreatinineCreatinine
Comparison of CompartmentsComparison of Compartments
Fluid Movement Between Fluid Movement Between CompartmentsCompartments
Fluid MovementsFluid Movements
Exchange between blood and interstitial spacesExchange between blood and interstitial spaces
Fluid MovementsFluid Movements
Exchange between extracellular fluids and cellsExchange between extracellular fluids and cells
WaterWater BalanceBalance
Regulation of Water IntakeRegulation of Water Intake
Regulation of Water OutputRegulation of Water Output
Regulation of Water OutputRegulation of Water Output
Obligatory Water LossesObligatory Water Losses Skin and lungsSkin and lungs Urine and fecesUrine and feces
Fluid intakeFluid intake
DietDiet
Levels of Anti-diuretic hormone (ADH)Levels of Anti-diuretic hormone (ADH)
Disturbances in Water BalanceDisturbances in Water Balance
DehydrationDehydration
Hypotonic Hypotonic hydrationhydration
EdemaEdema
Electrolyte BalanceElectrolyte Balance
Regulation of Sodium BalanceRegulation of Sodium Balance
Regulation of Potassium BalanceRegulation of Potassium Balance
Regulation of Calcium and Phosphate Regulation of Calcium and Phosphate BalanceBalance
Regulation of Magnesium BalanceRegulation of Magnesium Balance
Regulation of AnionsRegulation of Anions
Regulation of SodiumRegulation of SodiumBy AldosteroneBy Aldosterone
Regulation of Sodium By ANPRegulation of Sodium By ANP
Regulation of SodiumRegulation of SodiumBy BaroreceptorsBy Baroreceptors
Regulation of SodiumRegulation of Sodium
AldosteroneAldosterone ANPANP BaroreceptorsBaroreceptors Other hormones: Other hormones:
Estrogen=enhances Na+ reabsorptionEstrogen=enhances Na+ reabsorption Progesterone=decreases Na+ reabsorptionProgesterone=decreases Na+ reabsorption Glucocorticoids=enhances Na+ Glucocorticoids=enhances Na+
reabsorptionreabsorption
Regulation of PotassiumRegulation of Potassium
The regulatory site of potassium is in The regulatory site of potassium is in the renal tubulesthe renal tubules
Influence of aldosteroneInfluence of aldosterone
Influence of plasma potassium Influence of plasma potassium concentrationsconcentrations
Regulation of CalciumRegulation of Calcium
Influence of Influence of Parathyroid Parathyroid HormoneHormone
Influence of Influence of CalcitoninCalcitonin
Regulation of PhosphateRegulation of Phosphate
Influence of Parathyroid HormoneInfluence of Parathyroid Hormone Decreases plasma phosphate concentrations Decreases plasma phosphate concentrations
while increasing calcium concentrationswhile increasing calcium concentrations
Influence of CalcitoninInfluence of Calcitonin Increases plasma phosphate concentration Increases plasma phosphate concentration
while decreasing calcium concentrationswhile decreasing calcium concentrations
Regulation of Magnesium Balance Regulation of Magnesium Balance and Anionsand Anions
MagnesiumMagnesium PTH increases plasma magnesium PTH increases plasma magnesium
concentrations by causing a decrease in concentrations by causing a decrease in the amount of magnesium excreted by the the amount of magnesium excreted by the kidneyskidneys
AnionsAnions Chloride is Chloride is indirectlyindirectly increased by increased by
Aldosterone because it passively follows Aldosterone because it passively follows sodiumsodium
Acid-Base BalancesAcid-Base Balances
Strong Acids versus Weak AcidsStrong Acids versus Weak Acids
Chemical BuffersChemical BuffersThree Types:Three Types:
Bicarbonate BuffersBicarbonate Buffers
Phosphate BuffersPhosphate Buffers
Protein BuffersProtein Buffers
Bicarbonate BuffersBicarbonate Buffers
Major extracellular buffering systemMajor extracellular buffering system
HCOHCO33-- functions as a weak base while functions as a weak base while
HH22COCO33 functions as a weak acid. functions as a weak acid.
Example:Example:HCl + NaHCOHCl + NaHCO33- - HH22COCO33 + NaCl + NaCl
Phosphate BuffersPhosphate Buffers
Important in urine and intracellular Important in urine and intracellular buffering systemsbuffering systems
However NaHHowever NaH22POPO44 acts as the weak acid acts as the weak acid and Naand Na22HPOHPO44 serves as the weak base. serves as the weak base.
Example:Example:HCl + NaHCl + Na22HPOHPO44 NaHNaH22POPO44 + NaCl + NaCl
Protein BuffersProtein Buffers
Most abundant buffering system in Most abundant buffering system in the body including intracellular and the body including intracellular and extracellular compartments.extracellular compartments.
Carboxyl groups (COOH) and amine Carboxyl groups (COOH) and amine groups (NHgroups (NH33) act as either an acid or ) act as either an acid or a base respectively.a base respectively.
Physiological BuffersPhysiological Buffers
Two Types:Two Types:
Respiratory Buffering SystemRespiratory Buffering System
Renal Buffering SystemRenal Buffering System
Respiratory Regulation of HRespiratory Regulation of H++
Rising plasma HRising plasma H++ causes deeper, rapid breathing which causes deeper, rapid breathing which decreases COdecreases CO2 2 blood thereby decreasing Hblood thereby decreasing H++ ions. ions.
Renal Buffering SystemRenal Buffering System
Reabsorption of HCO3- is coupled to H+
secretion
Abnormalities in Abnormalities in Acid-Base BalanceAcid-Base Balance
Respiratory acidosisRespiratory acidosis Increased COIncreased CO22=increased H=increased H++=decreased pH=decreased pH Cause: HypoventilationCause: Hypoventilation To compensate: Kidney function=increase To compensate: Kidney function=increase
excretion of H+ or by increased reabsorption of excretion of H+ or by increased reabsorption of HCOHCO33--
Respiratory alkalosisRespiratory alkalosis Decreased CODecreased CO22=decreased H=decreased H++=increased pH=increased pH Cause: HyperventilationCause: Hyperventilation To compensate: Kidney function=decreased H+ To compensate: Kidney function=decreased H+
excretion or by decreased reabsorption of HCOexcretion or by decreased reabsorption of HCO33--
Abnormalities in Abnormalities in Acid-Base BalanceAcid-Base Balance
Metabolic acidosisMetabolic acidosis Decreased HCODecreased HCO33
--=increased H=increased H++=decreased pH=decreased pH Cause: Diarrhea, ketosis, renal dysfunctionCause: Diarrhea, ketosis, renal dysfunction To compensate: Hyperventilation and kidney functionTo compensate: Hyperventilation and kidney function
Metabolic alkalosisMetabolic alkalosis Increased HCOIncreased HCO33
--=decreased H=decreased H++=increased pH=increased pH Cause: Vomiting, diuretics, alkaline drug useCause: Vomiting, diuretics, alkaline drug use To compensate: Hypoventilation and kidney functionTo compensate: Hypoventilation and kidney function
Causes and Consequences of Causes and Consequences of Acid-Base ImbalancesAcid-Base Imbalances
Causes and Consequences of Causes and Consequences of Acid-Base ImbalancesAcid-Base Imbalances
Homeostatic ImbalancesHomeostatic Imbalances
HypernatremiaHypernatremia HyponatremiaHyponatremia HyperkalemiaHyperkalemia HypokalemiaHypokalemia HyperphosphatemiHyperphosphatemi
aa HypophosphatemiaHypophosphatemia HyperchloremiaHyperchloremia
HypochloremiaHypochloremia HypercalcemiaHypercalcemia HypocalcemiaHypocalcemia HypermagnesemiaHypermagnesemia HypomagnesemiaHypomagnesemia HyperproteinemiaHyperproteinemia HypoproteinemiaHypoproteinemia
Homeostatic ImbalancesHomeostatic Imbalances
Homeostatic ImbalancesHomeostatic Imbalances
END TEST IV END TEST IV MATERIALMATERIAL