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Acid base homeostasis
- 1. ACID BASEACID BASE BALANCEBALANCE Lifeis a struggle, not against sin, not against Money Power . . but against hydrogen ions.
- 2. 2 ACID BASE HOMEOSTASISACIDBASE HOMEOSTASIS ♥Acid-Base homeostasis involves chemicalchemical and physiologicphysiologic processes responsible for the maintenance of the acidity of body fluids at levels that allow optimal function of the whole individual
- 3. 3 ACID BASE HOMEOSTASISACIDBASE HOMEOSTASIS ♥The chemical processeschemical processes represent the first line of defense to an acid or base load and include the extracellular and intracellularintracellular buffersbuffers ♥The physiologic processesphysiologic processes modulate acid-base composition by changes in cellular metabolism and by adaptive responses in the excretionexcretion of volatile acids by the lungslungs and fixed acids by the kidneyskidneys
- 4. 4 ACID BASE HOMEOSTASISACIDBASE HOMEOSTASIS ♥The need for the existence of multiple mechanisms involved in Acid-BaseAcid-Base regulation stems from the critical importance of the hydrogen ion (H+ ) concentration on the operation of many cellular enzymes and function of vital organs, most prominently the brain and the heart
- 5. 5 ACID BASE HOMEOSTASISACIDBASE HOMEOSTASIS ♥The task imposed on the mechanisms that maintain Acid-BaseAcid-Base homeostasis is large ♠Metabolic pathways are continuously consuming or producing HH++ ♠The daily load of waste products for excretion in the form of volatile and fixed acids is substantial
- 6. 6 EFFECTS OF pHEFFECTSOF pH ♥The most general effect of pH changes are on enzyme function ♠Also affect excitability of nerve and muscle cells p H p Excitabilit y Excitabili
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- 8. 8 ACID-BASE BALANCEACID-BASE BALANCE ♥Acid- BaseAcid - Base balance is primarily concerned with two ions: ♠HydrogenHydrogen (H+ ) ♠BicarbonateBicarbonate (HCO3 - ) H+ HCO3 -
- 9. 9 ACID-BASE BALANCEACID-BASE BALANCE ♥Derangementsof hydrogen and bicarbonate concentrations in body fluids are common in disease processes
- 10. 10 ACID-BASEACID-BASE BALANCEBALANCE ♥HH++ ion has special significance because ofthe narrow ranges that it must be maintained in order to be compatible with living systems
- 11. 11 ACID-BASE BALANCEACID-BASE BALANCE Norm al ♥Primarily controlledby regulation of HH++ ions in the body fluids ♠Especially extracellular fluids
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- 13. 13 ACID-BASE REGULATIONACID-BASE REGULATION ♥Maintenanceof an acceptable pH range in the extracellular fluids is accomplished by threethree mechanisms: ♠1)1) Chemical BuffersChemical Buffers ♦React very rapidly (less than a second) ♠2)2) Respiratory RegulationRespiratory Regulation ♦Reacts rapidly (seconds to minutes) ♠3)3) Renal RegulationRenal Regulation ♦Reacts slowly (minutes to hours)
- 14. 14 ACID-BASE REGULATIONACID-BASE REGULATION ♥ChemicalBuffersChemical Buffers ♠The body uses pH buffers in the blood to guard against sudden changes in acidity ♠A pH buffer works chemically to minimize changes in the pH of a solution Buffe
- 15. 15 ACID-BASE REGULATIONACID-BASE REGULATION ♥RespiratoryRegulationRespiratory Regulation ♠Carbon dioxide is an important by-product of metabolism and is constantly produced by cells ♠The blood carries carbon dioxide to the lungs where it is exhaled CO 2 CO 2 CO 2 CO 2 CO 2CO 2 Cell Metabolis m
- 16. 16 ACID-BASE REGULATIONACID-BASE REGULATION ♥RespiratoryRegulationRespiratory Regulation ♠When breathing is increased, the blood carbon dioxide level decreases and the blood becomes more BaseBase ♠When breathing is decreased, the blood carbon dioxide level increases and the blood becomes more AcidicAcidic ♠By adjusting the speed and depth of breathing, the respiratory control centers and lungs are able to regulate the blood pH minute by minute
- 17. 17 ACID-BASE REGULATIONACID-BASE REGULATION ♥KidneyRegulationKidney Regulation ♠Excess acid is excreted by the kidneys, largely in the form of ammonia ♠The kidneys have some ability to alter the amount of acid or base that is excreted, but this generally takes several days
- 18. 18 ACID-BASE REGULATIONACID-BASE REGULATION ♥Enzymes,hormones and ion distribution are all affected by Hydrogen ion concentrations
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- 20. 20 ACIDSACIDS ♥Acids can bedefined as a proton (HH++ ) donor ♥Hydrogen containing substances which dissociate in solution to release HH++ Click Here
- 21. 21 ACIDSACIDS ♥Acids can bedefined as a proton (HH++ ) donor ♥Hydrogen containing substances which dissociate in solution to release HH++ H+ OH- H+ OH- H+ O H- H+ OH-
- 22. 22 ACIDSACIDS ♥Many other substance(carbohydrates) also contain hydrogen but they are not classified as acids because the hydrogen is tightly bound within their molecular structure and it is never liberated as free HH++ H+ OH- H+ OH- H+ O H- H+ OH-
- 23. 23 ACIDSACIDS ♥Physiologically important acidsinclude: ♠Carbonic acid (HCarbonic acid (H22 COCO33 )) ♠Phosphoric acid (HPhosphoric acid (H33 POPO44 )) ♠Pyruvic acid (CPyruvic acid (C33 HH44 OO33 )) ♠Lactic acid (CLactic acid (C33 HH66 OO33 )) ♥These acids are dissolved in body fluids Lactic acid Pyruvic acid Phosphoric acid
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- 25. 25 BASESBASES ♥Bases can bedefined as: ♠A proton (HH++ ) acceptor ♠Molecules capable of accepting a hydrogen ion (OHOH-- ) Click Here
- 26. 26 BASESBASES ♥Physiologically important basesinclude: ♠Bicarbonate (HCOBicarbonate (HCO33 -- )) ♠Biphosphate (HPOBiphosphate (HPO44 -2-2 )) Biphosphat e
- 27. 27 ♥pH refers toPPotential HHydrogen ♥Expresses hydrogen ion concentration in water solutions ♥Water ionizes to a limited extent to form equal amounts of HH++ ions and OHOH-- ions ♠HH22 OO HH++ + OH+ OH-- ♦HH++ ion is an acid ♦OHOH-- ion is a base pH SCALEpH SCALE
- 28. 28 ♥H+ ion is anacid pH SCALEpH SCALE
- 29. 29 ♥OH- ion is abase pH SCALEpH SCALE
- 30. 30 ♥Pure water isNeutralNeutral ♠ ( H+ = OH- ) ♦ pH = 7 ♥AcidAcid ♠( H+ > OH- ) ♦pH < 7 ♥BaseBase ♠( H+ < OH- ) ♦ pH > 7 ♥Normal blood pH is 7.35 - 7.457.35 - 7.45 ♥pH range compatible with life is 6.8 - 8.06.8 - 8.0 pH SCALEpH SCALE OH- OH- OH- OH- OH- OH- H+ H+ H+ H+ OH- OH- OH- OH-OH- H+ H+ H+ H+ OH- OH- OH- H+ H+ H+ H+ H+ H+ H+ ACIDS, BASES OR NEUTRAL???ACIDS, BASES OR NEUTRAL??? 1 2 3
- 31. 31 pH SCALEpH SCALE ♥pHequals the logarithm (log) to the base 10 of the reciprocal of the hydrogen ion (HH++ ) concentration ♥HH++ concentration in extracellular fluid (ECF) pH = log 1 / HH++ concentration 4 X 10 -8 (0.00000004)
- 32. 32 pH SCALEpH SCALE ♥LowpH values = high HH++ concentrations ♠HH++ concentration in denominator of formula ♥Unit changes in pH represent a tenfold change in HH++ concentrations ♠Nature of logarithms pH = log 1 / HH++ concentration 4 X 10 -8 (0.00000004)
- 33. 33 pH SCALEpH SCALE ♥pH= 4 is more acidic than pH = 6 ♥pH = 4 has 10 times more free HH++ concentration than pH = 5 and 100 times more free HH++ concentration than pH = 6 ACIDOSIS ALKALOSISNORMAL DEATH DEATH Venou s Blood Arteria l Blood 7.3 7.57.46.8 8.0
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- 37. 37 ACIDOSIS / ALKALOSISACIDOSIS/ ALKALOSIS ♥An abnormality in one or more of the pH control mechanisms can cause one of two major disturbances in Acid-BaseAcid-Base balance ♠AcidosisAcidosis ♠AlkalosisAlkalosis
- 38. 38 ACIDOSIS / ALKALOSISACIDOSIS/ ALKALOSIS ♥AcidosisAcidosis ♠A condition in which the blood has too much acid (or too little base), frequently resulting in a decrease in blood pH ♥AlkalosisAlkalosis ♠A condition in which the blood has too much base (or too little acid), occasionally resulting in an increase in blood pH
- 39. 39 ACIDOSIS / ALKALOSISACIDOSIS/ ALKALOSIS ♥Acidosis and alkalosis are not diseases but rather are the results of a wide variety of disorders ♥The presence of acidosis or alkalosis provides an important clue to physicians that a serious metabolic problem exists
- 40. 40 ACIDOSIS / ALKALOSISACIDOSIS/ ALKALOSIS ♥pH changes have dramatic effects on normal cell function ♠1)1) Changes in excitability of nerve and muscle cells ♠2)2) Influences enzyme activity ♠3)3) Influences KK++ levels
- 41. 41 CHANGES IN CELLCHANGESIN CELL EXCITABILITYEXCITABILITY ♥pH decrease (more acidic) depresses the central nervous system ♠Can lead to loss of consciousness ♥pH increase (more basic) can cause over-excitability ♠Tingling sensations, nervousness, muscle twitches
- 42. 42 INFLUENCES ON ENZYMEINFLUENCESON ENZYME ACTIVITYACTIVITY ♥pH increases or decreases can alter the shape of the enzyme rendering it non- functional ♥Changes in enzyme structure can result in accelerated or depressed metabolic actions within the cell
- 43. 43 INFLUENCES ON KINFLUENCESON K++ LEVELSLEVELS ♥When reabsorbing NaNa++ from the filtrate of the renal tubules KK++ or HH++ is secreted (exchanged) ♥Normally KK++ is secreted in much greater amounts than HH++ K+ K+ K+ K+ K+ K+ K+ Na+ Na+ Na+ Na+ Na+ Na+ H+
- 44. 44 INFLUENCES ON KINFLUENCESON K++ LEVELSLEVELS ♥If HH++ concentrations are high (acidosis) than HH++ is secreted in greater amounts ♥This leaves less KK++ than usual excreted ♥The resultant KK++ retention can affect cardiac function and other systems K+ K+ K+ Na+ Na+ Na+ Na+ Na+ Na+ H+ H+ H+ H+ H+ H+ H+ K+ K+ K+ K+ K+
- 45. 45 ♥A relative increasein hydrogen ions results in acidosisacidosis ACIDOSISACIDOSIS H+ OH-
- 46. 46 ♥A relative increasein bicarbonate results in alkalosisalkalosis ALKALOSISALKALOSIS H+ OH-
- 47. 47 ♥AlkalosisAlkalosis ACIDOSIS / ALKALOSISACIDOSIS/ ALKALOSIS H+ OH- ♥AcidosisAcidosis H+ OH-
- 48. 48 ♥Normal ratio ofHCOHCO33 -- to HH22 COCO33 is 20:1 ♠HH22 COCO33 is source of HH++ ions in the body ♥Deviations from this ratio are used to identify Acid-BaseAcid-Base imbalances ACIDOSIS / ALKALOSISACIDOSIS / ALKALOSIS BASE ACID H2CO H+ HCO3
- 49. 49 ACIDOSIS / ALKALOSISACIDOSIS/ ALKALOSIS ♥AcidosisAcidosis and AlkalosisAlkalosis can arise in two fundamentally different ways: ♠1) Excess or deficit of CO1) Excess or deficit of CO22 ((Volatile AcidVolatile Acid)) ♦Volatile AcidVolatile Acid can be eliminated by the respiratory system ♠2) Excess or deficit of2) Excess or deficit of Fixed AcidFixed Acid ♦Fixed AcidsFixed Acids cannot be eliminated by the respiratory system
- 50. 50 ACIDOSIS / ALKALOSISACIDOSIS/ ALKALOSIS ♥Normal values of bicarbonate (arterial) ♠pHpH = 7.4 ♠PCOPCO22 = 40 mm Hg ♠HCOHCO33 -- = 24 meq/L
- 51. 51 ACIDOSISACIDOSIS ♥A decrease ina normal 20:1 base to acid ratio ♠An increase in the number of hydrogen ions (ex: ratio of 20:2 translated to 10:1) ♠A decrease in the number of bicarbonate ions (ex: ratio of 10:1) ♥Caused by too much acid or too little base ACI BAS
- 52. 52 ALKALOSISALKALOSIS ♥An increase inthe normal 20:1 base to acid ratio ♠A decrease in the number of hydrogen ions (ex: ratio of 20:0.5 translated to 40:1) ♠An increase in the number of bicarbonate ions (ex: ratio of 40:1) ♥Caused by base excess or acid deficit ACI BAS
- 53. 53 SOURCES OFSOURCES OF HYDROGENIONSHYDROGEN IONS C C C C C C H H H H H H HHHHHH
- 54. 54 SOURCES OF HYDROGENSOURCESOF HYDROGEN IONSIONS ♥1) Cell Metabolism (CO1) Cell Metabolism (CO22 )) ♥2) Food Products2) Food Products ♥3) Medications3) Medications ♥4) Metabolic Intermediate by-4) Metabolic Intermediate by- productsproducts ♥5) Some Disease processes5) Some Disease processes
- 55. 55 SOURCES OF HYDROGENSOURCESOF HYDROGEN IONSIONS ♥1) Cellular Metabolism1) Cellular Metabolism of carbohydrates release COCO22 as a waste product ♠Aerobic respiration CC66 HH1212 OO66 COCO22 + H+ H22 O + EnergyO + Energy
- 56. 56 SOURCES OF HYDROGENSOURCESOF HYDROGEN IONSIONS ♥COCO22 diffuses into the bloodstream where the reaction: COCO22 + H+ H22 O HO H22 COCO33 HH++ + HCO+ HCO33 -- ♥This process occurs in red blood cells ♠HH22 COCO33 (carbonic acid) ♠Acids produced as a result of the presence of COCO22 is referred to as a Volatile acidVolatile acid
- 57. 57 SOURCES OF HYDROGENSOURCESOF HYDROGEN IONSIONS ♥Dissociation of HH22 COCO33 results in the production of free HH++ and HCOHCO33 -- ♥The respiratory system removes COCO22 thus freeing HCOHCO33 -- to recombine with HH++ ♥Accumulation or deficit of COCO22 in blood leads to respective HH++ accumulations or deficits CO2 H+ CO2 H+ p H p H
- 58. 58 CARBON DIOXIDE DIFFUSIONCARBONDIOXIDE DIFFUSION COCO22 COCO22 Red Blood CellRed Blood Cell SystemicSystemic CirculationCirculation COCO22 HH22 OO HH++ HCOHCO33 -- ++ ++ HCOHCO33 -- ClCl-- (Chloride(Chloride Shift)Shift) COCO22 diffuses into plasma and into RBCdiffuses into plasma and into RBC Within RBC, the hydration of COWithin RBC, the hydration of CO22 isis catalyzed by carbonic anhydrasecatalyzed by carbonic anhydrase Bicarbonate thus formed diffuses intoBicarbonate thus formed diffuses into plasmaplasma carboniccarbonic anhydraseanhydrase TissuesTissues PlasmaPlasma
- 59. 59 CARBON DIOXIDE DIFFUSIONCARBONDIOXIDE DIFFUSION COCO22 Red Blood CellRed Blood Cell Systemic CirculationSystemic Circulation HH22 OO HH++ HCOHCO33 -- carboniccarbonic anhydraseanhydrase PlasmaPlasma COCO22 COCO22 COCO22 COCO22 COCO22 COCO22 COCO22 Click for Carbon Dioxide diffusion ++ ++ TissuesTissues HH++ ClCl-- HbHb HH++ is buffered byis buffered by HemoglobinHemoglobin
- 60. 60 SOURCES OF HYDROGENSOURCESOF HYDROGEN IONSIONS ♥2) Food products2) Food products ♠Sauerkraut ♠Yogurt ♠Citric acid in fruits
- 61. 61 SOURCES OF HYDROGENSOURCESOF HYDROGEN IONSIONS ♥3) Medications3) Medications ♠May stimulate HClHCl production by parietal cells of the stomach
- 62. 62 SOURCES OF HYDROGENSOURCESOF HYDROGEN IONSIONS ♥4) Metabolic4) Metabolic IntermediateIntermediate by-productsby-products ♠Lactic acid ♠Pyruvic acid ♠Acetoacetic acid ♠Fatty acids CC66 HH1212 OO66 22
- 63. 63 SOURCES OF HYDROGENSOURCESOF HYDROGEN IONSIONS ♥Inorganic acids can also be produced during breakdown of nutrients ♠ProteinsProteins (meat products) ♦Breakdown leads to productions of sulfuric acid and phosphoric acid ♠FruitsFruits and VegetablesVegetables ♦Breakdown produces bases which can help to equalize acid production
- 64. 64 SOURCES OF HYDROGENSOURCESOF HYDROGEN IONSIONS ♥5) Some disease processes5) Some disease processes ♠Ex: diabetes causes improper metabolism of fats which results in the generation of a waste product called a Keto AcidKeto Acid
- 65. 65 SOURCES OFSOURCES OF BICARBONATEIONSBICARBONATE IONS
- 66. 66 SOURCES OF BICARBONATESOURCESOF BICARBONATE IONSIONS ♥1) CO1) CO22 diffusion into red blooddiffusion into red blood cellscells ♥2) Parietal cell2) Parietal cell secretion of thesecretion of the gastric mucosagastric mucosa
- 67. 67 1) CO1) CO22DIFFUSIONDIFFUSION ♥Hemoglobin buffers H+ ♥Chloride shift insures electrical neutrality Hb Cl- H+ H+ H+ H+ H+ H+ H+ H+ Cl- Cl- Cl- Cl- Cl- Cl- Red Blood Cell Cl-
- 68. 68 CARBON DIOXIDE DIFFUSIONCARBONDIOXIDE DIFFUSION COCO22 COCO22 Red Blood CellRed Blood Cell Systemic CirculationSystemic Circulation COCO22 HH22 OO HH++ HCOHCO33 -- ++ ++ HCOHCO33 -- ClCl-- (Chloride(Chloride Shift)Shift) COCO22 diffuses into the plasma and intodiffuses into the plasma and into the RBCthe RBC Within the RBC, the hydration of COWithin the RBC, the hydration of CO22 isis catalyzed by carbonic anhydrasecatalyzed by carbonic anhydrase carboniccarbonic anhydraseanhydrase TissuesTissues PlasmaPlasma
- 69. 69 BICARBONATE DIFFUSIONBICARBONATE DIFFUSION RedBlood CellRed Blood Cell Pulmonary CirculationPulmonary Circulation COCO22 HH22 OO HH++ HCOHCO33 -- ++ ++ HCOHCO33 -- ClCl-- AlveolusAlveolus PlasmaPlasma COCO22 Bicarbonate diffuses back into RBC inBicarbonate diffuses back into RBC in pulmonary capillaries and reacts withpulmonary capillaries and reacts with hydrogen ions to form carbonic acidhydrogen ions to form carbonic acid The acid breaks down to COThe acid breaks down to CO22 and waterand water
- 70. 70 BICARBONATE DIFFUSIONBICARBONATE DIFFUSION RedBlood CellRed Blood Cell Pulmonary CirculationPulmonary Circulation COCO22 HH22 OO HH++ ++ ++ HCOHCO33 -- ClCl-- AlveolusAlveolus PlasmaPlasma COCO22 COCO22 HH22 OO
- 71. 71 2) PARIETAL CELL2)PARIETAL CELL SECRETIONSECRETION ♥Bicarbonate ions diffuse into the bloodstream to maintain electrical neutrality in the parietal cell Bloo d Lumen of Stomac h Parieta l Cells H+ Cl- HCO3 - HCl Click to see ion movement CO2 + H2O ♥Secrete hydrogen ions into the lumen of the stomach
- 72. 72 PANCREATIC CELLPANCREATIC CELL SECRETIONSECRETION Bloo d Pancreati c duct Pancreatic Cells H+ HCO3 - Clickto see ion movement ♥H+ ions are secreted into the blood and bicarbonate ions diffuse into pancreatic juice ♥In pancreatic cells the direction of ion movement is reversed HCO3 -
- 73. 73 PARIETAL CELL SECRETIONPARIETALCELL SECRETION ♥If the two processes are balanced, there is no net change in the amount of bicarbonate in blood ♠Loss of gastric or pancreatic juice can change that balance HCO3 - HCO3HCO3 HCO3 - HCO3 - HCO3 -
- 74. 74 ♥Cells of thegastric mucosa secrete H+ ions into the lumen of the stomach in exchange for the diffusion of bicarbonate ions into blood ♥The direction of the diffusion of these ions is reversed in pancreatic epithelial cells BICARBONATE SECRETIONBICARBONATE SECRETION Parietal cells of gastric mucosa Pancreatic epithelial cells HCO3 - H+ HCO3 - H+ lumen of stomach pancreatic juice blood blood
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- 76. 76 ACIDOSIS / ALKALOSISACIDOSIS/ ALKALOSIS ♥Deviations from normal Acid-Base status are divided into fourfour general categories, depending on the source and direction of the abnormal change in HH++ concentrations ♠Respiratory AcidosisRespiratory Acidosis ♠Respiratory AlkalosisRespiratory Alkalosis ♠Metabolic AcidosisMetabolic Acidosis ♠Metabolic AlkalosisMetabolic Alkalosis
- 77. 77 ACIDOSIS / ALKALOSISACIDOSIS/ ALKALOSIS ♥Acidosis and Alkalosis are categorized as MetabolicMetabolic or RespiratoryRespiratory depending on their primary cause ♠Metabolic AcidosisMetabolic Acidosis andand MetabolicMetabolic AlkalosisAlkalosis ♦caused by an imbalance in the production and excretion of acids or bases by the kidneys ♠Respiratory Acidosis and Respiratory Alkalosis ♦caused primarily by lung or breathing disorders
- 78. 78 ACIDOSISACIDOSIS ♥A pH of7.4 corresponds to a 20:1 ratio of HCO3 - and H2CO3 ♠Concentration of HCO3 - is 24 meq/liter and H2CO3 is 1.2 meq/liter Bicarbonat e Carbonic Acid Bicarbonat eBicarbonat eBicarbonat eBicarbonat eBicarbonat eBicarbonat eBicarbonat Bicarbonat eBicarbonat eBicarbonat eBicarbonat e Bicarbonat eBicarbonat eBicarbonat e Bicarbonat eBicarbonat e Bicarbonat eBicarbonat e Bicarbonat 7.
- 79. 79 ACIDOSISACIDOSIS ♥Acidosis is adecreasedecrease in pH below 7.35 ♠Which means a relative increase of HH++ ions ♠pH may fall as low as 7.0 without irreversible damage but any fall less than 7.0 is usually fatal H+ p=
- 80. 80 ACIDOSISACIDOSIS ♥May be causedby: ♠An increase in H2CO3 ♠A decrease in HCO3 - ♥Both lead to a decrease in the ratio of 20:1 H2CO HCO3 -
- 81. 81 ACIDOSISACIDOSIS ♥1) Respiratory Acidosis1)Respiratory Acidosis ♥2) Metabolic Acidosis2) Metabolic Acidosis H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+
- 82. 82 H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ ♥1) Respiratory alkalosis1)Respiratory alkalosis ♥2) Metabolic alkalosis2) Metabolic alkalosis ALKALOSISALKALOSIS
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- 84. 84 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥Causedby hypercapnia due to hypoventilation ♠Characterized by a pH decrease and an increase in COCO22 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 p H p H
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- 86. 86 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥HypercapniaHypercapniais defined as an accumulation of carbon dioxide in extracellular fluids CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 p H p H
- 87. 87 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥Hypercapniais the underlying cause of Respiratory AcidosisRespiratory Acidosis ♠Usually the result of decreased COCO22 removal from the lungs CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 p H p H
- 88. 88 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥Thespeed and depth of breathing control the amount of COCO22 in the blood ♥Normally when COCO22 builds up, the pHpH of the blood falls and the blood becomes acidic ♥High levels of COCO22 in the blood stimulate the parts of the brain that regulate breathing, which in turn stimulate faster and deeper breathing
- 89. 89 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥Respiratoryacidosis develops when the lungs don't expel COCO22 adequately ♥This can happen in diseases that severely affect the lungs, such as emphysema, chronic bronchitis, severe pneumonia, pulmonary edema, and asthma
- 90. 90 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥Respiratoryacidosis can also develop when diseases of the nerves or muscles of the chest impair the mechanics of breathing ♥In addition, a person can develop respiratory acidosis if overly sedated from narcotics and strong sleeping medications that slow respiration
- 91. 91 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥Thetreatment of respiratory acidosis aims to improve the function of the lungs ♥Drugs to improve breathing may help people who have lung diseases such as asthma and emphysema
- 92. 92 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥Decreased COCO22 removal can be the result of: 1)1) Obstruction of airObstruction of air passagespassages 2)2) DecreasedDecreased respirationrespiration (depression of(depression of respiratoryrespiratory centers)centers) 3)3) Decreased gasDecreased gas exchangeexchange betweenbetween pulmonarypulmonary
- 93. 93 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥1)Obstruction of air passages1) Obstruction of air passages ♠Vomit, anaphylaxis, tracheal cancer
- 94. 94 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥2)Decreased Respiration2) Decreased Respiration ♠Shallow, slow breathing ♠Depression of the respiratory centers in the brain which control breathing rates ♦Drug overdose
- 95. 95 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥3)3)DecreasedDecreased gas exchangegas exchange betweenbetween pulmonarypulmonary capillaries andcapillaries and air sacs ofair sacs of lungslungs ♠Emphysema ♠Bronchitis ♠Pulmonary edema
- 96. 96 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS ♥4)4)Collapse of lungCollapse of lung ♠Compression injury, open thoracicCompression injury, open thoracic woundwound Left lung collapsed
- 97. 97 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS -metabolicbalance before onset of acidosis -pH = 7.4 -respiratory acidosis -pH = 7.1 -breathing is suppressed holding CO2 in body -body’s compensation -kidneys conserve HCO3 - ions to restore the normal 40:2 ratio -kidneys eliminate H+ ion in acidic urine - therapy required to restore metabolic balance - lactate solution used in therapy is converted to bicarbonate ions in the liver 40
- 98. 98 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS -metabolic balance before onset of acidosis - pH = 7.4 H2CO 3 HCO3 - 1 20: H2CO3 : Carbonic Acid HCO3 - : Bicarbonate Ion (Na+ ) HCO3 - (K+ ) HCO3 - (Mg++ ) HCO3 - (Ca++ ) HCO3 -
- 99. 99 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS -breathingis suppressed holding CO2 in body -pH = 7.1 H 2 CO 3 HCO3 - 2 20: CO 2 CO 2 CO 2 CO 2
- 100. 100 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS BODY’SCOMPENSATION -kidneys conserve HCO3 - ions to restore the normal 40:2 ratio (20:1) -kidneys eliminate H+ ion in acidic urine H2 CO 3 HCO3 - 2 30: HCO3 - H2CO 3 HCO 3 - H+ + acidic urine
- 101. 101 RESPIRATORY ACIDOSISRESPIRATORY ACIDOSIS -therapy required to restore metabolic balance - lactate solution used in therapy is converted to bicarbonate ions in the liver H2CO 3 HCO3 - 2 40: Lactate Lactat e LIVE R HCO3 -
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- 103. 103 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥Normal20:1 ratio is increased ♠pH of blood is above 7.4 H2CO 3 HCO3 - 1 20: = 7.4 H2 CO 3 HCO3- 0. 5 20: = 7.4
- 104. 104 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥Causeis Hyperventilation ♠Leads to eliminating excessive amounts of COCO22 ♠Increased loss of COCO22 from the lungs at a rate faster than it is produced ♠Decrease in HH++ CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2
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- 106. 106 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥Canbe the result of: ♠1) Anxiety, emotional disturbances ♠2) Respiratory center lesions ♠3) Fever ♠4) Salicylate poisoning (overdose) ♠5) Assisted respiration ♠6) High altitude (low PO2)
- 107. 107 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥Anxietyis an emotional disturbance ♥The most common cause of hyperventilation, and thus respiratory alkalosis, is anxiety
- 108. 108 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥Usuallythe only treatment needed is to slow down the rate of breathing ♥Breathing into a paper bag or holding the breath as long as possible may help raise the blood COCO22 content as the person breathes carbon dioxide back in after breathing it out
- 109. 109 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥RespiratorycenterRespiratory center lesionslesions ♠Damage to brainDamage to brain centers responsiblecenters responsible for monitoringfor monitoring breathing ratesbreathing rates ♦TumorsTumors ♦StrokesStrokes
- 110. 110 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥FFeverever ♠RapidshallowRapid shallow breathing blows offbreathing blows off too muchtoo much COCO22
- 111. 111 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥SalicylatepoisoningSalicylate poisoning (Aspirin overdose)(Aspirin overdose) ♠Ventilation isVentilation is stimulated withoutstimulated without regard to the status ofregard to the status of OO22 ,, COCO22 oror HH++ in thein the body fluidsbody fluids
- 112. 112 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥AssistedRespirationAssisted Respiration ♠Administration ofAdministration of COCO22 in the exhaledin the exhaled air of the care - giverair of the care - giver Your insurance won’t cover a ventilator any longer, so Bob here will be giving you mouth to mouth for the next several days
- 113. 113 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥HighAltitudeHigh Altitude ♠Low concentrations ofLow concentrations of OO22 in the arterialin the arterial blood reflexly stimulates ventilation in anblood reflexly stimulates ventilation in an attempt to obtain moreattempt to obtain more OO22 ♠Too muchToo much COCO22 is “blown off” in theis “blown off” in the processprocess
- 114. 114 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥Kidneyscompensate by: ♠Retaining hydrogen ionsRetaining hydrogen ions ♠Increasing bicarbonateIncreasing bicarbonate excretionexcretion H+ HCO3 - HCO3 - HCO3 - HCO3 - HCO3 - HCO3 - HCO3 - HCO3 - HCO3 - HCO3 - H+ H+ H+ H+ H+ H+ H+ H+ H+ H+
- 115. 115 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS ♥DecreasedCOCO22 in the lungs will eventually slow the rate of breathing ♠Will permit a normal amount of COCO22 to be retained in the lung
- 116. 116 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS -metabolicbalance before onset of alkalosis -pH = 7.4 -respiratory alkalosis -pH = 7.7 - hyperactive breathing “ blows off ” CO2 - body’s compensation - kidneys conserve H+ ions and eliminate HCO3 - in alkaline urine - therapy required to restore metabolic balance - HCO3 - ions replaced by Cl- ions
- 117. 117 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS -metabolicbalance before onset of alkalosis -pH = 7.4 H2CO 3 HCO3 - 1 20: H2CO3 : Carbonic Acid HCO3 - : Bicarbonate Ion (Na+ ) HCO3 - (K+ ) HCO3 - (Mg++ ) HCO3 - (Ca++ ) HCO3 -
- 118. 118 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS -respiratoryalkalosis -pH = 7.7 -hyperactive breathing “ blows off ” CO2 H2 CO 3 HCO3- 0.5 20: CO2 CO2 + H2O
- 119. 119 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS BODY’SCOMPENSATION - kidneys conserve H+ ions and eliminate HCO3 - in alkaline urine H2 CO 3 HCO3 - 0.5 15: HCO3 - Alkaline Urine
- 120. 120 RESPIRATORY ALKALOSISRESPIRATORY ALKALOSIS -therapy required to restore metabolic balance - HCO3 - ions replaced by Cl- ions H2CO 3 HCO3 - 0.5 10: Cl - Chloride containin g solution
- 121. 121 RESPIRATORYRESPIRATORY ACIDOSIS / ALKALOSISACIDOSIS/ ALKALOSIS COCO22 + H+ H22 OO HH22 COCO33 HH++ ++ HCOHCO33 -- Respiratory Acidosis Respiratory Alkalosis
- 122. 122 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Occurswhen there is a decrease in the normal 20:1 ratio ♠Decrease in blood pHpH and bicarbonate level ♥Excessive HH++ or decreased HCOHCO33 -- H2CO 3 HCO3 - 1 20: = 7.4 H 2 CO 3 HCO3 - 1 10: = 7.4
- 123. 123 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Anyacid-base imbalance not attributable to COCO22 is classified as metabolic ♠Metabolic production of AcidsAcids ♠Or loss of BasesBases
- 124. 124 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Ifan increase in acid overwhelms the body's pHpH buffering system, the blood can become acidic ♥As the blood pHpH drops, breathing becomes deeper and faster as the body attempts to rid the blood of excess acid by decreasing the amount of carbon dioxide
- 125. 125 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Eventually,the kidneys also try to compensate by excreting more acid in the urine ♥However, both mechanisms can be overwhelmed if the body continues to produce too much acid, leading to severe acidosis and eventually a coma
- 126. 126 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Metabolicacidosis is always characterized by a reduction in plasma HCOHCO33 -- while COCO22 remains normal HCO3 - CO2 Plasma Levels
- 127. 127 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Acidosisresults from excessive loss of HCOHCO33 -- rich fluids from the body or from an accumulation of acids ♠Accumulation of non-carbonic plasma acids uses HCOHCO33 -- as a buffer for the additional HH++ thus reducing HCOHCO33 -- levels tic d Muscle Cell
- 128. 128 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Thecauses of metabolic acidosis can be grouped into fivefive major categories ♠1)1) Ingesting an acid or a substance that is metabolized to acid ♠2) Abnormal Metabolism2) Abnormal Metabolism ♠3) Kidney Insufficiencies3) Kidney Insufficiencies ♠4) Strenuous Exercise4) Strenuous Exercise ♠5) Severe Diarrhea5) Severe Diarrhea
- 129. 129 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥1)Ingesting An Acid1) Ingesting An Acid ♠Most substances that cause acidosis when ingested are considered poisonous ♠Examples include wood alcohol (methanol) and antifreeze (ethylene glycol) ♠However, even an overdose of aspirin (acetylsalicylic acid) can cause metabolic acidosis
- 130. 130 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥2)Abnormal Metabolism2) Abnormal Metabolism ♠The body can produce excess acid as a result of several diseases ♦One of the most significant is Type I Diabetes Mellitus
- 131. 131 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Unregulated diabetesmellitus causes ketoacidosisketoacidosis ♠Body metabolizes fat rather than glucose ♠Accumulations of metabolic acids (Keto Acids)(Keto Acids) cause an increase in plasma HH++
- 132. 132 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Thisleads to excessive production of ketones:ketones: ♠AcetoneAcetone ♠Acetoacetic acidAcetoacetic acid ♠B-hydroxybutyric acidB-hydroxybutyric acid ♥Contribute excessive numbers of hydrogen ions to body fluids Acetone Acetoacetic acid Hydroxybutyric acid H+ H+ + H+ H+ H+ H+
- 133. 133 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥2)Abnormal Metabolism2) Abnormal Metabolism ♠The body also produces excess acid in the advanced stages of shock, when lactic acid is formed through the metabolism of sugar
- 134. 134 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥3)3)KidneyKidney InsufficienciesInsufficiencies ♠Even the production of normal amounts of acid may lead to acidosis when the kidneys aren't functioning normally
- 135. 135 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥3)Kidney3) Kidney InsufficienciesInsufficiencies ♠Kidneys may be unable to rid the plasma of even the normal amounts of HH++ generated from metabolic acids ♠Kidneys may be also unable to conserve an adequate amount of HCOHCO33 -- to buffer the normal acid load
- 136. 136 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥3)Kidney Insufficiencies3) Kidney Insufficiencies ♠This type of kidney malfunction is called renal tubular acidosisrenal tubular acidosis or uremic acidosisuremic acidosis and may occur in people with kidney failure or with abnormalities that affect the kidneys' ability to excrete acid
- 137. 137 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥4)Strenuous Exercise4) Strenuous Exercise ♠Muscles resort to anaerobic glycolysis during strenuous exercise ♠Anaerobic respiration leads to the production of large amounts of lactic acid C6H12O6 2C3H6O3 + ATP (energy) Enzymes Lactic Acid
- 138. 138 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥5)Severe Diarrhea5) Severe Diarrhea ♠Fluids rich in HCOHCO33 -- are released and reabsorbed during the digestive process ♠During diarrhea this HCOHCO33 -- is lost from the body rather than reabsorbed
- 139. 139 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥5)Severe Diarrhea5) Severe Diarrhea ♠The loss of HCOHCO33 -- without a corresponding loss of H+ lowers the pH ♠Less HCOHCO33 -- is available for buffering HH++ ♠Prolonged deep (from duodenum) vomiting can result in the same situation
- 140. 140 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Treatingthe underlying cause of metabolic acidosis is the usual course of action ♠For example, they may control diabetes with insulin or treat poisoning by removing the toxic substance from the blood ♠Occasionally dialysis is needed to treat severe overdoses and poisonings
- 141. 141 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Metabolicacidosis may also be treated directly ♠If the acidosis is mild, intravenous fluids and treatment for the underlying disorder may be all that's needed
- 142. 142 METABOLIC ACIDOSISMETABOLIC ACIDOSIS ♥Whenacidosis is severe, bicarbonate may be given intravenously ♠Bicarbonate provides only temporary relief and may cause harm
- 143. 143 METABOLIC ACIDOSISMETABOLIC ACIDOSIS -metabolic balance before onset of acidosis - pH 7.4 - metabolic acidosis - pH 7.1 - HCO3 - decreases because of excess presence of ketones, chloride or organic ions - body’s compensation - hyperactive breathing to “ blow off ” CO2 - kidneys conserve HCO3 - and eliminate H+ ions in acidic urine - therapy required to restore metabolic balance - lactate solution used in therapy is converted to bicarbonate ions 0.5 10
- 144. 144 METABOLIC ACIDOSISMETABOLIC ACIDOSIS -metabolicbalance before onset of acidosis -pH 7.4 H2CO3 : Carbonic Acid HCO3 - : Bicarbonate Ion (Na+ ) HCO3 - (K+ ) HCO3 - (Mg++ ) HCO3 - (Ca++ ) HCO3 - H2CO 3 HCO3 - 1 20:
- 145. 145 METABOLIC ACIDOSISMETABOLIC ACIDOSIS -HCO3 - decreasesbecause of excess presence of ketones, chloride or organic ions H 2 CO 3 HCO3 - 1 10: = 7.4
- 146. 146 METABOLIC ACIDOSISMETABOLIC ACIDOSIS BODY’S COMPENSATION-hyperactive breathing to “ blow off ” CO2- kidneys conserve HCO3 - and eliminate H+ ions in acidic urine H2 CO 3 HCO 3 - 0.75 10: CO2 COCO22 ++ HH22 OO HCO3 - + H+ HCOHCO33 -- ++ HH++ Acidic urine
- 147. 147 METABOLIC ACIDOSISMETABOLIC ACIDOSIS -therapy required to restore metabolic balance - lactate solution used in therapy is converted to bicarbonate ions in the H2CO 3 HCO3 - 0.5 10: Lactat e Lactate containin g solution
- 148.
- 149. 149 METABOLIC ALKALOSISMETABOLIC ALKALOSIS ♥Elevationof pHpH due to an increased 20:1 ratio ♠May be caused by: ♦An increase of bicarbonate ♦A decrease in hydrogen ions ♠Imbalance again cannot be due to COCO22 ♠Increase in pHpH which has a non- respiratory origin 7.4
- 150. 150 METABOLIC ALKALOSISMETABOLIC ALKALOSIS ♥Areduction in HH++ in the case of metabolic alkalosis can be caused by a deficiency of non-carbonic acids ♥This is associated with an increase in HCOHCO33 --
- 151. 151 METABOLIC ALKALOSISMETABOLIC ALKALOSIS ♥Treatmentof metabolic alkalosis is most often accomplished by replacing water and electrolytes (sodiumsodium and potassiumpotassium) while treating the underlying cause ♥Occasionally when metabolic alkalosis is very severe, dilute acid in the form of ammonium chloride is given by IV
- 152. 152 METABOLIC ALKALOSISMETABOLIC ALKALOSIS ♥Canbe the result of: ♠1) Ingestion of Alkaline1) Ingestion of Alkaline SubstancesSubstances ♠2) Vomiting ( loss of HCl )2) Vomiting ( loss of HCl )
- 153. 153 METABOLIC ALKALOSISMETABOLIC ALKALOSIS ♥1)Ingestion of Alkaline1) Ingestion of Alkaline SubstancesSubstances ♠Influx of NaHCONaHCO33
- 154. 154 METABOLIC ALKALOSISMETABOLIC ALKALOSIS ♥Bakingsoda (NaHCONaHCO33) often used as a remedy for gastric hyperacidity ♠NaHCONaHCO33 dissociates to NaNa++ and HCOHCO33 --
- 155. 155 METABOLIC ALKALOSISMETABOLIC ALKALOSIS ♥Bicarbonateneutralizes high acidity in stomach (heart burn) ♥The extra bicarbonate is absorbed into the plasma increasing pHpH of plasma as bicarbonate binds with free HH++
- 156. 156 METABOLIC ALKALOSISMETABOLIC ALKALOSIS ♥Commerciallyprepared alkaline products for gastric hyperacidity are not absorbed from the digestive tract and do not alter the pHpH status of the plasma
- 157. 157 METABOLIC ALKALOSISMETABOLIC ALKALOSIS ♥2)Vomiting (abnormal loss of2) Vomiting (abnormal loss of HCl)HCl) ♠Excessive loss of H+
- 158. 158 METABOLIC ALKALOSISMETABOLIC ALKALOSIS ♥Gastricjuices contain large amounts of HClHCl ♥During HClHCl secretion, bicarbonate is added to the plasma K+ H+ Cl- HCO3 - HC l Click to View Animation
- 159. 159 HC l METABOLIC ALKALOSISMETABOLIC ALKALOSIS K+ H+ Cl- HCO3 - Clickto View Animation ♥The bicarbonate is neutralized as HClHCl is reabsorbed by the plasma from the digestive tract H2CO 3
- 160. 160 METABOLIC ALKALOSISMETABOLIC ALKALOSIS HC l K+ HCO3 - Clickto View Animation ♥During vomiting HH++ is lost as HClHCl and the bicarbonate is not neutralized in the plasma ♠Loss of HClHCl increases the plasma bicarbonate and thus results in an increase in pHpH of the blood Bicarbonate notBicarbonate not neutralizedneutralized
- 161. 161 METABOLIC ALKALOSISMETABOLIC ALKALOSIS ♥Reactionof the body to alkalosis is to lower pHpH by: ♠Retain CO2 by decreasing breathing rate ♠Kidneys increase the retention of HH++ CO 2 CO2 H+ H+ H+ H+
- 162. 162 METABOLIC ALKALOSISMETABOLIC ALKALOSIS -metabolic balance before onset of alkalosis - pH = 7.4 - metabolic alkalosis - pH = 7.7 - HCO3 - increases because of loss of chloride ions or excess ingestion of NaHCO3 - body’s compensation - breathing suppressed to hold CO2- kidneys conserve H+ ions and eliminate HCO3 - in alkaline urine - therapy required to restore metabolic balance - HCO3 - ions replaced by Cl- ions1.2 5 25
- 163. 163 METABOLIC ALKALOSISMETABOLIC ALKALOSIS -metabolic balance before onset of alkalosis - pH = 7.4 H2CO3 : Carbonic Acid HCO3 - : Bicarbonate Ion (Na+ ) HCO3 - (K+ ) HCO3 - (Mg++ ) HCO3 - (Ca++ ) HCO3 - H2CO 3 HCO3 - 1 20:
- 164. 164 METABOLIC ALKALOSISMETABOLIC ALKALOSIS -pH = 7.7 - HCO3 - increases because of loss of chloride ions or excess ingestion of HCO3- 1 40: H2 CO 3
- 165. 165 H2CO 3 HCO3 - METABOLIC ALKALOSISMETABOLIC ALKALOSIS BODY’S COMPENSATION-breathing suppressed to hold CO2 - kidneys conserve H+ ions and eliminate HCO3 - in alkaline urine 1.25 30 CO2 + H2O HCO3 - + H+ HCO3 - H+ + Alkaline urine :
- 166. 166 METABOLIC ALKALOSISMETABOLIC ALKALOSIS -Therapy required to restore metabolic balance- HCO3 - ions replaced by Cl- ions H2CO 3 HCO3 - 1.25 25: Cl- Chloride containin g solution
- 167. 167 ACIDOSISACIDOSIS decreased removal of CO2 from lungs failureof kidneys to excrete acids metabolic acid production of keto acids absorption of metabolic acids from GI tract prolonged diarrhea accumulation of CO2 in blood accumulation of acid in blood excessive loss of NaHCO3 from blood metabolic acidosis deep vomiting from GI tract kidney disease (uremia) increase in plasma H+ concentrati on depression of nervous system accumulation of CO2 in blood accumulation of acid in blood excessive loss of NaHCO3 from blood respiratory acidosis
- 168. 168 ALKALOSISALKALOSIS respiratory alkalosis anxiety overdose of certain drugs high altitudes prolonged vomiting ingestionof excessive alkaline drugs excess aldosterone hyperventilati on loss of CO2 and H2CO2 from blood loss of acid accumulation of base metabolic alkalosis decrease in plasma H+ concentrati on overexcitability of nervous system hyperventilati on loss of CO2 and H2CO2 from blood loss of acid accumulation of base
- 169. 169 ACID – BASEDISORDERSACID – BASE DISORDERS Clinical State Acid-Base Disorder Pulmonary Embolus Respiratory Alkalosis Cirrhosis Respiratory Alkalosis Pregnancy Respiratory Alkalosis Diuretic Use Metabolic Alkalosis Vomiting Metabolic Alkalosis Chronic Obstructive Pulmonary Disease Respiratory Acidosis Shock Metabolic Acidosis Severe Diarrhea Metabolic Acidosis Renal Failure Metabolic Acidosis Sepsis (Bloodstream Infection) Respiratory Alkalosis, Metabolic Acidosis
- 170. 170 RESPONSES TO:RESPONSES TO: ACIDOSISAND ALKALOSISACIDOSIS AND ALKALOSIS ♥Mechanisms protect the body against life-threatening changes in hydrogen ion concentration ♠1) Buffering Systems in Body1) Buffering Systems in Body FluidsFluids ♠2) Respiratory Responses2) Respiratory Responses ♠3) Renal Responses3) Renal Responses ♠4) Intracellular Shifts of Ions4) Intracellular Shifts of Ions
- 171. 171 1)1) Buffer SystemsBufferSystems 2) Respiratory Responses2) Respiratory Responses 3) Renal Responses3) Renal Responses 4) Intracellular Shifts of Ions4) Intracellular Shifts of Ions
- 172. 172 BUFFERSBUFFERS ♥Buffering systems providean immediate response to fluctuations in pHpH ♠1) Phosphate1) Phosphate ♠2) Protein2) Protein ♠3) Bicarbonate Buffer System3) Bicarbonate Buffer System
- 173. 173 BUFFERSBUFFERS ♥A buffer isa combination of chemicals in solution that resists any significant change in pHpH ♥Able to bind or release free HH++ ions
- 174. 174 BUFFERSBUFFERS ♥Chemical buffers areable to react immediately (within milliseconds) ♥Chemical buffers are the first line of defense for the body for fluctuations in pHpH
- 175. 175 ♥1) Phosphate buffersystem1) Phosphate buffer system Na2HPO4 + H+ NaH2PO4 + Na+ ♠Most important in the intracellular system PHOSPHATE BUFFERPHOSPHATE BUFFER SYSTEMSYSTEM H+ Na2HPO 4 + NaH2PO 4 Click to animate Na++
- 176. 176 Na2HPO4 + H+ NaH2PO4+ Na+ ♥Alternately switches NaNa++ with HH++ PHOSPHATE BUFFERPHOSPHATE BUFFER SYSTEMSYSTEM H+ Na2HPO 4 + NaH2PO 4 Click to animate Na++ Disodium hydrogen phosphate
- 177. 177 Na2HPO4 + H+ NaH2PO4+ Na+ ♥Phosphates are more abundant within the cell and are rivaled as a buffer in the ICF by even more abundant protein PHOSPHATE BUFFERPHOSPHATE BUFFER SYSTEMSYSTEM Na2HPO 4 Na2HPO 4Na2HPO
- 178. 178 ♥Regulates pHpH withinthe cells and the urine ♠Phosphate concentrations are higher intracellularly and within the kidney tubules ♠Too low of a concentration in extracellular fluid to have much importance as an ECFECF buffer system PHOSPHATE BUFFERPHOSPHATE BUFFER SYSTEMSYSTEM HPO4 - 2
- 179. 179 PROTEIN BUFFER SYSTEMPROTEINBUFFER SYSTEM ♥2) Protein Buffer System2) Protein Buffer System ♠Behaves as a buffer in both plasma and cells ♠Hemoglobin is by far the most important protein buffer
- 180. 180 PROTEIN BUFFER SYSTEMPROTEINBUFFER SYSTEM ♥Most important intracellular buffer (ICFICF) ♥The most plentiful buffer of the body
- 181. 181 PROTEIN BUFFER SYSTEMPROTEINBUFFER SYSTEM ♥Proteins are excellent buffers because they contain both acid and base groups that can give up or take up HH++ ♥Proteins are extremely abundant in the cell ♥The more limited number of proteins in the plasma reinforce the bicarbonate system in the ECFECF
- 182. 182 PROTEIN BUFFER SYSTEMPROTEINBUFFER SYSTEM ♥Hemoglobin buffers HH++ from metabolically produced COCO22 in the plasma only ♥As hemoglobin releases OO22 it gains a great affinity for HH++ HH bb O2 O2 O2 O2
- 183. 183 PROTEIN BUFFER SYSTEMPROTEINBUFFER SYSTEM ♥HH++ generated at the tissue level from the dissociation of HH22 COCO33 produced by the addition of COCO22 ♥Bound HH++ to HbHb (Hemoglobin) does not contribute to the acidity of blood HH bb O2 O2 O2 O2
- 184. 184 PROTEIN BUFFER SYSTEMPROTEINBUFFER SYSTEM ♥As HH++ HbHb picks up OO22 from the lungs the HbHb which has a higher affinity for OO22 releases HH++ and picks up OO22 ♥Liberated HH++ from HH22 OO combines with HCOHCO33 -- HCOHCO33 -- HH22 COCO33 COCO22 (exhaled) HH bb O2 O2 O2 H+
- 185. 185 PROTEIN BUFFER SYSTEMPROTEINBUFFER SYSTEM ♥Venous blood is only slightly more acidic than arterial blood because of the tremendous buffering capacity of HbHb ♥Even in spite of the large volume of HH++ generating COCO22 carried in venous blood
- 186. 186 Pr - added H+ +Pr - PROTEIN BUFFER SYSTEMPROTEIN BUFFER SYSTEM ♥Proteins can act as a buffer for both acids and bases ♥Protein buffer system works instantaneously making it the most powerful in the body ♥75% of the body’s buffer capacity is controlled by protein ♠Bicarbonate and phosphate buffer systems require several hours to be effective
- 187. 187 PROTEIN BUFFER SYSTEMPROTEINBUFFER SYSTEM ♥Proteins are very large, complex molecules in comparison to the size and complexities of acids or bases ♥Proteins are surrounded by a multitude of negative charges on the outside and numerous positive charges in the crevices of the molecule - - - - - - - - - - - - - -------- - --- - - - - - - - - + + ++ + + + + + + + + + ++ + + + + + + + + + +
- 188. 188 PROTEIN BUFFER SYSTEMPROTEINBUFFER SYSTEM ♥H+ ions are attracted to and held from chemical interaction by the negative charges - - - - - - - - - - - - - -------- - --- - - - - - - - - + + ++ + + + + + + + + + ++ + + + + + + + + + + H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+H+ H+ H+ H+ H+ H+
- 189. 189 PROTEIN BUFFER SYSTEMPROTEINBUFFER SYSTEM ♥OH- ions which are the basis of alkalosis are attracted by the positive charges in the crevices of the protein - - - - - - - - - - - - - -------- - --- - - - - - - - - + + ++ + + + + + + + + + ++ + + + + + + + + + + OH- OH- OH- OH- OH- OH- OH- OH- OH- OH- OH- OH-
- 190. 190 PROTEIN BUFFER SYSTEMPROTEINBUFFER SYSTEM - - - - - - - - - - - - - -------- - --- - - - - - - - - + + ++ + + + + + + + + + ++ + + + + + + + + + + OH- OH- OH- OH- OH- OH- OH- OH- OH- OH- OH- OH- H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+ H+H+ H+ H+ H+ H+ H+
- 191. 191 BICARBONATE BUFFERBICARBONATE BUFFER SYSTEMSYSTEM ♥3)Bicarbonate Buffer System3) Bicarbonate Buffer System ♠Predominates in extracellular fluid (ECFECF) HCOHCO33 -- + added H+ added H++ HH22 COCO33 HCOHCO33 -- HH22 COCO33
- 192. 192 BICARBONATE BUFFERBICARBONATE BUFFER SYSTEMSYSTEM ♥Thissystem is most important because the concentration of both components can be regulated: ♠Carbonic acidCarbonic acid by the respiratory system ♠BicarbonateBicarbonate by the renal system
- 193. 193 BICARBONATE BUFFERBICARBONATE BUFFER SYSTEMSYSTEM ♥HH22COCO33 HH++ + HCO+ HCO33 -- ♠Hydrogen ions generated by metabolism or by ingestion react with bicarbonate base to form more carbonic acid HCOHCO33 -- HH22 COCO33
- 194. 194 BICARBONATE BUFFERBICARBONATE BUFFER SYSTEMSYSTEM♥Equilibriumshifts toward the formation of acid ♠Hydrogen ions that are lost (vomiting) causes carbonic acid to dissociate yielding replacement HH++ and bicarbonate HH++ HCOHCO33 -- HH22 COCO33
- 195. 195 Loss of HCl Additionof lactic acid BICARBONATE BUFFERBICARBONATE BUFFER SYSTEMSYSTEM HH++ HCOHCO33 -- HH22 COCO33HH22 OO COCO 22 + ++ Exercis e Vomitin g
- 196. 196 1) Buffer Systems1)Buffer Systems 2) Respiratory2) Respiratory ResponsesResponses 3) Renal Responses3) Renal Responses 4) Intracellular Shifts of Ions4) Intracellular Shifts of Ions
- 197. 197 RESPIRATORY RESPONSERESPIRATORY RESPONSE ♥Neuronsin the medulla oblongata and pons constitute the RespiratoryRespiratory CenterCenter ♥Stimulation and limitation of respiratory rates are controlled by the respiratory center ♥Control is accomplished by responding to CO2 and H+ concentrations in the blood
- 198.
- 199. 199 CHEMOSENSITIVE AREASCHEMOSENSITIVE AREAS ♥Chemosensitiveareas of the respiratory center are able to detect blood concentration levels of CO2 and H+ ♥Increases in CO2 and H+ stimulate the respiratory center ♠The effect is to raise respiration rates ♦But the effect diminishes in 1 - 2 minutes CO2 CO CO2 CO2 CO2 CO2 CO2 CO2Click to increase CO2
- 200. 200 CHEMOSENSITIVE AREASCHEMOSENSITIVE AREAS ♥Theeffect of stimulating the respiratory centers by increased CO2 and H+ is weakened in environmentally increased CO2 levels ♥Symptoms may persist for several days
- 201. 201 CHEMORECEPTORSCHEMORECEPTORS ♥Chemoreceptors are alsopresent in the carotidcarotid and aorticaortic arteries which respond to changes in partial pressures of O2 and CO2 or pH ♥Increased levels of CO2 (low pHpH) or decreased levels of O2 stimulate respiration rates to increase
- 202. 202 CHEMORECEPTORSCHEMORECEPTORS ♥Overall compensatory responseis: ♠HyperventilationHyperventilation in response to increased CO2 or H+ (low pHpH) ♠HypoventilationHypoventilation in response to decreased CO2 or H+ (high pHpH)
- 203. 203 RESPIRATORY CONTROL OFpHRESPIRATORY CONTROL OF pH pH rises toward normal rate and depth of breathing increase CO2 eliminated in lungs H+ stimulates respiratory center in medulla oblongata H2CO3 H+ + HCO3 - H+ acidosis; pH drops CO2 + H2O H2CO3 cell production of CO2 increases
- 204. 204 1)1) Buffer SystemsBufferSystems 2) Respiratory Responses2) Respiratory Responses 3) Renal3) Renal ResponsesResponses 4) Intracellular Shifts of Ions4) Intracellular Shifts of Ions
- 205. 205 RENAL RESPONSERENAL RESPONSE ♥Thekidney compensates for Acid -Acid - BaseBase imbalance within 24 hours and is responsible for long term control ♥The kidney in response: ♠To AcidosisTo Acidosis ♦Retains bicarbonate ions and eliminates hydrogen ions ♠To AlkalosisTo Alkalosis ♦Eliminates bicarbonate ions and retains hydrogen ions
- 206. 206 ACIDIFICATIOACIDIFICATIO N OF URINENOF URINE BY EXCRETIONBY EXCRETION OF AMMONIAOF AMMONIA
- 207. 207 ACIDIFICATION OF URINEBY EXCRETION OFACIDIFICATION OF URINE BY EXCRETION OF AMMONIAAMMONIA Capillar y Distal Tubule Cells Tubular urine to be excreted NH2 H + NH3 NH2 H + NH3 WHAT HAPPENS NEXT?
- 208. 208 Capillar y Distal Tubule Cells Tubular Urine NH3 Na + Cl- + H2CO 3 HCO3 - + NaCl NaHCO3 Click Mouseto Start Animation NaHCO3 NH3Cl- H + NH4Cl Click Mouse to See Animation Again Notice the H+ - Na+ exchange to maintain electrical neutrality ACIDIFICATION OF URINE BY EXCRETION OFACIDIFICATION OF URINE BY EXCRETION OF AMMONIAAMMONIA Dissociation of carbonic acid
- 209. 209 Capillar y Distal Tubule Cells Tubular Urine NH3 Na + Cl- + H2CO 3 HCO3 - + NaCl NaHCO3 Click Mouseto Start Animation NaHCO3 NH3Cl- H + NH4Cl Click Mouse to See Animation Again Notice the H+ - Na+ exchange to maintain electrical neutrality ACIDIFICATION OF URINE BY EXCRETION OFACIDIFICATION OF URINE BY EXCRETION OF AMMONIAAMMONIA
- 210. 210 RESPIRATORY / EXCRETORYRESPIRATORY/ EXCRETORY RESPONSERESPONSE COCO22 + H+ H22 O HO H22 COCO33 HH++ + HCO+ HCO33 yperventilation removes HH++ ion concentrations ypoventilation increases HH++ ion concentrations Kidneys eliminate or retai HH++ or bicarbonate ions
- 211. 211 1)1) Buffer SystemsBufferSystems 2) Respiratory Responses2) Respiratory Responses 3) Renal Responses3) Renal Responses 4) Intracellular Shifts of4) Intracellular Shifts of IonsIons
- 212. 212 HYPERKALEMIAHYPERKALEMIA ♥HyperkalemiaHyperkalemia is generallyassociated with acidosis ♠Accompanied by a shift of H+ ions into cells and K+ ions out of the cell to maintain electrical neutrality H+ K+
- 213. 213 HYPERKALEMIAHYPERKALEMIA ♥Hyperkalemia is anelevated serum K+ ♠H+ ions are buffered in cell by proteins ♥Acidosis may cause Hyperkalemia and Hyperkalemia may cause Acidosis H+ K+
- 214. 214 HYPOKALEMIAHYPOKALEMIA ♥HypokalemiaHypokalemia is generallyassociated with reciprocal exchanges of H+ and K+ in the opposite direction ♠Associated with alkalosis ♥Hypokalemia is a depressed serum K+ H+ K+
- 215. 215 ELECTROLYTE SHIFTSELECTROLYTE SHIFTS cell HH++ KK++ AcidosisAcidosis CompensatoryResponse Result - HH++ buffered intracellularly - Hyperkalemia HH++ KK++ cell AlkalosisAlkalosis Compensatory Response Result - Tendency to correct alkalos - Hypokalemia
- 216. 216 ENDEND ACID - BASEACID- BASE BALANCEBALANCE