acid-base balance

ADVANCED PHYSIOLOGY ACID BASE BALANCE: 

ADVANCED PHYSIOLOGY ACID BASE BALANCE

ACID BASE HOMEOSTASIS: 

2 ACID BASE HOMEOSTASIS Acid-Base homeostasis involves chemical and physiologic processes responsible for the maintenance of the acidity of body fluids at levels that allow optimal function of the whole individual

ACID BASE HOMEOSTASIS: 

3 ACID BASE HOMEOSTASIS The chemical processes represent the first line of defense to an acid or base load and include the extracellular and intracellular buffers The physiologic processes modulate acid-base composition by changes in cellular metabolism and by adaptive responses in the excretion of volatile acids by the lungs and fixed acids by the kidneys

ACID-BASE HOMEOSTASIS: 

4 ACID-BASE HOMEOSTASIS Acids Bases Acids Acids = Bases Acids > Bases Acids < Bases Acids Buffers

ACID BASE HOMEOSTASIS: 

5 ACID BASE HOMEOSTASIS The need for the existence of multiple mechanisms involved in Acid-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

ACID BASE HOMEOSTASIS: 

6 ACID BASE HOMEOSTASIS The task imposed on the mechanisms that maintain Acid-Base homeostasis is large Metabolic pathways are continuously consuming or producing H + The daily load of waste products for excretion in the form of volatile and fixed acids is substantial

EFFECTS OF pH: 

7 EFFECTS OF pH The most general effect of pH changes are on enzyme function Also affect excitability of nerve and muscle cells pH pH Excitability Excitability

ACID-BASE BALANCE: 

8 ACID-BASE BALANCE

ACID-BASE BALANCE: 

9 ACID-BASE BALANCE Acid - Base balance is primarily concerned with two ions: Hydrogen (H + ) Bicarbonate (HCO 3 - ) H + HCO 3 -

ACID-BASE BALANCE: 

10 ACID-BASE BALANCE Derangements of hydrogen and bicarbonate concentrations in body fluids are common in disease processes

ACID-BASE BALANCE: 

11 ACID-BASE BALANCE H + ion has special significance because of the narrow ranges that it must be maintained in order to be compatible with living systems

ACID-BASE BALANCE: 

12 ACID-BASE BALANCE Primarily controlled by regulation of H + ions in the body fluids Especially extracellular fluids

ACID-BASE REGULATION: 

13 ACID-BASE REGULATION

ACID-BASE REGULATION: 

14 ACID-BASE REGULATION Maintenance of an acceptable pH range in the extracellular fluids is accomplished by three mechanisms: 1) Chemical Buffers React very rapidly (less than a second) 2) Respiratory Regulation Reacts rapidly (seconds to minutes) 3) Renal Regulation Reacts slowly (minutes to hours)

ACID-BASE REGULATION: 

15 ACID-BASE REGULATION Chemical 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 H + OH - H + H + OH - OH - Buffer

ACID-BASE REGULATION: 

16 ACID-BASE REGULATION Respiratory 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 2 CO 2 Cell Metabolism

ACID-BASE REGULATION: 

17 ACID-BASE REGULATION Respiratory Regulation When breathing is increased, the blood carbon dioxide level decreases and the blood becomes more Base When breathing is decreased, the blood carbon dioxide level increases and the blood becomes more Acidic By adjusting the speed and depth of breathing, the respiratory control centers and lungs are able to regulate the blood pH minute by minute

ACID-BASE REGULATION: 

18 ACID-BASE REGULATION Kidney 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

ACID-BASE REGULATION: 

19 ACID-BASE REGULATION Enzymes, hormones and ion distribution are all affected by Hydrogen ion concentrations

ACIDS: 

20 ACIDS

ACIDS: 

21 ACIDS Acids can be defined as a proton ( H + ) donor Hydrogen containing substances which dissociate in solution to release H +

ACIDS: 

22 ACIDS Acids can be defined as a proton ( H + ) donor Hydrogen containing substances which dissociate in solution to release H + Click Here

ACIDS: 

23 ACIDS Acids can be defined as a proton ( H + ) donor Hydrogen containing substances which dissociate in solution to release H + H+ OH- H+ OH- H+ OH- H+ OH-

ACIDS: 

24 ACIDS 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 H + H+ OH- H+ OH- H+ OH- H+ OH-

ACIDS: 

25 ACIDS Physiologically important acids include: Carbonic acid (H 2 CO 3 ) Phosphoric acid (H 3 PO 4 ) Pyruvic acid (C 3 H 4 O 3 ) Lactic acid (C 3 H 6 O 3 ) These acids are dissolved in body fluids Lactic acid Pyruvic acid Carbonic acid Phosphoric acid

BASES: 

26 BASES

BASES: 

27 BASES Bases can be defined as: A proton ( H + ) acceptor Molecules capable of accepting a hydrogen ion ( OH - ) Click Here

BASES: 

28 BASES Bases can be defined as: A proton ( H + ) acceptor Molecules capable of accepting a hydrogen ion ( OH - ) Click Here

BASES: 

29 BASES Bases can be defined as: A proton ( H + ) acceptor Molecules capable of accepting a hydrogen ion ( OH - ) H+ OH- H+ OH- H+ OH- H+ OH-

BASES: 

30 BASES Physiologically important bases include: Bicarbonate (HCO 3 - ) Biphosphate (HPO 4 -2 ) Biphosphate Bicarbonate

pH SCALE: 

31 pH SCALE

pH SCALE: 

32 pH refers to P otential H ydrogen Expresses hydrogen ion concentration in water solutions Water ionizes to a limited extent to form equal amounts of H + ions and OH - ions H 2 O H + + OH - H + ion is an acid OH - ion is a base pH SCALE

pH SCALE: 

33 H + ion is an acid pH SCALE

pH SCALE: 

34 OH - ion is a base pH SCALE

pH SCALE: 

35 H + ion is an acid OH - ion is a base pH SCALE

pH SCALE: 

36 Pure water is Neutral ( H + = OH - ) pH = 7 Acid ( H + > OH - ) pH < 7 Base ( H + < OH - ) pH > 7 Normal blood pH is 7.35 - 7.45 pH range compatible with life is 6.8 - 8.0 pH 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??? 1 2 3

pH SCALE: 

37 pH SCALE pH equals the logarithm (log) to the base 10 of the reciprocal of the hydrogen ion ( H + ) concentration H + concentration in extracellular fluid (ECF) pH = log 1 / H + concentration 4 X 10 -8 (0.00000004)

pH SCALE: 

38 pH SCALE Low pH values = high H + concentrations H + concentration in denominator of formula Unit changes in pH represent a tenfold change in H + concentrations Nature of logarithms pH = log 1 / H + concentration 4 X 10 -8 (0.00000004)

pH SCALE: 

39 pH SCALE pH = 4 is more acidic than pH = 6 pH = 4 has 10 times more free H + concentration than pH = 5 and 100 times more free H + concentration than pH = 6 ACIDOSIS ALKALOSIS NORMAL DEATH DEATH Venous Blood Arterial Blood 7.3 7.5 7.4 6.8 8.0

pH SCALE: 

40 pH SCALE

pH SCALE: 

41 pH SCALE

ACIDOSIS / ALKALOSIS: 

42 ACIDOSIS / ALKALOSIS

ACIDOSIS / ALKALOSIS: 

43 ACIDOSIS / ALKALOSIS An abnormality in one or more of the pH control mechanisms can cause one of two major disturbances in Acid-Base balance Acidosis Alkalosis

ACIDOSIS / ALKALOSIS: 

44 ACIDOSIS / ALKALOSIS Acidosis A condition in which the blood has too much acid (or too little base), frequently resulting in a decrease in blood pH Alkalosis A condition in which the blood has too much base (or too little acid), occasionally resulting in an increase in blood pH

ACIDOSIS / ALKALOSIS: 

45 ACIDOSIS / 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

ACIDOSIS / ALKALOSIS: 

46 ACIDOSIS / ALKALOSIS pH changes have dramatic effects on normal cell function 1) Changes in excitability of nerve and muscle cells 2) Influences enzyme activity 3) Influences K + levels

CHANGES IN CELL EXCITABILITY: 

47 CHANGES IN CELL EXCITABILITY 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

INFLUENCES ON ENZYME ACTIVITY: 

48 INFLUENCES ON ENZYME ACTIVITY 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

INFLUENCES ON K+ LEVELS: 

49 INFLUENCES ON K + LEVELS When reabsorbing Na + from the filtrate of the renal tubules K + or H + is secreted (exchanged) Normally K + is secreted in much greater amounts than H + K + K + K + K + K + K + K + Na + Na + Na + Na + Na + Na + H +

INFLUENCES ON K+ LEVELS: 

50 INFLUENCES ON K + LEVELS If H + concentrations are high (acidosis) than H + is secreted in greater amounts This leaves less K + than usual excreted The resultant K + 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 +

ACIDOSIS: 

51 A relative increase in hydrogen ions results in acidosis ACIDOSIS H + OH -

ALKALOSIS: 

52 A relative increase in bicarbonate results in alkalosis ALKALOSIS H + OH -

ACIDOSIS / ALKALOSIS: 

53 Alkalosis ACIDOSIS / ALKALOSIS H + OH - Acidosis H + OH -

ACIDOSIS / ALKALOSIS: 

54 Normal ratio of HCO 3 - to H 2 CO 3 is 20:1 H 2 CO 3 is source of H + ions in the body Deviations from this ratio are used to identify Acid-Base imbalances ACIDOSIS / ALKALOSIS BASE ACID H 2 CO 3 H + HCO 3 -

ACIDOSIS / ALKALOSIS: 

55 ACIDOSIS / ALKALOSIS Acidosis and Alkalosis can arise in two fundamentally different ways: 1) Excess or deficit of CO 2 ( Volatile Acid ) Volatile Acid can be eliminated by the respiratory system 2) Excess or deficit of Fixed Acid Fixed Acids cannot be eliminated by the respiratory system

ACIDOSIS / ALKALOSIS: 

56 ACIDOSIS / ALKALOSIS Normal values of bicarbonate (arterial) pH = 7.4 PCO 2 = 40 mm Hg HCO 3 - = 24 meq/L

ACIDOSIS: 

57 ACIDOSIS A decrease in a 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 ACID BASE

ALKALOSIS: 

58 ALKALOSIS An increase in the 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 ACID BASE

SOURCES OF HYDROGEN IONS : 

59 SOURCES OF HYDROGEN IONS C C C C C C H H H H H H H H H H H H

SOURCES OF HYDROGEN IONS : 

60 SOURCES OF HYDROGEN IONS 1) Cell Metabolism (CO 2 ) 2) Food Products 3) Medications 4) Metabolic Intermediate by-products 5) Some Disease processes

SOURCES OF HYDROGEN IONS: 

61 SOURCES OF HYDROGEN IONS 1) Cellular Metabolism of carbohydrates release CO 2 as a waste product Aerobic respiration C 6 H 12 O 6  CO 2 + H 2 O + Energy

SOURCES OF HYDROGEN IONS: 

62 SOURCES OF HYDROGEN IONS CO 2 diffuses into the bloodstream where the reaction: CO 2 + H 2 O H 2 CO 3 H + + HCO 3 - This process occurs in red blood cells H 2 CO 3 (carbonic acid) Acids produced as a result of the presence of CO 2 is referred to as a Volatile acid

SOURCES OF HYDROGEN IONS: 

63 SOURCES OF HYDROGEN IONS Dissociation of H 2 CO 3 results in the production of free H + and HCO 3 - The respiratory system removes CO 2 thus freeing HCO 3 - to recombine with H + Accumulation or deficit of CO 2 in blood leads to respective H + accumulations or deficits CO 2 H + CO 2 H + pH pH

CARBON DIOXIDE DIFFUSION: 

64 CARBON DIOXIDE DIFFUSION CO 2 CO 2 Red Blood Cell Systemic Circulation CO 2 H 2 O H + HCO 3 - + + HCO 3 - Cl - (Chloride Shift) CO 2 diffuses into plasma and into RBC Within RBC, the hydration of CO 2 is catalyzed by carbonic anhydrase Bicarbonate thus formed diffuses into plasma carbonic anhydrase Tissues Plasma

CARBON DIOXIDE DIFFUSION: 

65 CARBON DIOXIDE DIFFUSION CO 2 Red Blood Cell Systemic Circulation H 2 O H + HCO 3 - carbonic anhydrase Plasma CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 Click for Carbon Dioxide diffusion + + Tissues H + Cl - Hb H + is buffered by Hemoglobin

SOURCES OF HYDROGEN IONS : 

66 SOURCES OF HYDROGEN IONS 3) Medications May stimulate HCl production by parietal cells of the stomach

SOURCES OF HYDROGEN IONS : 

67 SOURCES OF HYDROGEN IONS 4) Metabolic Intermediate by-products Lactic acid Pyruvic acid Acetoacetic acid Fatty acids C 6 H 12 O 6 2 C 3 H 6 O 3

SOURCES OF HYDROGEN IONS : 

68 SOURCES OF HYDROGEN IONS Inorganic acids can also be produced during breakdown of nutrients Proteins (meat products) Breakdown leads to productions of sulfuric acid and phosphoric acid Fruits and Vegetables Breakdown produces bases which can help to equalize acid production

SOURCES OF HYDROGEN IONS : 

69 SOURCES OF HYDROGEN IONS 5) Some disease processes Ex: diabetes causes improper metabolism of fats which results in the generation of a waste product called a Keto Acid

SOURCES OF BICARBONATE IONS: 

70 SOURCES OF BICARBONATE IONS

SOURCES OF BICARBONATE IONS: 

71 SOURCES OF BICARBONATE IONS 1) CO 2 diffusion into red blood cells 2) Parietal cell secretion of the gastric mucosa

1) CO2 DIFFUSION: 

72 1) CO 2 DIFFUSION 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 -

PowerPoint Presentation: 

73 CARBON DIOXIDE DIFFUSION CO 2 CO 2 Red Blood Cell Systemic Circulation CO 2 H 2 O H + HCO 3 - + + HCO 3 - Cl - (Chloride Shift) CO 2 diffuses into the plasma and into the RBC Within the RBC, the hydration of CO 2 is catalyzed by carbonic anhydrase Bicarbonate thus formed diffuses into plasma carbonic anhydrase Tissues Plasma

BICARBONATE DIFFUSION: 

74 BICARBONATE DIFFUSION Red Blood Cell Pulmonary Circulation CO 2 H 2 O H + HCO 3 - + + HCO 3 - Cl - Alveolus Plasma CO 2 Bicarbonate diffuses back into RBC in pulmonary capillaries and reacts with hydrogen ions to form carbonic acid The acid breaks down to CO 2 and water

BICARBONATE DIFFUSION: 

75 BICARBONATE DIFFUSION Red Blood Cell Pulmonary Circulation CO 2 H 2 O H + + + HCO 3 - Cl - Alveolus Plasma CO 2 CO 2 H 2 O

2) PARIETAL CELL SECRETION: 

76 2) PARIETAL CELL SECRETION Bicarbonate ions diffuse into the bloodstream to maintain electrical neutrality in the parietal cell Blood Lumen of Stomach Parietal Cells H + Cl - HCO 3 - HCl Click to see ion movement CO 2 + H 2 O Secrete hydrogen ions into the lumen of the stomach

PANCREATIC CELL SECRETION: 

77 PANCREATIC CELL SECRETION Blood Pancreatic duct Pancreatic Cells H + HCO 3 - Click to 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 HCO 3 -

PARIETAL CELL SECRETION: 

78 PARIETAL CELL 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 HCO 3 - HCO 3 - HCO 3 - HCO 3 - HCO 3 - HCO 3 -

BICARBONATE SECRETION: 

79 Cells of the gastric 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 SECRETION Parietal cells of gastric mucosa Pancreatic epithelial cells HCO 3 - H + HCO 3 - H + lumen of stomach pancreatic juice blood blood

ACIDOSIS / ALKALOSIS: 

80 ACIDOSIS / ALKALOSIS

ACIDOSIS / ALKALOSIS: 

81 ACIDOSIS / ALKALOSIS Deviations from normal Acid-Base status are divided into four general categories, depending on the source and direction of the abnormal change in H + concentrations Respiratory Acidosis Respiratory Alkalosis Metabolic Acidosis Metabolic Alkalosis

ACIDOSIS / ALKALOSIS: 

82 ACIDOSIS / ALKALOSIS Acidosis and Alkalosis are categorized as Metabolic or Respiratory depending on their primary cause Metabolic Acidosis and Metabolic Alkalosis 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

ACIDOSIS: 

83 ACIDOSIS A pH of 7.4 corresponds to a 20:1 ratio of HCO 3 - and H 2 CO 3 Concentration of HCO 3 - is 24 meq/liter and H 2 CO 3 is 1.2 meq/liter Bicarbonate Carbonic Acid Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate Bicarbonate 7.4

ACIDOSIS: 

84 ACIDOSIS Acidosis is a decrease in pH below 7.35 Which means a relative increase of H + ions pH may fall as low as 7.0 without irreversible damage but any fall less than 7.0 is usually fatal H + pH =

ACIDOSIS : 

85 ACIDOSIS May be caused by: An increase in H 2 CO 3 A decrease in HCO 3 - Both lead to a decrease in the ratio of 20:1 H 2 CO 3 HCO 3 -

ACIDOSIS: 

86 ACIDOSIS 1) Respiratory Acidosis 2) 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 +

ALKALOSIS: 

87 H + H + H + H + H + H + H + H + H + H + H + H + H + H + H + H + 1) Respiratory alkalosis 2) Metabolic alkalosis ALKALOSIS

RESPIRATORY ACIDOSIS: 

88 RESPIRATORY ACIDOSIS

RESPIRATORY ACIDOSIS: 

89 RESPIRATORY ACIDOSIS Caused by hyperkapnia due to hypoventilation Characterized by a pH decrease and an increase in CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 pH pH

HYPOVENTILATION: 

90 HYPOVENTILATION Hypo = “Under” Elimination of CO 2 H + pH

RESPIRATORY ACIDOSIS: 

91 RESPIRATORY ACIDOSIS Hyperkapnia is defined as an accumulation of carbon dioxide in extracellular fluids CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 pH pH

RESPIRATORY ACIDOSIS: 

92 RESPIRATORY ACIDOSIS Hyperkapnia is the underlying cause of Respiratory Acidosis Usually the result of decreased CO 2 removal from the lungs CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 pH pH

RESPIRATORY ACIDOSIS: 

93 RESPIRATORY ACIDOSIS The speed and depth of breathing control the amount of CO 2 in the blood Normally when CO 2 builds up, the pH of the blood falls and the blood becomes acidic High levels of CO 2 in the blood stimulate the parts of the brain that regulate breathing, which in turn stimulate faster and deeper breathing

RESPIRATORY ACIDOSIS: 

94 RESPIRATORY ACIDOSIS Respiratory acidosis develops when the lungs don't expel CO 2 adequately This can happen in diseases that severely affect the lungs, such as emphysema, chronic bronchitis, severe pneumonia, pulmonary edema, and asthma

RESPIRATORY ACIDOSIS: 

95 RESPIRATORY ACIDOSIS Respiratory acidosis 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

RESPIRATORY ACIDOSIS: 

96 RESPIRATORY ACIDOSIS The treatment 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

RESPIRATORY ACIDOSIS: 

97 RESPIRATORY ACIDOSIS Decreased CO 2 removal can be the result of: Obstruction of air passages Decreased respiration (depression of respiratory centers) Decreased gas exchange between pulmonary capillaries and air sacs of lungs Collapse of lung

RESPIRATORY ACIDOSIS: 

98 RESPIRATORY ACIDOSIS 1) Obstruction of air passages Vomit, anaphylaxis, tracheal cancer

RESPIRATORY ACIDOSIS: 

99 RESPIRATORY ACIDOSIS 2) Decreased Respiration Shallow, slow breathing Depression of the respiratory centers in the brain which control breathing rates Drug overdose

RESPIRATORY ACIDOSIS: 

100 RESPIRATORY ACIDOSIS 3) Decreased gas exchange between pulmonary capillaries and air sacs of lungs Emphysema Bronchitis Pulmonary edema

RESPIRATORY ACIDOSIS: 

101 RESPIRATORY ACIDOSIS 4) Collapse of lung Compression injury, open thoracic wound Left lung collapsed

RESPIRATORY ACIDOSIS: 

102 RESPIRATORY ACIDOSIS metabolic balance before onset of acidosis pH = 7.4 respiratory acidosis pH = 7.1 breathing is suppressed holding CO 2 in body body’s compensation kidneys conserve HCO 3 - 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

RESPIRATORY ACIDOSIS: 

103 RESPIRATORY ACIDOSIS - metabolic balance before onset of acidosis - pH = 7.4 H 2 CO 3 HCO 3 - 1 20 : H 2 CO 3 : Carbonic Acid HCO 3 - : Bicarbonate Ion (Na + ) HCO 3 - (K + ) HCO 3 - (Mg ++ ) HCO 3 - (Ca ++ ) HCO 3 -

RESPIRATORY ACIDOSIS: 

104 RESPIRATORY ACIDOSIS breathing is suppressed holding CO 2 in body pH = 7.1 H 2 CO 3 HCO 3 - 2 20 : CO 2 CO 2 CO 2 CO 2

RESPIRATORY ACIDOSIS: 

105 RESPIRATORY ACIDOSIS BODY’S COMPENSATION kidneys conserve HCO 3 - ions to restore the normal 40:2 ratio (20:1) kidneys eliminate H + ion in acidic urine H 2 CO 3 HCO 3 - 2 30 : HCO 3 - H 2 CO 3 HCO 3 - H + + acidic urine

RESPIRATORY ACIDOSIS: 

106 RESPIRATORY ACIDOSIS - therapy required to restore metabolic balance - lactate solution used in therapy is converted to bicarbonate ions in the liver H 2 CO 3 HCO 3 - 2 40 : Lactate Lactate LIVER HCO 3 -

RESPIRATORY ALKALOSIS: 

107 RESPIRATORY ALKALOSIS

RESPIRATORY ALKALOSIS: 

108 RESPIRATORY ALKALOSIS Normal 20:1 ratio is increased pH of blood is above 7.4 H 2 CO 3 HCO 3 - 1 20 : = 7.4 H 2 CO 3 HCO 3 - 0.5 20 : = 7.4

RESPIRATORY ALKALOSIS: 

109 RESPIRATORY ALKALOSIS Cause is Hyperventilation Leads to eliminating excessive amounts of CO 2 Increased loss of CO 2 from the lungs at a rate faster than it is produced Decrease in H + CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2

HYPERVENTILATION: 

110 HYPERVENTILATION Hyper = “Over” Elimination of CO 2 H + pH

RESPIRATORY ALKALOSIS: 

111 RESPIRATORY ALKALOSIS Can be the result of: 1) Anxiety, emotional disturbances 2) Respiratory center lesions 3) Fever 4) Salicylate poisoning (overdose) 5) Assisted respiration 6) High altitude (low P O 2 )

RESPIRATORY ALKALOSIS: 

112 RESPIRATORY ALKALOSIS Anxiety is an emotional disturbance The most common cause of hyperventilation, and thus respiratory alkalosis, is anxiety

RESPIRATORY ALKALOSIS: 

113 RESPIRATORY ALKALOSIS Usually the 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 CO 2 content as the person breathes carbon dioxide back in after breathing it out

RESPIRATORY ALKALOSIS: 

114 RESPIRATORY ALKALOSIS Respiratory center lesions Damage to brain centers responsible for monitoring breathing rates Tumors Strokes

RESPIRATORY ALKALOSIS: 

115 RESPIRATORY ALKALOSIS F ever Rapid shallow breathing blows off too much CO 2

RESPIRATORY ALKALOSIS: 

116 RESPIRATORY ALKALOSIS Salicylate poisoning (Aspirin overdose) Ventilation is stimulated without regard to the status of O 2 , CO 2 or H + in the body fluids

RESPIRATORY ALKALOSIS: 

117 RESPIRATORY ALKALOSIS Assisted Respiration Administration of CO 2 in the exhaled air 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

RESPIRATORY ALKALOSIS: 

118 RESPIRATORY ALKALOSIS High Altitude Low concentrations of O 2 in the arterial blood reflexly stimulates ventilation in an attempt to obtain more O 2 Too much CO 2 is “blown off” in the process

RESPIRATORY ALKALOSIS: 

119 RESPIRATORY ALKALOSIS Kidneys compensate by: Retaining hydrogen ions Increasing bicarbonate excretion H + HCO 3 - HCO 3 - HCO 3 - HCO 3 - HCO 3 - HCO 3 - HCO 3 - HCO 3 - HCO 3 - HCO 3 - H + H + H + H + H + H + H + H + H + H +

RESPIRATORY ALKALOSIS: 

120 RESPIRATORY ALKALOSIS Decreased CO 2 in the lungs will eventually slow the rate of breathing Will permit a normal amount of CO 2 to be retained in the lung

RESPIRATORY ALKALOSIS: 

121 RESPIRATORY ALKALOSIS metabolic balance before onset of alkalosis pH = 7.4 respiratory alkalosis pH = 7.7 - hyperactive breathing “ blows off ” CO 2 - body’s compensation - kidneys conserve H + ions and eliminate HCO 3 - in alkaline urine - therapy required to restore metabolic balance - HCO 3 - ions replaced by Cl - ions

RESPIRATORY ALKALOSIS: 

122 RESPIRATORY ALKALOSIS metabolic balance before onset of alkalosis pH = 7.4 H 2 CO 3 HCO 3 - 1 20 : H 2 CO 3 : Carbonic Acid HCO 3 - : Bicarbonate Ion (Na + ) HCO 3 - (K + ) HCO 3 - (Mg ++ ) HCO 3 - (Ca ++ ) HCO 3 -

RESPIRATORY ALKALOSIS: 

123 RESPIRATORY ALKALOSIS respiratory alkalosis pH = 7.7 hyperactive breathing “ blows off ” CO 2 H 2 CO 3 HCO 3 - 0.5 20 : CO 2 CO 2 + H 2 O

RESPIRATORY ALKALOSIS: 

124 RESPIRATORY ALKALOSIS BODY’S COMPENSATION - kidneys conserve H + ions and eliminate HCO 3 - in alkaline urine H 2 CO 3 HCO 3 - 0.5 15 : HCO 3 - Alkaline Urine

RESPIRATORY ALKALOSIS: 

125 RESPIRATORY ALKALOSIS - therapy required to restore metabolic balance - HCO 3 - ions replaced by Cl - ions H 2 CO 3 HCO 3 - 0.5 10 : Cl - Chloride containing solution

RESPIRATORY ACIDOSIS / ALKALOSIS: 

126 RESPIRATORY ACIDOSIS / ALKALOSIS CO 2 + H 2 O H 2 CO 3 H + + HCO 3 - Respiratory Acidosis Respiratory Alkalosis

METABOLIC ACIDOSIS: 

127 METABOLIC ACIDOSIS

METABOLIC ACIDOSIS: 

128 METABOLIC ACIDOSIS Occurs when there is a decrease in the normal 20:1 ratio Decrease in blood pH and bicarbonate level Excessive H + or decreased HCO 3 - H 2 CO 3 HCO 3 - 1 20 : = 7.4 H 2 CO 3 HCO 3 - 1 10 : = 7.4

METABOLIC ACIDOSIS: 

129 METABOLIC ACIDOSIS Any acid-base imbalance not attributable to CO 2 is classified as metabolic Metabolic production of Acids Or loss of Bases

METABOLIC ACIDOSIS: 

130 METABOLIC ACIDOSIS If an increase in acid overwhelms the body's pH buffering system, the blood can become acidic As the blood pH drops, breathing becomes deeper and faster as the body attempts to rid the blood of excess acid by decreasing the amount of carbon dioxide

METABOLIC ACIDOSIS: 

131 METABOLIC 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

METABOLIC ACIDOSIS: 

132 METABOLIC ACIDOSIS Metabolic acidosis is always characterized by a reduction in plasma HCO 3 - while CO 2 remains normal HCO 3 - CO 2 Plasma Levels

METABOLIC ACIDOSIS: 

133 METABOLIC ACIDOSIS Acidosis results from excessive loss of HCO 3 - rich fluids from the body or from an accumulation of acids Accumulation of non-carbonic plasma acids uses HCO 3 - as a buffer for the additional H + thus reducing HCO 3 - levels Lactic Acid Muscle Cell HCO 3 -

METABOLIC ACIDOSIS: 

134 METABOLIC ACIDOSIS The causes of metabolic acidosis can be grouped into five major categories 1) Ingesting an acid or a substance that is metabolized to acid 2) Abnormal Metabolism 3) Kidney Insufficiencies 4) Strenuous Exercise 5) Severe Diarrhea

METABOLIC ACIDOSIS: 

135 METABOLIC ACIDOSIS 1) 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

METABOLIC ACIDOSIS: 

136 METABOLIC ACIDOSIS 2) Abnormal Metabolism The body can produce excess acid as a result of several diseases One of the most significant is Type I Diabetes Mellitus

METABOLIC ACIDOSIS: 

137 METABOLIC ACIDOSIS Unregulated diabetes mellitus causes ketoacidosis Body metabolizes fat rather than glucose Accumulations of metabolic acids (Keto Acids) cause an increase in plasma H +

METABOLIC ACIDOSIS: 

138 METABOLIC ACIDOSIS This leads to excessive production of ketones: Acetone Acetoacetic acid B-hydroxybutyric acid Contribute excessive numbers of hydrogen ions to body fluids Acetone Acetoacetic acid Hydroxybutyric acid H + H + H + H + H + H + H +

METABOLIC ACIDOSIS: 

139 METABOLIC ACIDOSIS 2) Abnormal Metabolism The body also produces excess acid in the advanced stages of shock, when lactic acid is formed through the metabolism of sugar

METABOLIC ACIDOSIS: 

140 METABOLIC ACIDOSIS 3) Kidney Insufficiencies Even the production of normal amounts of acid may lead to acidosis when the kidneys aren't functioning normally

METABOLIC ACIDOSIS: 

141 METABOLIC ACIDOSIS 3) Kidney Insufficiencies Kidneys may be unable to rid the plasma of even the normal amounts of H + generated from metabolic acids Kidneys may be also unable to conserve an adequate amount of HCO 3 - to buffer the normal acid load

METABOLIC ACIDOSIS: 

142 METABOLIC ACIDOSIS 3) Kidney Insufficiencies This type of kidney malfunction is called renal tubular acidosis or uremic acidosis and may occur in people with kidney failure or with abnormalities that affect the kidneys' ability to excrete acid

METABOLIC ACIDOSIS: 

143 METABOLIC ACIDOSIS 4) Strenuous Exercise Muscles resort to anaerobic glycolysis during strenuous exercise Anaerobic respiration leads to the production of large amounts of lactic acid C 6 H 12 O 6 2C 3 H 6 O 3 + ATP (energy) Enzymes Lactic Acid

METABOLIC ACIDOSIS: 

144 METABOLIC ACIDOSIS 5) Severe Diarrhea Fluids rich in HCO 3 - are released and reabsorbed during the digestive process During diarrhea this HCO 3 - is lost from the body rather than reabsorbed

METABOLIC ACIDOSIS: 

145 METABOLIC ACIDOSIS 5) Severe Diarrhea The loss of HCO 3 - without a corresponding loss of H + lowers the pH Less HCO 3 - is available for buffering H + Prolonged deep (from duodenum) vomiting can result in the same situation

METABOLIC ACIDOSIS: 

146 METABOLIC ACIDOSIS Treating the 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

METABOLIC ACIDOSIS: 

147 METABOLIC ACIDOSIS Metabolic acidosis may also be treated directly If the acidosis is mild, intravenous fluids and treatment for the underlying disorder may be all that's needed

METABOLIC ACIDOSIS: 

148 METABOLIC ACIDOSIS When acidosis is severe, bicarbonate may be given intravenously Bicarbonate provides only temporary relief and may cause harm

METABOLIC ACIDOSIS: 

149 METABOLIC ACIDOSIS - metabolic balance before onset of acidosis - pH 7.4 metabolic acidosis pH 7.1 - HCO 3 - decreases because of excess presence of ketones, chloride or organic ions - body’s compensation - hyperactive breathing to “ blow off ” CO 2 - kidneys conserve HCO 3 - and eliminate H + ions in acidic urine - therapy required to restore metabolic balance - lactate solution used in therapy is converted to bicarbonate ions in the liver 0.5 10

METABOLIC ACIDOSIS: 

150 METABOLIC ACIDOSIS metabolic balance before onset of acidosis pH 7.4 H 2 CO 3 : Carbonic Acid HCO 3 - : Bicarbonate Ion (Na + ) HCO 3 - (K + ) HCO 3 - (Mg ++ ) HCO 3 - (Ca ++ ) HCO 3 - H 2 CO 3 HCO 3 - 1 20 :

METABOLIC ACIDOSIS: 

151 METABOLIC ACIDOSIS HCO 3 - decreases because of excess presence of ketones, chloride or organic ions pH 7.1 H 2 CO 3 HCO 3 - 1 10 : = 7.4

METABOLIC ACIDOSIS: 

152 METABOLIC ACIDOSIS BODY’S COMPENSATION - hyperactive breathing to “ blow off ” CO 2 - kidneys conserve HCO 3 - and eliminate H + ions in acidic urine H 2 CO 3 HCO 3 - 0.75 10 : CO 2 CO 2 + H 2 O HCO 3 - + H + HCO 3 - + H + Acidic urine

METABOLIC ACIDOSIS: 

153 METABOLIC ACIDOSIS - therapy required to restore metabolic balance - lactate solution used in therapy is converted to bicarbonate ions in the liver H 2 CO 3 HCO 3 - 0.5 10 : Lactate Lactate containing solution

METABOLIC ALKALOSIS: 

154 METABOLIC ALKALOSIS

METABOLIC ALKALOSIS: 

155 METABOLIC ALKALOSIS Elevation of pH 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 CO 2 Increase in pH which has a non-respiratory origin 7.4

METABOLIC ALKALOSIS: 

156 METABOLIC ALKALOSIS A reduction in H + in the case of metabolic alkalosis can be caused by a deficiency of non-carbonic acids This is associated with an increase in HCO 3 -

METABOLIC ALKALOSIS: 

157 METABOLIC ALKALOSIS Treatment of metabolic alkalosis is most often accomplished by replacing water and electrolytes ( sodium and potassium ) while treating the underlying cause Occasionally when metabolic alkalosis is very severe, dilute acid in the form of ammonium chloride is given by IV

METABOLIC ALKALOSIS: 

158 METABOLIC ALKALOSIS Can be the result of: 1) Ingestion of Alkaline Substances 2) Vomiting ( loss of HCl )

METABOLIC ALKALOSIS: 

159 METABOLIC ALKALOSIS 1) Ingestion of Alkaline Substances Influx of NaHCO 3

METABOLIC ALKALOSIS: 

160 METABOLIC ALKALOSIS Baking soda ( NaHCO 3 ) often used as a remedy for gastric hyperacidity NaHCO 3 dissociates to Na + and HCO 3 -

METABOLIC ALKALOSIS: 

161 METABOLIC ALKALOSIS Bicarbonate neutralizes high acidity in stomach (heart burn) The extra bicarbonate is absorbed into the plasma increasing pH of plasma as bicarbonate binds with free H +

METABOLIC ALKALOSIS: 

162 METABOLIC ALKALOSIS Commercially prepared alkaline products for gastric hyperacidity are not absorbed from the digestive tract and do not alter the pH status of the plasma

METABOLIC ALKALOSIS: 

163 METABOLIC ALKALOSIS 2) Vomiting (abnormal loss of HCl) Excessive loss of H +

METABOLIC ALKALOSIS: 

164 METABOLIC ALKALOSIS Gastric juices contain large amounts of HCl During HCl secretion, bicarbonate is added to the plasma K + H + Cl - HCO 3 - HCl Click to View Animation

METABOLIC ALKALOSIS: 

165 HCl METABOLIC ALKALOSIS K + H + Cl - HCO 3 - Click to View Animation The bicarbonate is neutralized as HCl is reabsorbed by the plasma from the digestive tract H 2 CO 3

METABOLIC ALKALOSIS: 

166 METABOLIC ALKALOSIS HCl K + HCO 3 - Click to View Animation During vomiting H + is lost as HCl and the bicarbonate is not neutralized in the plasma Loss of HCl increases the plasma bicarbonate and thus results in an increase in pH of the blood Bicarbonate not neutralized

METABOLIC ALKALOSIS : 

167 METABOLIC ALKALOSIS Reaction of the body to alkalosis is to lower pH by: Retain CO 2 by decreasing breathing rate Kidneys increase the retention of H + CO 2 CO 2 H + H + H + H +

METABOLIC ALKALOSIS: 

168 METABOLIC ALKALOSIS - metabolic balance before onset of alkalosis - pH = 7.4 metabolic alkalosis pH = 7.7 - HCO 3 - increases because of loss of chloride ions or excess ingestion of NaHCO 3 - body’s compensation - breathing suppressed to hold CO 2 - kidneys conserve H + ions and eliminate HCO 3 - in alkaline urine - therapy required to restore metabolic balance - HCO 3 - ions replaced by Cl - ions 1.25 25

METABOLIC ALKALOSIS: 

169 METABOLIC ALKALOSIS metabolic balance before onset of alkalosis pH = 7.4 H 2 CO 3 : Carbonic Acid HCO 3 - : Bicarbonate Ion (Na + ) HCO 3 - (K + ) HCO 3 - (Mg ++ ) HCO 3 - (Ca ++ ) HCO 3 - H 2 CO 3 HCO 3 - 1 20 :

METABOLIC ALKALOSIS: 

170 METABOLIC ALKALOSIS pH = 7.7 HCO 3 - increases because of loss of chloride ions or excess ingestion of NaHCO 3 HCO 3 - 1 40 : H 2 CO 3

METABOLIC ALKALOSIS: 

171 H 2 CO 3 HCO 3 - METABOLIC ALKALOSIS BODY’S COMPENSATION - breathing suppressed to hold CO 2 - kidneys conserve H + ions and eliminate HCO 3 - in alkaline urine 1.25 30 CO 2 + H 2 O HCO 3 - + H + HCO 3 - H + + Alkaline urine :

METABOLIC ALKALOSIS: 

172 METABOLIC ALKALOSIS - Therapy required to restore metabolic balance - HCO 3 - ions replaced by Cl - ions H 2 CO 3 HCO 3 - 1.25 25 : Cl - Chloride containing solution

ACIDOSIS: 

173 ACIDOSIS decreased removal of CO 2 from lungs failure of kidneys to excrete acids metabolic acid production of keto acids absorption of metabolic acids from GI tract prolonged diarrhea accumulation of CO 2 in blood accumulation of acid in blood excessive loss of NaHCO 3 from blood metabolic acidosis deep vomiting from GI tract kidney disease (uremia) increase in plasma H + concentration depression of nervous system accumulation of CO 2 in blood accumulation of acid in blood excessive loss of NaHCO 3 from blood respiratory acidosis

PowerPoint Presentation: 

174 ALKALOSIS respiratory alkalosis anxiety overdose of certain drugs high altitudes prolonged vomiting ingestion of excessive alkaline drugs excess aldosterone hyperventilation loss of CO 2 and H 2 CO 2 from blood loss of acid accumulation of base metabolic alkalosis decrease in plasma H + concentration overexcitability of nervous system hyperventilation loss of CO 2 and H 2 CO 2 from blood loss of acid accumulation of base

ACID – BASE DISORDERS: 

175 ACID – 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

RESPONSES TO: ACIDOSIS AND ALKALOSIS: 

176 RESPONSES TO: ACIDOSIS AND ALKALOSIS Mechanisms protect the body against life-threatening changes in hydrogen ion concentration 1) Buffering Systems in Body Fluids 2) Respiratory Responses 3) Renal Responses 4) Intracellular Shifts of Ions

Buffer Systems 2) Respiratory Responses 3) Renal Responses 4) Intracellular Shifts of Ions: 

177 Buffer Systems 2) Respiratory Responses 3) Renal Responses 4) Intracellular Shifts of Ions

BUFFERS: 

178 BUFFERS Buffering systems provide an immediate response to fluctuations in pH 1) Phosphate 2) Protein 3) Bicarbonate Buffer System

BUFFERS: 

179 BUFFERS A buffer is a combination of chemicals in solution that resists any significant change in pH Able to bind or release free H + ions

BUFFERS: 

180 BUFFERS Chemical buffers are able to react immediately (within milliseconds) Chemical buffers are the first line of defense for the body for fluctuations in pH

PHOSPHATE BUFFER SYSTEM: 

181 1) Phosphate buffer system Na 2 HPO 4 + H + NaH 2 PO 4 + Na + Most important in the intracellular system PHOSPHATE BUFFER SYSTEM H + Na 2 HPO 4 + NaH 2 PO 4 Click to animate Na + +

PHOSPHATE BUFFER SYSTEM: 

182 Na 2 HPO 4 + H + NaH 2 PO 4 + Na + Alternately switches Na + with H + PHOSPHATE BUFFER SYSTEM H + Na 2 HPO 4 + NaH 2 PO 4 Click to animate Na + + Disodium hydrogen phosphate

PHOSPHATE BUFFER SYSTEM: 

183 Na 2 HPO 4 + H + NaH 2 PO 4 + Na + Phosphates are more abundant within the cell and are rivaled as a buffer in the ICF by even more abundant protein PHOSPHATE BUFFER SYSTEM Na 2 HPO 4 Na 2 HPO 4 Na 2 HPO 4

PHOSPHATE BUFFER SYSTEM: 

184 Regulates pH within the 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 ECF buffer system PHOSPHATE BUFFER SYSTEM HPO 4 -2

PROTEIN BUFFER SYSTEM: 

185 PROTEIN BUFFER SYSTEM 2) Protein Buffer System Behaves as a buffer in both plasma and cells Hemoglobin is by far the most important protein buffer

PROTEIN BUFFER SYSTEM: 

186 PROTEIN BUFFER SYSTEM Most important intracellular buffer ( ICF ) The most plentiful buffer of the body

PROTEIN BUFFER SYSTEM: 

187 PROTEIN BUFFER SYSTEM Proteins are excellent buffers because they contain both acid and base groups that can give up or take up H + Proteins are extremely abundant in the cell The more limited number of proteins in the plasma reinforce the bicarbonate system in the ECF

PROTEIN BUFFER SYSTEM: 

188 PROTEIN BUFFER SYSTEM Hemoglobin buffers H + from metabolically produced CO 2 in the plasma only As hemoglobin releases O 2 it gains a great affinity for H + Hb O 2 O 2 O 2 O 2 H +

PROTEIN BUFFER SYSTEM: 

189 PROTEIN BUFFER SYSTEM H + generated at the tissue level from the dissociation of H 2 CO 3 produced by the addition of CO 2 Bound H + to Hb (Hemoglobin) does not contribute to the acidity of blood Hb O 2 O 2 O 2 O 2 H +

PROTEIN BUFFER SYSTEM: 

190 PROTEIN BUFFER SYSTEM As H + Hb picks up O 2 from the lungs the Hb which has a higher affinity for O 2 releases H + and picks up O 2 Liberated H + from H 2 O combines with HCO 3 - HCO 3 - H 2 CO 3 CO 2 (exhaled) Hb O 2 O 2 O 2 H + O 2

PROTEIN BUFFER SYSTEM: 

191 PROTEIN BUFFER SYSTEM Venous blood is only slightly more acidic than arterial blood because of the tremendous buffering capacity of Hb Even in spite of the large volume of H + generating CO 2 carried in venous blood

PROTEIN BUFFER SYSTEM: 

192 Pr - added H + + Pr - PROTEIN 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

PROTEIN BUFFER SYSTEM: 

193 PROTEIN BUFFER 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 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + + + + + + + + + + + + + + + + + + + + + + + + +

PROTEIN BUFFER SYSTEM: 

194 PROTEIN BUFFER 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 +

PROTEIN BUFFER SYSTEM: 

195 PROTEIN BUFFER 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 -

PROTEIN BUFFER SYSTEM: 

196 PROTEIN BUFFER 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 +

BICARBONATE BUFFER SYSTEM: 

197 BICARBONATE BUFFER SYSTEM 3) Bicarbonate Buffer System Predominates in extracellular fluid ( ECF ) HCO 3 - + added H + H 2 CO 3 H + HCO 3 - H 2 CO 3

BICARBONATE BUFFER SYSTEM: 

198 BICARBONATE BUFFER SYSTEM This system is most important because the concentration of both components can be regulated: Carbonic acid by the respiratory system Bicarbonate by the renal system

BICARBONATE BUFFER SYSTEM: 

199 BICARBONATE BUFFER SYSTEM H 2 CO 3 H + + HCO 3 - Hydrogen ions generated by metabolism or by ingestion react with bicarbonate base to form more carbonic acid H + HCO 3 - H 2 CO 3

BICARBONATE BUFFER SYSTEM: 

200 BICARBONATE BUFFER SYSTEM Equilibrium shifts toward the formation of acid Hydrogen ions that are lost (vomiting) causes carbonic acid to dissociate yielding replacement H + and bicarbonate H + HCO 3 - H 2 CO 3

BICARBONATE BUFFER SYSTEM: 

201 Loss of HCl Addition of lactic acid BICARBONATE BUFFER SYSTEM H + HCO 3 - H 2 CO 3 H 2 O CO 2 + + Exercise Vomiting

1) Buffer Systems 2) Respiratory Responses 3) Renal Responses 4) Intracellular Shifts of Ions: 

202 1) Buffer Systems 2) Respiratory Responses 3) Renal Responses 4) Intracellular Shifts of Ions

RESPIRATORY RESPONSE: 

203 RESPIRATORY RESPONSE Neurons in the medulla oblongata and pons constitute the Respiratory Center Stimulation and limitation of respiratory rates are controlled by the respiratory center Control is accomplished by responding to CO 2 and H + concentrations in the blood

RESPIRATORY CENTER: 

204 RESPIRATORY CENTER Respiratory centers Medulla oblongata Pons

CHEMOSENSITIVE AREAS: 

205 CHEMOSENSITIVE AREAS Chemosensitive areas of the respiratory center are able to detect blood concentration levels of CO 2 and H + Increases in CO 2 and H + stimulate the respiratory center The effect is to raise respiration rates But the effect diminishes in 1 - 2 minutes CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 CO 2 Click to increase CO 2

CHEMOSENSITIVE AREAS: 

206 CHEMOSENSITIVE AREAS The effect of stimulating the respiratory centers by increased CO 2 and H + is weakened in environmentally increased CO 2 levels Symptoms may persist for several days

CHEMORECEPTORS: 

207 CHEMORECEPTORS Chemoreceptors are also present in the carotid and aortic arteries which respond to changes in partial pressures of O 2 and CO 2 or pH Increased levels of CO 2 (low pH ) or decreased levels of O 2 stimulate respiration rates to increase

CHEMORECEPTORS: 

208 CHEMORECEPTORS Overall compensatory response is: Hyperventilation in response to increased CO 2 or H + (low pH ) Hypoventilation in response to decreased CO 2 or H + (high pH )

RESPIRATORY CONTROL OF pH: 

209 RESPIRATORY CONTROL OF pH pH rises toward normal rate and depth of breathing increase CO 2 eliminated in lungs H + stimulates respiratory center in medulla oblongata H 2 CO 3 H + + HCO 3 - H + acidosis; pH drops CO 2 + H 2 O H 2 CO 3 cell production of CO 2 increases

1) Buffer Systems 2) Respiratory Responses 3) Renal Responses 4) Intracellular Shifts of Ions: 

210 1) Buffer Systems 2) Respiratory Responses 3) Renal Responses 4) Intracellular Shifts of Ions

RENAL RESPONSE: 

211 RENAL RESPONSE The kidney compensates for Acid - Base imbalance within 24 hours and is responsible for long term control The kidney in response: To Acidosis Retains bicarbonate ions and eliminates hydrogen ions To Alkalosis Eliminates bicarbonate ions and retains hydrogen ions

ACIDIFICATION OF URINE BY EXCRETION OF AMMONIA: 

212 ACIDIFICATION OF URINE BY EXCRETION OF AMMONIA

ACIDIFICATION OF URINE BY EXCRETION OF AMMONIA: 

213 ACIDIFICATION OF URINE BY EXCRETION OF AMMONIA Capillary Distal Tubule Cells Tubular urine to be excreted NH 2 H + NH 3 NH 2 H + NH 3 WHAT HAPPENS NEXT?

ACIDIFICATION OF URINE BY EXCRETION OF AMMONIA: 

214 Capillary Distal Tubule Cells Tubular Urine NH 3 Na + Cl - + H 2 CO 3 HCO 3 - + NaCl NaHCO 3 Click Mouse to Start Animation NaHCO 3 NH 3 Cl - H + NH 4 Cl Click Mouse to See Animation Again Notice the H + - Na + exchange to maintain electrical neutrality ACIDIFICATION OF URINE BY EXCRETION OF AMMONIA Dissociation of carbonic acid

ACIDIFICATION OF URINE BY EXCRETION OF AMMONIA: 

215 Capillary Distal Tubule Cells Tubular Urine NH 3 Na + Cl - + H 2 CO 3 HCO 3 - + NaCl NaHCO 3 Click Mouse to Start Animation NaHCO 3 NH 3 Cl - H + NH 4 Cl Click Mouse to See Animation Again Notice the H + - Na + exchange to maintain electrical neutrality ACIDIFICATION OF URINE BY EXCRETION OF AMMONIA

RESPIRATORY / EXCRETORY RESPONSE: 

216 RESPIRATORY / EXCRETORY RESPONSE CO 2 + H 2 O H 2 CO 3 H + + HCO 3 - Hyperventilation removes H + ion concentrations Hypoventilation increases H + ion concentrations Kidneys eliminate or retain H + or bicarbonate ions

1) Buffer Systems 2) Respiratory Responses 3) Renal Responses 4) Intracellular Shifts of Ions: 

217 1) Buffer Systems 2) Respiratory Responses 3) Renal Responses 4) Intracellular Shifts of Ions

HYPERKALEMIA: 

218 HYPERKALEMIA Hyperkalemia is generally associated with acidosis Accompanied by a shift of H + ions into cells and K + ions out of the cell to maintain electrical neutrality H + K +

HYPERKALEMIA: 

219 HYPERKALEMIA Hyperkalemia is an elevated serum K + H + ions are buffered in cell by proteins Acidosis may cause Hyperkalemia and Hyperkalemia may cause Acidosis H + K +

HYPOKALEMIA: 

220 HYPOKALEMIA Hypokalemia is generally associated with reciprocal exchanges of H + and K + in the opposite direction Associated with alkalosis Hypokalemia is a depressed serum K + H + K +

ELECTROLYTE SHIFTS: 

221 ELECTROLYTE SHIFTS cell H + K + Acidosis Compensatory Response Result - H + buffered intracellularly - Hyperkalemia H + K + cell Alkalosis Compensatory Response Result - Tendency to correct alkalosis - Hypokalemia

END ACID - BASE BALANCE: 

222 END ACID - BASE BALANCE