3. ACID-BASE HOMEOSTASIS Acids Bases Acids Acids = Bases Acids > Bases Acids < Bases Acids Buffers

7. ACID-BASE BALANCE

12. ACID-BASE REGULATION

19. ACIDS

25. BASES

30. pH SCALE

39. pH SCALE

40. pH SCALE

41. ACIDOSIS / ALKALOSIS

58. SOURCES OF HYDROGEN IONS C C C C C C H H H H H H H H H H H H

63. CARBON DIOXIDE DIFFUSION CO 2 CO 2 Red Blood Cell Systemic Circulation 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 CO 2 H 2 O H + HCO 3 - + +

64. 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

70. SOURCES OF BICARBONATE IONS

73. CARBON DIOXIDE DIFFUSION CO 2 CO 2 Red Blood Cell Systemic Circulation 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 CO 2 H 2 O H + HCO 3 - + +

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

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

80. ACIDOSIS / ALKALOSIS

88. 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 -

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 -

107. RESPIRATORY ALKALOSIS

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

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

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

127. 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

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

154. METABOLIC ALKALOSIS

171. 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 : H 2 CO 3 HCO 3 -

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

173. ACIDOSIS deep vomiting from GI tract kidney disease (uremia) increase in plasma H + concentration depression of nervous system 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 accumulation of CO 2 in blood accumulation of acid in blood excessive loss of NaHCO 3 from blood respiratory acidosis

174. ALKALOSIS overexcitability of nervous system 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 hyperventilation loss of CO 2 and H 2 CO 2 from blood loss of acid accumulation of base

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

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 + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + + + + + + + + + + + + + + + + + + + + + + + + +

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

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

204. RESPIRATORY CENTER Respiratory centers Medulla oblongata Pons

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

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

212. 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?

214. ACIDIFICATION OF URINE BY EXCRETION OF AMMONIA 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 Dissociation of carbonic acid

215. ACIDIFICATION OF URINE BY EXCRETION OF AMMONIA 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

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

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

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

222. END ACID - BASE BALANCE