Acid, Base, Electrolytes

1. Acid, Base, Electrolytes Balance and Alterations

2. Fluid Compartments

3. Fluid Compartments:20 – 40 – 60 Rule

4. Fluid Movement

5. Input = output Hormones Na+ / K+ Renin Aldosterone ANP Reproductive Hormones GCC Ca++ / Mg++ Calcitonin PTH H2O ADH Anions follows passively Cl- HCO3- PO4= Water and Electrolyte Balance

6. Water • Intake • Loss • Normal • Abnormal • Osmosis • Hormonal control • Capillary Dynamics • CHP • COP • IHP • IOP

7. Osmosis

8. Capillary Dynamics

9. Capillary Pressures

10. Fluid Shift to third space • Edema • Effusion • Transudate • Low cell • Low protein • Exudate • Types: Nonseptic, Septic • Contents • High cell • High protein

11. Edema • Causes • Obstruction • Overload • Inflammation • hypoalbuminemia • Vessels • Angioedema • Lymphedema • Types • Localized • Pitting • Weeping • Dependent • Generalized

12. Pulmonary Edema

13. Pleural Effusion

14. Terminology • Isotonic • Hypovolemia • Hypervolemia • Hypertonic • Hyperosmolar • Hypotonic • Hypo-osmolar

15. Functions of electrolytes

16. Electrolyte Fluid Composition

18. Hormones that regulate Electrolytes • Aldosterone • ANP • PTH • Cacitriol • Calcitonin

19. Cations • + charge • Location • Function • Hormonal Controls • Alterations • Hypo- • Hyper-

20. < 135 mEq/L Etiology Decreased Na+ (diet) Increased H20 Diuretics Hiridosis Addison’s Disease DM Diarrhea CRF Clinical Signs H20 shift to ICF Cells swell CNS sensitive V/D Lethargy Confusion Seizures Muscle weakness Hyponatremia

21. Hyponatremia

22. > 147 mEq/l Etiology Excessive intake Hyperaldosteronism Drowning (salt water) H20 loss DI Renal Fever / Sweat Burns Diarrhea Clinical Signs Osmotic shrinkage CNS sensitive Lethargy Irritability Hemorrhage Seizures Coma Muscle weakness Hypernatremia

23. < 3.5 mEq/l Etiology Decreased intake ANS V/D Diuretic Sweating Digitalis Insulin excess Clinical Signs Decreased RMP Heart dysrhythmia Bradycardia AV blocks PVCs Sphincter weakness Delayed cardiac repolarization ST segment depression T decreased/inverted Hypokalemia

24. > 5.5 mEq/l Etiology Increased intake Insulin deficiency Hemolysis Hypoxia CRF Diuretics Burns Extensive surgeries Clinical Signs Inactivate Na+ channels Muscle weakness Muscle paralysis paralysis Cardiac dysrhythmia Peaked T wave Widened QRS Hyperkalemia

25. < 8.5 mg/dL Etiology Nutritional deficiency Osteoblastic metastasis PTH deficiency Hyperphosphatemia Increased protein binding Chelation therapy Clinical Signs NMJ irritability Muscle Spasm Dyspnea Seizures Colic Tetany Cardiac Dysrhythmia Hypocalcemia

26. > 10.5 mg/dL Etiology Cancer Hyperparathyroidism Bone remodeling Increased reanal filtering Clinical Signs NMJ decreased Fatigue Lethargy Weakness Cardiac dysrhythmia Bone loss Urolithiasis Hypercalcemia

27. < 1.5 mEq/l Seen with hypokalemia and hypocalcemia Etiology Decreased dietary intake GI loss Malabsorption Maldigestion Diarrhea CRF Clinical Signs Decreased threshold Tetany Vertigo Nystagmus Muscle spasms hyperreflexia Seizures Cardiac Dysrhythmia Hypomagnesemia

28. > 2.5 mEq/l Etiology Excess intake (antacids) Decreased renal excretion CRF Adrenal insufficiency Clinical Signs Increased threshold for depolarization Muscle weakness Decreased reflexes Hypotension Decrease Na+ current Cardiac dysrhythmia Bradycardia Hypermagnesemia

29. Chloride ECF Alterations Hypochloremia < 95 mEq/L Accompanies hyponatremia Severe vomiting Diuretics Hyperchloremia > 103 mEq/L Accompanies hypernatremia Phosphate ICF, stored in bones Alterations Hypophosphatemia < 2.7 mg/dL Antacid use Prolonged decrease cam cause Rickets/’Osteomalacia Hyperphosphatemia > 4.5 mg/dL Renal failure Overuse of laxatives Hypoxia Anions

30. Acid Base Terms • Define • pH • Acid • Strong • Weak • Volatile : CO2 from CH20 and Fat Metabolism • Nonvolatile: H2SO4, H2PO4 from protein metabolism • Base • Strong • Weak • Salt • Buffer

31. Acid Sources

33. pH • Define • pH = log (1/[H+]) • pH = -log [H3O+] • Water Dissociation • H2O + H2O  H3O+ + OH- • Scale • Blood values • Venous • Arterial • Abnormal Values • Acidemia • Alkalemia

34. pH formula and scale

35. Acid Base Chart

36. pH of Solutions

37. Acid Base Regulation for Balance • Systems • Chemical Buffer Systems • Respiratory System • Renal • Time • Seconds to Minutes • Minutes to Hours • Hours to Days / Weeks • Strength • Problems (reference 7.4 as normal average): • + / - 0.1 changes result in respiratory rate changes • + / - 0.2 to 0.3 changes result in CV and Nervous changes • + / - 0.4 to 0.5 changes result in death

38. Chemical Buffer Systems • Define • 3 types • Name of System • Buffer formula or name of chemical • Location • Effectiveness [pKa buffer = pH location] • Why important

39. pH changes with/without buffers

40. Bicarbonate Chemical Buffer • H2CO3, HCO3- • Plasma buffer • pK = 6.1 • Important: • Can measure components • pCO2 = 40 mmHg • HCO3- = 24 mM • Can adjust concentration / ratio of components • HCO3- @ kidneys • CO2 @ lungs • Recalculate pH of buffer system in ECF using Henderson-Hasselbach • pH = 6.1 + log(24 / 0.03x40) • pH = 6.1 + log (20/1) • pH = 7.4

41. Bicarbonate Buffer System

42. Phosphate Chemical Buffer • H2PO4-, HPO4= • ICF, Urine • pK = 6.8 • Important • Intracellular buffer • ICF pH = ~ 6.5 – 6.8 • Renal Tubular Fluids • Urine pH ranges 6.0 – 7.0

43. Protein Chemical Buffer • Proteins • With Histadine: AA contain imidazole ring, pKa = 7.0 • R-COOH  R-COO- + H+ • R-NH2  R-NH3+ • ICF (hemoglobin), ECF • pK = 7.4 • Important • Most numerous chemicals • Most powerful chemical buffer

44. Proteins in acid base

45. Hemoglobin

46. CO2 transport and RBC buffer

47. Respiratory for A/B Balance • Occurs in minutes • CO2 only • Rate changes

48. Respiratory Controls for Acid /Base balance • Volatile Acid: CO2 • pH changes in CSF • Respiratory Rate • Pons • Medulla Oblongata • Chemoreceptors • pCO2 • pO2

49. CO2 and pH • Increase CO2 • Increase H+ • Decrease pH • Decrease CO2 • Decrease H+ • Increase pH

50. Renal Control for Long Term Acid / Base Balance