electrolyte balance with investigations.

water and electrolyte balance with the different organs involved in the management of electrolyte Absorbtion and release

1. WATER AND ELECTROLYTE BALANCE POST GRADUATE DEPT OF BIOCHEMISTRY SBMCH

2. FUNCTIONS OF WATER 1.PROVIDES AQUEOUS MEDIUM FOR ALL THE BIOCHEMICAL REACTIONS IN THE BODY 2.REACTANT IN METABOLIC REACTIONS 3.VEHICLE FOR TRANSPORT OF SOLUTES 4.CLOSELY ASSOCIATED WITH REGULATION OF BODY TEMPERATURE

3. WATER DISTRIBUTION IN THE BODY 60% OF THE BODY WEIGHT IS WATER 1.INTRACELLULAR FLUID 2.EXTRACELLULAR FLUID 28L ----INTRACELLULAR FLUID 42L < 14L----EXTRACELLULAR FLUID INTRAVASCULAR FLUID 2.8 L EXTRAVASCULARFLUID 11.2 L

4. ADULT HUMAN : 60% WATER 14 L ( ECF) INTERSTITIAL FLUID 10.5 L PLASMA 3.5 L

5. WATER INTAKE EXOGENOUS 1) INGESTED WATER AND BEVERAGES 2) SOLID FOODS ENDOGENOUS METABOLIC WATER FROM OXIDATION OF FOODSTUFFS 1g OF CARBOHYDRATE .PROTEIN AND FAT YIELD 0.6ml,0.4ml,1.1ml WATER RESPECTIVELY

6. WATER OUTPUT WATER LOSS OCCURS FROM URINE,SKIN,LUNGS AND FAECES URINE : 1-2 L/DAY WATER REGULATION IS CONTROLLED BY HARMONE VASOPRESSIN

7. SKIN – 450ML/DAY WATER LOSS LUNGS – 400 ML/DAY LOSS OF WATER BY PERSPIRATION AND RESPIRATION IS CALLED INSENSIBLE WATER LOSS FAECES: 150 ML/DAY

8. WATER BALANCE IN THE BODY INTAKE PER DAY OUTPUT PER DAY Water in food 1250ml Urine 1500ml Oxidation of food 300ml S kin 500ml Drinking water 1200ml Lungs 700ml Feces 50ml 2750ml 2750ml

9. REGULATION OF WATER BALANCE ADH- SECRETED FROM POST. PITUITARY GLAND ADH PROMOTES WATER REABSORPTION FROM KIDNEYS AND THUS REDUCES THE LOSS OF WATER FROM BODY 2) ALDOSTERONE Hormone produced in adrenal cortex.It increases Na+ reabsoption by renal tubules. 3)THIRST CENTRE located in hypothalamus of brain and regulates the intake of water . Dehydration stimulates the thirst centre which causes us to drink water 4) URINE FORMATION if excess water is injected the kidney responds to it `and excess water is excreted in urine and water balance is maintained

10. ELECTROLYTES THE MAJOR ELECTROLYTES IN THE PLASMA ARE CATIONS (POSITIVELY CHARGED IONS) sodium Na+,pottasium K+,calcium Ca+ magnesium Mg + B) ANIONS (NEGATIVELY CHARGED IONS) chloride( cl -),Bicarbonate(HCo3-),sulfate(so4-

11. EL E C T R O L YTE B ALANCE Electrolytes are the compounds which readily dissociate in solution and exist as ions ie., positively and negatively charged particles. The electrolytes is expressed as milliequivalents(mEq/L) rather than milligrams.

12. ELECTROLYTE S COMPOSITION OF BODY FLUIDS _ _ EXTRACELLULAR FLUID (PLASMA) INTRACELLULAR FLUID (MUSCLE) CATIONS _ ANIONS CATIONS ANIONS Na+ 142 Cl 103 K 150 HPO 2- 3 140 K+ 5 HCO 3 27 Na 10 HCO 3 10 Ca2+ 5 HPO 2- 3 2 Mg 40 _ Cl 2 Mg2+ 3 SO 2- 4 1 Ca 2 SO 2- 4 5 PROTEINS 16 PROTEINS 40 O R GANIC ACIDS 6 O R GANIC ACIDS 5 155 155 202 202

13. REGULATION OF SODIUM AND WATER BALANCE -MAJOR REGULATORY FACTORS Hormones ( Aldosterone , ADH) Renin-Angiotensin system. ALDOSTERONE ( mineralocorticoid Zona Glomerulosa of adrenal cortex ) ( REGULATES) Na+ – K+ exchange and Na+ – H + exchange at the Renal Tubules. Net effect is SODIUM RETENTION.

14. Anti – Diuretic Hormone (ADH) When Plasma Osmolality increases(due to Na) Osmorecepters of Hypothalamus are stimulated ADH secretion Resulting in Increases water reabsorption b y the renal tubles

15. Renin-Angiotensin System When ECF volume falls Renal plasma flow decreases Leads to Release of RENIN by juxtaglomerular cells

16. FACTORS WHICH STIMULATE THE RENIN RELEASE • Decreased BP • Salt depletion • Prostaglandins INHIBITS THE RENIN RELEASE • Increased BP • Salt intake • Prostaglandin inhibitors • Angiotensin - II

17. ATRIAL NATRIURETERIC FACTOR(ANF) polypeptide hormone secreted by right atrium of the heart ANF increases the urinary sodium excretion

18. CLINICAL CONDITIONS 1. DEHYDRATION

19. SIGNS OF SEVER E DEHYDRATION

20. SHOCK

21. TREATMENT Intake of plenty of water Or IV isotonic solution(usually 5% Glucose) Electrolytes either oral or IV Monitoring the water and electrolyte status of body.

22. OVERHYDRATION Overhydration can lead to water intoxication. This occurs when the amount of salt and other electrolytes in your body become too diluted. Hyponatremia is a condition in which sodium (salt) levels become dangerously low. This is the main concern of overhydration.

23. CAUSES OF overhydration By making your body hold on to more fluid. These includes: congestive heart failure (CHF) liver disease kidney problems Syndrome of inappropriate antidiuretic hormone nonsteroidal anti-inflammatory drugs uncontrolled diabetes

24. SYMPTOMS OF overhydration common symptoms includes: nausea and vomiting Headache changes in mental state such as confusion or disorientation Untreated overhydration can lead to dangerously low levels of sodium in your blood. This can cause more severe symptoms, such as: muscle weakness , spasms , or cramps S eizures U nconsciousness coma

25. How is overhydration treated? Cutting back on your fluid intake Taking diuretics to increase the amount of urine you produce Treating the condition that caused the overhydration Stopping any medications causing the problem Replacing sodium in severe cases

26. SODIUM Major cation of Extracellular fluid Total body sodium is 4000mEq, 50% - Bones , 40% - ECF , 10% - soft tissues Normal Sr. Plasma level 136 – 145mEq/L

27. Hyponatremia Hyponatremia is a low sodium level in the blood . It is generally defined as a sodium concentration of less than 135 mEql/L Severe hyponatremia being below 120 mEql/L Symptoms : Mild symptoms  decreased ability to think, headaches , nausea, Severe symptoms  confusion, seizures , and coma .

28. CAUSES SEVERE VOMITING DIARRHEA BURNS SWEATING ADDISON’S DISEASE( Adrenocortical insufficiency) RENAL TUBULAR ACIDOSIDS

29. Hypernatremia Hypernatremia  is a high sodium ion level in the blood . Serum sodium level of more than 145 mmol/L. Severe symptoms occurs when levels are above 160 mmol/L SYMPTOMS : Early symptoms  a strong feeling of thirst , weakness, nausea, and loss of appetite. Severe symptoms  confusion , muscle twitching, and bleeding in or around the brain .

30. HYPERNATREMIA CAUSES CUSHING’S SYNDROME( Adreno cortical hyperactivity) PROLONGED CORTISONE THERAPY DECREASED INTAKE OF WATER PREGNANCY(where steroid hormones cause sodium retention) DEHYDRATION EXCESS INTAKE OF SALT

31. OTHER CAUSES

32. POTASSIUM Total body content of potasium  3500mEq Major cation of INTRACELLULAR FLUID. Maintains intracellular Osmotic Pressure. Normal serum potassium level  3.5-5.2mmol/L The cells contains 160mEq/L, so precaution should be taken to prevent hemolysis when estimating for concentration of potassium

33. Hypokalemia Hypokalemia is a low level of potassium (K + ) in the blood serum . Levels below 3.5 mmol/L defined as hypokalemia. Symptoms : Mildly low levels do not typically cause symptoms. Feeling tired , leg cramps, weakness & constipation It increases the risk of an abnormal heart rhythm , which are often too slow , and can cause cardiac arrest .

34. Causes of hypokalemia include Diarrhea , medications like furosemide and steroids , Dialysis , D iabetes Insipidus Hyperaldosteronism , H ypomagnesemia , not enough intake in the diet. It is classified as severe when levels are less than 2.5 mmol/L. Low levels can also be detected on an electrocardiogram (ECG)  T wave is inverted

35. H YPERKALEMIA Hyperkalemia is an elevated level of potassium (K + ) with levels above 5.5 mmol/L in the blood serum SYMPTOMS : Typically this results in no symptoms. when severe  palpitations , muscle pain , muscle weakness , or numbness . An abnormal heart rate can occur which can result in cardiac arrest and death.

36. Common causes includes :- kidney failure , hypoaldosteronism , and rhabdomyolysis . Medications which cause high blood potassium includes spironolactone , NSAIDs , and angiotensin converting enzyme inhibitors . The severity is divided into  Mild (5.5-5.9 mmol/L ),  Moderate (6.0-6.4 mmol/L),  severe (>6.5 mmol/L). High levels can also be detected on an electrocardiogram (ECG)  ELEVATED ‘T’ WAVE Pseudohyperkalemia, due to breakdown of cells during or after taking the blood sample, should be ruled out.

37. CHLORIDE Intake , output and metabolism of sodium and chloride run in parallel. The normal serum range for chloride is 97 to 107 mEq/L. In CSF  125 mEq/L Renal threshold for Chloride is about 110mEq/L. Daily excretion of chloride is 5-8mg/L

38. HYPER CHL O R E MIA Hyperchloremi a is an electrolyte disturbance in which there is an elevated level of the chloride ions in the blood . The normal serum range for chloride is 96 to 106 mEq/L , chloride levels at or above 110 mEq/L usually indicate kidney dysfunction as it is a regulator of chloride concentration .

39. Symptoms and causes includes : Dehydration  due to diarrhea, vomiting, sweating Hypertension  due to increased sodium chloride intake Cardiovascular dysfunction  due to increased sodium chloride intake Edema  due to influx in sodium in the body Weakness  due to loss of fluids Thirst  due to loss of fluids

40. Kussmaul breathing  due to high ion concentrations, loss of fluids, or renal failure High blood sugar  due to diabetes Hyperchloremic metabolic acidosis  due to severe diarrhea and/or renal failure Respiratory alkadosis  due to renal dysfunction

41. Hypochloremia Hypochloremia is an electrolyte disturbance in which there is an abnormally low level of the chloride ion in the blood . It is associated with hypoventilation , chronic respiratory acidosis . respiratory acidosis + metabolic alkalosis (decreased blood acidity) it is often due to vomiting . It occurs in cystic fibrosis.