Fluid and electrolytes

intravenous fluid and electrolytes are important topics in medical science. potassium is one of the vital electrolytes of the human body. this presentation has a discussion on several iv fluids and potassium balance and also how to manage the potassium imbalance.

1. Presenter: Dr Maimuna Sayeed Resident- Phase B Paediatric Gastroenterology and Nutrition BSMMU, Dhaka Fluid and Electrolytes

2. Introduction Fluid and electrolyte balance is a dynamic process that is crucial for life It plays an important role in homeostats Imbalance may result from many factors, and it is associated with the illness

3. Body fluids/Water Provide transportation of nutrients to cells Carry waste products away from cells Provide the environment for electrolyte chemicals reactions to occur Aids in regulation of body temperature Maintain blood volume Solvent for minerals, vitamins and glucose

4. Fluid compartment of the body Total body fluid 60% of total body weight Extracellular fluid Total 20% of body weight Intracellular fluid Total 40% of total body weight Interstitial fluid 15% of total body weight Plasma 5% of total body weight Transcellular fluid Fluid in potential spaces Fluid in GIT and respiratory tract Intraocular fluid CSF Pleural cavity Pericardial cavity Peritoneal cavity

5. F luid therapy Intravenous fluid therapy: Crystalloid Colloid

6. Definitions Solute: a particle, usually a salt Solvent: liquid, usually water Solution: solute and solvent mixed together

7. Osmolarity : the concentration of a solution expressed as the total number of solute particles per litre . Osmolality : the concentration of a solution expressed as the total number of solute particles per kilogram Tonicity: is a measure of the effective osmotic pressure gradient , as defined by the water potential of two solutions separated by a semipermeable membrane

8. what solutions’ tonicity can be: Hypotonic: low solute, high solvent Isotonic: equal solute and solvent ratio Hypertonic: high solute, low solvent

9. Osmolality: 275-295mmol/kg Lower osmolality is <275mmol/kg and means blood is hypotonic Higher osmolality is >295mmol/kg and means blood is hypertonic

10. Isotonic Iso: same/equal Tonic: concentration of a solution The cell has the same concentration on the inside and outside which in normal conditions the cell’s intracellular and extracellular are both isotonic. Isotonic solutions are used: to increase the EXTRACELLULAR fluid volume due to blood loss surgery dehydration

11. Isotonic fluids 0.9% NaCl (Normal Saline) 5% dextrose in water (D5W ) (In the bag ) also used as a hypotonic solution after it is administered because the body absorbs the dextrose BUT it is considered isotonic 5% Dextrose in 0.225% saline (D5W1/4NS) Lactated Ringer’s

12. Hypotonic Hypo: ”under/beneath” Tonic: concentration of a solution The cell has a low amount of solute extracellularly and it wants to shift inside the cell to get everything back to normal via osmosis. This will cause CELL SWELLING which can cause the cell to burst or lyses . Hypotonic solutions are used when the cell is dehydrated and fluids need to be put back intracellularly. diabetic ketoacidosis (DKA) hyperosmolar hyperglycemia

13. Hypotonic solutions D5W (in the body) 0.25% NaCl 0.45% NaCl (half normal saline) 2.5% Dextrose

14. Hypertonic Hyper: excessive Tonic: concentration of a solution The cell has an excessive amount of solute extracellularly and osmosis is causing water to rush out of the cell intracellularly to the extracellular area which will cause the CELL TO SHRINK . When hypertonic solutions are used (very cautiously; most likely to be given in the ICU due to quickly arising side effects of pulmonary edema/fluid over load). In addition, it is preferred to give hypertonic solutions via a central line due to the hypertonic solution being vesicant on the veins and the risk of infiltration .

15. Hypertonic solutions 3% Saline 5% Saline 10% Dextrose in Water (D10W) 5% Dextrose in 0.9% Saline 5% Dextrose in 0.45% saline 5% Dextrose in Lactated Ringer’s

16. Electrolyte composition & osmolarity of common IV fluid Intravenous fluid (crystalloids) Osmolarity ( mOsm /L) Na+ ( mmol /L) Cl- ( mmol /L) Components Normal saline (0.9% NaCl ) 306 154 154 NaCl 5% dextrose in aqua 278 - - Glucose 5% dextrose in NS 560 154 154 Glucose., NaCl 0.45% NaCl 153 77 77 NaCl %5 dextrose in 0.45% NaCl 406 77 77 Glucose, NaCl 5% dextrose in 0.25% NaCl 320 34 34 Glucose, NaCl 3% NaCl 1026 513 513 NaCl Ringer’s lactate 273 130 130 NaCl , K+, Ca++, lactate

17. Hypertonic, Hypotonic, & Isotonic Fluid Solution Quiz

18. A patient is being admitted with dehydration due to nausea and vomiting. Which fluid would you expect the patient to be started on ? A. 5% Dextrose in 0.9% Saline B. 0.33% saline C. 0.225% saline D. 0.9% Normal Saline The answer is D: 0.9% Normal Saline

19. _______ solutions cause cell dehydration and help increase fluid in the extracellular space. A. Hypotonic B. Osmosis C. Isotonic D. Hypertonic The answer is D: Hypertonic

20. Which of the following is not a hypertonic fluid? A. 3% Saline B. D5W C. 10% Dextrose in Water (D10W) D. 5% Dextrose in Lactated Ringer’s The answer is B: D5W

21. The doctor orders an isotonic fluid for a patient. Which of the following is not an isotonic fluid ? A. 0.9% Normal Saline B. Lactated Ringer’s C. 0.45% Saline D. 5% Dextrose in 0.225% saline The answer is C: 0.45% Saline

22. Common intravenous colloid solution Albumin solution 5% albumin in normal saline, 25% albumin in normal saline Dextran solution Hetastarch solution

23. Clinical use of colloid solution Act as plasma expander in hypovolemic state Infusion of colloid solution increases the colloidal osmotic pressure of plasma, because infused colloids remain restricted in intravascular space since they are impermeable to capillary epithelium. As a result fluid from extravascular space moves into intravascular space to increase plasma volume which helps to maintain normal cardiovascular health in hypovolemia and during major surgery causing hemorrhage

24. Electrolytes Electrolytes account for approximately 95 % solute molecules in body water. Sodium Na+ predominant extracellular cation . Potassium K+ is the predominant intracellular cation .

25. Potassium Potassium is the second most abundant cation in the body About 98% of potassium is intracellular and that is particularly in the skeletal muscle. Because most potassium is intracellular, the plasma concentration does not always reflect the total body potassium content. Hypokalemia andHyperkalemia in Infants andChildren: Pathophysiologyand Treatment,Kayleen Daly,

26. Nelson TEXTBOOK of PEDIATRICS EDITION 20

27. Distribution Most abundant cation of ICF , help to maintain ICF volume. 2% in the ECF 98% in the ICF

28. 3Na + 2K + ATPase K + cell = 140-160 mEq/L K + e = 4-5 mEq/L Trans-cellular K+ Distribution

29. The Na+K +-ATPase maintains the high intracellular potassium concentration by pumping sodium out of the cell and potassium into the cell. Nelson TEXTBOOK of PEDIATRICS EDITION 20

30. Importance Potassium is necessary for the electrical responsiveness of nerve and muscle cells and for the contractility of cardiac, skeletal, and smooth muscle. The intracellular potassium concentration affects cellular enzymes. Potassium is necessary for maintaining cell volume because of its important contribution to intracellular osmolality. Nelson TEXTBOOK of PEDIATRICS EDITION 20

31. Normal serum potassium levels in children Age Range (mEq/L or mmol/L) Premature infant 4 to 6.5 Newborn 3.7 to 5.9 Infant 4.1 to 5.3 Child > 1 year old 3.5 to 5 UpToDate

32. Intake Potassium is plentiful in food . Dietary consumption varies considerably, even though 1-2 mEq /kg is the recommended intake. Nelson TEXTBOOK of PEDIATRICS EDITION 20

33. Foods high in potassium Fruits Bananas, oranges (citrus), cantaloupe, watermelon, apricots , raisins, prunes, pineapples, cherries, and tomatoes Vegetables Green and leafy, potatoes, avocados, artichokes, lentils, beets , white mushrooms, and onions Meats/Fish All contain potassium (the lowest levels are in chicken liver, shrimp , and crab) Potassium content of selected foods percommon measure, sorted by nutrient contentNational Nutrient Database for Standard Reference,Released 2012)

34. Breads/Flours Pumpernickel, buckwheat, and soy Miscellaneous Chocolate, cocoa, brown sugar, molasses, nuts, peanu tbutter , French fries, and whole milk

35. Potassium content in popular foods and beverages Food/beverage Pota8.6ssium content ( mEq ) French fries 17.7 Small banana 8.6 White mushrooms 8.1 Orange juice (200 ml) 7.9 Whole milk (200 ml) 7.7 Broccoli 5.8 Potato chips 5.1 Green beans 3.9 Milk chocolate bar (20 g) 2.4 Onions, cooked 1.5 Coca-Cola (200 ml) 0.1 Potassium content of selected foods percommon measure, sorted by nutrient contentNational Nutrient Database for Standard Reference,Released 2012)

36. Absorption The intestines normally absorb approximately 90% of ingested potassium. Most absorption occurs in the small intestine , whereas the colon exchanges body potassium for luminal sodium. Nelson TEXTBOOK of PEDIATRICS EDITION 20

37. Excretion There is some loss of potassium in sweat , but it is normally minimal. The colon has the ability to eliminate some potassium in the stool but most ingested potassium is eventually excreted in the urine . Nelson TEXTBOOK of PEDIATRICS EDITION 20

38. Components of Potassium Homeostasis Intake ECF ICF Distribution Excretion 90% Kidney 10% Colon Insulin Aldosterone

39. Regulation of potassium balance (homeostasis ) Short term regulation (internal K+ balance) –done by transmembrane potassium flux Long term regulation (external K+ balance) –done by kidney

40. Factors regulating transmembrane potassium flux Factor Function Effect on serum K+ Insulin Influx Hypokalemia Aldosterone Alkalosis Acute potassium excess B agonist (epinephrine) A blocker Glucagon Efflux Hyperkalemia ECF hyperosmolarity Acute potassium deficit Acidosis A agonist (norepinephrine) B blocker abc of medical biochemistry, Prof. md. Mozammel Hoque

41. Increase K+ intake Increase plasma K+ Adrenal cortex Increase aldosterone Kidney Increase K+ excretion Negative feedback

42. Hormone regulating potassium secretion Aldosterone , Glucocorticoids , ADH Insulin C atecholamines Nelson TEXTBOOK of PEDIATRICS EDITION 20

43. Potassium imbalance Deficit : hypokalemia Excess: hyperkalemia

44. HYPERKALEMIA Hyperkalemia is defined as a serum or plasma potassium that is higher than the upper limit of normal potassium, which typically is considered to be 5.5 mEq /L ( mmol /L ) Causes, clinical manifestations, diagnosis, and evaluation of hyperkalemia in children, Author:Michael J Somers, MD

45. Causes of Hyperkalemia Three basic mechanisms cause hyperkalemia Increased intake Transcellular shifts Decreased excretion Spurious laboratory value Nelson TEXTBOOK of PEDIATRICS EDITION 20

46. Causes of Hyperkalemia SPURIOUS LABORATORY VALUE Hemolysis Tissue ischemia during blood drawing Thrombocytosis Leukocytosis Familial pseudohyperkalemia INCREASED INTAKE Intravenous or oral TRANSCELLULAR SHIFTS Acidosis Rhabdomyolysis Tumor lysis syndrome Tissue necrosis Hemolysis/hematomas/gastrointestinal bleeding Succinylcholine

47. TRANSCELLULAR SHIFTS Digitalis intoxication Fluoride intoxication β- Adrenergic blockers Exercise Hyperosmolality Insulin deficiency Malignant hyperthermia Hyperkalemic periodic paralysis DECREASED EXCRETION Renal failure DECREASED EXCRETION Primary adrenal disease: Acquired Addison disease 21-Hydroxylase deficiency 3β- Hydroxysteroid dehydrogenase deficiency Lipoid congenital adrenal hyperplasia Adrenal hypoplasia congenita Aldosterone synthase deficiency

48. Hyporeninemic hypoaldosteronism: Urinary tract obstruction Sickle cell disease Kidney transplant DECREASED EXCRETION Renal tubular disease: Pseudohypoaldosteronism type I Pseudohypoaldosteronism type II Bartter syndrome, type 2 Urinary tract obstruction Kidney transplant Medications: Angiotensin-converting enzyme inhibitors Angiotensin II blockers Potassium-sparing diuretics Calcineurin inhibitors Nonsteroidal antiinflammatory drugs Trimethoprim Heparin Drospirenone (in some oral contraceptives)

49. Clinical Manifestations The cardiac conduction system is usually the dominant concern. V entricular fibrillation Asystole P aresthesias , F asciculations , W eakness A scending paralysis Nelson TEXTBOOK of PEDIATRICS EDITION 20

50. DIAGNOSIS History initially focus on potassium intake , risk factors for transcellular shifts of potassium, medications that cause hyperkalemia , and the presence of signs of renal insufficiency , such as oliguria and edema. Symptoms : weakness, paralysis Physical findings : none specific

51. Initial laboratory evaluation should include S. Electrolytes: serum K+ > 5.5 S. creatinine BUN , and A cid–base status . Electrocardiogram (ECG)

52. Electrocardiographic manifestations for hyperkalemia Serum potassium concentration Electrocardiographic manifestations 5.5-6.5 mEq /L Tall, peaked, ‘‘tented’’ T waves, normal or decreased QT, PR interval shortening 6.5-7.5 mEq /L Widening of QRS complex, increased PR interval 7.0-8.0 mEq /L Broad, low-amplitude P waves, QT prolongation, ST elevation or depression > 8 mEq /L P waves disappear, marked widening of QRS + ‘‘sine wave’’ pattern, high risk for ventricular fibrillation or asystole Taketomo , Hodding , & Kraus (2013)and Sood , Sood , & Richardson. (2007). Emergency management and commonly en -countered outpatient scenarios in patients with hyperkalemia.

53. Severity of hyperkalemia Mold : serum K+ 5.5-6.5 mmol /L Moderate : serum K+ 6.5-8 mmol /L Severe : serum K+ >8 mmol /L

54. Treatment Treatment of hyperkalemia depends on the serum potassium level , as well as the presence or absence of symptoms and ECG changes . Treatment is recommended when ECG changes are present or when serum potassium levels are greater than 6 to 6.5 mEq /L, regardless of the ECG findings.

55. The treatment of hyperkalemia has 2 basic goals : ( a) to stabilize the heart to prevent life-threatening arrhythmias and ( b) to remove potassium from the body Nelson TEXTBOOK of PEDIATRICS EDITION 20

56. How to manage? Check sampling error and recheck value by sending free flow of blood Identify and remove all sources of oral or parenteral potassium intake (oral potassium supplements and intravenous maintenance fluids or parenteral nutrition must be considered) and evaluate drugs that can increase the serum potassium level (e.g., potassium-sparing diuretics, angiotensin-converting enzyme inhibitors, and nonsteroidal antiinflammatory agents)

57. A. Mild hyperkalemia (<6mmol/L ) Restrict/avoid intake of extra potassium through potassium containing food or fluid

58. B. Moderate to severe hyperkalemia (>6mmol/L ) Myocardial cell membrane stabilization Calcium gluconate (10%) dose: 0.5-1ml/kg IV slowly over 5-10 min Redistribution of extracellular K+ into cells Insulin (short acting) dose: 0.1 unit/kg, IV with 10% DA @ 5ml/kg over 30 min Salbutamol nebulization dose: 2.5mcg (<25kg) or 5 mcg (>25kg) with normal saline (2ml) Sodium bi carbonate dose:1-2ml/kg, IV slowly over 10-15 min

59. Enhance elimination of K+ from the body through gut Sodium polystyrene sulfonate resin ( kayexalate ) Oral: 1mo-18 years Dose: 125-250mg/kg (max 15gm) in 15-30ml 70% sorbitol, 3-4/day Rectal: neonate – 18 years Dose: 125-250mg/kg , dilute each gm resin in 5-10ml methylcellulose or water, repeated as necessary, every 6-8hours Other ways to eliminate K+ from body (in refractory cases) Renal replacement therapy Peritoneal dialysis haemodialysis

60. HYPOKALEMIA Hypokalemia is defined as serum level below the normal value, which is usually defined as 3.5 mEq /L. It is common in children, with most cases related to gastroenteritis. UpToDate , Hypokalemia in children Authors: Michael J Somers, MD

61. Severity of hypokalemia Mild: 2.5 - 3.5 mmol /L Moderate: 2-2.5 mmol /L Severe: <2 mmol /L Nelson

62. Gastrointestinal Increased losses (diarrhea, vomiting, nasogastric drainage) Decreased intake (anorexia, bulimia) Increased potassium intracellular uptake Alkalosis Increased insulin activity Beta-adrenergic agents ( eg albuterol, epinephrine, dopamine) Periodic paralysis Genetic etiology Hyperthyroidism Other drugs Barium Antipsychotics Chloroquine Pediatric causes of hypokalemia

63. Increased urinary losses Increased distal delivery of sodium to distal nephron Diuretics Osmotic diuretics (mannitol, hyperglycemia) Non-re-absorbable anions (elevated serum bicarbonate level) Tubular injury (Cisplatin) Types I and II renal tubular acidosis Increased mitochondrial activity Hyperaldosteronism due to hypovolemia Glucocorticoid remediable aldosteronism (GRA) Apparent mineralocorticoi d excess (AME) Rare forms of congenital adrenal hyperplasia (17-alpha-hydroleses deficiency and 11-beta-hydroxylase deficiency ) Tubulopathies (Bartter syndrome, Gitelman syndrome) Amphotericin Enhanced sodium reabsorption (Liddle syndrome) Increased skin loss Cystic fibrosis

64. Clinical manifestation Clinical manifestation vary depending on the severity of hypokalemia. Symptom does not become manifest until the serum potassium level is below 3 mEq /L unless there is a rapid significant fall in serum potassium

65. Clinical features of hypokalaemia depend on potassium level: 3.0 – 3.5mmol/L – Usually asymptomatic. Malaise, weakness, constipation, muscle cramps, fatigue can occur. 2.5 – <3.0mmol/L - As above but more pronounced. Muscle necrosis, arrhythmias in patients with underlying cardiac problems. <2.0mmol/L – It can cause life threatening cardiac arrhythmias and respiratory muscles. It can also precipitate rhabdomyolysis, myoglobinuria , acute renal failure and paralysis of legs.

66. B . Clinical features of hypokalaemia depend on duration & rapidity of onset: Acute: Skeletal & smooth muscle weakness – respiratory difficulty, paralytic ileus Cardiac arrhythmia: Sinus bradycardia, Ventricular tachycardia, AV block Rhabdomyolysis Chronic: Growth failure Tubulointerstitial & cystic changes Polyuria Metabolic alkalosis Impaired glucose tolerance

67. Diagnosis History Acute GI illness with diarrhea or vomiting is the most common cause of hypokalemia in otherwise healthy children Decrease dietary potassium intake , may be an exacerbating factor, particularly in children with acute G illness and potassium loss. The use of medications that may promote intracellular potassium uptake ( adrenergic agents or exogenous insulin) or increase potassium excretion ( eg diuretics) UpToDate

68. Physical examination Cardiac rate and rhythm by auscultation to screen for arrhythmia Muscle strength and tone Evaluation effective circulatory volume and status UpToDate

69. Laboratory investigation S. electrolytes Blood pH ECG

70. Electrocardiographic manifestations for hypokalemia Serum potassium concentration Electrocardiographic manifestations < 3.5 mEq /L; does not correlate with specific potassium levels Increased P wave amplitude Prolonged PR interval, ST segment depression QT prolongation, reduction in T wave amplitude T wave inversion, U waves Taketomo, Hodding, & Kraus (2013)and Sood, Sood, & Richardson. (2007). Emergency management and commonly en-countered outpatient scenarios in patients with hyperkalemia.

71. Principles of management Treatment of the cause Correction of deficit Ensure maintenance Correction of ongoing loss

72. Factors that influence the treatment of hypokalemia include potassium level, clinical symptoms, renal function, the presence of transcellular shifts of potassium , ongoing losses, and the patient’s ability to tolerate oral potassium Severe, symptomatic hypokalemia requires aggressive treatment. Nelson TEXTBOOK of PEDIATRICS EDITION 20

73. Oral correction : - Asymptomatic patient - Can take orally - Mild or Moderate Hypokalemia oral dose: 2-4 mEq /kg/day with a maximum of 120-240 mEq /day in divided doses Harrison Nelson

74. Indication of IV correction : - Symptomatic patient - Can not take orally - Severe Hypokalemia Harrison

75. Steps of Correction Step: 1 = Calculate the deficit Step: 2= Calculate the maintenance Step : 3= Choose the route of administration of drug Step : 4 = Choose the Drug Step : 5 = Choose the Fluid if needed. Step: 6 = Consider other morbidity.

76. Correction of hypokalemia K+ deficit = (required K+ - observed K+) x body weight in kg x 0.3 + M aintenance (1-3 mmol /kg/day)

77. Example: A 15 days old baby, weight 2 kg, has serum K+= 2mmol/L. How to correct ? K+ deficit =(3.5-2) x2x0.3 =0.9 Maintenance= 2x2kg=4mmol/day Total requirement=0.9+4=4.9mmol As 1ml=2mmol So around 2.5 ml inj. KCl can be given in 24 hours of IV fluid

78. Another way to remember Serum K + Level Inj. KCl to be added in 100ml IV fluid >3 meq /L 1.5 ml=3 meq 2.5-3 meq /L 2ml=4 meq 2-2.5 meq /L 2.5ml=5 meq <2 meq /L 3ml=6meq Acute Liver Failure : Management Update, MD. WAHIDUZZAMAN MAZUMDER1, FAHMIDA BEGUM2, ASM BAZLUL KARIM3 ,BANGLADESH J CHILD HEALTH 2017; VOL 41 (1): 53-59

79. About oral KCl Oral Syrup 5 ml = 6.7 mmol Trade name : KT, Electro K Adverse effect of Oral KCl : - GIT irritation - Esophageal and small intestinal erosion and stricture .

80. About IV KCl Inj 1 ml = 2 mmol , 1 amp = 10ml Potassium solution should not exceed 40mmol/L while giving through peripheral line The IV infusion rate should usually not exceed 1 mEq /kg/hr. It should not be mixed with dextrose solution

81. What I hear, I forget; What I see, I remember. What I do, I understand. - Confusius , 451 BC Thank you