المحاضرة الثانية طب الاطفال قسم التمريض.pptx

هذه المحاضرة تتحدث عن إعطاء السوائل للأطفال في حالة الجفاف أو أي مرض وهي مختصرة فمن أراد زيادة تفاصيل يقرأ كتاب من كتب الأطفال

1. 1 Fluid and electrolyte management in paEdiatrics Dr: Mohammed Al-Yahairy

2. OUTLINE: Introduction Fluid and electrolyte physiology Disturbances of fluid and Electrolytes Fluid therapy Electrolyte therapy

3. INTRODUCTION Fluid and electrolyte (F & E ) therapy is an essential component of care of sick children F & E requirements in health and sickness may change with growth in children. Many factors contribute to F & E disturbances of children Understanding the pathophysiology of the disease process is important in F & E therapy. F & E therapy is categorized into shock, deficit and maintenance therapy In children the turnover of Total body water(TBW) is 15-20% in 24 hrs compared to 5% in adults. As a result, fluid losses in infants and young children constitute significant percentage reduction of extra cellular fluid volume.

4. Body Composition Fluid 60% Solid 40 % Fat Protein Carbohydrate Minerals 4

5. Distribution of body fluids (by wEIGHt ) Fluid (60 % of Body weight) Intracellular Extracellular Interstitial Intra vascular(plasma) 5 Intracellular 40% (cytoplasm, nucleoplasm ) Interstitial 15% (lymph, CSF, synovial fluid, aqueous humor and vitreous body of eyes, between serous and visceral membranes, glomerular filtrate of kidneys. ) Plasma 5% There is continuous ongoing equilibrium between the intracellular and extracellular spaces.

6. Fluid content according to age Total body water (TBW) vary with age: Preterm = 80-85% Term = 75% Infant= 65% Older children & adult male= 60% Adult female=50% 6 TBW ↓ to 60% by 1st yr of life Female has less fluid content because of more fat cells Age Body water(%) ECF (%) ICF(%) Term baby 75 35-44 33 4-6 months 60 23 37 12 months 60 26-30 37 Puberty 60 20 40 Adult 50-60 20 40 Age and TBW

7. Composition of body fluid Water Electrolytes : Inorganic salts, Sodium(Na), Potassium(K), Calcium (Ca), Chloride(Cl), Phosphate(Po4), Bicarbonate(HCO3), Sulphate(SO4) Nonelectrolytes : Minerals -iron and zinc, Glucose, Lipids, Creatinine, Urea Electrolytes are measured in mEq or mmol Circulating electrolytes are electrically charged When positively charge called cation : Na + , K + , Ca ++ When negatively charge called anions : Cl - , HCO3 - , SO4 - 7

8. Electrolytes composition of body fluids Normal Values(serum) Cation : Sodium (Na +) 135 – 145 mEq /L Potassium (K + ) 3.5 – 5.5 mEq /L Calcium ( Ca ++ ) 8.5 – 10.5 mg/ dL Ionized Calcium 4.5 – 5.5 mg/ dL Magnesium (Mg++) 1.5 – 2.5 mEq /L Anion: Bicarbonate (HCO - 3 ) 24 – 30 mEq /L Chloride ( Cl -- ) 95 – 105 mEq /L Phosphate (PO 4 --- ) 2.8 – 4.5 mg/ dL 8

9. Concentration of Body fluid Units of solute concentration are osmolarity and osmolality Osmolarity : Number of osmoles of solute per liter (L) of solution. It is expressed as osmol /L e.g 1 mol/L NaCl solution has an osmolarity of 2 osmol /L Osmolality : Number of osmoles of solute per kilogram(kg) of solvent. It is expressed as osmol /kg Normal serum osmolality =280-298 mosmol /kg 9

10. Clinical relevance of osmolality Calculation: Serum osmolality ( mosmol /kg) = Effective osmolality: O smotic force that is mediating the shift of water between the ECF and the ICF = The osmotic gap ( osmolal gap): is the difference between the actual osmolality (measured by the laboratory) and the calculated osmolality A normal osmolal gap is < 10 mOsm /kg 10 2(Na + + K + ) mmol /l + Urea ( mmol /l)+ Glucose ( mmol /l) 2 x Na + ( mmol /l )+ Glucose ( mmol /l)

11. Regulation of Body Fluids Body fluid Homeostasis is maintained through Fluid intake Hormonal regulation Antidiuretic hormone(ADH) Renin- Angeotensin -Aldosterone Mechanism Natriuretic Peptides Fluid output 11

12. A. Fluid intake Intake is controlled by hypothalamic thirst center 12 ↑ plasma osmolality of 1–2% ↓ plasma volume 10%–15% Baroreceptor input, angiotensin II, and other stimuli Moistening of the mucosa of the mouth and throat Activation of stomach and intestinal stretch receptors −Ve

13. 1. Antidiuretic hormone(ADH) ADH: Secreted by the hypothalamus, and stored in the posterior pituitary gland ADH is released by, thirst, ↓ fluid volume, High serum osmolality Action reabsorb water from collecting duct of kidney inhibit sweat glands to ↓ perspiration to conserve water acts on arterioles , causes constriction thus ↑ Blood pressure. ADH is Inhibited by Excessive fluid volume Low osmolality of serum 13 B. Hormonal regulation

14. 2. Renin- Angiotensin-Aldosterone Mechanism 14 Low blood volume ↓Renal perfusion Renin from Kidney Angiotensinogen Angiotensin I Angiotensin II ACE Aldosterone from adrenal cortex Reabsorption of sodium and water Excretion of potassium

15. 3. Natriuretic Peptides Natriuretic Peptides Atrial Natriuretic Peptide(ANP ) from atria Brain Natriuretic Peptide(BNP) from ventricle Action Acts like a diuretic that causes sodium loss and inhibits the thirst mechanism Inhibit renin release Inhibit the secretion of ADH and aldosterone Vasodilatation 15

16. C. Regulation by fluid output 16 Daily fluid losses: Kidney(Urine): 55% Skin: 30% Lung: 10% GI (Stool): 2-5%

17. Fluid & Electrolyte therapy 17

18. Fluid therapy 18 Shock therapy : in severe dehydration Deficit therapy : Replacement of abnormal loss Maintenance therapy : Replacement of daily physiologic losses of water and electrolytes under normal condition

19. Shock therapy (over maximum 1 hour ) Ringer’s lactate or normal saline 20 ml/kg… I.V. infusion. (may be given over 10-15 minutes and may be repeated in severe cases) Hypovolemic shock is a common complication of severe dehydration. fresh blood or plasma transfusion : 10ml/kg I.V. …over 1 hour may be used in severe cases of hypovolemic shock but only after initial correction with RL or NS . 19 1- Shock therapy

20. 2- Deficit Therapy 20

21. 3- Maintenance Therapy  Goals of Maintenance Fluids: Prevent dehydration   Prevent electrolyte disorders    Prevent ketoacidosis    Prevent protein degradation

22. Calculation of daily maintenance fluid Daily Basis * Wt 1-10 kg: 100 ml/kg Wt 11 to 20 kg: 50 ml/kg Wt >20 kg up to 80 kg:20 ml/kg Maximum 2400 ml/day. 22 *Holliday-Segar Method

23. What types of IV fluid ? Normal saline (0.9% NaCl /L) = 154 mEq Na + / L One-half NS (0.45% NaCl /L) = 77 mEq Na + / L One-third NS (0.33% NaCl /L) = 57 mEq Na + / L One-quarter NS (0.25% NaCl /L) = 38 mEq Na + / L One fifth NS(0.18% Nacl ) = 30 mmol /l Ringer’s lactate= Na + 130 mmol / l,K + 4 mmol /l, Cl - ,109 mmol /l, bicarb 28 mmol /l , and Ca ++ 3 mg/dl )

24. Types of Oral Rehydration Solutions (ORS) - Salt sugar solution - Standard ORS - Low Osmolarity ORS Super ORS Super Super ORS - ReSoMal

25. Composition of ors solutions Composition Standard ORS ( mmol /l) Low osmolarity ORS ( mmol /l) Na + 90 75 K + 20 65 Cl - 80 20 Citrate 10 10 Glucose 111 111 Osmolality 311mosm/l 245mosm/l

26. TYPES OF DEHYDRATION Classification based on: Fluid volume depletion - Mild, - Moderate and - Severe dehydrations Plasma tonicity [ osmolality ] - Hypotonic, - Isotonic and - hypertonic dehydrations Sodium deficit: - Hyponatraemic [10-15 %], - Isonatraemic [70 %] and - Hypernatraemic [10-15 %] dehydrations

27. Clinical features of dehydration 27 From Lissauer & Graham 2002