Assessment and management of dehydration

Assessment and management of dehydration

1. ASSESSMENT AND MANAGEMENT OF DEHYDRATION Dr. Siddharth Mahajan Guide – Dr. Ashish Vaidya 21/07/2016

2. INTRODUCTION: Dehydration resulting from acute diarrheal illness is one of the most significant causes of morbidity and mortality in the population. I n some cases, it accounts for more than 50% of the deaths during the initial stages of a humanitarian emergency. Worldwide, over 3 million children under 5 years die from dehydration every year. (WHO) The use of oral rehydration therapy ( ORT ) has markedly reduced the morbidity and mortality associated with dehydration caused by diarrheal illness regardless of the etiology.

3. Lobo ND, Lewington AJP, Allison SP. Basic concept of fluid and electrolyte therapy. Page no-20-30

4. Body Fluid Volumes Lobo ND, Lewington AJP, Allison SP. Basic concept of fluid and electrolyte therapy. Page no-9-23

5. Normal anatomy and physiology Water comprises 60% of the body weight of an average adult although the percentage is lower in obesity, since adipose tissue contains less water than lean tissue. The total body water is divided functionally Extracellular (ECF = 20% of body weight) Intracellular fluid spaces (ICF = 40% of body weight) These are separated by the cell membrane with its active sodium pump which ensures that sodium remains largely in the ECF chowdhury AH, Lobo DN. Fluids and gastrointestinal function. Curr Opin Clin Nutr Metab Care 2011;14:469-76

6. Body Water Compartments Related to Age

7. Intracellular and Extracellular Fluid Composition Intracellular ( mEq /L) Extracellular ( mEq /L) Na + 20 133-145 K + 150 3-5 Cl - --- 98-110 HCO 3 - 10 20-25 PO 4 3- 110-115 5 Protein 75 10 % Body weight 80 15 (Interstitial); 5 (Intravascular)

8. Composition of fluids (mmol/l) Lobo ND, Lewington AJP, Allison SP. Basic concept of fluid and electrolyte therapy. Page no-9-23

9. Normal routes of water gain and loss

10. WATER LOSSES

11. Disturbances of fluid homeostasis Disturbance of fluid balance (intake ≠output) Dehydraton, Overhydration (hyperhydration) Disturbance of osmolarity (electrolyte intake≠water intake) Isotonic Hypotonic Hypertonic Lobo ND, Lewington AJP, Allison SP. Basic concept of fluid and electrolyte therapy. Page no-9-23

12. DEFINITION : Dehydration is a condition that can occur with excess loss of water and other body fluids. Dehydration results from decreased intake, increased output (renal, gastrointestinal or insensible losses), a shift of fluid ( eg , ascites, effusions), or capillary leak of fluid ( eg , burns and sepsis).

13. Diarrhea Definition: An increase in the fluidity, volume and frequency of stools . (>3 times/ day) Acute diarrhea : Short in duration ( less than 2 weeks) . Chronic diarrhea : 2 weeks or more

14. Etiology of Diarrhea Acute Diarrhea Chronic Diarrhea Gastroenteritis Post infections Systemic infection Secondary disaccaridase deficiency Antibiotic association Irritable colon syndrome Overfeeding Milk protein intolerance

15. Types of Diarrhea Acute watery diarrhea: (80% of cases) Dehydration Malnutrition Dysentery: (10% of cases) Anorexia/weight loss Damage to the mucosa Persistent diarrhea: (10% of cases) Dehydration Malnutrition

16. Mechanisms of Diarrhea Osmotic Secretory Exudative Motility disorders

17. Mechanisms of Diarrhea Osmotic Defect present: Digestive enzyme deficiencies Ingestion of unabsorbable solute Examples: Viral infection Lactase deficiency Sorbitol /magnesium sulfate Infections Comments : Stop with fasting No stool WBCs

18. Mechanisms of Diarrhea Secretory: Defect: Increased secretion Decreased absorption Examples: Cholera Toxinogenic E.coli Comments: Persists during fasting No stool leukocytes

19. Mechanisms of Diarrhea Exudative Diarrhea: Defects: Inflammation Decreased colonic reabsorption Increased motility Examples: Bacterial enteritis Comments: Blood, mucus and WBCs in stool

20. Mechanisms of Diarrhea Increased motility: Defect: Decreased transit time Example : Irritable bowel syndrome

21. CLASSIFICATION OF DEHYDRATION SEVERITY BY WHO NO DEHYDRATION SOME  DEHYDRATION SEVERE DEHYDRATION Not enough signs to classify as some or severe dehydration Two or more of the following signs: restlessness, irritability sunken eyes drinks eagerly, thirsty skin pinch goes back slowly Two or more of the following signs: lethargy/unconsciousness sunken eyes unable to drink or drinks poorly skin pinch goes back very slowly (≥2 seconds) National Collaborating Centre for Women's and Children's Health (UK). Diarrhoea and Vomiting Caused by Gastroenteritis: Diagnosis, Assessment and Management in Children Younger than 5 Years. London: RCOG Press; 2009 Apr. (NICE Clinical Guidelines, No. 84.) 4, Assessing dehydration and shock.

22. Degree of Dehydration Factors Mild 3% (30ml/kg) 5% (50ml/kg) Moderate Older Child 6% (60ml/kg) Infant 10% (100ml/kg) Severe 9% (90ml/kg) 15% (150ml/kg) General Condition Well, alert Restless, thirsty, irritable Drowsy, cold extremities, lethargic Eyes Normal Sunken Very sunken, dry Anterior fontanelle Normal depressed Very depressed Tears Present Absent Absent Mouth + tongue Moist Sticky Dry Skin turgor Slightly decrease Decreased (1-2 sec) Very decreased (>2sec) Thirst Normal Drinks eagerly, thirsty Unable to drink or drinks poorly Pulse (N=110-120 beat/min) Slightly increase Rapid, weak Rapid, sometime impalpable BP (N=90/60 mm Hg) Normal Deceased Deceased, may be unrecordable Respiratory rate Slightly increased Increased Deep, rapid Urine output Normal Reduced Markedly reduced Treatment Plan A Plan B Plan C

23. Types of Dehydration Isonatremic Hypernatremic Hyponatremic Loses H 2 O = Na H 2 O > Na H 2 O < Na Plasma osmolality Normal Increase Decrease Serum Na Normal Increase Decrease ECV ICV Decrease maintained Decrease Decrease +++ Decrease +++ Increase Thirst ++ +++ +/- Skin turgor ++ Not lost (Doughy skin) +++ Mental state Irritable/lethargic Very irritable Lethargy/coma shock In severe cases Uncommon Common

24. Isonatremic Dehydration By far the most common Equal losses of Na and Water Na = 130-150 No significant change between fluid compartments No need to correct slowly

25. Hyponatremic Dehydration Sodium loss > Water loss Na <130mmol/L Water shifts from ECF to ICF Child appears relatively more ill Less intravascular volume More clinical signs Cerebral edema Seizure and Coma with Na <120 Increase rate of Sr. Na level should be less than 0.5 mEq/L (Central pontine myelinolysis) Lobo ND, Lewington AJP, Allison SP. Basic concept of fluid and electrolyte therapy. Page no-9-23

26. Hyponatremia : Decreased Weight Increased or Normal Weight Renal Losses Extra-renal Losses Na + losing nephropathy GI losses Nephrotic syndrome Diuretics Skin losses Congestive heart failure Adrenal insuffiency Third spacing SIADH Cerebral salt wasting syndrome Cystic Fibrosis Acute/ Chronic renal failure Water intoxications Cirrhosis Excess salt free infusions

27. Hypernatremic Dehydration Water loss > sodium loss Na >150mmol/L Water shifts from ICF to ECF Child appears relatively less ill More intravascular volume Less physical signs (Dry doughy skin/ Inc. muscle tone) Alternating between lethargy and hyperirritability D ecrease rate of Sr. Na level should be less than 0.5 mEq/L (Cerebral Edema) chowdhury AH, Lobo DN. Fluids and gastrointestinal function. Curr Opin Clin Nutr Metab Care 2011;14:469-76

28. Hypernatremia : Decreased Weight Increased or Normal Weight Renal Losses Extra-renal Losses Nephropathy GI losses Exogenous Na + Diuretics Skin losses Mineralocorticoid excess Diabetes insipidus Respiratory Hyperaldosteronism Post obstructive diuresis Diuretic phase of ATN

29. Approach to Dehydration Initial Resuscitation Determine % dehydration Define the type of dehydration Determine the type and rate of rehydration fluids Final considerations

30. Management of Dehydration General Principles: Supply Maintenance Requirements Correct volume and electrolyte deficit Replace ongoing abnormal losses

31. 1. Maintenance Volume: Calorie Calculations Basal Calorie Method Holliday- Segar method Body Surface area method

32. BASAL CALORIE METHOD

33. HOLLIDAY-SEGAR METHOD C AMY, BILLY S.A. Diagnosis and Management of Dehydration in Children. American Family Physician. 2009,oct;80(7):692-96.

34. BODY SURFACE METHOD: Should not be used in children < 10kg . STANDARD VALUES FOR USE IN BODY SURFACE AREA (BSA) METHOD H 2 O 1500 ml/m 2 /24 hr Na + 30-50 mEq /m 2 /24 hr K + 20-40 mEq /m 2 /24 hr m 2 = meters squared

35. 2. Deficit Repletion Water deficit Volume: Water Deficit (L) = Pre-illness weight (kg) - Illness weight (kg) % Dehydration = (Pre-illness weight – Illness weight)/ Pre-illness weight x 100 Each 1% dehydration corresponds to 10ml/kg fluid deficit

36. 3. Ongoing Losses Regardless of the degree of dehydration, give additional 10ml/ kg of ORS for each additional diarrheal stool.

37. Na + deficit ( mEq ) = fluid deficit (L) x proportion from ECF (0.6) x Na + conc. ( mEq /L) in ECF (145) K + deficit ( mEq ) = fluid deficit (L) x proportion from ICF (0.4) x K + conc. ( mEq /L) in ICF(150) Excess Electrolyte Deficits: mEq required = [conc. desired ( mEq /L) – conc. present ( mEq /L) x fluid deficit x weight

38. Free water deficit: 4ml/kg x pre-illness wt. (kg) (FWD) x [Conc. present ( mEq /L) – [Conc. desired ( mEq /L)] Solute fluid Deficit: Total fluid deficit – FWD (SFD) Solute Na + deficit = SFD (L) x 0.6 x 145 Solute K + deficit = SFD (L) x 0.4 x 150

39. 7 kg infant who has been ill for >3 days clinically appears 10% dehydrated. Current weight 6.3 kg. Na + =137mEq/L

40. Q. 7 kg (pre-illness weight) infant ill for > 3 days clinically appears 10% dehydrated. Current weight 6.3 kg. Serum Na + = 115 mEq /L

41. Q. 7 kg (pre-illness weight) infant ill for > 3 days clinically appears 10% dehydrated. Current weight 6.1 kg. Serum Na + = 160 mEq /L

42. Severe Dehydration Management of severe dehydration requires IV fluids. Choice of fluid: Normal saline(NS) or Ringer Lactate (RL) Fluid selection and rate should be dictated by The type of dehydration The serum Na Clinical findings Aggressive IV NS bolus remains the mainstay of early intervention in all subtypes

43. Monitoring Therapy Vital signs: Pulse Blood pressure Intake and output: Fluid balance Urine output Physical examination Weight Clinical signs of depletion or overload Electrolytes

44. WHO TREATMENT PLANS

45. Plan A (No Dehydration) Oral rehydration therapy to prevent Dehydration Age ORT fluids to give Amount of ORS to after each loose stool provide for use at home < 24 months 50 - 100 ml 500 ml/ day 2 – 10 years 100 – 200 ml 1000 ml/ day > 10 years Ad lib 2000 ml/ day Give Supplemental Zinc (10-20 mg) to the child, everyday for 10 to 14 days

46. Plan B (Some Dehydration) Daily fluid requirement: Up to 10 kg = 100 ml/ kg 10 – 20 kg = 50 ml/ kg > 20 kg = 20 ml/ kg Deficit replacement: 75 ml/ kg ORS to be given over 4 hours Replace losses: ORS should be administered in volumes equal to diarrheal losses. Maximum of 10 ml/ kg per stool. Give Supplemental Zinc (20 mg) to the child, everyday for 10 to 14 days

47. Plan C (Severe Dehydration) T reated with 20 mL / kg IV of isotonic crystalloid over 10 to 15 minutes . Repeat as necessary. Monitor pulse strength, capillary refill time, mental status, urine output and electrolytes. After resuscitation: A total of 100 ml/ kg of fluid given over 3 hours in children > 12 months and over 6 hours in children < 12 months. Assess the patient every 3 hours accordingly repeat Plan C or shift to Plan B Age 30 ml/ kg 70 ml/ kg < 12 months 1 hour 5 hour > 12 months 30 min 2 ½ hour

48. ORS Mechanism In normal physiological state, water is absorbed osmotically across the small bowel through tight junctions between epithelial cells due to a sodium gradient that is maintained by 2 mechanisms of sodium absorption in the brush border membrane of the luminal cell : passive sodium/ potassium diffusion active co-transport of sodium jointly with monosaccharides such as glucose. In diarrheal illness, the passive absorptive mechanism of sodium and chloride is impaired, but glucose absorption remains largely intact . This allows the absorption of enough water and sodium to compensate for fluid losses as significant as those seen in cholera.

49. ORS Constituent g/L Osmole / ion mmol / L Sodium chloride 3.5 Sodium 90 Glucose 20 Glucose 111 Potassium chloride 1.5 Potassium 20 Trisodium citrate 2.9 Citrate 10 Chloride 80 Total Osmolarity 311 Constituent g/L Osmole /ion mmol /L Sodium chloride 2.6 Sodium 75 Glucose 13.5 Glucose 75 Potassium chloride 1.5 Potassium 20 Trisodium citrate 2.9 Citrate 10 Chloride 65 Total Osmolarity 245 STANDARD WHO ORS LOW OSMOLARITY ORS

50. ADVANTAGES OF LOW OSMOLARITY ORS Promotes more effective water and sodium absorption. No additional risk for hypernatremia. Better acceptability due to taste Decreases volume, purge rate and duration of diarrhea. More stability of reconstituted solution. Single formulation promoted for all ages, irrespective of etiology or nutrition status.

51. Cereal based ORS/ Rice based ORS Super ORS Superior to WHO ORS in efficacy in patients with cholera. Similar efficacy in non- cholera diarrhea Advantages: Decreased purge rate Slow release of glucose from starch

52. Other types of ORS ReSoMal : Re hydration So lution in severely Mal nourished children with dehydration. Potassium deficiency but have high Sodium. Deficiency of magnesium, zinc and copper. Contents: Potassium: 40 mEq / L Sodium: 45 mEq / L Magnesium, zinc, copper.

53. Dehydration in Severe Malnutrition With some or severe dehydration but who are not shocked should be rehydrated slowly, either orally or by nasogastric tube. ReSoMal : Re hydration So lution in severely Mal nourished children should be used. 5ml/ kg Resomal every 30 mins for first 2 hrs. If still dehydrated, 5-10ml/kg/ hr should be given in alternate hours with F-75 for max 10 hrs. Signs of improved hydration status and overhydration checked every half hour for first 2 hrs then hourly.

54. Children with SAM and signs of shock or severe dehydration and who cannot be rehydrated orally or by NG tube should be treated with IV fluids 15ml/kg/hr. Half strength darrow’s soln. with 5% dextrose Ringer lactate solution with 5% dextrose. Monitor child every 5 – 10 mins for signs of overhydration and signs of CCF. If child does not improve with 1 hr of IV fluid, blood transfusion 10ml/kg slowly over 3 hours. WHO. Guideline: Updates on the management of severe acute malnutrition in infants and children. Geneva, World Health Organization; 2013

55. Other types of ORS Zinc fortified ORS ORS fortified with amino acids. Home made ORS 4g salt + 40g sugar in 1 L of water

56. Contraindications to ORT Ileus or intestinal obstruction Unable to tolerate (Persistent vomiting )

57. Home available fluids Acceptable Home available Fluids Fluids that contain Salt (Preferable) ORS, Salted drinks (Salted rice water/ salted yogurt drink), vegetable or chicken soup with salt Fluids that do not contain salt (Acceptable) Plain water, water in which cereal has been cooked, unsalted soup, yogurt drinks without salt, green coconut water, weak unsweetened tea, unsweetened fresh fruit juice Unsuitable home available fluids Commercial carbonated beverages, commercial fruit juices, sweetened tea.

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