DEHYDRATION Dr Nadeem Zubairi Dehydration 2 million infants

DEHYDRATION Dr Nadeem Zubairi

Dehydration 2 million infants and children die every year in the developing countries

Case Study-- Basim is 4 years old and his brother, Ahmad, is 5 months old. Both children are brought to the clinic by their mother because of diarrhea and fever of 4 days duration. Basim has also vomited thrice. Doctor assesses the children and determines that Basim is severely dehydrated but Ahmad is only mildly dehydrated. Basim`s serum sodium is 170 m. Eq/L while that of Ahmad is 142 m. Eq/L

Case Study. Abdul. Aziz is a 40 days old first born child who is having vomiting since second week of life. He tends to vomit almost all of the milk taken immediately after the feed and gets hungry again. Examination reveals that he is moderately dehydrated and there is an olive size mass in epigastric region. CBC is unremarkable. Electrolytes: Na 131, K 3. 0, Cl 95, bicarb 32. PH 7. 45.

Case Study. Abdul. Rahman, A 14 -year-old male is brought to the Emergency Department via ambulance with a report of the patient being found unresponsive. He is a known case of Type 1 DM and is on Insulin since last 7 years. Lately he was running fever and mother is not sure about regularity of doses during this illness. On examination Abdul. Rahman has altered consciousness level, acidotic breathing and has severe dehydration. Labs: TLC……… high Sugar…… 402 mg/dl PH……… 7. 15 Ketone bodies ++++

Case Study- Rehana is a 5 year old child who had 60% burns following spillage of boiling water on trunk and lower limbs 02 days back. She is in the hospital. Lately she is febrile, intake is less, tongue is dry. Her urine output is less and she is hypotensive.

WHAT IS COMMON IN ALL ? DEHYDRATION

OBJECTIVES At the end of this lecture you will able to know the followings: *What is dehydration? *What are the causes of dehydration? *The clinical manifestaions of dehydration. *The investigations required. *Management of dehydration.

Distribution of Body Water Intravascular ECF Na+ Cl- ICF K+ Interstitial Intracellular

Fluid composition varies at different ages

% of Water in the Body

Fluid Maintenance Body Wt Fluid per day 0 – 10 kg 100 ml/kg 11 -20 kg 50 ml/kg Ø 20 kg 20 ml/kg

e. g. a child of 25 kg First 10 kg = 1000 ml Second 10 kg = 500 ml Remaining 5 kg = 20 ml Total i. e. per hr = 1700 ml/ pay = 70 ml/ hr

Fluid Losses in Infants LUNGS URINE, FECES SKIN

Differences between children & adults ©Surface Area (BSA) ©Metabolic Rate ©Kidney Function ©Fluid Requirements

Reasons why infants & children are at > risk for developing fluid & electrolyte imbalance ©Increased % of body weight is H 2 O ©Large volume of ECF ©Increased BSA (insensible loss) ©Increased Metabolic rate ©Immature Kidneys

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 (e. g. ascites, effusions), or capillary leak of fluid (e. g. burns and sepsis).

CAUSES OF DEHYDRATION

Conditions causing Fluid Imbalances ©Phototherapy ©Increased RR ©Fever ©Vomiting ©Diarrhea *(Gastroenteritis)* ©Drainage tubes, blood loss ©Burns

Diarrhea © Metabolic Acidosis © loss of HCO 3 from G. I. Tract © p. H © HCO 3 © Treatment: Correct base defecit, replace losses of with Na. HCO 3

Vomiting © Metabolic Alkalosis © Loss of acid from stomach © p. H © HCO 3 H+ © © Treatment: Prevent further losses and replace lost electrolytes Example: Pyloric Stenosis

Heat stroke

Fever © Each degree of fever increases basal metabolic rate (BMR) by 10%, with a corresponding fluid requirement

Phototherapy Infant under phototherapy. Note that the eyes are shielded and a diaper is used to contain the diarrheal stools. Copyright © 1999, Mosby, Inc.

Mouth ulcers, stomatitis, pharyngitis, tonsillitis: pain may severely limit oral intake

Burns © Fluid loss is 5 -10 X greater than from undamaged skin © Abnormal exchange of electrolytes between cells and interstitial fluid

Burns: fluid losses may be extreme and require aggressive fluid management

Diabetic ketoacidosis (DKA).

Congenital adrenal hyperplasia: may have associated hypoglycaemia, hypotension, hyperkalaemia, and hyponatraemia.

Cystic fibrosis: excessive sodium and chloride losses in sweat. Diabetes insipidus: excessive output of very dilute urine. Thyrotoxicosis: increased insensible losses and diarrhoea.

Drainage Tubes/ Blood loss

ASSESSING DEHYDRATION IN CHILDREN

Manifestations of ECF Deficit (Dehydration) ©S & S ©Weight loss ©Blood pressure drop ©Delayed capillary refill ©Oliguria ©Sunken fontanel ©Decreased skin turgor © Physiologic Basis ©Decreased fluid vol. ©Inadequate circ. Blood ©Decreased vascular volume ©Inadequate kidney circ. ©Decreased fluid volume ©Decreased interstitial fluid

Degree of Dehydration ©Mild dehydration (3 -5%) ©Moderate dehydration (6 -10%) ©Severe dehydration (10 -15%)

Mild Moderate Severe 6 -10% More than 10% Active, alert Irritable, alert, thirsty Lethargic, looks sick Capillary Normal filling (compared to your own) Slightly delayed Delayed Weight loss Up to 5% Appearance Pulse Normal Fast, low volume Very fast, thready Respiration Normal Fast and deep Blood pressure Normal or low Orthostatic hypotension Very low Mucous memb. Moist Dry Parched Tears Present Less than expected Absent Eyes Normal Sunken Normal

Capillary filling (compared to your own) Normal Slightly delayed Delayed Pulse Normal Fast, low volume Very fast, thready Respiration Normal Fast and deep Blood pressure Normal Mucous memb. Moist Dry Parched Tears Present Less than expected Absent Eyes Normal Sunken Pinched skin Springs back Tents briefly Prolonged tenting Fontanel (infant sitting) Normal Sunken slightly Sunken significant ly Urine flow Normal Reduced Severely reduced Normal or low Very low Orthostatic hypotension

Earliest Detectable Signs ©Tachycardia ©Dry skin and mucous membranes ©Sunken fontanels ©Circulatory Failure (coolness, mottling of extremities) ©Loss of skin elasticity ©Delayed cap refill

Skin turgor is assessed by pinching the skin of the abdomen or thigh longitudinally between the thumb and the bent forefinger. The sign is unreliable in obese or severely malnourished children. Normal: skin fold retracts immediately. Mild or moderate dehydration: slow; skin fold visible for less than 2 seconds.

Mild or moderate dehydration: slow; skin fold visible for less than 2 seconds. Severe dehydration: very slow; skin fold visible for longer than 2 seconds. Other features of dehydration include dry mucous membranes, reduced tears and decreased urine output. Additional signs of severe dehydration include circulatory collapse (e. g. weak rapid pulse, cool or blue extremities, hypotension), rapid breathing, sunken anterior fontanels

Loss of Skin Elasticity due to dehydration is not a reliable sign in malnourished children

What is considered oliguria in an infant or child? ©<1 ml/kg/hr

How would you measure U. O. for a child who is not toilet trained? ©Weigh diaper © 1 gram = 1 cc

TYPES OF DEHYDRATION

Dehydration = Total Out > Total In © Types: © Isotonic ©Electrolyte = Water © Hypotonic ©Electrolyte > Water © Hypertonic ©Water > Electrolyte

The most common type of dehydration in children is…. . ©Isotonic

Hypernatremic dehydration © Dehydration, characterized by increased concentrations of sodium and chloride in the extracellular fluid, it results from diarrhea in infants. © The occurrence of the hypernatremia and hyperchloremia lies in the relatively greater expenditure of water than electrolyte via skin, lungs, stool and urine. The water deficit in these infants is primarily intracellular. © The majority of infants with this type of dehydration show varying degrees of depression of central nervous system varying from lethargy to coma. Convulsions are frequently observed. © Dilute solutions of electrolyte are indicated in rehydration. Rapid adjustment, however, appears to accentuate the CNS disturbance. Rehydration is best carried out slowly over a 2 - to 3 -day period.

HYPERNATREMIC DEHYDRATION Major danger due to condition: Brain hemorrhage. . . shrinkage of brain leading to tearing of vessels Major danger due to treatment: Brain edema due to movement of water into the brain cells. Occurs if treatment is too rapid

What lab tests provide useful information when the concern is dehydration? Usually no tests are needed if child is clinically stable CBC, Urea Electrolytes, Blood gases Stool RE and C/S

MANAGEMENT OF DEHYDRATION

Management of Mild to Moderate Dehydration © Oral Rehydration ©Pedialyte ©Infalyte ©Rehydralate ©Rules regarding rehydration © 50 -100 ml/kg within 4 hours

Home Management

Oral Rehydration v. Oral fluids commonly given to children when sick: v. Apple juice (low Na, High K) v. Coke (Low Na, Low K, High sugar) v. Pepsi (Na—little better than Coke, no K) v 7 -Up (sugar, small Na, no K) v. Gatorade (high Na, sugar) v. Grape juice (low Na, high K) v. Orange juice (low Na, High K) v. Milk (has Na, K, Cl, HCO 3)

ORAL REHYDRATION SOLUTION (ORS)

ORS Developed 1940 s in Dhaka Bangladesh

ORS Most important medical discovery of the 20 th century

ORS 5 million deaths / year After ORS 2 million deaths / year

ORS components WHO/UNICEF Na = 90 mmol/l k = 20 mmlo/l cl = 80 mmol/l glucose = 111 mmol/l Osmol = 311 mmol/l

WHO vs. Hypo-osmolar ORS WHO/UNICEF Na = 90 mmol/l k = 20 mmlo/l cl = 80 mmol/l glucose = 111 mmol/l Osmol = 311 mmol/l Hypo-osmolar Na = 60 mmol/l k = 20 mmlo/l cl = 50 mmol/l glucose = 84 mmol/l Osmol = 224 mmol/l

Hypo-osmolar ORS Many studies support the use of reduced osmolarity ORS but the debate is not resolved. It is preferred in severely malnourished (marasmic) child as the standard (old) WHO ORS may cause hypernatremia

ORT vs. I/V Therapy ORT is as effective as I/V fluid for rehydration of moderately dehydrated children due to G/E in the E/D. ORT Demonstrated no inferiority for successful rehydration at 4 hours and hospitalization rate. A randomized controlled trial by P Spandorfer et al Pediatrics Feb. 2005

ORT vs. I/V Therapy Although no clinically important differences between ORT and IVT, the ORT group did have a higher rate of paralytic ileus, and the IVT group exposed to risk of intravenous therapy. For every 25 children treated with ORT one fail and require IVT L Hartlig The Cochrane Database of Systematic Reviews 2006 Issue 4

Reluctance to use ORT ?

Reluctance to use ORT ©People do not consider ORT high-tech enough. ©Physicians prefer I/V fluids. ©It takes time to educate parents re ORT. ©Time consuming for busy parents.

Moderate to Severe Dehydration Management

Goals of IV Therapy ØExpand ECF volume and improve circulatory and renal function (Isotonic solution. 9%NS, LR, D 5 W) ØK+ after kidney function is assessed ØBegin oral feedings

MANAGEMENT OF DEHYDRATION -Replace Phase 1: Acute Resuscitation : © Give Lactated Ringer OR Normal Saline at 10 -20 ml/kg IV over 30 -60 minutes. © May repeat bolus until circulation stable -Calculate 24 hour maintenance requirements © Formula: © First 10 kg: (100 cc/kg/24 hours) © Second 10 kg: (50 cc/kg/24 hours) © Remainder: (20 cc/kg/24 hours) Example: 35 Kilogram Child © Daily: 1000 cc + 500 cc + 300 cc = 1800 cc/day -Calculate Deficit: © Mild Dehydration: (40 ml/kg) © Moderate Dehydration: (80 ml/kg) © Severe Dehydration: (120 ml/kg)

MANAGEMENT Continue -----Calculate remaining deficit: © Substract fluid resuscitation given in Phase 1 -Calculate Replacement over 24 hours: © First 8 hours: 50% Deficit + Maintenance © Next 16 hours: 50% Deficit + Maintenance © Determine Serum Sodium Concentration © Hypertonic Dehydration (Serum Sodium > 150) © Isotonic Dehydration © Hypotonic Dehydration (Serum Sodium < 130) © Add Potassium to Intravenous Fluids after patient voids urine © Potassium source © Potassium Chloride © Potassium Acetate for Metabolic Acidosis © Potassium dosing © Weight <10 kilograms: 10 meq KCl /liter glucose © Weight >10 Kilograms: 20 meq KCl /liter glucose

Table of Commonly Used IV Solutions Name of Solution 0. 45% Sodium Chloride Shorthand Notation: ½NS 0. 9% Sodium Chloride Shorthand Notation: NS Type of Solution Ingredients in 1 -Liter Uses Complications Hypotonic p. H 5. 6 77 m. Eq Sodium 77 m. Eq Chloride hypotonic hydration; replace sodium and chloride; hyperosmolar diabetes if too much is mixed with blood cells during transfusions, the cells will pull water into them and rupture Isotonic p. H 5. 7 154 m. Eq Sodium 154 m. Eq Chloride isotonic hydration; replace sodium and chloride; alkalosis; blood transfusions (will not hemolyze blood cells) None known Hypertonic p. H 5. 0 513 m. Eq Sodium 513 m. Eq Chloride 3% Sodium Chloride 5% Dextrose in Water symptomatic hyponatremia due to excessive sweating, vomiting, renal impairment, and excessive water intake Hypertonic p. H 5. 8 855 m. Eq Sodium 855 m. Eq Chloride Isotonic p. H 5. 0 5 grams dextrose (170 calories/liter) isotonic hydration; provides some calories Hypertonic p. H 4. 3 10 grams dextrose (340 calories/liter) may be infused peripherally; hypertonic hydration; provides some calories Hypertonic p. H 4. 4 5 grams Dextrose 34 m. Eq Sodium 34 m. Eq Chloride fluid replacement; replacement of sodium, chloride and some calories rapid or continuous infusion can result in hypernatremia or hyperchloremia Shorthand Notation: D 5 W 10% Dextrose in Water Shorthand Notation: D 10 W 5% Dextrose in 1/4 Strength (or 0. 25%) Saline Shorthand Notation: D 5¼NS water intoxication and dilution of body's electrolytes with long, continuous infusions vein irritation because of acidic p. H, causes agglomeration (clustering) if used with blood transfusions; hyperglycemia with rapid infusion leading to osmotic diuresis

Lactated Ringer’’s (RL): Isotonic, 273 m. Osm/L. Contains 130 m. Eq/L Na+, 109 m. Eq/L Cl--, 2 m. Eq/L lactate, and 4 m. Eq/L K+. Lactate is used instead of bicarb because it’’s more stable in IVF during storage. Lactate is converted readily to bicarb by the liver. Has minimal effects on normal body fluid composition and p. H. More closely resembles the electrolyte composition of normal blood serum. Does not provide calories. Contra-indication: Pyloric stenosis(metabolic alk)

Why is it necessary to use a pump or other volume control when infusing Ivs into children? ©Avoid overload ©Specifically monitor input

When to resume normal diet?

Special Considerations Antibiotics Anti- emetics Anti-diarrheal agents Antimotility drugs, slow intestinal transit but have little effect on the total stool volume and may have serous side effect including ileus. They are not advised for infants or children

Case Study-- Basim is 4 years old and his brother, Ahmad, is 5 months old. Both children are brought to the clinic by their mother because of diarrhea and fever of 4 days duration. Basim has also vomited thrice. Doctor assesses the children and determines that Basim is severely dehydrated but Ahmad is only mildly dehydrated. Basim`s serum sodium is 170 m. Eq/L while that of Ahmad is 142 m. Eq/L

Ahmad…. . Mild dehydration Weight…. . 7 kgs Isonatremic ORS Basim……. Severely dehydrated Weight……. 15 kgs Hypernatremic Total deficit: 15 X 100 -120=1500 - 1800 ml Type of fluid: 0. 45% Normal Saline Duration of therapy: 48 to 72 hours Frequent check