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Nutrition & Fluids. Dr. D. Barry. 1) Calories. Requirements Growth Type of feeding Supplements. Calorie Requirements for Normal Growth. Neonatal Calorie Requirements. Normal Weight Gain. The Diet/Feeding History. What? How often? How much? How long to feed?
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Nutrition & Fluids Dr. D. Barry
1) Calories • Requirements • Growth • Type of feeding • Supplements
The Diet/Feeding History • What? • How often? • How much? • How long to feed? • Specific feeding concerns? • Lactose free? Soya? Etc. • Any additions / supplements? • Previous feeds & why changed? • Growth?
Normal Feeding Patterns 1) Neonate; Breast / Formula 2) 4-6/12; begin introduce solids • Important developmental milestones 3) 6/12; follow-on formula / continue breast-feeding 4) 1 year; 3 meals +/- snacks • Bottle; Cow’s Milk Bottle (not until > 1 year)
Special Feeds • Lactose-free • For lactose intolerance • Profuse watery diarrhoea (eg post-gastro) • Can give Soya • Hydrolysed (pre-digested protein) • For allergy/intolerence to Cow’s milk Protein • Soya not recommeded as X-reactivity
Nutritional Supplements • Vitamin K: Prevents hemorrhagic disease of the newborn. Injected into all infants at birth. • Vitamin B12: Only necessary for exclusively breastfed babies of vegan mothers. • Iron • Vitamin D
Nutritional Supplements: Vitamin D • Required to prevent rickets • Supplemented in all standard infant formulas • Not found in adequate supplies in breast milk • Consider supplementation in exclusively breastfed infants with low sun exposure
Nutritional Supplements: Iron • Prevent Iron-def. Anemia. • Supplemented in all standard infant formulas. (Beware the low-iron brands!) • Good supply in breast milk – also more bioavailable. • NOT adequate amounts in cow’s milk
Introduction of Solid Foods Normal, healthy infants do not require any nutrition besides breast milk or formula until 4-6 months. Why not earlier? • Head control lacking • Calories sufficient Why not later? • Oral motor skills important early in development • Protein/Iron/Zinc needs increase • Total caloric need increases
Introduction of Solid Foods • Weaning to solids begins with mineral fortified cereals (iron and zinc) and advances to other foods. • Start with single grain cereals (rice, oatmeal, barley). • When starting new foods (pureed fruits, vegetables or meats) offer single items sequentially to identify any food allergies • Avoid peanuts, eggs, fish or other common allergenic foods • Avoid Honey < 2 years; risk botulism
Why No Cow’s Milk Before One Year of Age? • Iron Deficiency Anemia • Low iron content of cow’s milk • Replaces other iron sources in the toddler’s diet • Possible allergic colitis – GI blood loss • Allergic Potential • Immune system less robust, higher risk of cow’s milk protein allergy and eczema before 1 year
The Child with a Chronic Disease • Higher metabolic needs: • Cerebral Palsy with Spasticity • Congenital Heart Disease • Lower metabolic needs: • Hypotonia • Special diets: • Cystic Fibrosis • Celiac • Diabetes • PKU
General Advise Parents • < 1 food treat / week • Low-fat milk after age 2 • Healthy balanced diet better than supplements • Exercise
2) Fluids • Physiology • Requirements • Dehydration • Calculations • Methods of Replacement • Electrolytes • Types of IV
Fluids; Basic Physiology • Human Body is 60% Water • 40% protein, minerals, fat & carbohydrate (little) • Term Infant 75% water • Premature Baby 80% water • 75% 60% by 12 months old
Blood volume • Blood volume is 8% - 10% of body weight • 2 kg newborn has 200mls of blood • 600g premature baby has 60mls of blood • 10kg child has 800 1000mls of blood
Physiology • Children (particularly Infants) are sensitive to changes in TBW • Young infants have poor urine concentrating ability therefore get dehydrated faster • Volume of TBW can be altered by dehydration, anaemia, Heart Failure, abn osmolality, hypoalbuminaemia etc. • More vulnerable to electrolyte imbalances
When Do You Need to Consider Administering Fluids? • NPO (eg. Pre-op, intra-op) • Intake insufficient to replace ongoing losses (eg. Ileostomy / severe diarrhoea / DI / salt-losing crises etc.) • Dehydration; mild / mod / severe • ↓ intake; systemic illness / resp dx in infant • ↑ losses; vomiting / diarrhoea (eg. G/E), insensible losses, shock (DD of causes)
IV vs. PO fluids • If tolerating PO – can give PO (or NG) • ORS / dioralyte / Water etc. • Indications IV • Not tolerating adequate oral intake (eg. GE) • Mod – Severe Dehydration • NPO (? Pre-op) • Burns / Post Operative / DKA etc • Correcting Significant Electrolyte abnormalities
Oral Fluids • Oral fluids are much more Physiological than IV Fluids • Most cases of gastroenteritis can be treated with Oral Fluids • Depending on Clinical history, examination and severity of dehydration • Can use PO + IV concurrently
IV Fluids • Maintenance • (calculated per weight) • Maintenance + Deficit • (if dehydrated; as % of TBW est) • Maintenance + Replacement • (if ongoing losses; diarrhoea / ileostomy etc) • Check U&E for electrolyte imbalances
Calculating Fluid Requirements • Obtain weight; weigh the child or estimate • Assess Hydration status (as % TBW) • Assess/measure ongoing losses • Consider cause of dehydration/losses & treat • Calculate MAINTENANCE • Calculate DEFICIT ie rehydration required • Calculate REPLACEMENTS • Add up total & administer over 24 hours min. • Choose fluid type; ie ? Sugars ? electrolytes
Estimating weight • Full term; 3.5kg average (2.5 - 4.5kg) • By 1 year; 10 kg • 1-10 years; • Wt = 2 (age + 4)[APLS guidelines] • Eg. 5 year old; est. wt = (5 + 4) x 2 = 18kg
Calculating Maintenance IV Fluid Requirements • 0- 10 Kg; 100mls/Kg/day • 11 – 20 Kg; (1000mls for 1st 10kg as above) + 50mls/Kg/day(for each kg >10kg) • > 20 Kg; (1500mls for 1st 20kg as above) + 20mls/Kg/day(for each kg >20kg) • E.g. 23 Kg child 1000 + 500 + 60 = 1560mls/day = 65mls / hour
Q. • Calculate maintenance for 16kg child (20/12 old)… • Calculate maintenance for 38kg child (11 year old)…
Fluid Deficit • Who has a fluid deficit; • Dehydration eg Gastroenteritis / ↓ intake • Burns • Post Operative • DKA • Some conditions show intravascular depletion with oedema eg. Hypoalbuminaemia etc.
Assessing Hydration Status ¶; normal output; 1-2 ml / kg / hour * % of total body weight
Emergency Fluids • IV Bolus; 10 – 20 ml / kg Normal Saline • For Mod – Severe deyhydration • In shock – can repeat ++ • Resus management • This is NOT rehydration fluids! • When Stable; Maintenance + Deficit + Replacements Calculate for 24 hour period minimum
Calculating Rehydration Fluids • Clinical assessment % TBW • 5% (50ml/kg) of 23kg (23000g) child = 1150ml • 10% (100ml/kg) of 23kg child = 2300ml • Replace over 24-72 hours • Check U&E • Add to Maintenance (1560ml/day if 15kg child) • If over 48 hours; 1560 + 1560 = 3120ml • + 2300ml (mod./ 10% dehydrated) • = 5420ml over 48 hours = 113ml/hr x 48 hrs • Which fluid to use?
Urine Output • Normal output 1-2ml/kg/hr minimum • Catheterised • Weigh wet nappies (reliable indicator if uncontaminated) • Input/output chart, +/- daily weights • If reduced output – assess hydration status; clinical signs & vitals • ? Dehydrated ? Overloaded • palpate bladder ? Full ? obstruction
2 year old Poor intake Dry MM, Eyes & fontanelle sunken No wet nappy all day HR 180 bts/min Extremities cool What’s est. weight? What’s % dehydration? Immediate management? Fluid Replacement? Q.
Colloids Larger insoluble molecules blood a colloid Albumin(4.5%, 20%) gelatin (Gelofusine), Remain intravascular for between 1 and 4 hours depending on the solution used Treatment shock / ongoing intravascular depletion Crystalloids Aqueous solutions of mineral salts or other water-soluble molecules. Often close to the concentration in the blood (isotonic) normal saline, 0.9%NaCl Hartman’s Solution Ringer's lactate(isotonic solution often used for large-volume fluid replacement) IV Fluids; choices
IV Fluids; which to choose? • Colloids if intravascular depletions / shock • Crystalloids for Maintenance fluids & Rehydrating deficits as discussed above • Hypotonic / Isotonic / Hypertonic? • Electrolyte conc; Na / K • Sugar content; dextrose ? 2.5% / 5%
Maintenance IV Fluid Requirements • Neonates; 5 – 10% dextrose • cannot tolerate fasting • Hypoglycaemic if no sugar source • Infants <10kg; 2.5% Dex + 0.9% NaCl • > 10 kg; Hartman’s / O.9% NaCl
U & E • Na (135 – 145); [requirement; 2–3 mmol/Kg/day] • May be hyponatraemic (<130) or hypernatraemic (>150) with dehyration • Choose replacement fluid & speed of replacement accordingly • K (3.5 – 5.0); [requirement; 1–2 mmol/Kg/day] • Often hypokalaemic if vomiting / diarrhoea • Add to IV fluids eg. 10mmol/1L IV fluids • Seldom need to be added if any PO intake
Hypernatraemic DehydrationSodium > 150 • Too Much Salt or Not enough Water • Intra- cellular loss greatest • Use 0.45% NaCl, • Correction MUST BE SLOW; 48-72 hours • If Sodium falls too rapidly, it leads to re-expansion of intra-cellular space too quickly Odema------ Particularly of Brain cells
Hyponatraemic Dehydration Sodium < 130 • Sodium losses exceed water losses • Fluid goes from extra intracellular odema • Can cause convulsions • Use 0.9% NaCl • Ideally replace slowly, but if seizing, may have to do over 24hours (very careful monitoring)
IV fluids complications • IV fluids are a medication • Must be prescribed by Doctors (ie. YOU!!!) • Side-effects; • Electrolyte imbalances • Potentially letal if wrong fluid or duration • Eg cerebral oedema if correct hypernatraemic dehydration too quickly • Eg. Fatal arrhythmias with K replacement • Overload
Overload • Oedema; sacral, scrotum, periorbital, (+/- ankle) • CVS; ↑ JVP, ↑ BP, tachycardic • Heart failure, Pulmonary Oedema, hepatomegaly, ascites • ↑ weight
Summary; Fluids • Know how to assess Hydration • Know to calculate maintenance & deficit • Know to consider electrolytes; • Na, K & Dex when administering IV +/- other • Know complications of IV fluids • PO is best if possible
4 yr old boy Vomiting & Diarrhoea x 2/7 Not tolerating anything today; vomiting! Wet nappies Dry tongue, lips Normal skin turgor Miserable but alert HR 100 bpm, BP 90/60 What do you do? Final Q.