1. Fluid, electrolyte and nutritional requirements for neonates Presented by : Maram Mobara

2. FEN Management in Neonates One of the essentials of neonatal care Many babies in NICU need IV fluids They all don’t need the same IV fluids (either in quantity or composition)

3. the body is composed mainly of water body water in early embryo represent 97% of body weight premature infants body water represent 80-90% of their weight newborn infant 77% adult 60% Things to consider: Normal changes in TBW, ECF

4. So, All babies are born with an excess of TBW, mainly ECF, which needs to be removed ECF in infant is 40%of body weight in adult 20% as the child grows,, there is muscle growth and cellular growth,, more water shifts from ECF to ICF compartment infant has less reserve of body fluid,, more likely to develop fluid volume deficits the infant needs more water due to ; 1.large body surface area 2.immature kidneys which cannot concentrate urine effectively high UOP

5. Things to consider: Insensible water loss (IWL) “Insensible” water loss is water loss that is not obvious through skin (2/3) or respiratory tract(1/3) depends on gestational age (more preterm: more IWL) depends on postnatal age (skin thickens with age: older is better --> less IWL) also consider losses of other fluids: Stool (diarrhea/ostomy), NG/OG drainage, CSF (ventricular drainage), etc

6. Management of F&E Goal: Allow initial loss of ECF over first week (as reflected by wt loss), while maintaining normal intravascular volume and tonicity (as reflected by HR, UOP, lytes, pH). Goal: Allow initial loss of ECF over first week (as reflected by wt loss), while maintaining normal intravascular volume and tonicity (as reflected by HR, UOP, lytes, pH). Subsequently, maintain water and electrolyte balance, including requirements for body growth. Subsequently, maintain water and electrolyte balance, including requirements for body growth. Individualize approach Individualize approach

7. TFI = Maintenance requirements (IWL+Urine+Stool water) + growth In the first few days, IWL is the largest component Urine: 60 cc/kg/day Stool: 5-10 cc/kg/day Growth: 20-25 cc/kg/day (since wt gain is 70% water)

8. Management of F&E (contd.) Guidelines for fluid and electrolyte therapy Fluid rate ml/kg/d electrolyte meq/kg/d Term infant 1 st day 2 nd &3 rd 4 th Dextrose10% 60-80 +10-20 +20 Sodium - 2-4* 2-4* Potassium - 1-2 * 2-4* 60-80ml/kg/day will provide 6-7 mg/kg/min of glucose

9. Factors modifying fluid requirement: Maturity --> Mature skin --> reduces IWL Elevated temperature (body/environment)--> increases IWL Humidity: Higher humidity --> decreases IWL up to 30% (over skin and over respiratory mucosa) Skin breakdown, skin defects (e.g. omphalocele)--> increases IWL (proportional to area) Radiant warmer --> increases IWL by 50% Plastic Heat Shield --> reduces IWL by 10- 30% Phototherapy --> increases IWL by 50%

10. Monitoring of fluid and electrolyte status; should be done daily for 1.body weight; loss >20%of birth weight during first week of life = uncompensated IWL, < 2% for first 4-5 days = excessive fluid administration 2.serum level of ; hematocrit, Na+,K+, BUN, creatinine, osmolarity, acidosis and base deficit,, if increased may indicate inadequate fluid tx 3.fluid input, output; UOP 3ml/kg/hr may indicate overhydration 4.general appearance and vital signs; hypotension, poor perfusion, poor pulses all are signs of inadequate fluid intake

11. Common electrolyte problems : Sodium: Hyponatremia (<127mEq/L) Hypernatremia (>145 mEq/L) Potassium: Hypokalemia (<3.5 mEq/dL) Hyperkalemia (> 5.5 mEq/dl) Calcium: Hypocalcemia (total<7 mg/dL; i<4) Hypercalcemia (total>11mg/dL; i>5)

12. Hyponatremia : < 127mEq/l Sodium levels often reflect fluid status rather than sodium intake

13. Management : If baby have seizure: Emergency 1. hypertonic saline solution (3% sodium chloride ) 2.Calculate deficit, give half over 12-24 hour 3.Rapid correction result in brain damage If due to volume over load : fluid restriction, decrease maintenance by 20 ml/kg/d If due to inadequate sodium intake: check formula 1.equation: desired level – (sodium value*weight*0.6( 2.Give for 12-24 hour

14. Hypernatremia: > 145 mEq/l Hypernatremia is usually due to excessive IWL in first few days in VLBW infants Increase fluid intake and decrease IWL. Rarely due to excessive hypertonic fluids Decrease sodium intake

15. Potassium is mostly intracellular: blood levels do not usually indicate total-body potassium pH affects K+: 0.1 pH change=>0.3-0.6 K+ change (More acid,more K;less acid, less K) ECG affected by both HypoK and HyperK: Hypok: flat T, prolonged QT, U waves HyperK: peaked T waves, widened QRS, bradycardia, tachycardia, SVT, V tach, V fib Potassium

16. Hypokalemia : < 3.5 mEq/dl arrhythmia ( Diuretics / digitalis ?) how much receiving by maintenance ? Diarrhea ? NGT tube output ? Ileus Repeat measurement Renal K+ ( Barrter’s syndrome) Blood gas level X-ray ECG Tx the cause, slow correction over 24 hr, decrease dose once reach high normal level

17. Hyperkalemia: > 5.5 mEq/dl How was the specimen collected ? How much is infant receiving ? ECG changes ? BUN & creatinine ? UOP? Blood gases ? Acidosis cause k+ to move out of the cell Tissue necrosis,NEC (x-ray)

18. Stop all fluids with potassium Calcium gluconate 1-2 cc/kg (10%) IV Sodium bicarbonate 1-2 mEq/kg IV Glucose-insulin combination Lasix (increases excretion over hours) kayexalate, potassium exchange resin 1g/kg/dose po/rectally (slow action) Dialysis/ Exchange transfusion

19. Metabolic alkalosis caused by electrolyte loss, specifically chloride, occur with prolonged gastric suction or vomiting and is easily corrected by replacement of the appropriate electrolyte So look for electrolyte loss espcially chloride and potassium and correct deficiet If due to prolonged suction, IV fluid transfusion with ½ normal saline + 20 meq kcl

20. Metabolic acidosis is usually the result of poor tissue perfusion and lactic acidosis. treat the underlying cause of the poor perfusion and by temporarily administering buffers, such as sodium bicarbonate, which is usually done when the pH falls below 7.3. use this formula to give the dose: NaHCO3 (mmol) = base excess x body weight (kg)/3

21. Hypocalcemia: total<7 mg/dL; i<4 Normal physiology: 3 rd trimester Ca from mother 1-2 days of life drop to 7.5 (loss of source, calcitonin) 3 rd day normal ca level (gradual increase in PTH) In ECF has 3 forms : bound to albumin / anions ionized 50% : impo. for coagulation, enzymes, cell membrane, neuromuscular excitability

22. Clinically ( DOESN’T correlate with severity) no symptoms Lethargy, Poor feeding, Vomiting, Abdominal distension Cyanosis, stridor Seizures Apnea Tetany and signs of nerve irritability, Chvostek sign, carpopedal spasm, Trousseau sign Prematurity, birth asphyxia ECG, prolonged QTc (>0.4 s), a prolonged ST segment, and T wave abnormalities may be observed

23. Causes of hypocalcemia Early neonatal hypocalcemia (48-72 h) Prematurity:. Birth asphyxia: renal insuff., metabolic acidosis,decreased PTH Diabetes mellitus in the mother : increased req. by macrosomic baby Late neonatal hypocalcemia (3-7 d) Exogenous phosphate load: feeding with phosphate-rich formula or cow's milk. Magnesium deficiency Transient hypoparathyroidism of newborn Hypoparathyroidism due to other causes

24. Management Screen high risk group (4 mg/kg/d of 10% calcium gluconate) symptomatic patient :Bolus Calcium gluconate (10% solution) is given IV at 1-2 ml/kg (100 mg/kg) slowly. Maintenance therapy is given at 200 mg/kg/day IV and increased as needed to maintain serum calcium level at 7 to 8 mg/dl. Should be diluted with 5% dextrose, under cardiac monitor ( bradyarrhythmia) in NICU Look for the cause : Mg :HypoCa may not respond to calcium therapy if hypoMg is not corrected (by 0.2ml/kg of 50 % solution ) low serum albumin concentration and abnormal pH Serum electrolytes and glucose (exclude) Phosphorus PTH

25. HYPOGLYCEMIA Blood sugar level < 40mg/dl -----  2.2mmol Send for lab result Is infant symptomatic? apnea, hypotonic, cyanosis, seizures, lethargy, temp. instability How much is infant receiving? Normal requirement 6mg/kg/hr Possible causes: Premature ( decrease glycogen stores), IUGR Diabetic mother( b cell hyperplasia), Beckwith W. syndrome, tumors Sepsis Hypothermia Asphyxia Endocrine disorders

26. Plan Maintain NORMOglycemia Send for baseline glucose level Asymptomatic w glucocheck < 25 mg/dl IV access Give glucose 6mg/kg/hr Check every 30 min Increase gradually until NORMO Bolus # in asymptomatic (rebound hyper) Glucocheck 20-40mg/dl Feeding w D5W Check every 30 min If stays low start infusion 6mg/kg/hr

27. Symptomatic patient : Baseline serum level Infusion of2-4 ml/kg of 10% glucose solution over 2-3min Continuous infusion at rate of 6-8ml/kg/min Check every 30 min Until 40 mg/dl serum glucose level Maintain normoglycemia

28. Goals: Normal growth and development Nutrient requirements: Energy Carbohydrate WaterMinerals ProteinVitamins Fat Trace elements

29. Nutritional requirements in the neonates : Calories : 50-60 kcal/kg/day to maintain weight 100-120 kcal/kg/day to gain weight Carbohydrates: 11-15g/kg/d (40-50% of total calories) Proteins: 2.25-4 g/kg/d (7-15% of total calories) Fats: 4-6g/kg/d (< 50% of total calories) Vitamins: requirements are not clearly established. Vitamin supplementation depends on the formula needed.

30. Energy needs: depend upon age, weight, maturation, caloric intake, growth rate, activity, thermal environment, and nature of feeds. Stressed and sick infants need more energy (e.g. sepsis, surgery) Parenteral nutrition need less energy (less fecal loss of nutrients, no loss for absorption): 70-90 Cal/kg/day + 2.4-2.8 g/kg/day Protein adequate for growth Count non-protein calories only! Protein to be preferred used for growth, not energy 65% from carbohydrates, 35% from lipids ideal

31. How to be organized ? To calculate a neonate’s F,E,& N: First calculate the amount of fluid (Water) plan how to give it: Parenteral (IV) or Enteral (OG/PO) calculate the amount of energy required Decide how to provide the energy: amount and nature of carbohydrates and lipids Provide proteins, vitamins, trace elements

32. Carbohydrate IV: Dextrose 3.4 Cal/g = 34 Cal/100 cc of D10W. Tiny babies are less able to tolerate dextrose. If blood levels >150-180 mg/dL, glucosuria=> osmotic diuresis, dehydration Insulin can control hyperglycemia Hyper- or hypo-glycemia => early sign of sepsis Avoid Dextrose>12.5% through peripheral IV

33. Carbohydrate (cont.) Enteral: Human milk 20 Cal/oz formula = 67 Cal/100 cc Lactose is carbohydrate in human milk and term formula. Soy and lactose free formula have sucrose, maltodextrins and glucose polymers Preterm formula has 50% lactose and 50% glucose polymers (lactase level lower in premies, but glycosidases active)

34. Fat Parenteral: 20% Intralipid (made from Soybean) better than 10% High caloric density Start low, go slow (0.5-3 g/kg/day) Avoid higher amounts in sepsis, jaundice, severe lung disease Maintain triglyceride levels of 200-300 mg/dL

35. Fat (cont.) Enteral: Approximately 50% of the calories are derived from fat. >60% may lead to ketosis. Medium-chain triglycerides (MCT) are absorbed directly. Preterm formula have more MCT for this reason. At least 3% of the total energy should be supplied as EFA

36. Proteins: 2.25-4 g/kg/d (7-15% of total calories) Restrict in stressed infants or infants with cholestasis to 1.5 g/kg/day Very high protein intakes (>5-6 g/kg/day) may be dangerous

37. Minerals (other than Na,K, Cl) Calcium & Phosphorus: Third trimester Ca accretion (120- 150mg/kg/day) and PO4 (75-85 mg/kg/day) is more than available in human milk. Hence, HMF is essential. Premie formula has sufficient Ca/PO4. Magnesium: sufficient in human milk & formula Iron: Feed Fe-fortified formula. Start Fe in breast feed infants at 4 months of age, and in premies once full feeds are reached.

38. Vitamins Fat soluble vitamins: A, D, E, K Water soluble vitamins: Vitamins B1,B2, B6, B12, Biotin, Niacin, Pantothenate, Folic acid, Vitamin C All neonates should get vit K at birth Term neonates: No vitamin supplement required, except perhaps vit D Preterm: Start vitamin supplements once full feeds established if on human milk without HMF. No need if on human milk with HMF, or preterm infant formula.

39. Trace elements Zinc, Copper, Selenium, Chromium, manganese, Molybdenum, Iodine Most preterm formulas contain sufficient amounts Fluoride supplementation not required in neonatal period

40. Postoperative Feeding : Neonates have most difficulty in feeding the work of feeding accounts for most of a neonate caloric expenditure, and a stressed neonate tires easily For this reason, gavage or gastrostomy tube feedings are generally employed for the early stages of postoperative feeding in neonates. evidence that the bowel is beginning to function is the disappearance of the bilious green color of the gastric aspirate and the decrease in the volume of the aspirate from the nasogastric or gastrostomy tube. Important points to consider

41. Cont. Always start with small volumes of rehydration fluid. If these are tolerated, the feedings are increased gradually until the nutritional goals for the patient have been reached. Infants tolerate increases in volume more than increases in osmolarity. Accordingly, it is often best to start with diluted formulas (three- quarter-strength, half-strength, or quarter- strength In infants, whenever possible, oral feedings or oral stimulation should accompany tube feedings.

42. Abdominal Wall Defects The exposure of bowel results in greater insensible loss of fluid and heat It is crucial to place children with gastroschisis in a warm environment and to protect the bowel (by the help of a plastic bowel bag). Intravenous access should be established immediately, and resuscitation should be initiated before any surgical intervention I.V. line should be placed in the upper extremities or the neck Surgical cases associated with F,E&N problems

44. Intestinal Obstruction These patients usually present with choking or vomiting They may show signs of severe dehydration with metabolic alkalosis (hypochloremic, hypokalemic ) the maintenance requirements and third- space losses,can be replaced with 5% dextrose in 0.25 normal saline with supplemental potassium chloride at 3 mEq/kg/24 hr. Consider TPN Surgical cases associated with F,E&N problems

45. Diaphragmatic Hernia acute respiratory distress and hemodynamic instability Babies will require immediate resuscitation, correction of acidosis, and, in most cases, endotracheal intubation. Surgical cases associated with F,E&N problems

46. Thank you

47. References Neonatology a Lange clinical manual,3 rd edition,Gomella T. et.al,Appleton& Lange. Neonatology pathophysiology and management of the newborn, 5 th ed,Gordon B.et.al.Lippincott Williams & Wilkins. Arnold G. Coran, M.D., F.A.C.S., Professor, Division of Pediatric Surgery, Department of Surgery, University of Michigan Medical School, Surgeon-in-Chief, Section of Pediatric Surgery Department of Surgery, C. S. Mott Children's Hospital,ACS Surgery. 2000; ©2000 WebMD Inc.