fluid and electrolytes in new born

1. Management of Fluid and Electrolytes in Newborn Dr VishramBuche Director, NICU Central InDIA’S CHILD hOSPITAL & Research INSTITUTE NAGPUR INDIA

2. Central India’s C H I L D HOSPITAL & Research Institute

3. ADVANCED NEONATAL CARE CENTRE

5. Physiological facts……..1 And …….Renal Function

6. TBW……ECF…..ICF 100 B o d y W a t e r c o n t e n t % 80 Fetus 92% TBW 77% 60 66% 60% 60% 40 ICW 45% ECW N e w- B o r n 42% 20 36% 32% 30% 26% 26% 0 0 3 6 9 // 0 3 6 9 Age in months

7. Why Newborn / preterm babies have large amount of water than older infants ? • Why Preterm babies loose more wt than term babies?

8. Potassium…..Non-oliguric Hyperkalemia….

9. Clinical significance:

10. Fluid losses….

12. 3 Days old ….1kg… Preterm , ≤ 32 wks !!! …….Which would be more IWL OR Urine output ?...... Just try to calculate…………!!!

13. Increased insensible water loss (IWL)

14. Decreased insensible water loss (IWL)… ……………Or Measures to ↓ IWL      

15. Loss of H2O > Na …leads to Dehydration, Hypernitremia, Hyperosmolar state, uremia, Acidosis. Apply measures to reduce IWL Clinical Implications….. Failure to prevent….

16. Physiological facts….2 RENAL Prematurity • Limited capacity to concentrate or dilute urine, neither excrete and conserve Na. • Esp.. Preterm babies limited tubular capacity to reabsorb Na. • Limited capacity to acidify urine • GFR  gestational age

17. Renal Prematurity cont… Limited capacity….. CONCENTRATE and dilute urine Adult Term Preterm Concen. capacity 1500 800 600 Diluting capacity 50 mOsmol/kg

18. Clinical implications…. Risk to develop….. • Hypernitremia (Dehydration) • Hyponitremia (Over-hydration) • Hyperkalemia • Acidosis Failure to concentrate and dilute…..

19. Word of Caution……. Babies < 30-32 wks gestnmay continue to pass large amounts of dilute urine despite dehydration becozof renal immaturity. Hence urine output and specific gravity maybe an unreliable indicator of fluid status in these babies.

20. Suggested Protocol…

21. F/E phases in early neonatal Period……

22. Fluid requirements……Volume…. Increment… 15 -20 ml /kg/day

23. …. • Starting Volume… 60-80-100 ml/kg/day • Increase ………15-20 ml/kg/day… • max 150-160 ml by 6-7th day. 1.Radiant warmer 2.Phototherapy 3. ↑ Body temp. 20 ml /kg /day

24. Thumb rules…. Start….1st day……2.5-3.5 ml / kg / hr Add….0.5 ml to 1ml / kg /day Wkend…..5-6 ml / kg / hr Higher wt, Term …..lower requirement Lower wt, Preterm ….. Higher requirement

26. Lytes…….

27. Electrolytes 10 gms / 100 ml 3 mEq/kg Na 4-5 m Eq/kg <32 wks 2 mEq / 100 ml Glucose GM% 5 gms/100ml 8 7 6 5 4 3 2 1 mEq / 100 ml K+ 0 0.5 0.75 1.0 1.5 1.75 2 .0 2.5 3 Wt in Kg

28. Type…. • Day 1 - 2: 10% dextrose • Day 3 onwards : + Electrolytes Na….3mq/kg/day K ……2mq/kg/day (ensure adequate U/O) (10%D+1/6 N saline) • Ped maintenance solution + 50% D to make up 10% concentration (10:1 proportion) (Na 22.7mEq/L, K 18mEq/L) <32 weeks – More Na.

29. Why Preterm/LBW require more Na than full-term babies ? • Why no ‘lytes in 1st 48 hrs of newborn life ? • Why glucose requirement is higher in Preterm / LBW babies?

30. Baby weight 1.2 kg , fluid requirement ? would it be same ? Ask yourself ? What is the gestational age ?

31. Guidelines for Initiating and Adjusting Fluid and Electrolyte Therapy in Newborns Lorenz JM. Fluid and electrolyte therapy in the newborn infant. In: Burg FD, Polin RA, Ingelfinger JR, Gershon A, eds.Current Pediatric Therapy 17. Philadelphia, Pa: WB Saunders; 2002.

32. Fluid required = IWL + UOP + Growth req + stool loss – endogeous water produced – postnatal loss • How these figures of volumes are calculated? • Why preterm / LBW require more fluids than full-term babies?

34. To keep in mind…………… 100 ML/ hr (Ped IV set) 100 Micro-drops/min ml / hr = drops/ min

35. Specific situations…..

36. Special situations…. NO COOK-BOOK APPROACH

37. Monitoring Fluid therapy of the neonates

38. ↑ Osmolality + ↑ Na ↓ Osmolality + ↓ Na

39. Of limited value……..

40. Goals of fluid therapy…. • Urine output 1-3 ml/kg/hour • Urine specific gravity 1005-1015 • (urine osmolality 100-400) • Daily weight loss 1-3% of body weight • Plasma osmolality… 270-285mOsmol/kg • Absence of edema or dehydration • Maintenance of euglycemia(75-100 mg/dl), Normonatremia(serum Na+ 135-145 meq/l) Normokalemia(serum K+ 4-5 meq/ l)

41. Based on above principles…..

43. Na+ K+ Ca+ Hypo <130 (Critical<125) Hyper >150 Hypo < 3.5 (critical < 3) Hyper> 6 ↓Total<7 i < 4 ↑Total > 11 i > 5 Electrolytes Problems…..

44. HyperNa+ …….. IWL… More in Preterm  Na

45.  Na

46. Na interpretation….in clinical context • Is the baby dehydrated ? • Are there ongoing losses ? • Is UOP ed ? • Is the specific gravity  ed ? • Any medications vth  con of Na

47. HypoNa…. • Prematurity….renal Na Loss from ↑FEN • Inadequate Na intake…?hypotonic IV • Excessive water intake…mother IV..5%D • Diuretics..Lasix • ATN (tubular Na loss)….renal Failure • SIADH • Excess Na loss…Diarrhoea • ? Indomethacin

48. Acute symptomatic HypoNa…. • 1 ml/kg of 3% NaCl (0.5 meq/ml)….. …. ↑ Na 1.5 mEq/l Dose… 4ml/kg over 2-3 min Or • NAHCO3 …… 1ml/kg…..↑Na ..3mEq/l 2 ml/kg over 2-3 min

49. HyperK+alemia…… K

50. HyperK+alemia…… Def & ∆… K > 6 (unhaemolysed sample) pH affects K+ …… 0.1 pH change…0.3-0.6 K+ change (▲acid…more K; ▼ acid…less K) K Aetiology…… Oliguric Renal failure, Non-oligurichyperK….▲by dehydrn. Sick cell syndrome 20 Hypoxia CAH, IVH In general K++ ….well tolerated by neonates