fluid therapy hypernatremia

fluid therapy hypernatremia

1. HypernatremicDehydration in Children
Fluid therapy
Ali DerakhshanMD
Shiraz University of Medical Sciences
Shiraz Nephro-Urology Research Center
Shiraz-Iran

2. HypernatremicDehydration
Introduction
The most dangerous type of dehydration
Acute brain shrinkage
Capillary rupture and hemorrhage
permanent neurological injury
Infants are more vulnerable :
Higher insensible losses
Inability to communicate their need
Inability to access fluids independently
Is classified as :
Mild (146-149 mEq/L)
Moderate (150-169 mEq/L)
Severe (≥170 mEq/L)

3. Symptoms and signs of
hypernatremicdehydration
As in other forms of dehydration but with Doughy skin
Mild Moderate Severe
Vital signs
Pulse Normal Rapid Rapidand weak
BP Normal Normalto slightly low ↓↓orundetectable
Weight loss
Infant <5 % 10 % >15 %
Older child <3 % 6 % >9 %
Mucous memb. Tacky Dry Parched
Skin turgor Slightly decreased Decreased Tenting
Eye appearance Normal tearing Decreased tearing sunken No tears + very
sunken
Capillary refill Normal Delayed (>3 s) Very delayed (>5
s)
Urine output Decreased Minimal Anuric
General Appearance Nl Irritable drowsy
Thirst nl thirsty -----

4. Important points Hypernatremicdehydration
They may have:
Altered mental status, Hyperreflexia
Restlessness , Insomnia, High pitched cry
Lethargy, Seizure, Coma
CNS hemorrhage ,Thrombosis
Acidosis and Hemolysis
Hyperglycemia and Hypocalcemia :
Hyper-osmolality impairs insulin and PTH release
Late referral :
Shift of fluid from intracellular to extracellular space
and relative maintenance of ECF
During treatment: shift of water from ECF to ICF
causes brain edema and convulsion

5. Effect of Osmotic pressure on Cells
Hypertonic
solution
Isotonic
solution
Hypotonic
solution

6. 6
Cell in a
hypertonic
solution

7. Effects of Hypernatremia on the Brain
and Adaptive Responses.

8. Management -
hypernatremicdehydration
•The P
Nashould be reduced by not more than 10 -12
mEq/L/day
•Normal hydration should be achieved over 48-72 hours
•Rapid decrease in the extracellular fluid sodium
concentration may lead to cerebral edema

9. Holliday-Segar Since1957
WEIGHT (kg) FLUIDS
0 -10 100 ml/kg/day
11 –20 1000 ml + 50 ml/kg for each kg above 10
>20 1500 ml + 20 ml/kg for each kg above 20
ml/kg/hr according to 4:2:1(Rule)
For a 60kg:4×10+2×10+1×40=100ml/hr
Maint.Na3mEq/100cc,K2mEq/100cc
In Practice:
DW5%+1/2 NS+20mEq/Lit KCL*or
DW5%+NS+20mEq/lit KCL*
*Newborns and prematuresare not included

10. A 3yr old boy wt15kg,2day after a flu like illness ,diarrhea,highfever &
refusal of feeding, seen in pedER in shock,hiswtwas 12.750kg & serum
Na170mEq/l :After twice each time 250 cc Normal salinehis general
condition improved and BP was acceptable. how to continue his fluid Rx
Total deficit=15-12.750=2.250cc
Free water deficit=0.6*Wt12.750[(170/145)-1]=1.32Lit*
2250-1320=930 isotonic loss* with Na of 154mEq/L=143mEq
Since we have to correct Na at least in 2days
2days maintenance=1250 +1250=2500
MaintNa 3/100cc=37.5+37.5=75mEq
143+75=218mEq
He already has received 500cc NS with a Na of 77mEq
218-77=139 mEqtotal Na need
Total fluid need=2500+2250=4750-500 already received as NS=4250 with 139Na→ 31mEq/lit
For each lit of fluid 32mEq Na,0.18%NS =31mEq/LNaor0.2% NS inDW5% =34mEq Na/lit
Check serum Na 4hrs after starting Rx and then decide about further checking …
Ongoing losses have to be replaced as they occur
*This may overestimate the free water
*losses from ECF and ICF

11. Madias NE formula
We can alsousethe following formula:
Change in Na=infusateNa-serum Na/TBW+ 1
Or
Change in Na=infusateNa +K -serum Na/TBW+ 1
If we add 1 Lit of fluid with specific composition (0.2 Ns in DW,
0.45NS in DW ………… how much serum Na will decrease

12. Suggested treatment of Hypernatremia
According to history and P Exam a blood sample for BUN,Cr,NA,K
First fluid resuscitation with NS if in shock state
20cc/kg NS in20-30min could be repeated*
We can continue treatment with NS until the Lab result is ready
If hypernatremia :total fluid need =1.25-1.5 *maintenance
Start with 0.45%Ns in DW5% and also consider ongoing losses
Check serum Na after 4 hrshaving in mind that only 2mEq/L/4hrs ↓ is
acceptable
We should have to change the rate or composition according to
SNalevel
1
st
few hrsand 1
st
day is critical regarding the monitoring of Rx

13. Hypernatremic dehydration
Replacement of deficit in 48-72hrs
To ↓serum Na not more than 10-12 mEq/L/24hr
(0.5mEq/hr)
Possibility of convulsion during treatment (entry of
water inside brain cell)
If convulsion administer hypertonic saline 3 or 5%
To rise the serum Na by 5 mEq/L
1cc/kg Cl Na3%↑serum Na by 1mEq=5cc/kg
TBW*5

14. Monitoring of treatment
Body weight
Frequent clinical examination
Meticulous review of intake and output charts
Measurement of plasma urea and electrolytes in regular
intervals
To ↓serum Na not more than 10 -12mEq/L in24hr
Check serum Na after 4 hrs&…………… ..
Multiple estimations
Frequent reassessment with appropriate adjustments in
therapy
Attention to ongoing losses and replace them with appropriate fluid

15. Treatment of HypernatremicDehydration in
Different SNaLevels
Na145-157mEq/lit:24h
Na158-170mEq/lit:48h
Na171-183mEq/lit:72h
Na184-196mEq/lit:84h
1.25-1.5*maintenance1/2NS+DW5%+KCl20mEq/lit

16. Summary
InhypernatremicdehydrationfluidresuscitationwithNS
Startwith½NSinDW5%andcontinuewith
frequentmonitoringofserumelectrolytes&clinicalevaluation
YoumaychangeIVfluidaccordingto∆inserumNatoa
higherorlowerNaor↑or↓rateofinfusion
0.5mEq/L/hror(10-12mEq/L/24hr)↓inNaisacceptable
YouhavetoaddKClafterurinationofpt.20mEq/lit

17. THANK YOU