Fluid and Electrolytes - Dr. Satish Deopujari

Solvent Volume Dielectric constant Surface tension Some more

Seizures in pyogenic meningitis………

Had seizure on 2nd day . On Dilantin. 10 months female with meningitis. Second L.P.( 3rd day ) showed improvement Refractory seizure on 6th day

S.I.A.D.H.

Hyponatremia………………………………..

K/C of Thalassemia Admitted for G / E improved Was found to be Hyponatremic on

admission ( 112 ) Correction done twice but Hypon. Cont. Asymptomatic all throughout.

PSEUDO HYPONATREMIA…..

Respiratory failure………………………………..

5 months male with R.A.D. was doing well On extensive nebulization and supportive therapy. Deteriorated on 4 the day , lethargic, look exhausted . Respiratory rate is less now. ABG day 2..pH 7.34.,pO2 80 on FiO2 of 50. CO2 30 ABG day 4..pH 7.23.,pO2 85 on FiO2 of 30. CO2 67

Electrolytes gave the answer…

Status on 4 th day On mannitol Blood sugar 377 mg % Serum sodium 151. BUN 38

= 336

Seizures in falciparum malaria

Osmolality (mOsm/kg) = 2 [mEq/L Na+] + (mg/dL glucose) / 18 + (mg / dL BUN) /2.8

14 months male with RTA Hypo tonic no h/o seizures

ECG : suggestive of Hypokalemia with extra systoles Plasma sodium = 140 Plasma potassium = 1.3 Chloride = 117 Bicarbonate = 10 Ca = 6.3 Arterial pH = 7.26 PCO 2 = 23

What effect would correction of acidosis have on plasma K + ? Would correction of Ca be part of initial management . ?

Correction of acidosis will drive k + into the cellsFurther worsening hypokalemia.Acidosis is not sever and can wait. Hypokalemia first.

Hypocalcaemia protects against hypokalemia Thus treatment of hypokalemia should precedeHypocalcaemia.Correction of hypokalemia may precipitate Tetany , this is a less serious than hypokalemia.

What effect would correction of acidosis

have on plasma K + ?

Would correction of Ca be part of

initial management ?

1. Anions - Negatively charged ions, such as chloride . 2. Cations - Positively charged ions as sodium . 3. Colloid/Colloid solution - Liquid containing suspended substances that do not settle out of the liquid/solution 4. Crystalloid - a substance that in solution can pass through a semi permeable membrane and be crystallized. 5. Electrolytes - cations or anions which have the ability to conduct electrical current in solutions.

AgeTBW as % of body weight

ECF as % of body weight

ICF as % body weight

Premature 75-80

Newborn 70-75 50 35

1 Year Old 65 25 40-45

Adolescent Male

60 20 40-45

Adolescent Female

55 18 40

MAINTENANCE REQUIRMENT……

Up to 10 Kg 100 ml/Kg

10 to 20 Kg 1000 ml + 50 ml / Kg above 10.

20 Kg onwards 1500 ml + 25 ml / Kg above 20.

3 mEq Na and K per 100 ml of water

Usually estimated from body weight insensible water loss averages 50 ml per 100 kcal consumed. Provision of 50 ml of water per 100 kcal consumed allows the excretion of isotonic urine. Thus, 100 ml of water is required for each 100 kcal consumed. Empirically, 1-3 mEq Na+ and K+ are required for each 100 kcal . Five percent dextrose is necessary to prevent protein and lipid catabolism. Maintenance requirements are best replaced with [5% dextrose, 0.2% NaCl + 20 mEq KCl/liter].

Maintenance requirements

RESUSCITATION MAINTENANCE

Crystalloid

Replace acute loss

1. Replace normal loss (IWL + urine+ faecal)2. Nutrition support

ELECTROLYTES

FLUID THERAPY

Colloid NUTRITION

Percent Dehydration

Infant

Child

Clinical Signs and Symptoms

Mild 5%3-4%

Increased thirst, tears present, mucous membranes moist, ext. jugular visible when supine, capillary refill > 2 seconds centrally, urine specific gravity > 1.020

Moderate 10%6-8%

Tacky to dry mucous membranes, decreased tears, pulse rate may be elevated somewhat, fontanels may be sunken,oliguria, capillary refill time between 2 and 4 seconds, decreased skin turgor

Severe 15% 10%Tears absent, mucous membranes dry, eyes sunken, tachycardia, slow capillary refill, poor skin turgor, cool extremities, orthostatic to shocky, apathy, somnolence

Shock>15%

>10%

Physiologic decompensation: insufficient perfusion to meet end-organ demand, poor oxygen delivery, decreased blood pressure.

RESTORATION

OF CIRCULATING

VOLUME IS THE

TOP PRIORITY

FLUID IS ……..

NORMAL SALINE

I .C .F BLOOD

K = 140Osm = 280

Na = 140Osm = 280

I .C .F In. S F

K = 140Osm = 280

Na = 140Osm = 280

BLOOD

In. S F

E.C.F. E.C.F.I.C.F. I.C.F.

DEHYDRATION

I S O

HYPERHYPO

120 140 160

240 280 320

W W

ICF ICF ICF

Isonatremic dehydration….

Correction over 24 hours…

20 Kg child10 % Dehy.Na = 140

Maintenance Replacement Total

½ N.S. X X

2000 ml10 % of 20 Kg

1500 ml 3500 ml 5 % dext.

H20

Na3 mEq / 100 ml.15 3 = 45 10 20 = 200 mEq

245 mEq / 3.5 Lt.Loss = 10mEq / Kg

Hyponatremic dehydration….

Slow correction , over 48 hours…Not more than 10 mEq in 24 hours

20Kg child10 % Dehy.Na = 110

Maintenance Replacement Total

( As 5 % dextrose )

1 / 2 N.S. X Na

3 mEq / 100 ml.30 3 = 90

140-110 ½ wt. X

300 mEq

390 / 5 Lit.

2000 ml10 % of 20 Kg1500 2

3000ml5000 ml X H2O

HYPONATRMIC EMERGENCIES

3% hyper tonic saline

5 ml/kg over 1 hour with the goal sodium level of 125meq/ L , then correct sodium further by calculating deficit

Maintenance Replacement Total

1/4 N.S.

Hypertonic dehydration….Slow correction , over 48 hoursNot more than 10 mEq in 24 hours

20 Kg child10 % Dehy.Na = 165

400 m.l. of N.S. = 61 mEq

Free water deficit = ( 4 X wt inKg ) X ( Serum Na – 145)

1500 2 3000ml

3 mEq / 100 ml.30 3 = 90X

X Deficit = 2000F.W.D. = 1600Reminder as N.S.

5000 ml

151 mEq / 5 lit.

H20

Na

HYPER

160

320

W

ICF

HYPERCHRONIC

160

320

W

ICF

RAPIDTREAT.

130

290

W

ICF

Seizure while treating hypernatremia

D 5 % with ½ Normal Saline = 77 mEq Na / Lit.

Add 150ml of 3 % Normal Saline to a Liter of 5 % Dextrose

D 5 % with ¼ Normal Saline = 34 mEq Na / Lit.

Add 70 ml of 3 % Normal Saline to a Liter of 5 % Dextrose

Isonatremic dehydration is best replaced with

5% dextrose, ½ NaCl + 20 mEq KCl/L over 24 hours. ( Deduct bolus therapy )

Hyponatremic dehydration is best replaced

with 5% dextrose ½ NaCl + 20 mEq KCl/L over 48 hours. ( Deduct bolus therapy )

Hypernatremic dehydration is best replaced

with 5% dextrose with ¼ NaCl + 20 mEq KCl/L over 48 hours. ( Deduct bolus therapy )

Fallacies of body fluid calculations

Lean body mass calculations Variation in body secretion Variation in renal handling Effect of body temperature Isohydric effect Variation in surface area

HYPERNATREMIA IN ICU Urine output

Low High

Urine osmolality Urine osmolality

Low HighHigh

Hypo tonic fluidloss

Insensible loss G I Loss Diuretics

D. Insipidus Osmoticdiuresis

Central Nephrogenic

Common IV Solutions

Solution Glucose (g/L) Na+ K+ Ca+2 Cl- Lactate PO4

-3 Mg+2

5% Dextrose (D5W) 50 0 0 0 0 0 0 0

10% Dextrose (D10W) 100 0 0 0 0 0 0 0

Normal Saline (NS) 0 154 0 0 154 0 0 0

D5NS 50 154 0 0 154 0 0 0

D5½NS 50 77 0 0 77 0 0 0

0.2% NS 0 31 0 0 31 0 0 0

3% NaCl 0 513 0 0 513 0 0 0

Ringer's Lactate (LR) 0 130 4 3 109 28 0 0

D5LR 50 130 4 3 109 28 0 0

D10 E#48 100 30 15 0 20 25 3 3

D5 E#48 50 25 20 0 22 23 3 3

D10 E#75 100 57 35 0 40 25 12 6

D6 E#75 60 40 40 0 35 20 15 0

Note: Glucose in g/L; all ions in mEq/L.

98 %

2 %

98 % 2 %

Hyperkalemia

K+

HIONS

K ACIDOSIS CAUSESHYPERKALEMIA

ALKALOSIS ……… LOW K+

True Hyperkalemia

Excess K+ intake

Redistribution

Decreased excretion

Renal failureOliguriaHypoaldo.NsaidsAce inhibitors

AcidosisInsulin Def.Adrenal Ins.Periodic P.

98 % 2 %

K + + + +

Calcium chloride: 0.2 mL /kg/dose of 10% sol IV over 5 min; not to exceed 5 mL (stop infusion if bradycardia develops)Calcium gluconate: 100 mg/kg (1 mL/kg) of 10% sol IV over 5 min; not to exceed 10 mL (stop infusion if bradycardia develops)

Soda bi carb …

2 ml / kg 25 % dextrose with .1 units /kg insulin .over 30 minutes (1 U regular insulin/5 g glucose )

Beta agonists

Hyperkalemia

Hypokalemia…

Hypokalemia true Distribution

Increased loss Urinary K + Decreased

Hypertension Normal B.P.

Acidosis Alkalosis

Renin

G.I.lossBiliary ETC.

I . V . Kesol should be considered for Significant arrhythmia Sever muscle weakness Severe hypokalemia (< 2.5.0 mEq. / L). Digoxin toxicity Hepatic encephalopathy Maximum concentrations of KCl used in peripheral veins generally should not exceed 4 meq. /100 cc, due to the damaging effects on the veins , at a rate of 1 mEq/kg per hour.

Potassium should be administered slowly,

preferably Orally, at a dosage of 4 to 6 mEq/kg per day.

ADH excess

Water retention E.C.Fluid ++

Serum Nalow

Urinary sodiumincreased

Hypotonic Hyponatremia (Na < 135 meq. /L)

Hypovolemia Euvolemia Hypervolemia

Urinarysodium

More than 20 Urinary loss Less than 20 G I Loss Diuretics

SIADH Adrenal Drugs HypoTH

More than 20 C.C.F. Hepatic F. Less than 20 Renal disease

Urinarysodium

SIADH………………

Definition: AVP excess associated with hyponatremia without edema or hypovolemia. The AVP excess is inappropriate in the face of hypoosmolality.

Clinical manifestations are those of water intoxication and depend on rate more than magnitude of development of hyponatremia.

Commonest cause of euvolemic hyponatremia

HYPONATREMIA HYPO OSMOLAR U. OSM. HIGHER THAN SERUM CONTINUED URINARY Na LOSS NORMAL RENAL FUNCTION & B.P. NO OEDEMA NO ENDOCRINE DISORDER RESPONSE TO WATER REST.

SIADH………………

Management

Restrict fluid

Diuretics

Emergency management

and the other drugs……

SIADH………………

The right solution for correct fluid ………..

Thanks

Dr Deopujari