Fluid & Electrolyte balance
Dr M A Maleque Molla;
FRCP(ED), FRCPCH
May 7, 2015
1
Body Composition
 Fluid 60%
 Solid 40 %
Fat
Protein
Carbohydrate
Minerals
2
Distribution of body fluids (by wt)
Intracellular 40%
Fluid 60% of BW
 Itracellular
 Extracellular
(cytoplasm, nucleoplasm)
 Intrstitial
Intrastitial 15%
 Intra vascular(plasma)
(lymph, CSF, synovial fluid, aqueous humor
and vitreous body of eyes, between serous
and visceral membranes, glomerular filtrate of
kidneys. )
Plasma 5%
There is continuous ongoing equilibrium between the intracellular and
extracellular spaces.
3
Fluid content according to age
 Total body water (TBW) vary with age:
 Preterm = 80-85%
 Term = 75%
 Infant= 65%
 Older children & adult male= 60%
 Adult female=50%
• TBW ↓ to 60% by 1st yr of life
• Female has less fluid content because of more fat cells
4
Effective circulating volume (ECV)
Def: Portion of the ECF that take part in tissue
perfusion.
 Only 5% of TBW (intra vascular fluid) are ECV
 Adequate ECF must be maintained all the times
5
Composition of body fluid
 Water
 Electrolytes: Inorganic salts, Sodium(Na),
Potassium(K), Calcium (Ca), Chloride(Cl),
Phosphate(Po4), Bicarbonate(HCO3,
Sulphate(SO4)
 Nonelectrolytes: Minerals -iron and zinc,
Glucose, Lipids, Creatinine, Urea
6
Electrolytes of body fluid
 Electrolytes are measured in mEq or mmol
 Circulating electrolytes electrically charged
 When positively charge called cation: Na+, K+, Ca++
 When negatively charge called anions: Cl- ,HCO3-, SO4-
7
Electrolytes composition of body fluids
Normal Values(serum)
 Cation:
 Sodium (Na+)
 Potassium (K+)
 Calcium (Ca++)
 Ionized Calcium
 Magnesium (Mg++)
 Anion:
 Bicarbonate (HCO-3)
 Chloride (Cl--)
 Phosphate (PO4---)
135 – 145 mEq/L
3.5 – 5.50 mEq/L
8.5 – 10.5 mg/dL
4.5 – 5.5 mg/dL
1.5 – 2.5 mEq/L
24 – 30 mEq/L
95 – 105 mEq/L
2.8 – 4.5 mg/dL
8
CATION
Na+ 140
ANION
Cl- 140
CATION
K+ 140
ANION
Phos- 107
HCO3– 24
Prot- 40
K+ 4
Prot – 14
Ca+ 2.5
Others 6
PO4 - 2
Mg 1.1
EXTRA CELLULAR FLUID
Na+ 13
Mg+ 17
HCO3- 10
Cl- 3
INTRA CELLULAR FLUID
Distribution of Cation and Anion in ECF & ICF (mEq/l)
9
Fluid & Electrolyte balance?
INTAKE
=
OUT PUT
10
Daily physiological fluid balance
INTAKE
 Kidney:
 Skin loss:
 GI:
 Lung
2500 ml/day Total
 Ingested liquid: 1500 ml
 Ingested food: 800 ml
 Metabolism:
200 ml
Total
OUTPUT
1500 ml
600 ml
100 ml
300 ml
2500 ml
Daily fluid balance of an adult
11
Movement of fluid & electrolytes
A. Passive transport (no energy required):
 Osmosis: Fluid move from higher concentration to lower
concentration
 Diffusion = Molecules move from higher concentration
to lower (Concentration gradient)
 Filtration = Fluid and diffusible substances move
together across a membrane; moving from ↑ pressure to
↓ pressure
 Hydrostatic pressure : Fluids moves from an area of
higher pressure to area of lower pressure
B. Active transport( energy required):
 Sodium-Potassium Pump
12
Concentration of Body fluid
 Units of solute concentration are osmolarity and
osmolality
 Osmolarity: Number of osmoles of solute per liter
(L) of solution. It is expressed as osmol/L
e.g 1 mol/L NaCl solution has an osmolarity of 2
osmol/L
 Osmolality : Number of osmoles of solute per
kilogram(kg) of solvent. It is expressed as osmol/kg
 Normal serum osmolality=280-298 mosmol/kg
13
Clinical relevance of osmolality
Calculation
 Serum osmolality (mosmol/kg) =
2(Na+ +K+) mmol/l + Urea (mmol/l)+ Glucose (mmol/l)
 Effective osmolality: Osmotic force that is mediating the
shift of water between the ECF and the ICF =
2 x Na+ (mmol/l )+ Glucose (mmol/l)
 The osmotic gap (osmolal gap): is the difference between the
actual osmolality (measured by the laboratory) and the calculated
osmolality
 A normal osmolal gap is < 10 mOsm/kg
14
Regulation of Body Fluids
Body fluid Homeostasis is maintained through
A. Fluid intake
B. Hormonal regulation
1.
2.
3.
Antidiuretic hormone(ADH)
Renin-Angeotensin-Aldosterone Mechanism
Natriuretic Peptides
C. Fluid output
15
A. Fluid intake
Intake is control by hypothalamic thirst center
•↑ plasma osmolality
of 1–2%
•↓ plasma volume
10%–15%
•Baroreceptor input,
angiotensin II, and
other stimuli
−Ve
•Moistening of the mucosa of
the mouth and throat
•Activation of stomach and
intestinal stretch receptors
16
A. Hormonal regulation
1. Antidiuretic hormone(ADH)
ADH: Secreted by the hypothalamus, and stored in the posterior
pituitary gland
 ADH is released by, thrust, ↓ fluid volume, High serum
osmolality
 Acton:
 Reabsorb water from collecting duct of kidney
 Inhibit sweat glands to ↓ perspiration to conserve water
 Acts on arterioles, causes constriction thus ↑ BP
 ADH is Inhibited by
 Excessive of fluid volume
 Low osmolality of serum
17
2. Renin- Angiotensin-Aldosterone Mechanism
•Low blood volume
•↓Renal perfusion
Aldosterone
Angiotesinogen
Jaxtaglomerular apparatus
Renin
↑ Proximal
renal tubule
Angiotesin I
ACE
↑ Na & Water retention
Systemic
vasoconstriction
Angiotensin II
• Water and salt retention
•↑ effective circulating volume
•↑Renal perfusion
↑ Na & Water
reabsorption
Net effect
•↑ BP
• ↑ ADH
•↑H2O absorption
3. Natriuretic Peptides
 Natriuretic Peptides
 Atrial Natriuretic Peptide(ANP ) from atria
 Brain Natriuretic Peptide(BNP) from ventricle
 Action




Acts like a diuretic that causes sodium loss and
inhibits the thirst mechanism
Inhibit rennin release
Inhibit the secretion of ADH and aldosterone
Vasodilatation
19
C. Regulation by fluid output
Daily fluid losses: 2500 ml for an adult
 Kidney(Urine):
 Skin:
 Lung:
 GI (Stool):
55%
30%
10%
2-5%
20
Renal handling of Fluid & Electrolytes
Substance Filtered
Excreted
Net
reabsorption
98-99%
Water
180 L
1.5 L
Na+
26,000 mmol
100-250 mmol >99%
Cl-
21,000 mmol
100-250
>99%
K+
800 mmol
40-120 mmol
>85-95%
HCO3_
4,800 mmol
0 mmol
100%
Urea
54 gm
27-32 g
40-50%
21
Regulation of Electrolytes
22
Regulation of Sodium & Water
 Major cation in the ECF (N=135 - 145 mEq/L)
 Combines with chloride and bicarbonate to help regulate
acid-base balance
 Recommended daily in take 2.5gm/day
 Kidney regulates sodium balance and is the principal site
of sodium excretion
 Aldosterone helps in sodium and water conservation
23
Potassium regulation
 Major electrolyte and principle cation in the ICF
 Regulates metabolic activities
 Required for glycogen deposits in the liver and skeletal




muscle
 Required for transmission of nerve impulses, normal
cardiac conduction and normal smooth and skeletal
muscle contraction
Daily intake 1-2 mEq/kg
Regulated by dietary intake and renal excretion
Intestine absorbs about 90% of ingested potassium
Regulate by renin-angiotensin-aldosterone mechanism
24
Calcium regulation
 99% of calcium is in the bones and teeth
 1% is in ECF
 50% of calcium in the ECF is bound to protein (albumin)
 40% is free & in ionized form-Ionized calcium
 Ca++ is needed for







Bone and teeth formation
Blood clotting
Hormone secretion
Cell membrane integrity
Cardiac conduction
Transmission of nerve impulses
Muscle contraction
25
Anions
 Chloride (Cl-)
 Major anion in ECF
 Follows sodium
 Bicarbonate (HCO3-)
 Is the major chemical base buffer required for
acid base balance
 Is found in ECF and ICF
 Regulated by kidneys
26
27
Fluid & Electrolyte therapy
28
Fluid therapy
1. Maintenance therapy : Replacement of daily
physiologic losses of water and electrolytes under
normal condition
2. Deficit therapy: Replacement of abnormal
loss
29
Maintenance fluid requirement
 Daily caloric expenditure & water requirement
depends on weight of the children:
 For first 10 kg of wt spend 100 kcal/kg & needs
100 ml/kg of water
 Second 10 kg of wt spend 50 kcal/kg & needs
50ml/kg of water
 >20 kg up to 80 kg, spends 20 kcal/kg needs
20 ml/kg of water
30
Calculation of daily maintenance fluid
Daily Basis*
 Wt 1-10 kg: 100 ml/kg
 Wt 11 to 20 kg: 50 ml/kg
 Wt >20 kg up to 80 kg:20 ml/kg
 Maximum 2400 ml/day.
*Holliday-Segar Method
31
Maintenance fluid requirement
Daily losses in normal condition: 100ml/100kcal
 Sensible losses 60%:


Urine: 55%- 55 ml/100kcal
Stool: 5%- 5 ml/100 kcal
 Insensible losses 40%:


Skin: 30% -30ml/100 kcal
Lung: 10% -10 ml/100 kcal
32
Maintenance fluid requirement (Cont.)
Insensible loss increase:
 Fever-Increase by 10-12% per 1 0C above 37.8 0C
 Tachypnea increase loss by 10-30%
 Prematurity- insensible loss more than term
33
Daily maintenance electrolyte requirement
 Sodium 2 - 3 mmol/100ml H2O /day
 Potassium 1 - 2 mmol/100ml H2O /day
 Chloride 2 - 3 mmol/100ml H2O /day
34
Maintenance therapy
Example: A child is comatosed, not dehydrated. Vital
signs stable. wt 25 kg. outline his fluid management
plan.
Fluid requirement :
First 10 kg:
Second 10 kg:
Rest 5 kg:
Total
10 x 100 = 1000 ml
10 x 50 ml= 500 ml
5 x 20 ml/kg=100 ml
=1600 ml/day.
Electrolytes requirements:
• Sodium =
16 x 3= 48 mmol/day
• Potassium =
16 x 2= 32 mmol/day
• Chloride =
16 x 2= 32 mmol/day
35
What types of IV fluid?
Na+ content
(mEq/L)
Osmolality
(Mosm/L)
Normal saline (0.9% NaCl/L)
154
310
Ringer’s lactate
130
273
One-half NS (0.45% NaCl/L)
77
154
One-third NS (0.33% NaCl/L)
57
114
One-quarter NS (0.25% NaCl/L)
38
76
One fifth NS(0.18% Nacl)
30
60
Dextrose 5%
0
253
Types of fluid
D5 0.45% Nacl
77
405
D5 0.33% Nacl
57
365
D5 0.25% Nacl
38
329
Ringer’s lactate= Na+ 130 mmol/l, K+ 4 mmol/l, Cl-,109 mmol/l, bicarb 28
mmol/l , and Ca++ 3 mg/dl )
36
Q. What type of fluid should be used for the child
of 25 kg for maintenance therapy?
• D5 ¼ th NS with 25-30 meq potassium/day will
adequate
37
38
Fluid Imbalance
 Dehydration
 Hypovolemia
 Hypervolemia
 Water intoxication
39
Dehydration
 Abnormal fluid loss causes fluid deficit called dehydration
 Conditions can leads to dehydration:
 Skin: Fever, under heater, heat exhaustion, burn
 GI: Gastroenteritis, fistula, intestinal obstruction
 Lung: Tachypnea
 Kidney: Polyuria e.g. diabetes
 Miscellaneous: Surgical drain, third spacing
40
Severity of dehydration
According to severity:
 Mild dehydration -3-5% loss of BW
 Moderate dehydration-6-9% loss of BW
 Severe dehydration- ≥ 10% loss of BW
41
Clinical features of dehydration
From Lissauer & Graham 2002
42
Signs & Symptoms
MILD
MODERATE
3-5%
6-9%
General condition*
Well, alert
Irritable
Lethargic/floppy
Thirst*
Thirsty
Drinks eagerly
Unable to drink
Oral mucous*
Slightly dry Dry
Parched
Ant fontanel*
Normal
Depressed+
Depressed ++
Eyes*
Normal
Sunken +
Sunken ++
Skin turgor*
Skin pinch retracts:
Normal
Normally
Depress
in >2 sec
Tenting
Takes>3 sec
Urine output
Normal
Decrease
No urine
Pulse
Normal
Rapid
Rapid & weak
Respiration
Normal
Deep
Deep & Rapid
BP
Normal
Normal
Decrease
Capillary refill time
Normal
± 2 Sec
> 3 sec
Wt Loss
Clinical assessment of severity of dehydration
SEVERE
>10%
43
Types of dehydration
According to serum Sodium (Na) concentration:
 Isonatremic (Isotonic)=
S. Na 135-150 mmol/l
 Hyponatremic (Hypotonic)=
S. Na <135 mmol/l
 Hypernatremic (Hypertonic)=
S. Na>150 mmol/l
44
Management of dehydration
 Fluid therapy
Enteral


Oral rehydration therapy
By NGT
Parenteral
45
Management of dehydration
Oral rehydration therapy (ORT)
Indication:
 Mild & moderate dehydration due to gastroenteritis
Relative Contra indication:
 Shock
 Altered mental status
 Severe dehydration
 Parental limitations
 Excessive vomiting
 Abdominal distention or absent bowel sounds
46
Oral rehydration salt
Preparation of ORS
 ORS supplied in sachet in powder form
or in ready made form.
 One sachet of ORS should be mixed in
1 liter of health water
 Personal hygiene should be maintained
during preparation
 Available as prepared solution e.g.
Pedialyte or Babylyte
47
Composition of ORS
ORS
NaCl NaHco3 sodium citrate
WHO 1975
3.5 g/l
WHO 2002
2.6 g/l
2.5 g/l
2.9 g/l
KCL
Glucose
1.5 g/l
20 g/l
1.5g/l
13.5 g/l
48
Composition of different types of ORS &
other solution
Solution
Glucose
Mmol/l
Na
Mmol/l
Cl
Mmol/l
K
Mmol/l
HCO3
Mmol/l
Osmola
lity
WHO 1975
111
90
80
20
30
310
WHO 2002
75
75
65
20
30
245
Pedialyte
140
45
35
20
30
250
Rehydrate
140
75
65
20
30
310
Cola
700
2
2
0
13
750
Apple juice
690
3
32
0
730
49
Management of dehydration
Fluid calculation
Water deficit= Wt X % of dehydration
 In mild dehydration deficit(5%)= 50 ml/kg
1000 = 50ml/kg)
(1kg=1000gm=1000 ml; 5%= 5 x
100
 In moderate dehydration deficit (6-9%)= 60-90 ml/kg
 In severe dehydration deficit (>10%)=> 100 ml/kg
50
Oral rehydration therapy (ORT)
ORT is divided into 2 phases:
A. Rehydration phase: aims to restore the existing
deficit fluid
B. Maintenance phase: compensate for continued fluid
loss
Golden rule:
“Give them as much as they will drink”
51
Oral rehydration therapy(cont..)
A. Rehydration phase: Replacement of existing deficit
 Deficit is calculated according to severity of
dehydration:
 Mild dehydration – 50 ml/kg
 Moderate dehydration – 70 ml/kg.
 Calculated deficit should be given over 4-6 hour by
small and frequent feed
52
Oral rehydration therapy (cont..)
B. Maintenance phase : Replacement of fluid for
continued loss until diarrhea stops;
 1 mL of ORS should be replace for each gram of
diarrheal stool
 Mild diarrhea (≤ 1 stool every 2 hours): ORS – 100
ml/kg/day until diarrhea stops
 Severe diarrhea (> 1 stool every 2 hours): Need
hospital supervision.
Replace as follows:
 If stool can not be measure- 10 ml/kg/motion
 in severe diarrhea- 10 ml/kg/hour
 If vomiting: replace 2 mL/kg for each episode of
vomiting
53
Management of dehydration
Parenteral therapy
Indications
 Severe dehydration
 Persistent vomiting
 Unable to take orally
 Intestinal surgery
 Paralytic Ileus
54
Parenteral therapy
Shock therapy:
 To be given in severe dehydration.
 Goal is to expand the intravascular fluid volume
rapidly to save the vital organs.
 Isotonic solutions are used e.g. N. saline, ringer
lactate, albumin, plasma:
 Normal Saline– 20 ml/kg IV bolus rapidly over 2030 minute
 Repeat bolus until patient is hemodynamically
stable.
 This phase of therapy is same for all types of
dehydration
55
Parenteral therapy (cont..)
Subsequent therapy:
 Depends upon types of dehydration
 Isotonic & hypotonic dehydration:
 Calculated deficit should be replaced over 24 hours
 Fluid given in initial phase is to be deducted from the
calculated deficit
 Calculate maintenance requirement for 24 hour
 Calculate Na+ & K+ deficit & choose appropriate fluid
 Half of the deficit + maintenance requirement should
be given over 8 hours
 Remaining half to be infused over 16 hours
56
Fluid & electrolyte calculation
Water deficit= Wt X % of dehydration:
 In mild dehydration deficit= 50 ml/kg
 In moderate dehydration deficit = 60-90 ml/kg
 In severe dehydration deficit => 100 ml/kg
Electrolyte deficit:
 Na & Cl deficit=water deficit X 8 mmol/100ml
 Potassium deficit= water deficit X 3 mmol/100 ml
57
Example:
Child wt 10 kg arrived in ER with GE & severe dehydration.
Shock therapy:
 10 × 20=200 ml of normal saline should be given over
20- 30 min as shock therapy
Serum sodium was 138 mmol/l
Subsequent therapy:







Deficit fluid=10×100=1000 ml
Fluid given during shock therapy=200 ml
Remaining fluid deficit= 1000-200=800 ml
Maintenance fluid for 24 hour=10×100=1000 ml
Total fluid for 24 hour = 800 ml+1000ml= 1800 ml
One half of total fluid =900ml to be given over 8 hour
Other half = 900ml to be infused over 16 hour
58
Parenteral therapy(cont..)
Choice of fluid:
 Na requirement:
Deficit fluid 800ml=8 × 8= 64 mmol
Maintenance requirement= 10 × 2=20 mmol
Total = 64+20=84 mmol/day
 Potassium 30+10=40 mmol/day
One half NS in D5W + 20 mmol of KCL/l will be
appropriate solution
59
Parenteral therapy(cont..)
Subsequent therapy:
Hypernatremic dehydration: S Na+ > 160mmol/l
 Initial phase of shock therapy is same
 Deficit therapy should be spread over 36-84 hours
according to the result of serum Na:
 Serum Na 155-170 mmol/l- over 48 hr
 Serum Na 170-183 mmol/l over 72 hr
 Serum Na 184-196 mmol/l over 84 hr
 Goal is to decrease serum sodium 10 mmol/24hr
60
Parenteral therapy(cont..)
Example:
One yr. old wt 10 kg with severe dehydration in shock
 Shock therapy: 20 × 10=200 ml N S to be given over 30
min
U & E’s result shows S. Na 170 mmol/l.
 Subsequent therapy:
Deficit=10 × 100=1000 ml
Fluid given during initial phase= 200 ml
Remaining deficit 1000-200=800 ml
Maintenance requirement for 48 hr=(10 × 100) × 2=2000
ml
 Total fluid 2000+800=2800ml to be given over 48 hr
 NS or ½ NS D5W+ KCL should be use
61
Management of dehydration
Replacement of ongoing losses:
 Can be given parenterally or orally
 Any abnormal losses should be replace ml for ml
 Losses from the previous hours should be calculated
and should be replaced over next same duration
 If stool quantity cannot be measure; 10 ml/kg/ per
motion in previous 8 hours should be replaced over
next 8 hours.
 Losses should be replaced every 1-6 hours depending
on the rate of loss
 NG losses should be replaced 1-4 hourly,
 In diarrhea – fluid should be adjusted 6-8 hourly.
62
63
Hypervolemia
 Excess fluid in the extracellular compartment as a
result of
 fluid or sodium retention,
 excessive intake,
 renal failure
 Occurs when compensatory mechanisms fail to
restore fluid balance
 Leads to CHF and pulmonary edema
64
Signs & Symptoms
 Tachypnea
 Dyspnea
 Crackles
 Rapid, bounding pulse
 Hypertension
 S3 gallop
 Increased CVP, pulmonary artery pressure and
pulmonary artery wedge pressure (Swan-Ganz)
 Acute weight gain
 Edema
65
Management of hypervolemia
 Fluid and Na+ restriction
 Diuretics
 Monitor vital signs
66
Water Intoxication
 Hypotonic extracellular fluid shifts into cells to
attempt to restore balance
 Cells swell up
Causes:
 In appropriately secretion of ADH (SIADH)
 Rapid infusion of hypotonic solution
 Excessive tap water NG irrigation or enemas
 Psychogenic polydipsia
67
Water Intoxication
 May be asymptomatic
 Signs and symptoms of increased intracranial
pressure
 Early: change in LOC, N/V, muscle weakness,
twitching, cramping
 Late: bradycardia, widened pulse pressure, seizures,
coma
68
Management
 Assess neurological status
 Monitor I&O and vital signs
 Fluid restrictions
 Hypertonic saline if S. sodium <120
 Daily weights
 Monitor serum Na+
 Seizure precautions
69
70
Electrolyte Imbalances
 Hyponatremia/ hypernatremia
 Hypokalemia/ Hyperkalemia
 Hypomagnesemia/ Hypermagnesemia
 Hypocalcemia/ Hypercalcemia
 Hypophosphatemia/ Hyperphosphatemia
 Hypochloremia/ Hyperchloremia
71
Hyponatremia
 Serum Na+ level < 135 mEq/L
 Causes:
 Dilutional - results from Na+ loss, water gain
 Depletional - insufficient Na+ intake
 Hypovolemic - Na+ loss is greater than water loss; can be
renal (diuretic use) or non-renal (vomiting)
 Hypervolemic - water gain is greater than Na+ gain;
edema occurs
 Isovolumic - normal Na+ level, too much fluid
72
Signs & Symptoms
 Primarily neurologic symptoms:
 Headache,
 Nausea, vomiting,
 muscle twitching,
 altered mental status, stupor, seizures, coma
 Hypovolemia - poor skin turgor, tachycardia,
decreased BP, orthostatic hypotension
 Hypervolemia - edema, hypertension, weight gain,
bounding tachycardia
73
Management
 MILD CASE
 Restrict fluid intake for hyper/isovolemic
hyponatremia
 IV fluids and/or increased po Na+ intake for
hypovolemic hyponatremia
 SEVERE CASE
 Infuse hypertonic NaCl solution (1.5%,3% or 5%
NaCl)
 Diuretics like Furosemide to remove excess fluid
74
Hypernatremia
 Excess Na+ relative to body water
 Serum sodium >155 mEq/l
 When hypernatremia occurs, fluid shifts
outside the cells
 May be caused by water deficit or overingestion of Na+
 May result from diabetes insipidus
75
Signs & Symptoms
 Flushed skin, agitation, low grade fever, thirst
 Neurological symptoms
 Signs of hypovolemia
 Signs of dehydration is not obvious in
hypernatremic dehydration
76
Management
 Correct underlying disorder
 Gradual fluid replacement over 36-48 hour
in case of hypernatremic dehydration
 Monitor for signs & symptoms of cerebral
edema
 Monitor serum Na+ level
 Seizure precautions
 Replacement of water in case of DI
77
Hyperkalemia
 Serum K+ > 5.5 mEq/L
 Mild: S K+ 5.5-6.5
 Moderate : S K+ 6.5-8.00
 Severe: S K+>8
 Cause
 Altered kidney function,
 Increased intake (salt substitutes),
 Blood transfusions,
 Medication (K+-sparing diuretics),
 Cell death (trauma)
78
Signs & symptoms
 Irritability
 Paresthesia
 Nausea, abdominal cramps, diarrhea
 Muscle weakness (especially legs)
 Arrhythmia
 Hypotension
79
ECG
 ECG changes:
 Prolong PR interval,
 Tal, tented T wave,
 Wide QRS complex,
 Absent P,
 Sine wave
 Asystole
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Management of hyperkalemia
 Treat the underlying cause
 Confirm by repeat analysis, ECG
 Mild hyperkalemia ( S. K+ 6-7mmol/l)
 Dietary restriction
 Loop diuretics (Lasix)
 Moderate hyperkalemia ( S. K+ 7-8 mmol/l)
 Kayexalate (Resoneum)
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Management of hyperkalemia(cont..)
 Severe Hyperkalemia ( S. K+ >8 mmol/l)
 Above management +
 10% calcium gluconate to protect cardiac effects
potassium
 Sodium bicarbonate, β2 agonist to for itracellular
shift of K+.
 Glucose 0.5 gram/kg + Insulin 0.3 units/gm of
glucose infusion
 Dialysis
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Hypokalemia
Serum K+ < 3.5 mEq/L
Can be caused by
 Prolonged diuretic use
 Inadequate potassium intake
 Laxative use
 Diarrhea (including congenital chloride diarrhea)
 Hyperhidrosis
 Hypomagnesaemia
 Renal tubular losses
Acute causes:
 Diabetic ketoacidosis
 Severe GI losses from vomiting and diarrhea
 Dialysis and diuretic therapy
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Signs & Symptoms
 Muscle weakness
 Constipation, ileus
 Irregular, weak pulse
 Orthostatic hypotension
 Numbness (paresthesias)
 ECG changes:
 ST-segment depression
 T-wave flattening
 Appearance of U waves
 Prolongation of QT interval
 Ventricular dysrhythmia,
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Management
 Increase dietary K+
 Oral potassium chloride supplements
 Add K+ replacement if receiving IV fluid
 Change or add K+ sparing diuretic if receiving
diuretic medication
 Monitor EKG changes
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Hypocalcemia
 Corrected Serum calcium < 8.5 mg/dl(<2.1 mmol/L)
 Ionized calcium level < 4.5 mg/dl(1 mmol/l)
 ↓of 1 gm/dl of serum albumin, there is decrease of
0.8mg/dl (0.2 mmol/l) of total serum calcium
 Corrected calcium (mg/dL) = measured total Ca (mg/dL)
+ 0.8 (4.0 - serum albumin [g/dL]), where 4.0 represents
the average albumin level gm/dl
 Cause
 inadequate intake, nutritional ricket
 malabsorption, pancreatitis,
 Hypoparathyroidism (Congenital or aquired),
 loop diuretics,
 low magnesium levels
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Signs & Symptoms
 Neuromuscular
 Anxiety, confusion, irritability, muscle twitching,
paresthesias (mouth, fingers, toes), tetany
 Fractures
 Diarrhea
 EKG changes
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Management
 Calcium gluconate IV for acute symptomatic cases
 Oral or IV calcium replacement
 Vit D replacement in case of Ricket
 Cardiac monitoring
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Hypercalcemia
 Serum calcium > 10.1 mg/dl
 Ionized calcium > 5.1 mg/dl
 Two major causes

Idiopathic

Hyperparathyroidism

Cancer
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Signs & symptoms
 Anorexia, nausea/vomiting, decreased bowel sounds,
constipation
 Fatigue, confusion, lethargy, coma
 Muscle weakness, hyporeflexia
 Bradycardia  cardiac arrest
 Polyuria, renal calculi, renal failure
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Management
 If asymptomatic, treat underlying cause
 Hydrate the patient to encourage diuresis
 Loop diuretics
 Corticosteroids
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Hypophosphatemia
 Serum phosphorus < 2.5 mg/dl
 Can lead to organ system failure
 Cause:
 respiratory alkalosis (hyperventilation),
 insulin release,
 malabsorption,
 diuretics,
 DKA,
 elevated parathyroid hormone levels,
 extensive burns
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Management
 MILD/MODERATE
 Dietary interventions
 Oral supplements
 SEVERE
 IV replacement using potassium phosphate or
sodium phosphate
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Hypophosphatemia
 Serum phosphorus > 4.5 mg/dl
 Caused by
 Renal failure,
 Vitamin D intoxication
 Laxative (Phospho-soda) abuse
 Tumor lysis
 Rhabdomyolysis
 Isolated hypoparathyroidism
 Pseudohypoparathyroidism
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Signs & symptoms
 Cardiac arrythmia
 Hyperreflexia
 poor intake
 Muscle weakness
 Oliguria
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Management
 Treat underlying cause of respiratory acidosis
 Low-phosphorus diet
 Decrease absorption with antacids that bind
phosphorus
 Calcim carbonate
 IV saline for severe hyperphosphatemia in patients
with good kidney function
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