Principles Of Fluid And Electrolyte Therapy Flashcards
What are the two main types of fluid
Crystalloids
Colloids
Give some examples of crystalloids
Normal saline
Ringers lactate
Dextrose saline
Badoe’s solution
5% or 10% dextrose
Fluid 5:4:1 (for cholera)
GIRS
Darrow’s solution
Give some examples of colloids
Blood
Plasma
Hemacel
Dextran
Give a difference between a crystalloid and a colloid
Crystalloids are small molecules while colloids are large molecules (collagen)
What are some indications for giving IV fluids
Dehydration
Shock
Intestinal failure
Surgery
Nutritional TPN
Drug administration
What are some complications of Iv fluids
Overload
Embolism
DVT
Immune reactions
Infections
Bleeding (dextran)
How many mls of water can be lost by an average adult through breathing and the skin
1700 mls
What is the net loss of water in the average adult
3400 mls
In certain conditions such as metabolic acidosis, you cannot give ………….. So you give …………..
Ringer’s lactate, Normal saline
In dehydration, water is lost from which compartment
ECF
If dehydration becomes chronic, water is lost from the ………….. compartment as well
ICF
During burns, there is fluid distribution from the …………. to the ……………
Intravascular space to the extravascular space
What are some symptoms of dehydration
Sunken eyes
Dry inelastic skin (decreased skin turgor)
Tachycardia
Tachypnoea
Collapsed veins
Capillary refill time (increased)
Altered sensorium
Reduced urine output
What is the urine output of a person
0.5/1ml/kg
30-50
On going losses are mostly ……… losses
GIT
A person came with a deficit. The doctor decided to calculate the fluid deficit and add it to the maintenance. What is this called
On-going losses
What fluid is contraindicated in a dehydrated patient
5% dextrose
A patient who is hemodynamically stable is given ………. for maintenance
4:2:1/kg/hr
How is hyponateiemua treated
It depends on the type whether it is chronic or acute, hypovolemic, hypervolemic or normovolemic
What kinds of saline could be given for hyponatremia
Isotonic saline
Hypertonic saline
Fluid restriction
Diuresis??
What are some things that fluid provide
Solvent from reactions
pH
Exchange of nutrients
Excretion
Excitability (nerve impulses)
Temperature regulation
Chemical signals
What is the percentage of TBW in men
About 60%
What is the percentage of TBW in women
About 50%
What is the % of ICF per body weight
40% of body weight
2/3 of TBW
What is the % of ECF per body weight
20% of body weight
1/3 of TBW
What is the % of TCF per body weight
1% of body weight
What is the % of TCF in the ECF
5% of the ECF
What is the % of plasma per body weight
4% of body weight
What is the % of plasma in the ECF
20% of the ECF
What is the % of IF per body weight
15% of body weight
What % of IF in found in the ECF
75% of the ECF
What are the three main compartments water shift through
IC
IVF
ISF
Water in interstitial compartment recirculated by lymphatics and eventually back into the intravascular space
True or false
True
Mention one ion found in both the ICF and ECF
Na
K
Mg
What ions are found in the ICF
Na
K
Mg
Phosphorus
Proteins
What ions are found in the ECF
Na
Cl
K
Ca
Mg
HCO3
What is the volume of water lost through the urine in a day in the tropics
1500
What is the volume of water lost through stools by a healthy adult in the tropic region
200
There is no potassium lost through sweat
True or false
True
What is the volume of K lost through urine in a day in the tropics
50
What is the volume of K lost through faeces in a day in the tropics
10
What is the volume of Na lost through urine in a day in the tropics
114
What is the volume of Na lost through sweat in a day in the tropics
10-16
What is the volume of Na lost through faeces in a day in the tropics
10
What fluid and electrolytes should be given to a surgical patient who is not eating and not passing stool
3L of water
130mmol of Na
50mmol of K
100g of Glucose
Where is it obtained from
1 litre Ringers lactate + 2 litres of 5% dextrose +3g KCl/24hrs
1 litre normal saline + 2 litres of 5% dextrose + 3g KCl /24hrs
Badoes solution 3l / 24hrs
Dehydration is a state of negative fluid balance. It strictly means loss of water alone but usually accompanied by Na.
It is characterized by loss of ECF, but ICF may be involved
True or false
True
What are some causes of dehydration
Decreased fluid intake
Increase losses via renal, GIT or insensible losses
Fluid shift (ascites, effusions and capillary leak states such as burns and sepsis)
What are the various forms of dehydration
Acute or chronic
Mild or moderate or severe
Isonatraemic or hypernatraemic or hyponatraemic
Some clinical manifestations of dehydration is related to
Intravascular volume depletion
Physiologic compensation attempts that takes place
For patients who are unstable with ongoing losses (eg peritonitis), IV is given at what rate
A faster rate (with a wide bore cannula)
What are some types of fluid to be given to a dehydrated patient
Ringer’s lactate
Normal saline
Dextrose saline
How is deficit given
1L in 30-45 mins
What are some parameters to assess in a patient with dehydration
BP, RR, pulse
Veins
Sensorium
Oxygen saturation
Urine Output
Temperature
What is the amount of fluid you should give to a hemodynamically stable patient
100: 50: 20ml /kg – in 24 hours or
4:2:1/kg/hr in an hour
What is the equation for flow rate (min)
Flow rate duration(min) = Volume (ml) x drop factor
What are some electrolytes which give us problems
Na
K
Mg
Ca
What is the normal range for sodium
135-145 mmol/l
What are some causes of hyponatremia
Diarrhoea
Vomiting
Peritonitis
Fistulae
Burns
Wounds
Severe hyperglycaemia
Dehydrated patient infused with Na free fluids
What is the range for mild hyponatremia
130-134 mmol/L
What is the range for severe hyponatremia
< 125 mmol/L or (<120mmol/L)
What is the normal range for moderate hypokalemia
125-129 mmol/L (or 120-129 mmol/L)
What are some symptoms of hyponatremia
Nausea
Headache
Lethargy
Seizures
Coma
Underlying disease
How do you treat hyponatremia
You correct the dehydration or shock by replacing the Na deficit
In the treatment of Na deficit, how do you calculate to know the Na deficit
Na deficit = TBW * (Na goal - Na in plasma)
= 0.6 * your weight * (Na goal - Na plasma)
What are some lab investigations to be done in hyponatremia
BUE
Cr
What are some signs in hyponatremia
Shock
Dehydration
In a serious symptomatic hyponatremia, what is the infusion given to the patient
IV infusion of hypertonic saline target increase of 6 mmol/L over 24 hours (not exceeding 12 mmol/L)
For patients with reduced circulating volume, extracellular volume should be restored with what
An IV infusion of 0.9% saline or a balanced crystalloid solution at 0.5 to 1.0 mL/kg per hour
What is hypernatremia
A rise in serum sodium concentration to a value exceeding 145 mmol/L
What is the greatest risk factor for hypernatremia
Age older than 65 years
What are some renal causes of hypernatremia
Loop diuretics
Polyureic phase of ATN
Post obstructive diuresis of kidney
Nephrologist diabetes insipidus
What are some common causes of hypernatremia
Endocrine syndromes
Failure of renal tubular cells to respond to ADH
Increase salt intake or infusion
Water loss
What are some extra renal causes of hypernatremia
Endocrine syndromes
Vomiting
Diarrhoea
NGT suctioning
Sweating
Fever
Infusion of HTS/increased salt intake
What are some symptoms of hypernatremia
Muscle weakness
Lethargy
Restlessness
Insomnia
Coma in severe cases (central pontine myelinolysis)
What are some investigations to be done in hypernatremia
Serum electrolytes (Na+, K+, Ca2+)
BUN
Glucose level
Urine electrolytes (Na+, K+)
Urine and plasma osmolality
Treatment of hypernatremia depends on …………… status
Volume
How do you treat hypervolemic patients with hypernatremia
When using diuretics, tread cautiously
How do you treat non-volemic patients with hypernatremia
Free water replacement with hypotonic fluids
How do you treat hypovolemic patients with hypernatremia
Use isotonic fluid to offset deficit
What are general things to consider in hypernatremia patients
In asymptomatic patients, don’t correct too rapidly (cerebral edema)
Acute (no more than 1-2 mmol/hr)
Chronic (no more than 0.5-1 mmol/hr)
Sodium levels should not be corrected at a rate more than 8 mmol/day
Acute (< 24hours, chronic > or =24 hours)
What is the normal range for potassium in the body
3.5-5.5 mmol/L or 3.6-5.2 mmol/L