Introduction to IV fluids Flashcards
IV fluids are:
- Isotonic if between
- Hypotonic if
- Hypertonic if
- 240 and 340 mOsm/L
- less than 240
- > 340
Intracellular normal volume?
In osmotic equilibrium in normal circumstances (28L)
What are the types of extraceullualr fluid? 3
- Intravascular
- Intersititual
- Third space or transcellular
Describe each of the following:
- Intravascular
- Intersititual
- Third space or transcellular
- Three examples of transcellular space?
- Intravascular (AKA plasma… fluid contained within the circulatory and lymphatic system (3.5 L)
- Interstitial: Fluid that is found outside the circulatory/lymphatic system that surrounds tissues…aka “tissue space” (10.5 L)
- Third space or transcelluar: spaces where fluid does not normally collect in large amounts…
- CSF,
- joint spaces,
- vitreous humor
What are colloids?
Fluids containing larger molecular weight (>8000) proteins and molecules with plasma oncotic pressures similar to normal plasma proteins. Large molecules that don’t pass through cell membranes.
- When colliods are infused they remain where?
2. What do they do there? 2
When infused,
- they remain in the intravascular compartment and
- expand the intravascular volume and
- they draw fluid from extravascular spaces via their higher oncotic pressure
What colliods are used as volume expanders?
3
- Albumin
- Plasma protein fraction…Plasmanate
- Synthetic colloids…Dextran, Hetastarch
- WHat are crystalloids?
2. This will increase the fluid volume where? 2
- Fluids with molecular weight less than 8000 and low oncotic pressure: Hypotonic, Isotonic, and Hypertonic
Contain small molecules that flow more easily across the cell membranes, allowing for transfer from the bloodstream into the cells and body tissues.
in both the
- interstitial and
- intravascular spaces (Extracellular)
Crystalloids: Describe the following solutions:
1. Hypotonic?
- Isotonic?
- Hypertonic?
- a solution of lower osmotic pressure than blood
- noting or pertaining to a solution containing the same salt concentration as blood
- a solution of higher osmotic pressure than blood
What will a hypotonic crystalloid solution cause fluids in the body to do? (know)***
Which solutions are these? 2 (know)***
Will cause fluids to leave the vasculature for the Interstitial and intracellular spaces
- 0.45% NS (1/2 NS)
- And D5W (after infusing- you metabolize the dextrose super quick and it become hypertonic).
Hypotonic crystalloid solutions lowers the serum osmolality within the 1._______ _____, causing fluid to shift from the 2.__________ space to both the 3._________ and 4.________ spaces.
These solutions will 5._______ cells, although their use may 6._______ _____ within the circulatory system.
- vascular space
- intravascular
- intracellular
- interstitial
- hydrate
- deplete fluid
TYPES OF HYPOTONIC FLUIDS?
4
Hypotonic fluids are used to treat patients with conditions causing intracellular dehydration, when fluid needs to be shifted into the cell , such as: 3
- 0.45% sodium chloride (0.45% NS),
- 0.33% sodium chloride,
- 0.2% sodium chloride, and
- 2.5% dextrose in water
- Hypernatremia
- Diabetic ketoacidosis
- Hyperosmolar hyperglycemic state.
Precautions with hypotonic fluid?
2 general precautions and 4 specific
- Never give hypotonic solutions to patients who are at risk for increased ICP because it may exacerbate cerebral edema
- Don’t use hypotonic solutions in patients with liver disease, trauma, or burns due to the potential for depletion of intravascular fluid volume
- ICP
- liver disease
- trauma
- burns
The decrease in 1._______ ____ _________ can worsen existing hypovolemia and hypotension and cause 2._________ ______?
In older adult patients, 3.________ may be an indicator of a fluid volume deficit.
- What should we instruct pts to tell us, if they feel?
- vascular bed volume
- cardiovascular collapse
- confusion
- Instruct patients to inform you if they feel dizzy or just “don’t feel right.”
- Isotonic crystalloids are what?
- What does it increase?
- ANd what does it not affect?
What are examples of these solutions?
3
- noting or pertaining to a solution containing the same salt concentration as blood
- Increases vascular volume
- Doesn’t result in any significant fluid shifts across cellular or vascular membranes
- 0.9% NS (normal Saline)
- Lactated Ringer’s (LR)
- D5W (before infusion)
- Hypertonic crystalloids are what?
- Where will it draw fluid?
- What are examples of these solutions? 5
- a solution of higher osmotic pressure than blood
- Will draw fluids from the cells and interstitial spaces into the vasculature
- IV Fluids:
- 7.5% NS
- D5 in ½ NS
- Dextrose 5% in NS
- Dextrose 10%
- D50
- What are hypertonic solutions?
Whats osmolarity usually? - The osmotic pressure gradient draws water out of where and into where?
- Because of this they are used as?
- Solution that have a higher tonicity or solute concentration.
- Hypertonic fluids have an osmolarity of 340 mOsm/L or higher - The osmotic pressure gradient draws water out of the intracellular space, increasing extracellular fluid volume,
- so they are used as volume expanders.
Some examples of hypertonic solutions?
2
1- 7.5% sodium chloride (7.5% NS):
2- 5% Dextrose with normal saline (D5NS)
Hypertonic solution Indications:
1- 7.5% sodium chloride (7.5% NS)? 2
2- 5% Dextrose with normal saline (D5NS)? 1
- May be prescribed for patients in critical situations of severe hyponatremia.
- Patients with cerebral edema may benefit from an infusion of hypertonic sodium chloride
- which replaces sodium, chloride and some calories
Precautions with hypertonic fluids:
- Hypertonic sodium chloride solutions should be administered only in what?
- Maintain vigilance when administering hypertonic saline solutions because of their potential for causing what? 2
- On what time line should we be giving this?
- Prescriptions for their use should state what? 4
- Where is it better to store hypertonic sodium chloride solutions?
- high acuity areas with constant nursing surveillance for potential complications .
- intravascular fluid volume overload and pulmonary edema.
- shouldn’t be given for an indefinite period of time.
4.
- the specific hypertonic fluid to be infused
- the total volume to be infused
- infusion rate
- length of time to continue the infusion
- It is better to store hypertonic sodium chloride solutions apart from regular floor stock IV fluids .
Therefore, what category are the following:
- 0.9% NS?
- 0.45% NS?
- D5 0.45% NS?
- D5W?
- LR (RL)?
- iso
- hypo
- hyper
- iso then hypo
- iso
State Volemic Effect of 1 L of the following Fluid on intracellular, intersititial and plasma fluid Compartments:
- D5W?
- NS or LR?
- 7.5% saline?
- 5% albumin?
- WHole blood?
D5W:
Intra- 660 ml
Interst. - 255ml
Plasma - 85ml
NS or LR:
Intra- -100 ml
Interst. - 825 ml
Plasma - 275 ml
7.5% saline:
Intra- -2950 ml
Interst. - 2960 ml
Plasma - 990 ml
5% albumin:
Intra- 0
Interst. - 500 ml
Plasma - 500 ml
Whole blood:
Intra- 0
Interst. - 0
Plasma - 1000ml
We can divide the need for IV fluid therapy into two somewhat simplistic areas. What are they?
- Maintenance Therapy
2. Replacement Therapy
What types of imblaances are replacement therapies used for?
2
- Mechanical imbalances
2. Electrolyte imbalances
WHat are examples of mechanical imbalances?3
- Hypotension due to hemorrhage
- Hypotension due to anesthesia
- Excess fluid loss….due to vomiting/diarrhea/decreased oral intake
Two key concepts to remember about fluid homeostasis
- The kidney is the primary manager of body fluid levels
2. Sodium (Na) is the most osmotically active electrolyte in the body
What two kidney issues can complicate IV fluid treatment?
2
- Underlying renal disease complicates things
2. Poor renal perfusion complicates things
The kidney is the primary manager of body fluid levels: When determining fluid status, it is important to note:
3
(Whats the most important?)
- Urine output***
- Serum Sodium
- Urine osmolality (easiest as urine Na)
What other things are importnat but do not replace urine output, serum sodium and urine osmolality in our decision making? 3
- Edema
- BP
- Orthostatic vitals
Whats the difference between maintenance therapy and fluid resuscitation?
Maintenance therapy: replaces normal ongoing losses
Fluid Resuscitation: corrects any existing water and electrolyte deficits.