Types of IV fluid, fluid balance

Question 1

3 main types of IVF and how do they differ?

Answer 1

• Isotonic fluids
• Hypotonic fluids
• Hypertonic Fluids
Differ in their influence on fluid shifts between vasculature, cells, and interstitial space. We CANNOT measure osmolality of cells/tissues because it would require taking out cells and looking at them so instead we draw blood then make educated inference

Question 2

isotonic fluids and tonicity/shifts/risks?

Answer 2

volume expander. Expands vasculature with volume: doesn’t cause ANY fluid shifts.
EVENTUALLY if you force enough in there, then there are other forces moving stuff in/out. but just tonicity itself doesn’t do anything to anything other than just vessels.
• Osmolarity similar to serum.
• Fluids remain IVS, expand volume.
• Risk of fluid overloading exists: caution w/Left ventricular dysfunction, history of CHF, HTN

Question 3

isotonic fluid indications

Answer 3

hypotensive, hypovolemic pts

Question 4

isotonic fluid contraindications

Answer 4

•Avoid volume hyper-expansion in pt with intracranial pathology or space occupying lesions.

Question 5

hypotonic indication, fluid shift, example of hypotonic fluid?

Answer 5

give for cellular dehydration.
lower osmolarity than serum: dilutes serum decreasing osmolarity.
•Water moves from the IVS to ISC –> dilutes interstitial fluid –> osmolarity decreases –> water drawn into cells

*Sometimes pharmacy will put something like antibiotic in 1/2 NS (hypotonic) because it would draw antibiotic into the cell. (it’s a little faster)

Question 6

hypotonic fluid cautions

Answer 6

Sudden fluid shifts from IVS

• Cardiovascular collapse
• increased icp in certain patients

Question 7

hypotonic fluid contraindication

Answer 7

hypovolemia, hypotensive in the vasculature because hypotonic fluid will draw it away from bloodstream even more

Question 8

hypertonic fluid indications, shifts

Answer 8

For stabilizing BP, increasing urine output, correcting hypotonic hyponatremia, decreasing edema.

Higher osmolarity than serum, fluid drawn into bloodstream (vasculature).
• Fluid ( & electrolytes) from ICS/ ISC into
IVC.

Question 9

hypertonic fluid shift cautions

Answer 9

•These can be dangerous in the setting of dehydration of cells.
Can be helpful for edema: draws fluid out of the interstitial space also. But also draws fluid from cells, may cause dehydration.

Question 10

cellular vs intravascular dehydration

Answer 10

If pt only has cellular dehydration, not vasculature, BP will be normal. So BP is the “window” for seeing how much fluid is in vasculature.

Question 11

what is more important? cellular or vasculature dehydration? what if pt has both?

Answer 11

What we’re concerned about with dehydration in the vasculature, we are worried about NOT PERFUSING ORGANS causing like acute renal failure. So prioritize dehydrated vasculature over dehydrated cells.

If you have both problems, don’t use hypertonic/hypo cause even if it helps one problem it makes cells worse. Only give isotonic soln if you have both dehydration problems. It’ll bring BP back up, perfuse organs (addressing vasculature first). Eventually, there’s so much fluid in vasculature (not a tonicity change) that itll get pushed out into the interstitial space then into the cells and just by force of excess volume and so it’ll also solve that problem with the cells

Question 12

dehydrated cells s/s

Answer 12

might affect functioning of the tissue little bit

Dry mucous membrane, orthostatic hypotension, poor skin turgor, steady BP

Question 13

dehydration of vasculature

Answer 13

hypotension, cardiac problems, dizziness, flattened neck veins

Question 14

2 main groups of fluids

Answer 14

• Crystalloids: Normal Saline, Lactated Ringers (hypo, hyper, iso, come in big bags). Clear, water/electrolyte solutions, small molecules.
• Colloids: Blood, Blood Products, plasma, plasma fractions, synthetic plasma expanders (synthetic albumin). tend to be hypertonic

Question 15

crystalloids advantages

Answer 15

-Inexpensive
-Easy to store with long shelf life
-Readily available with a very low incidence of ac
reactions
-Variety of formulations that are available that al
for use as replacement fluids or maintenance flu

Question 16

crystalloids disadvantages

Answer 16

takes approx 2-3x more volume of a crystalloid to cause the same IVS expansion as a single volume of colloid.

Question 17

how is albumin a plasma expander?

Answer 17

doesn’t leave vasculature because its too big, takes up space and therefore draws fluid into its area

Question 18

pt gets shot, bleeding a lot, low volume. What’s the tx?

Answer 18

pump them up with clear crystalloids (isotonic) so it can stay in the vasculature. That will bring volume back up. meanwhile, we are cross matching and blood typing cause we wanna give him blood.
We wanna give him blood because blood has more than just small molecules like isotonic soln. Has proteins

Question 19

why is isotonic crystalloid not a good long term soln for dehydrated pt?

Answer 19

eventually theres so much volume, itll push out.

Question 20

colloids

Answer 20

volume expanders.
have a VERY STRONG OSMOTIC FORCE
• Colloids are large molecular weight solutions
-Do NOT readily cross semi-permeable membranes
• High osmolarities
-Important in capillary fluid dynamics
-Causes osmotic force across the wall of the capillaries

Initially stay almost entirely in the IVS for a prolonged period of time compared to crystalloids.

Question 21

colloid indication

Answer 21

• Reducing edema, reduce third spacing, bring up volume

Draw fluid from interstitial and intracellular compartments into the vascular compartments.

Question 22

crystalloids - dextrose solns

Answer 22

Anything wit a D added to it is gonna be hypertonic. (sugar makes you hyper). ONE EXCEPTION: D5W (D 5 weird) - instead of becoming hyper, it is isotonic while sitting on the shelf. But once you start infusing, it starts to act hypotonic.

Ex: 5% Dextrose, dextrose saline

Question 23

5% dextrose

Answer 23

5% Dextrose (often written D5W) — Sugar and water

• To maintain water balance when NPO
• Provides some calories
• Electrolyte free
• Distribution: < 10% Intravascular; >66% intracellular
• Rapidly redistributed into ICS
• Less than 10% stays in IVS

Hardly ever see someone on D5W, more likely D5NS. With dextrose, always check if DM.

Question 24

dextrose saline

Answer 24

2. Dextrose saline — ‘a bit of salt and sugar’ D5NS
   - Similar indications to 5% dextrose
   - Primarily used to replace water losses post operatively
   - Neither really saline or dextrose
   - Advantage: doesnt commonly cause water/salt overload

Question 25

Determining appropriate IVF

Answer 25

1. Assess volume status - What is the volume status of my patient? - Do we want to shift fluid to another compartment? - Can my patient take PO safely? PO fluids preferred. Taking PO same time as iv: get off IV faster. - Is the patient NPO for a reason? - Is the patient diabetic? - What fluids was the patient on previously? Effects of fluids that were stopped recently will still be in their body (if it's already been a day since off it don't worry as much)

Question 26

do we need to know the chart at the end of types of iv fluids ppt?

Answer 26

?

Question 27

what fluid has closest makeup to blood itself?

Answer 27

LR is an isotonic soln that has closest makeup to blood itself.

Question 28

body fluid compartments

Answer 28

- Intracellular Fluids (ICF) - 3/4 total body fluid - Extracellular Fluids (ECF) - 1/4 of ECF is plasma in intravascular space (IVS) - 3/4 of ECF is interstitial in lymph and between cells - supplies food, o2, h20, vitamins, electrolytes, and removes body wastes

Question 29

fluid balance

Answer 29

``` • 2-2.5 liters per day Continually lost -Respiration -Urine -Feces -Perspiration Insensible water loss ```

Question 30

fluid regulation

Answer 30

body is always trying to return to homeostasis. | ex: if person is hypervolemic, inhibit ADH and aldosterone, thirst is inhibited too.

Question 31

effect of aging on fluid regulation

Answer 31

Very common effect of aging: person doesn't have same thirst response as before. They are not thirsty even if dehydrated. Tell them to drink even if don't feel thirsty.

Question 32

osmolality

Answer 32

Osmolality (tonicity but in the body) - Number of molecules of solute per kilogram of water - Isotonic: Blood - Hypertonic: lots of particles, hyperosmolar - Hypotonic: losing particles, hypoosmolar

Question 33

regulation of body fluid mechanisms

Answer 33

Osmosis Diffusion: Simple, facilitated, Active transport Filtration: hydrostatic pressure, osmotic pressure

Question 34

osmosis vs diffusion

Answer 34

movement of water vs movement of particles from areas of less to more solute concentrations

Question 35

filtration influenced by

Answer 35

- Hydrostatic Pressure - Capillary Fluid Movement (Capillary bed is where fluid moves in/out of vacsulature) - Oncotic Pressure - Fluid Shifts (Not because of tonicity in filtration, but because of pressures)

Question 36

hydrostatic pressures

Answer 36

Has everything to do with cardiac function. Pushing pressure. - The major force in the movement of water out of the capillaries into the interstitial fluid - Comes from force of heart pumping. arterial end pressures much higher: that's why it pushes out.

Question 37

hydrostatic pressure and the CHF pt

Answer 37

So patient with CHF with heart that doesn't pump as well as it should, hydrostatic pressure (arterial pressure) may be low since heart is not pumping with enough pressure. That's why we don't give em a lot of fluid.

Question 38

hydrostatic presure vs isc

Answer 38

One factor that determines whether fluid leaves the blood vessels and enters the tissue spaces (interstitial fluid) is the difference between the hydrostatic pressure of capillary blood and that of the interstitial fluid.

Question 39

increased venous hydrostatic pressure?

Answer 39

Stuff's not being properly pushed out ie in CHF, or for some other reason holding onto stuff in vasculature, will bring VP up, so things don't get pushed back in. Increase venous pressure can also be from kidney/liver failure. Movement of fluid blocked by higher vp than normal; edema.

Question 40

oncotic pressure, what is it affected by

Answer 40

Pulling pressure. Drawing from interstitial spaces, so can be done on purpose for pts with edema. Eventually draws from the cells too tho since interstitial spaces draw from the cells •AKA colloidal osmotic pressure caused by colloids in the serum •Colloids are particles that are too large to pass through the capillaries • Edema -Plasma oncotic pressure too low, fluid is not drawn back to capillaries from interstitial space -protein malnutrition

Question 41

liver failure pt and oncotic pressure?

Answer 41

--liver failure patients will have fewer particles in vessels. --> edema. Their BP would actually be low and also their perfusion low because all the fluid is in the interstitial space, not in the vasculature, causing edema, all because they have decreased oncotic pulling pressure d/t decreased colloids. So don't always confuse edema for fluid vasculature overload. Check BP. Decrease the edema and bring up the BP at the same time by giving albumin: volume expander plus is doing it by drawing fluid from ICS, decreasing edema and bringing up BP.

Question 42

what leads to capillary fluid movement?

Answer 42

hydrostatic/oncotic pressures. They are two SEPARATE forces that just happen to be working at the same time. They are not influencing each other. • The amount and direction of fluid movement is based on the hydrostatic pressure and the oncotic pressure -Fluids normally leave to bathe the cells but return to the vessels

Question 43

edema

Answer 43

•Fluid moves from the plasma to the interstitial spaces - when the hydrostatic pressure in the venous vascular system rises, - and/or the colloidal osmotic pressure plasma decreases •Examples - Right-sided heart failure (increased hydrostatic pressure) - Liver failure (decreased oncotic pressure)

Question 44

extreme edema

Answer 44

3rd spacing. Fluid going into spaces that shouldn't have fluid at all. Ascites (liver failure), pleural effusion, burn pts: third spacing all over

Question 45

homeostatic mechanisms

Answer 45

``` Osmoreceptors in hypothalamus • Measure osmolality Dehydration -ADH and Aldosterone - Thirst mechanism Overhydration • ADH, Aldosterone inhibited -if not corrected, can lead to third spacing. thirst mechanism diminished. ```

Question 46

dehydration etiology

Answer 46

``` fluid volume deficit. Etiology • Lack of fluid intake • Excess fluid loss •Regulator alteration -Thirst -hormones -lymphatic system -kidneys ```

Question 47

average daily fluid intake?

Answer 47

1500 to 2500 ml

Question 48

know causes, body compensations, manifestations including labs, management, and pt teaching

Answer 48

5 things yikes

Question 49

EXCESS fluid loss causes

Answer 49

Potential causes of excess fluid loss: • Unmonitored use of diuretics • Severe vomiting and persistent diarrhea • Fever and diaphoresis • Gastrointestinal suction and fistula drainage • Blood loss and burns •Third spacing of fluids (a lot of fluid in the body, but causing vascular dehydration. Not fluid in the right place)

Question 50

how does the body compensate for fluid loss?

Answer 50

• Interstitial fluid moves to restore volume •ADH & aldosterone increase, causing reabsorption of sodium, water • Baroreceptors are stimulated -> vasoconstriction & increased HR • Osmoreceptors signal thirst mechanism •when compensation FAILS, individual experiences fluid volume deficit

Question 51

fluid volume deficit tx

Answer 51

first order: keep fluid in the vasculature, then deal with dehydration of cells

Question 52

effects of fluid volume deficit on osmolarity, cells, fluid

Answer 52

* Hypertonic dehyration: Typically water loss is greater than electrolyte loss (hypertonic loss). Meaning, the blood that's still in the vasculature, is hypertonic. THAT means fluid from the cells and interstitial spaces will be drawn out, resulting in cellular dehydration. BECAUSE number one space to pay attention to is vasculature because of perfusion. * Increases the osmolarity of the remaining plasma, making it hypertonic (aka hyperosmolar) * Increased osmolarity causes water to move from the ICF into the plasma * Results in cellular dehydration and shrinkage * Plasma volume increases to normal or greater than normal levels

Question 53

clinical manifestations of fluid volume deficit

Answer 53

- loss of body weight - changes in intake/output - changes in VS: decreased BP (initially, and particularly orthostatic hypotension), decreased CVP, increased HR to compensate, maybe a rise in temperature because metabolism is going a little faster - dry mucous membranes, decreased skin turgor, headache, dizziness, concentrated urine, decreased urine output, tachypnea - labs basically all go up

Question 54

diagnostic findings in fluid volume deficit

Answer 54

``` Indicators of hemoconcentration •Osmolality above 295 mOsm/kg •Plasma sodium above 145mEq/L •Blood urea nitrogen above 25 mg/dL •Plasma glucose above 120 mg/d •Hematocrit above 55% •Urine specific gravity above 1.030 ```

Question 55

Management for fluid volume deficit

Answer 55

``` • Fluid restoration - Oral or IV rehydration (Oral if you can. Cause gut can take what it wants.) • Thorough Assessment • Monitor for complications • Decreased cardiac output • Dysrhythmias • Electrolyte imbalances • impaired mucous membranes (dryness, cracks) • correct the underlying problem ```

Question 56

pt education: why tell parents they shouldnt give their vomiting/dehydrated child gatorade?

Answer 56

When doing pt teaching, teach parents not to give a vomiting/dehydrated child gatorade because it has a lot of sugar, and if they have too much sugar (like dextrose) it'll just make pt even more dehydrated cause increasing that hyperosmolality. Gatorade is hypertonic. If child RLY wants gatorade, do 1/2 gatorade 1/2 water ESP bad if pt has GI problem: sugar is irritating to gI --> more diarrhea

Question 57

pt education to prevent fluid deficit

Answer 57

• Teach: •Appropriate fluid replacement •Exercise with adequate fluid replacement • Cool water before exercise •150 to 200 ml every 15 minutes exercise •Do not decrease fluid intake for incontinence •drink fluids in absence of thirst

Question 58

fluid volume excess

Answer 58

fluid overload. Hypervolemia • Excess fluids in the vascular system • Third-spacing • Excess fluids in the interstitial spaces (spaces that don't normally have water)

Question 59

fluid volume excess etiology

Answer 59

* Simple overloading of fluids * Failure to excrete fluids * Renal failure * Edema * Heart failure * corticosteroids

Question 60

hypervolemia

Answer 60

When you have too much fluid in the vasculature, it tends to be isotonic. -Isotonic overhydration •Caused by problems that arise from excessive fluid in the vessels •Osmolarity remains normal •Only the vasculature expands and does not shift between the spaces -eventualllyyy hydrostatic pressure increases to the point where it will push fluid into the interstitial spaces *IF pt has a healthy heart because hydrostatic pressure is all about how well the heart is pumping but hypervolemia = too much fluid in BLOODSTREAM

Question 61

third spacing: what is it, causes

Answer 61

* Fluid accumulation in areas that normally have no fluid or a minimal amount of fluids (ascites or edema with burns) * Either from decreased oncotic pressure * Or from hypotonic overhydration (--> edema) * excess fluid is hypotonic to normal body fluids * the osmolarity of the blood decreases and hydrostatic pressure increases * fluid moves into the intracellular space because of the decreased plasma hydrostatic pressure

Question 62

patho: hydro/oncotic pressures during fluid volume excess

Answer 62

Hydrostatic pressure increases, pushing fluids into the interstitial spaces Peripheral vascular resistance increases Pulmonary edema and heart failure develop

Question 63

clinical manifestations of fluid volume excess

Answer 63

``` Respiratory and cardiovascular: -Cough, dyspnea, crackles, pallor, etc. -Bounding pulse, elevated BP, CVP, JVD Other: -peripheral edema -weight gain -confusion, seizure, coma from crossing BBB during things being pushed out from being hypotonic as a LATER effect ```

Question 64

lab indicators of fluid volume excess

Answer 64

``` Indicators of hemodilution •Osmolality less than 275 mOsm/kg •Sodium less than 135 mEq/L •Hematocrit less than 45% •Specific gravity less than 1.010 •BUN less than 8 mg/dL ```

Question 65

management for fluid volume excess

Answer 65

``` • Restrict sodium • Restrict fluids .• Daily weights • Promote urine output • Diuretics and digitalis (if cardiac in nature to increase heart function and ability for hydrostatic pressure to push things out) •Improve myocardial function •Angiotensin-converting enzyme (ACE) inhibitors and beta-blockers • Correct the underlying problem ```