Fluid Imbalance Flashcards
(111 cards)
B. Extracellular –
outside the cell (2 areas) 1/3 of all body fluids 20% of body weight Circulates between the cells contains water, electrolytes and nutrients
1. Intravascular compartment – inside vessels; plasma 2. Interstitial compartment – between cells and vessels; fluid in and around the tissues
- Third spacing -
shift of fluid from intravascular space into a “third” or extra space.
- body cavity - out of the blood stream and into the interstitial space; such as a pleural effusion or ascites (excess fluid in the space between the tissues lining the abdomen and abdominal organs [the peritoneal cavity], caused by high pressure in the blood vessels of the liver [portal hypertension] and low albumin levels)
- interstitial spaces – edema (such as in ankles); from injury when there is a shift of fluid into the interstitial space – the body can’t use that fluid anymore because it’s not available in the cells
Objective 2 Discuss the Regulation of Fluid Balance in the Body
A. Thirst -
Thirst center in hypothalamus stimulated by:
1. dry mucous membranes in the mouth 2. drop in blood volume – stimulates the body to be thirsty 3. increase in serum osmolality – lab tests show this; an ( sodium level in extracellular fluid
B. Kidneys
Regulate excretion and retention of water and electrolytes
The glomerulus and nephron regulates this
GFR (glomerulus filtration rate) – lab tests that tells how well the kidney is functioning
1500-2600 mL of urine is produced each day
Renin-Angiotensin-Aldosterone System –
RAAS - Works to maintain intravascular fluid / blood balance and blood pressure - 👆thirst, 👆B/P (constricts vessels), and retains water
a mechanism in the body which gets triggered; renin is produced which stimulates angiotensin which clamps down on the vessels (controls the B/P) and the aldosterone gets stimulated which retains fluid.
Renin is produced by the kidneys; it works on the vessels to maintain B/P and the kidneys to maintain volume
Renin will 👆thirst
Renin will 👆B/P (by constricting the blood vessels)
Aldosterone will retain water(it’s a antidiuretic)
D. Antidiuretic Hormone
(ADH) – (antidiuretic = against losing fluid)
- produced in brain (hypothalamus) and stored in pituitary
- ADH’s release is triggered in response to low blood volume (if bleeding out the kidneys are stimulated to keep fluid in and to reabsorb fluid) or 👆serum osmolality. (Triggers for thirst)
Stimulates water reabsorption
FLUID IMBALANCES
Objective 1 Describe the Distribution of Fluids in the Body:
A. Intracellular
- inside the cell
2/3 of all body fluids
40% of body weight
Provide cell with nutrients and assist in cellular metabolism
Atrial Natriuretic Peptide (ANP)
-secreted by cells lining the atria in the heart as a response to overdistention
when atria stretch too far (pt in fluid overload) the ANP is stimulated causing an 👆in urine output (gets rid of extra fluid/ gets rid of sodium and water)
Fluid volume deficit
Dehydration =
Fluid volume deficit that is a decrease in intravascular, interstitial and/or intracellular body fluid
Fluid volume deficit
2. Hypovolemia
= decreased circulating blood volume and isotonic fluid loss from extracellular spaces
Etiology of dehydration:
- excessive fluid loss
- insufficient fluid intake
- fluid shifts – r
- failure of regulatory mechanisms that are supposed to help balance fluid levels
Clinical Manifestations of dehydration – by body system
- neurologic –
altered mental status- irritable, anxious, restless, confusion
- 👇alertness
- coma(severe FVD)
Clinical Manifestations of dehydration – by body system
- mucous membranes
dry, sticky
pale
longitudinal furrow on tongue, cracks
tongue can 👇in size
Clinical Manifestations of dehydration – by body system
3. skin
- turgor will be diminished (no longer brisk) – check under collar bone
- dry skin (but doesn’t apply to elderly who tend to have dry skin anyway)
- pale, cool extremities
- sunken eyeballs
Clinical Manifestations of dehydration – by body system
3. urinary –
Body weight: min urine output 0.5ml/kg body weight/hr (see pg 2 notes)
-👇urine output (oliguria)
-👆urine specific gravity (the concentrated amounts of particles in urine)
Normal SG:1.005-1.030 ⭐️dehydration SG>1.030
Clinical Manifestations of dehydration – by body system
5. cardiovascular
-👇 B/P
-Orthostatic hypotension
-Tachycardia (compensatory mechanism – compensating for ( B/P)
-Flat neck veins (r/t ( venous filling)
-👇pulse volume (won’t feel the normal +2)
-👇capillary refill time (ex. 👆from 3 seconds to 5 or 6 seconds)
-👆hematocrit (can use the hematocrit level to determine if pt is dehydrated or has fluid volume overload)
Hemoglobin : Hematocrit normal ratio is 1:3
-so 12:36 would be normal
-but 12:42 = dehydration
Clinical Manifestations of dehydration – by body system
6. musculoskeletal
- fatigue
- weakness
Clinical Manifestations of dehydration – by body system
7. metabolic processes
- increase or decrease in body temperature (if don’t have the fluid circulating, the body can’t cool off)
- Thirst
- ⭐️Weight loss⭐️- important ( 1kg (2.2lb)= 1L of fluid
Collaborative Management for dehydration
1. Assessment
a. assess all of the above clinical manifestations
b. laboratory assessment – look at lab results
hemoconcentration – 👆Hct: if pt is dehydrated their blood is concentrated because their volume is deficient; the hematocrit is going to look higher; hematocrit is a % of RBC as compared to the total volume of blood
increased osmolality (>300mOsm/Kg) -👆glucose,👆protein, 👆BUN,👆Na
Urine – urine will be concentrated and there will be an 👆specific gravity (> 1.030)
c. vital signs – 🔼B/P, orthostatic hypertension
d. intake and output
e. daily weight (most sensitive ) -1 Kg (2.2#) = 1 liter of fluid
Collaborative Management for dehydration
- Assessment
2. Fluid replacement
Collaborative Management for dehydration
Fluid Replacement
a. Oral rehydration: fluids that contain electrolytes and glucose (Gatorade, Pedialyte)
Medication – treat the underlying cause
- If vomiting, give antiemetic
- If diarrhea, give antidiarrheal
intravenous therapy:⭐️dr. Orders needs to include soln, rate, and additives.
-fluid challenge (fluid bonus)administer a specific amount of fluid over a short period of time to replace fluids; monitor pt closely
- D5W (hypotonic soln) if Na is high – given slowly over 48° to prevent cerebral swelling; the purpose is to put fluid back into the cells, but if done too rapidly the tissue swells causing confusion, etc.
- NS if Na is not elevated – going to use an isotonic soln (mean equal or like what’s in our body, such as normal saline); 0.9% sodium chloride is normal saline; given more rapidly because it doesn’t act like the D5W where it pulls water into the cells and causes swelling; this is given to pts with fluid volume deficit for both fluids and solutes that were lost r/t diarrhea, vomiting
INTRAVENOUS THERAPY
* Dr.’s orders need to include RATE, SOLUTION, and ADDITIVES (such as potassium)
A. Crystalloids -
Solutions with small molecules that flow easily from the bloodstream into cells and tissues
- Isotonic solutions
Ex. 0.9% Sodium Chloride (NS – normal saline) - Hypotonic solutions
Ex. 0.45% Sodium Chloride (1/2 NS) - Hypertonic solutions -
Ex. 5% Dextrose & 0.9% Sodium Chloride (D5 NS)
10% Dextrose in Water (D10W)
INTRAVENOUS THERAPY
⭐️Different types of IV soln⭐️
A. Crystalloids -
1. Isotonic solutions -
Any solution with a solute concentration equal to the osmolarity of normal body fluids
- concentration of so lutes in a solution of osmoles/L
- 0.9% Sodium Chloride (NS)- most common
- Lactated Ringers(LR) – similar to what is in plasma; contains sodium, potassium, calcium, chloride) not a soln ran for long periods of time, ICU pt.
- 5% Dextrose in Water (D5W) – isotonic in bag, but acts as hypotonic in body
- Dr.’s orders need to include RATE, SOLUTION, and ADDITIVES (such as potassium)
INTRAVENOUS THERAPY️⭐️Different types of IV soln⭐️
A. Crystalloids -
2. Hypotonic solutions -
Any solution with a solute concentration less than that of normal body fluids;
-draws water INTO cells from extracellular cells (out of vascular system), causes cells to swell (edema) and vessels to collapse.
Ex. 0.45% Sodium Chloride (1/2 NS) and 5% Dextrose in h2o(most common)
- Dr.’s orders need to include RATE, SOLUTION, and ADDITIVES (such as potassium)