Summary NSG 3800 Exam 1 Study Guide

RBC  4.2-6.1


Adult Health II
Exam 1
Unit 1: Fluid and Electrolytes
Fluid Imbalances
The ECF compartment is divided into the intravascular, interstitial, and transcellular fluid spaces:

Intravacular Space:
3 L of the average 6 L of blood volume in adults is made up of plasma
3 L is made up of erythrocytes (RBC), leukocytes, and thrombocytes
Interstitial Space:
 Contains the fluid that surrounds the cell and totals about 11 to 12 L in
an adult
Lymph is an interstitial fluid
Transcellular Fluids:
Smallest division of the ECF compartment and contains approximately
1L
Examples:
oCerebrospinal
oPericardial
oSynovial
oIntraocular
oPleural fluids
oSweat
oDigestive secretions

Movement of Fluids
Cell Membrane
Pumps used to exchange sodium (outside) and potassium (inside)
Capillary Walls
Hydrostatic vs. osmotic pressure
Normal movement of fluids through the capillary wall into the tissues depends on hydrostatic pressure (the
pressure exerted by the fluid on the walls of the blood vessel) at both the arterial and the venous ends of the
vessel and the osmotic pressure exerted by the protein of plasma
The direction of fluid movement depends on the differences in these two opposing forces

,Hypovolemia (FVD)
Patho and Etiology
When loss of ECF volume exceeds the intake of fluid
Water and electrolytes are lost in the same proportion as they exist in normal body fluids
oThe ratio of serum electrolytes to water remains the same
FVD should not be confused with dehydration
oWhich refers to loss of water alone, with increased serum sodium levels
FVD may occur alone or in combination with other imbalances
oUnless other imbalances are present concurrently, serum electrolyte concentrations remain
essentially unchanged
Causes of FVD include vomiting, diarrhea, GI suctioning, sweating, etc.
 Oral intake is controlled by the thirst center in the hypothalamus

Signs and Symptoms
SUDDEN Weight loss (acute) Flattened neck veins
Decreased skin turgor Muscle cramps
Oliguria Cool, clammy skin
Decreased BP/increased pulse & temp Lethargy

Diagnosis
Hemoglobin & Hematocrit
Increased d/t decreased plasma volume
Conditions that increase the hematocrit value  dehydration and polycythemia (a lot of RBC’s)
Conditions that decrease hematocrits  overhydration anemia
BUN & Creatinine (kidney function)
BUN elevated out of proportion of the serum creatinine Hgb 
Urine Specific Gravity
Increased in relation to the kidneys’ attempt to conserve water Hct 
More concentrated BUN 
Potassium & Sodium 10-20
 Reduced (hypokalemia, hyponatremia) or elevated (hyperkalemia, hypernatremia) Creatinine
Hypokalemia  GI and renal losses
Hyponatremia  increased thirst and ADH release  0.5-1.2
H&P Sodium
Medical Management
***Replace fluid needs
PO preferred
oIs the patient nauseous or have mouth pain?
oOrder for antiemetics
oFluids with glucose and electrolytes
Rehydrate, Elete, Cytomax
oTube feeding (enteral fluids) considered with water flushes
IV route – if severe loss to expand plasma volume – PRIORITY
oIsotonic electrolytes solutions
LR & 0.9% sodium chloride (NS)  expand plasma volume
oOnce normotensive  HYPOTONIC (1/2 NS)




Nursing Interventions

,I/O  OUTPUT  0.5 mL/kg/hr or 30 mL/hour
Daily weight
LOC
oMore volume = more perfusion
oThey should have better perfusion to the brain
Breath sounds
oWe want to ensure we don’t overhydrate
oCrackles
Skin color
Mucous membrane
VS q4 hours
oPulse should be coming down
oBP – no more orthostatic hypotension
Administer fluids 
oIsotonic  severe
oNormotensive/stable move to a hypotonic solution (0.45% NaCl)
Monitor urine specific gravity  should start to stabilize (enough volume in and out)
Evaluate plan of care
Monitor for hypothermia (usually accompany each other)
Skin turgor q8 hours

, Hypervolemia
***FVE  isotonic expansion in the ECF
Etiology
Abnormal retention of water and sodium
oSecondary to increase in total body sodium content
oLeads to an increase in total body water
oThe serum sodium remains the same
oAldosterone chronically stimulated
Remember the RAAS
Contributing factors
oHF
oKidney injury
oCirrhosis of the liver
oIncrease intake of sodium or table salt
oIncrease sodium-containing IV fluids

Signs and Symptoms
Acute weight gain
Edema, distended neck veins
Crackles
Increased CVP
Increased BP & RR (dyspnea from pulmonary edema)
Increased urine output

Diagnosis
Hemoglobin & Hematocrit – decreased
oConditions that increase the hematocrit value are dehydration and polycythemia, and those that
decrease hematocrit are overhydration and anemia
BUN – decreased
oD/t plasma dilution, low protein intake, anemia
Creatinine
oKidney disease – osmolality and sodium levels are decreased d/t excessive retention of water
Serum osmolality
Urine sodium and specific gravity (1.005-1.030)
oMeasures the kidney’s ability to excrete or conserve water
oThe larger the volume the urine, the lower the specific gravity
Health history and assessment

Medical Management
***Treat the underlying cause
Discontinue IVF
PO fluid restriction (First shift  most & Second shift  less & Third shift  least)

Pharmacological Therapy:
Loop diuretics: Furosemide (Lasix)
oCan cause a greater loss of both sodium and water because they block sodium reabsorption in the
ascending limb of Henle loop, where 20% to 30% of filtered sodium is normally reabsorbed
oFor SEVERE HYPERVOLEMIA
Thiazide Diuretics (Hydrochlorothiazide)
oThiazide diuretics block sodium reabsorption in the distal tubule, where only 5% to 10% of
filtered sodium is reabsorbed
oFor MILD to MODERATE HYPERVOLEMIA
Dialysis