Med surg exam 2 study guide
Chap 11
Fluid compartments
Intracellular 60%
Contained within the cell body
About 25L
Veins, arteries, capillaries, heart, etc
Extracellular 33%
Most important area of homeostasis, area outside of cells
Divided into intravascular space and interstitial space
Extracellular fluid volume is about 15L
In-between the cells
Fluid Balance
Closely linked to/affected by electrolyte concentrations
Fluid intake
2.3-3L a day
Fluid loss
Minimum urine amount needed to excrete toxic waste products= 400-600
mL/day
Insensible water loss-through skin, lungs, stool. Usually 500 to 1L a day
This increases during a fever, tachypnea and extreme stress
Facts to remember
Any fluid imbalances that occur=continuous assessment of UOP
Urine output
Dehydrated pts, CHF, RF, Fluid volume deficient, and fluid volume overload
IV fluids, diuretics
Daily weights
1L of water weighs 2.2lb, equal to 1kg
Weight change of 1lb= fluid volume change of about 500 mL
Fluid volume deficit: Dehydration
Fluid intake/retention does not meet bodys fluid needs; results in fluid volume deficit
Assessment
Thread and increased pulse rate; decreased BP; lethargy; decreased UOP; dry
mucous membranes; constipation; thirst
Increased H&H (hemoconcentration), BUN, sodium, and urine specific gravity
Causes-vomiting, diarrhea, ileostomy, laxatives, burns, fever, diuretics, GI
suctioning, and NPO
Interview/risk factors
Inquire about recent dietary habits
Use of OTC diuretics
Outdoor activities
Weight gain and weight loss
Who at risk: hemorrhage, vomiting, diaherra, excessive sweating, NPO, sustained burn
wounds, GI suction, Diuretics, uncontrolled diabetes, Poor intake
, Flat neck and hand veins, increased RR, skin tenting, tongue wrinkles, dehydration, fever,
UOP concentrated,
Urine specific gravity concentrated (the higher the dryer)
BUN and Creatinine
BUN and Creatinine are kidney markers and are sensitive to decreased blood flow
BUN (10-20) and Creatinine (06-1.2) rise when nitrogenous wastes are found in the
blood indicating kidney impairment
GFR (>65) typically has an inverse relationship (increased BUN and Creatinine with a
decreased GFR)- chronic renal failure
Elevations can be caused by dehydration
Fluid volume overload
Assessment
Bounding and increase pulse; elevated BP; dyspnea, crackles on lung
auscultation; edema; decreased Hematocrit (hemodilution), decreased serum sodium and urine
specific gravity (dilute urine). Weight gain is the best indicator
Causes- ESRD, CHF, water intoxication, SIADH, corticosteroid therapy, and rapid
fluid replacement
Drug therapy
Diuretics (loop diuretics)
Nutrition therapy
Fluid restriction ( 1200 ml/day)
Salt restriction
Monitoring of intake and output
Daily Weight!!!!
ESRD= End stage renal disease
SIADH= syndrome of inappropriate ADH
Edema- while standing ankles, feet, while laying down sacrum, back
Extreme cases it will be everywhere
Electrolyte imbalances: etiology
Hyponatremia
Due to sodium loss, water gain, or inadequate intake
Sodium loss: drugs; diuretics, anticonvulsants, SSRIs, antipsychotics, cancer meds
Hypernatremia
Dehydration, excessive Na intake (sodium polystyrene, sodium bicarb, renal
issue)
Hypokalemia
Not enough in too much out, depleting drugs, medical conditions
Not enough in: inadequate K intake
Too much out: GI fluid losses
Depleting drugs: diuretics, corticosteroids, insulin, excessive laxative use,
albuterol
Black licorice-acts like aldosterone
Hyperkalemia
Too much intake, blood products, drugs, not enough excreted, crush injury
, Too much intake: increased dietary intake,, salt substitutes, potassium
supplements
Donated blood
Drugs: K sparing diuretics, ACE inhibitors, ARBs, NSAIDs
Not enough excreted: renal failure ( low Na, K, protein diet)
Crush injury: intracellular K released
Hypocalcemia
Inadequate intake, malabsorption, calcium loss, others
Inadequate intake: calcium and vitamin D (sunlight)
Malabsorption: post menopausal women, diseases that affect the small bowel,
drugs (anticonvulsants)
Calcium loss: loop diuretics
Others: renal failure, hypoparathyroidism, low magnesium, multiple blood
transfusions, alkalosis, low albumin levels
Hypercalcemia
Increased resorption from the bone
Hyperparathyroidism
Cancer
Thiazide diuretics
Hypomagnesemia
Poor intake, poor GIT absorption, excessive GIT loss, excessive urinary losses
Poor intake; alcoholics, patients on TPN or enteral feeding
Poor absorption: IBD, celiac disease
GIT loss: diarrhea, laxative use, NGT drainage
Urinary loss: diuretics (loop and thiazide)
Hypermagnesemia
Excessive intake, impaired excretion
Excessive intake: magnesium containing antacids/laxatives
Impaired excretion: renal dysfunction
Rare
Sodium imbalances: affect CNS
Hyponatremia
Common: headache, irritability, disorientation/confusion, tired, abdominal
cramping, muscle twitching/weakness, crave salt
Worst case scenario (critical low): psychosis, seizures, ataxia, airway issues
Treatment
Mild: fluid restriction (safest), oral sodium supplements
Critical: hypertonic 3% saline-----SLOWLY!!!
Nursing implications:
Monitor neurologic status, seizure/fall precautions, strict I/Os, implement
fluid restriction, monitor labs
Hypernatremia
Common:
, restlessness or agitation, anorexia, N/V, weakness, lethargy, confusion,
crave water
Worst case scenario:
decreased LOC< seizures, coma
Treatment:
fluids PO/IV, what type (initially isotonic fluid, increase BP, switch then to
hypotonic fluid (D5W) (less salt more water!!!)
Nursing implications
Frequent v/s, monitor neurologic status, seizure/fall precautions, strict
i/os, assess skin/mm, oral care, monitor labs
Give fluids if dehydration present
Potassium imbalances: affect heart/muscles/GI tract
Hypokalemia
Common
Cardiac arrhythmias, leg cramps (hallmark), muscle weakness, decreased
GI motility (decreased BS, constipation, n/v), decreased DTRs, muscle weakness, alkalosis
Worst case scenario
Life threatening cardiac arrhythmias/cardiac arrest
Hypokalemia may potentiate dig toxicity***
Treatment
Increase dietary intake of potassium, k supplementation, Give IV
potassium slowly!!!! 20mEq/hr
Nursing implications
Frequent V/s, cardiac monitoring, patent IV, monitor labs (recheck after
supplementation), NEVER GIVE POTASSIUM IVP OR BOLUS!!!!!
Very dangerous
Remember suction
S= skeletal muscle weakness, U= U WAVE, C= constipation, T= toxic effect of dig,
I= irregular pulse, o= orthostatic hypotension, N=numbness
Hyperkalemia
Common
Cardiac arrhythmias, muscle weakness (which may lead to flaccid
paralysis), increased GI motility, decreased DTR’s, acidosis
Worst case scenario
Life threatening cardiac arrhythmias/ cardiac arrest
Treatment
Potassium restricted diet, if critical/symptomatic will require drug therapy
(CBIGKD) which stand for:
C= calcium, B= bicarb, I= Insulin (regular, IV push), G= glucose, K=
kusulate (sodium poly), D= dialysis
Nursing implications
Cardiac monitoring, frequent labs, VS, monitor for hypoglycemia if insulin
IVP given
Calcium imbalances: affect neurological/neuromuscular system (9-10.5)
