Fluid And Electrolyte Balance Flashcards
Intracellular fluid
- Is 2/3 of total body fluid.
- essential for cell metabolism
- Primary cations in ICF are potassium and magnesium
- primary anions are phosphate and sulfate
Difference between anion and cation
Anion- negative charge
Cation- positive charge
Extracellular fluid
1/3 total body fluid
Transports nutrients to cells
Transports waste to kidneys or other disposal.
Consists of intravascular fluid (in vessels)
And interstitial fluid (between cells and blood vessels)
In GI and lymph systems.
Primary cation- sodium,
Primary anion- bicarbonate and chloride
Diffusion
Movement of fluids and electrolytes from an area of high concentration to low concentration.
Example is the movement of oxygen from alveoli into pulmonary blood vessels.
Filtration
Movement of fluid and electrolytes from areas of high pressure to areas of low pressure based on the mechanism of hydrostatic pressure.
Movement of blood from capillaries into interstitial fluid is an example of hydrostatic pressure.
Main element responsible for ensuring acid-base balance.
Hydrogen
Hydrogen ion concentration
If hydrogen ion concentration is lower than neutral the pH values will be higher than neutron.
Low hydrogen= then pH is alkaline, higher than 7.
High hydrogen= then pH is acid, lower than 7.
Buffer
Anything that either binds (absorbs) or releases hydrogen ions.
Buffers stabilize hydrogen ion concentration by neutralizing strong acids or alkalis(bases).
Normal pH of body fluids
7.35- 7.45
How do lungs maintain acid-base balance?
Normal respiration eliminates carbon dioxide.
Carbon dioxide can contribute to acidosis if it accumulates in the blood as carbonic acid.
How do kidneys maintain acid-base balance?
Kidneys are primary regulator of overall fluid and electrolyte balance in the body.
Kidneys either excrete hydrogen and/or bicarbonate ions in urine or by reabsorbing these ions.
Primary hormones that influence urinary output and fluid balance (2)
Aldosterone and
anti-diuretic hormone (ADH)
ADH plays Important role in fluid reabsorption into the blood.
Sodium (Na+)
Primary cation and extracellular fluid.
Maintains fluid balance.
Sodium aids in muscle contraction and transmission of nerve impulses to the muscles.
Aldosterone
Steroid hormone secreted by the adrenal gland.
Helps to maintain sodium balance and potassium balance
Regulates chloride
Potassium (K+)
Primary cation in intracellular fluid.
Responsible for overall muscle contraction, cardiac muscle contraction in particular and impulse transmission of nerves.
Calcium (Ca2+)
Cation
Most plentiful electrolyte in the body. Important for bone into the formation, muscle contraction and relaxation, impulse conduction in the heart, and clotting of blood.
Magnesium (M2+)
Cation in intracellular fluid.
Helps to regulate the heart, promotes neuromuscular and metabolic functioning, component of bones.
kidneys help regulate magnesium
Chloride (Cl-)
Most plentiful anion in extracellular fluid.
Regulated by kidneys and aldosterone secretion.
Gastric juice in the stomach is composed largely of chloride in the form of hydrochloric acid.
Bicarbonate (HCO2-)
Present in both fluid compartments intra-and extra cellular.
Considered a base or alkaline buffer and aids in regulating acid-base balance.
Not ingested in food but is continually produced by the body through various metabolic processes
Phosphate (HPO4 2-)
Most plentiful intracellular anion. A buffer.
Phosphate is important to the formation of bones and teeth; carbohydrate protein and fat metabolism; neuromuscular activity; acid-base balance and calcium regulation
regulated by kidneys and parathyroid hormone
Normal sodium value
135-146 meq/ l
Potassium lab value range
3.5-5.3 meq/l
Over 7 is dangerous
Calcium lab value range
8.5- 10.5 mg/dL total serum Ca
Magnesium normal lab value range
1.5 -2.5 milliequivalents per liter
Chloride normal lab value range
98-108 meq/L
Bicarbonate normal lab value range
22-26 meq/ L
Arterial blood
Phosphate normal lab value range
0.8- 1.5
How to tell if infant is dehydrated
Anterior fontanelle is depressed.
Hypovolemia
(Fluid volume deficit)
What would test results look like for hypovolemia?
Elevated hematocrit Elevated BUN High sp. gravity of urine: >1.030 Elevated serum sodium and chloride Decreased central venous pressure (CVP) Decreased urine volume <30ml/hr
Signs and symptoms of hypovolemia.
Weakness, low temp, weight loss Dry mucous membranes, confusion and slurring of speech, tachycardia, hypotension, orthostatic hypotension, flat neck veins oliguria
Hypervolemia
(Fluid volume excess)
What do you lab values look like?
Decreased hematocrit
Serum sodium: usually unchanged or decreased
Urine: Low specific gravity <1.010
Increased central venous pressure (CVP)
Signs and symptoms of hypervolemia
Weight gain, pitting Edema in legs or sacrum, lethargy, confusion, Rales dyspneic, hypertension distended neck veins
Pitting edema measurement
1+= 2mm indentation 2+= 4mm 3+= 6mm 4+= 8mm
Ascites
Accumulation of fluid in peritoneal cavity of abdomen.
Usually seen in severe liver disease and low albumin levels.
Can also be caused by cancers of colon, endometrium, pancreas, ovaries, and liver.
Extracellular Fluid shift or third space syndrome
Excess fluid and body between Intravascular and interstitial spaces.
Can be caused by injuries like sprains, burns or abdominal surgery.
Causes of Hyponatremia
“NO NA”
Na+ excretion increased with renal problems, NG suction, hypotonic fluids,
Overload of fluids with CHF, hypotonic solution, renal failure (dilutes sodium)
Na+ intake low or NPO
Antidiuretic hormone over secreted -SIADH (syndrome of inappropriate antidiuretic hormone - retains water and dilutes sodium)
Symptoms of hyponatremia
“SALT LOSS”
Seizures and stupor
Abdominal cramping, Attitude changes(confusion)
Lethargic
Tendon reflexes diminished, Trouble concentrating
Loss of urine, Loss of appetite
Orthostatic hypotension, overactive bowel sounds
Shallow respiration (happens late due to muscle weakness)
Spasms of muscle
Causes of hypernatremia
“HIGH SALT”
Hypercortisolism (Cushing’s), hyperventilation
Increased intake of sodium (oral or IV)
GI tube feeding without adequate water supplement
Hypertonic solutions
Sodium retention, corticosteroids
Aldosterone overproduction (hyperaldosteronism)
Loss of fluids- infection,fever,sweating,diarrhea,diabetes insipidus
Thirst impairment
Symptoms of hypernatremia
“FRIED”
Fever,flushed skin Restless, really agitated Increased fluid retention Edema, extremely confused Decreased urine output
Causes of Hypokalemia
“DITCH” (your body trying to ditch potassium)
Drugs: laxatives, diuretics, corticosteroids
Inadequate consumption of K+ (NPO, anorexia)
Too much water intake - dilutes potassium
Cushing’ syndrome (retains sodium and water but wastes potassium)
Heavy Fluid Loss (NG suction, vomiting, diarrhea, wound drainage, sweating)
Symptoms of hypokalemia
Seven Ls
Lethargy and confusion Low shallow respirations Lethal cardiac dysrythmias Lots of urine Leg cramps Limp muscles Low BP and pulse
Causes of hyperkalemia
The body “CARED” too much about potassium.
Cellular movement of K+ from intra to extracellular (burns,tissue damage,acidosis)
Adrenal insufficiency with Addison’s disease
Renal failure
Excessive potassium intake
Drugs- triamterene, ACE inhibitors, NSAIDS, potassium sparing diuretic like spironolactone,
Symptoms of hyperkalemia
“MURDER”
Muscle weakness
Urine production- little or none- renal failure
Respiratory failure- due to muscle weakness
Decreased cardiac contractility- weak pulse, low BP
Early signs -muscle twitches, cramps. Late signs- profound muscle weakness, flaccid
Rhythm changes
Causes of hypocalcemia
“LOW CALCIUM” Low parathyroid (neck surgery) Oral intake inadequate (npo,alcoholism) Wound drainage (esp GI) Celiac and Crohns- calcium absorbed in GI Acute pancreatitis Low vitamin D CKD- excessive excretion of calcium Increased phosphorus(Ca and P do opposite) Using meds- laxatives, diuretic Mobility issues
Symptoms of hypocalcemia
“CRAMPS” Confusion, anxiety Reflexes hyperactive Arrhythmias- prolonged QT interval Muscle spasms, tetany, seizures Positive Trousseau’s sign (bp cuff) Signs of Chvostek’s (facial nerve)
And- abdominal cramps
Hypercalcemia- causes
Prolonged immobility
Bone malignancy
Hyperparathyroidism
Symptoms of hypercalcemia
“WEAK”
Weakness of muscles (profound)
EKG changes- shortened QT interval, prolonged PR interval
Absent reflexes, Absent mind(disoriented), Abdominal distention from constipation
Kidney stone formation
Causes of Hypomagnesemia
Diarrhea
Nasogastric suction
Alcoholism
Long term diuretic use
S/sx of hypomagnesemia
Confusion Hypersensitive reflexes, Tremors Convulsions Positive Chvostek’s and Trousseau’s signs Depressed deep tendon reflexes dysrhythmias Tachycardia Hypertension
Causes of Hypermagnesemia
Renal failure
Adrenal insufficiency
S/sx hypermagnesemia
Lethargy Depressed deep tendon reflexes Bradycardia Hypotension Cardiac arrest, if severe Bradypnea or resp arrest, if severe weakness or paralysis Nausea vomiting
Respiratory acidosis
Characterized by excessive retention of CO2 related to hypoventilation.
Carbonic acid concentration increases, resulting in increase in hydrogen ions and pH below 7.35.
Respiratory alkalosis
characterized by increased exhalation of CO2 due to hyperventilation.
Carbonic acid concentration decreases, resulting in decrease of hydrogen ions and pH above 7.45.
Metabolic acidosis
Characterized by
a decrease in bicarbonate levels and increase in carbonic acid
and increase in hydrogen ion concentration
and decrease in pH to below 7.35.
Metabolic alkalosis
Characterized by
Increase in serum bicarbonate levels
Resulting in decrease in hydrogen ions
And increase in pH to above 7.45.
Causes for respiratory acidosis.
PH below 7.35.
PaCO2 above 45mm Hg
Serum bicarb greater than 28 meq/L
“DEPRESS” anything that causes resp depression
Drugs-opiates, Diseases of neuromuscular system that causes weakness in resp muscles
Edema (pulmonary)
Pneumonia
Respiratory center of brain damaged
Emboli
Spasms of bronchial tube (asthma)
Sac elasticity- alveolar sacs are damages- emphysema, COPD
S/sx of resp acidosis
Confusion, decreased LOC Headache Seizures Tremors Warm and flushed skin Dysrhythmias or tachycardia Rapid shallow breathing (hypoventilation) Dyspnea on exertion
Causes of resp alkalosis:
PH above 7.45
PaCO2 below 35mm Hg
Bicarb below 28meq/L
“TACHYPNEA”
Temp increase
Aspirin toxicity- leads to hyperventilation
Controlled ventilation-mechanical vent. Hyperventilate
Hyperventilation- depletes carbon dioxide
hYsteria- anxiety causes rapid breathing
Pain- rapid breathing, Pregnancy- change in reps tract, Pneumonia
Neurological injury from head trauma- medulla and pons
Embolism or edema in lungs
Asthma when hyperventilating (asthma could also cause respiratory acidosis)
S/sx resp alkalosis
Pos Chvostek’s/ Trousseau’s sign Numbness, tingling extremities and circumoral, Confusion Seizures Hyperventilation Sob, tightness in chest Orthostatic hypotension Muscle twitching/ tremors Weakness
Metabolic acidosis
PH below 7.35
PaCO2 normal
Bicarb less than 22 meq/L
What are causes?
Any condition that increases acids and decreases bases:
“ACIDOTIC”
Aspirin toxicity- increases acid in body
Carbohydrates not metabolized (turns into lactic acid)
Insufficiency of kidneys- acids increase and hco3 can’t keep up
Diarrhea, Diabetic ketoacidosis
Ostomy drainage- depletes bicarbonate
fisTula
Intake of high fat
Carbonic anhydrase inhibitors- diamox
S/sx of metabolic acidosis
Weakness, lethargy Confusion Headache Dysrhythmias Very deep and rapid breathing (KUSSMAUL’s) N/v
Causes of Metabolic alkalosis
pH above 7.45
PaCO2 normal
Bicarb above 26
What are causes?
Any condition the decreases acids and increases bases:
Severe vomiting
Nasogastric suction
Excessive use of diuretics and antacids that cause potassium loss. Low potassium causes reabsorption of HCO3
S/sx of metabolic alkalosis
Irritable, disoriented Numbness tingling extremities Tetany/ muscle twitching Dysrhythmias Decreased, shallow resps N/V/D
Chvostek’s sign
Face is tapped over facial nerve anterior to ear, facial muscles will contract or twitch. This is a positive sign.
Positive if abnormally low levels of serum calcium or magnesium
Trousseau’s sign
Inflate BP cuff on upper arm approx 20mm Hg above their normal systolic pressure. Within 1 to 5 minutes, a carpal spasm may occur. This is a positive sign.
Occurs with low calcium and magnesium.
Central venous pressure (CVP)
Pressure in right atrium of heart or in large veins. Measured with a manometer.
Loop diuretics
Can cause up to 25% of sodium in urine to be excreted.
Act on Loop of Henle.
Major side effect effect- potassium loss.
Patient at risk for metabolic alkalosis.
Furosemide and bumetanide
Thiazide diuretics
Decrease reabsorption of sodium and chloride in distal tubules of kidneys.
Chlorthalazide
Potassium sparing diuretics
Increase excretion of sodium, but not potassium.
Not as much fluid is lost with these diuretics.
Spironolactone
4 basic types of IV solutions
Isotonic
Hypotonic
Hypertonic
Electrolyte solutions
Also volume expanders
Isotonic solution
Most common IV solution.
Help maintain osmotic pressure in extracellular fluid.
Given to patients for hypovolemia, to restore blood volume.
5% dextrose
Normal saline (0.9% NaCl)
Lactated Ringer’s (contains electrolytes)
Hypotonic solutions
Less concentrated than isotonic.
Main action is to provide fluid- water.
Used for basic dehydration.
Half strength normal saline (0.45% NaCl)
One third strength normal saline (0.33% NaCl)
Hypertonic solutions
Used for fluid volume deficits.
Fluid is drawn out of interstitial compartments and into vascular system with these solutions.
5% dextrose in normal saline (D5NS)
Or D5 1/2NS
5% dextrose in Lactated Ringer’s (D5LR)
Percentages of saline can vary.
Electrolyte solutions
Can be isotonic, hypotonic or hypertonic.
Contain sodium chloride and Lactated Ringer’s, which contain calcium, chloride, potassium, sodium and lactate.
The body turns lactate into bicarbonate.
Volume expanders
Fluids are used in extreme trauma like burns where large amts of fluid are lost.
Examples are plasma, albumin, dextran.
Whole blood infusions may be given if H+H are low.
Infiltration of IV
Needle dislodged
Puffiness, pain, feeling of achiness at site.
Skin may be cool to touch.
Treatment: stop infusion, remove needle, apply cold compress initially.
Apply warm compress after 30 min to increase reabsorption from interstitial tissues.
Extravasation of IV
More serious type of infiltration.
Caused bu accidental administration of a vesicant (an IV fluid that can irritate vein walls, trigger vasoconstriction, cause vein to rupture) into extravascular space or tissue.
Pain, infection and severe tissue necrosis may result.
Stop infusion and call MD.
Phlebitis
Inflammation of a vein
Common reaction
Long term IV therapy or piggybacked solutions that are chemically irritating (like potassium)
Edema, warm skin, redness, streaking along vein
D/C IV and warm compress to promote absorption and aid in circulation.
Air embolism symptoms and treatment
Cyanosis, hypotension, tachycardia
Clamp IV tube, turn patient to left side.
Trendelenburg position allows air embolism to gravitate toward feet, right atrium or right ventricle where it becomes trapped rather than becoming pulm emboli.
Trendelenburg position
Head of bed low and foot of bed high
Transfusion or hemolytic reaction
Caused by donor and recipient blood not compatible.
What are the symptoms?
Backache chest pain fever shaking chills cyanosis dyspnea headache hypertension tachycardia
Nursing actions to treat transfusion or hemolytic reaction
Stop transfusion notify physician hang normal sailing solution return all tubing blood bags and transfusion records to blood bank. complete incident report
Blood transfusion allergy caused by antigen-antibody reaction. What are the symptoms?
Bronchial wheeze urticaria dyspnea chest pain cardiac arrest
Nursing actions for blood transfusion allergy:
Mild: Slow transfusion, notify physician, give antihistamines as ordered
Severe: stop transfusion, notify physician, perform CPR if needed
hang normal saline,
return all tubing blood bags and transfusion records to blood bank.
complete incident report
Hypervolemia related to to rapid infusion of blood.
What are the symptoms?
And what are nursing actions?
Sx:
Cough
distended neck veins
dyspnea, hypertension, rales, tachycardia
Nursing actions:
Stop or slow transfusion
notify physician
administer oxygen and other medication as ordered -possibly diuretics
Difference between Macrodrip and Microdrip IV
Macrodrip tubing delivers 10 to 20 gtts/mL and is used to infuse large volumes or to infuse fluids quickly.
Microdrip tubing delivers 60 gtts/mL and is used for small or very precise amounts of fluid, as with neonates or pediatric patients.
How to calculate drip rate?
The formula for calculating the IV flow rate (drip rate) is… total volume (in mL) divided by time (in min), multiplied by the drop factor (in gtts/mL), which equals the IV flow rate in gtts/min.
Normal ranges of:
pH:
Partial pressure of oxygen (PaO2):
Partial pressure of carbon dioxide (PaCO2):
Bicarbonate (HCO3):
pH: 7.35-7.45
Partial pressure of oxygen (PaO2): 75 to 100 mmHg
Partial pressure of carbon dioxide (PaCO2): 35-45 mmHg
Bicarbonate (HCO3): 22-26 mEq/L
What is the expected Compensating mechanism in the presence of respiratory acidosis?
Retention of bicarbonate HCO3 by the kidneys.
What type of imbalance would a salicylate overdose cause?
Respiratory alkalosis because of hyperventilation.
Reaction to blood transfusion: after stopping infusion and notifying md, what is the next step?
Urine sample to test for presence of hemoglobin as a result of RBC hemolysis.
Diuretics may be ordered.
A purpose of isotonic solution. And name 2 examples of isotonic solutions.
Expand the body’s fluid volume without causing a fluid shift from on compartment to another.
Normal saline(0.9% sodium chloride)
And Lactated Ringer’s.
How often should IV tubing be changed?
No more often than every 72 hours or whenever tubing is compromised.
Keep a closed sterile system closed.
Normal hco3 bicarbonate levels
22-26
Normal paCO2 levels
35-45
If calcium is low, what other mineral will be elevated?
Phosphorus
Phosphorus and calcium do the opposite of each other
Types of hyponatremia
3
Euvolemic Hyponatremia is where the water in the body increases but the sodium stays the same. The causes include: SIADH (Syndrome of inappropriate antidiuretic hormone secretion) which is due to the increased amount of secretion of antidiuretic hormone. This hormone retains water in the body which dilutes sodium. Other causes: diabetes insipidus, adrenal insufficiency, Addison’s disease etc.
Hypovolemic Hyponatremia is where the patient has lost a lot of fluid and sodium. Causes: vomiting, diarrhea, NG suction, diuretic therapy, burns, sweating
Hypervolemic Hyponatremia is where the body has increased in fluid and sodium. However, sodium decreases due to dilution and because total body water and sodium are regulated independently in the body. Causes: congestive heart failure, kidney failure, IV infusion of saline, liver failure etc.
S/ Sx diabetic ketoacidosis
Dry and sticky mucous membranes, flushed and dry skin thirst elevated body temperature (even over 102) irritability convulsions Coma
Normal urine output for adult
0.5ml/kg/hour
So a 150 pound person would have approx 35ml per hour.
Daily=840
What type of acid base imbalance would be expected from starvation?
Metabolic acidosis.
The body begins to metabolize its own proteins into ketones which are metabolic acids
Equation for drip rate
Total infusion volume X drops per minute
Divided by total infusion time in minutes
Which cation is the chief regulator of cellular enzyme activity and cellular water content?
Potassium
Which cation assists in the regulation of acid base balance by cellular exchange with hydrogen?
Potassium
Which cation is important for the metabolism of carbohydrates and proteins?
Magnesium
Which cation is necessary for protein and DNA synthesis transcription and translation of RNA?
Magnesium
Which anion acts with sodium to maintain the osmotic pressure of the blood?
Chloride
Which anion is important for cell division and for the transmission of hereditary traits?
Phosphate
