In healthy adults oral fluid intake

Losses of fluids from

insensible

sweat and the vapor in exhaled air

because they are, for practical purposes, unnoticeable and unmeasurable

Number of osmotically active particles per kilogram of water.

A measure of osmotic pull:

*Normal (plasma)= 280-294 Mosm/Kg

*Determined mainly by serum na+

*Increased= Probably dehydrated

*Decreased= Probably fluid overloaded

Osmolality (Mosm/kg), Omolarity (mosm/L) and tonicity often used interchangeably.

Ingested water 1300

Ingested food 1000

Metabolic oxidation 300

Total 2600

Kidneys 1500

Skin -?

Insensible loss 600-900

Sensible loss 0-5000 

Lungs 400

Gastrointestinal 100

Total 2600-2900

% of total body fluid in a:

Premature newborn.

% of total body fluid in a:

Full-term Newborn

% of total body fluid in:

1 year old

% of total body fluid in a:

Puberty to 39 yr old

% of total body fluid in a:

40 to 60 yr old

stretch receptors in the aortic arch and carotid sinus that signal the brain to release ADH when blood volume decreases by 10%, systolic BP falls below 90 mm Hg, or the right atrium is underfilled

also trigger thirst,

% of total body fluid in a:

>60 yr old

are hormone-like substances that act in opposition to the renin-angiotensin-aldosterone system

ANP, BNP, CNP

Removes waste products

Cushions

Protects

Lubricates

Insulates

Provides structures & resilience to skin

produced by the heart's atrial muscle

blocks renin, aldosterone & ADH

results in increased urine and Na output

Sensible fluid loss can be measured.

Insensible fluid loss cannot be measured by ordinary means (computer can calculate).

results when the volume of body fluid is significantly reduced in both extracellular and intracellular compartments.

all fluid compartments have decreased volumes; in hypovolemia, only blood volume is low.

a low volume of extracellular fluid.

Inadequate fluid intake- N/V, insensitivity to thirst, severe mental illness, neuro conditions, anxiety, wired jaw, oral trauma, various surgeries, NPO, poor access to fluids.

Fluid Loss > Fluid Intake- Prolonged or excessive vomiting, diarrhea, hemorrhage, wound, fistula & ostemy drainage, GI suction, burns, profuse urination, perspiration r/t body or environment temp, increased rate/depth of respiration, renal disease, 3rd spacing.

-Thirst, poor turgor, cracked skin and mucous membranes, sunken eyes.

- UO (<25 cc//hr), increased specific gravity, weight loss, orthostatic hypotension.

-Increased HR, weak pulse, increased respirations, decreased BP, decreased CRT, decreased pulse pressure.

-Cold clammy skin if in severe shock.

-Apprehension, restlessness, fatigue, lethargy, decreased LOC, mentation.

Diagnostic tests for fluid volume deficit?

-Increased osmolality

-Increased BUN

-Increased specific gravity

-Serum electrolytes, especially Na, may be increased r/t hemoconcentration

-CBC shows increased HCT r/t hemoconcentration

-Shock

-ATN (acute tubular necrosis)-r/t decreased perfusion

-Increased clotting r/t increased blood viscosity

-Nephrolithiasis: kidney stones r/t waste build up

-Angina r/t decreased CO

Diagnostic Findings

of

hypervolemia

blood cell count and hematocrit level are low as the result of hemodilution, Urine specific gravity is also low,

CVP is elevated above its normal range of 2 to 6 mm Hg.

Movement of fluid into interstitium or body cavity where it becomes trapped and useless to the body (peritoneal, pericardial, pleural, synovial, greater interstitium).

-May be localized or generalized.

Medical Management

of

hypervolemia

-Low albumin

-Increased capillary permeability (trauma, severe allergic reaction)

-Inflammation

Hyponatremia

Causes

profuse diaphoresis, excessive ingestion of plain water or administration of nonelectrolyte IV fluids, profuse diuresis, loss of Gl secretions , and Addison's disease r/t decreased cortisone, hypotonic IV fluids (D5W), excessive Na loss, profuse persipiration, GI loss, diuresis.

-Fluid moves from the intravascular space to the interstitial space.

-Average duration 48-72 hrs

-Results in FVD

Hyponatremia

Manifestations

Reabsorption

-Fluid moves from interstitium space to intravascular space.

-Usually gradually occurs

-May result in FVE if IV fluid is not decreased or if pt has CHF, renal failure, pulmonary disease.

-Same as hypovolemia except pt will GAIN weight

-Enlargement of organ cavities (ascities)

-Anasarca (entire body is edematous)

-Brawny edema (so excessive that fluid cannot be displaced so no pitting, feels hard, skin is shiny and taunt)

Hypernatremia 

Causes

excess sodium in the blood.

Causes include profuse watery diarrhea, excessive salt intake without sufficient water intake, high fever, decreased water intake, excessive administration of solutions that contain sodium, excessive water loss without an accompanying loss of sodium (steriods), renal disease, CHF, increased aldosterone, low water intake and severe burns.

Hypernatremia

S/S

-Fluid intake > fluid output

-Excessive oral intake- mental illness

-Rapid infusion of IV fluids

-Heart failure, renal disease, adrenal disease

-Excessive salt intake

-Steroid drugs

Treatment

Hypernatremia

-Circulatory overload

-HTN, increased force of contractions

-Pitting edema

Hypokalemia

cause

Potassium-wasting diuretics such as furosemide (Lasix), ethacrynic acid (Edecrin), hydrochlorothiazide contribute to this. Decreased dietary intake.  Loss of fluid from the Gl tract. Metabolic alkalosis-> increase in H+ retention so increase in K excreted or shifted into cells.  Large doses of corticosteroids r/t kidneys save Na so you lose K.  IV administration of insulin and glucose, and prolonged administration of nonelectrolyte parenteral fluids

increasing oral intake of potassium-rich foods or using a prescribed potassium oral replacement such as K-Lor,     K-Lyte, or Klorvess.

Severe is treated with IV administration of solutions containing a potassium salt, such as potassium chloride.

Early:

-Weight gain of greater the 1kg/day

-HTN, bounding pulse and decreased pulse pressure

-Diluted urine

-Crackles

-Dependant edema, JVD, puffy eyelids

Decreased activity tolerance, restlessness, fatigue

Late:

-Pitting edema

-Resp distress, increased resp rate, pulmonary edema

-Decreased mentation, anxiety

-Heart failure

-Shock

-Death

Hypokalemia

S/S

fatigue, weakness, anorexia, nausea, vomiting, cardiac dysrhythmias (abnormal heart rate or rhythm, especially in people receiving cardiac glycosides such as digitalis preparations), leg cramps, muscle weakness, and paresthesias (abnormal sensations). May have metabolic alkalosis.

Severe cases result in hypotension, flaccid paralysis, and even death from cardiac or respiratory arrest.

Sodium (Na)

Potassium (K)

Calcium (Ca)

Magnesium (Mg)

Anions found in body fluids?

Chloride (Cl)

Phosphate (HPO4)

Bicarbonate (HCO3)

Sulfate (SO4)

Proteinates

Organic Acids

Main cation in ECF.

Functions:

Regulate fluid volume and distribution

Nerve and muscle activity

Regulate osmotic pressure in ECF

Acid/base balance

Hyperkalemia

Symptoms

Treatment

Hyperkalemia

Mild is treated by decreasing the intake of potassiumrich foods or discontinuing oral potassium replacement until laboratory values are normal.

Severe is treated by intravenously administering a combination of regular insulin and glucose that temporarily shifts serum potassium into cells within 30 minutes of administration

or dialysis

If IV potassium is ordered, it must be diluted in an IV solution and administered at a rate below 10 mEq/hour.

The nurse observes the infusion frequently to verify it is being administered at the appropriate rate.

Major anion of the ECF

Functions:

-Works with Na in maintaining ECF osmotic pressure

-Important in the formation of HCl

-Assists in acid-base balance (moves into cell in exchange for HCO3 to increase pH= chloride shift)

-Sources of Cl= dietary (enters with Na, K and other minerals)

Medications that cause urinary excretion of potassium, such as non-potassium-sparing diuretics 

• Food sources of potassium: vegetables, dried peas and beans, wheat bran, bananas, oranges, orange juice, melon, prune juice, potatoes, and milk 

• Taking oral potassium supplements shortly after meals or with food to avoid Gl distress; effervescent tablets or liquids are taken with a full glass of water

Potassium

and kidney function.

may experience burning along the vein

If the client can not tolerate the fluid, consult with the physician about diluting the potassium in a larger volume of IV solution.

Main cation in ICF

-Increases or decreases in the ECF levels of potassium affect the excitability of cells, and affects the responsiveness to normal stimuli

Functions:

-Nerve and muscle activity (including cardiac)

-Preserve acid/base balance

-Regulates osmotic pressure in ICF

Signs of hypocalcemia

Chvostek's sign

Signs of hypocalcemia

Trousseau's sign

Hypocalcemia

S/S

Treatment

hypocalcemia

hypocalcemia

serum calcium level

if the total serum calcium level is below 8.8 mg/dL (normal range, 9 to 11 mg/dL)

or

the ionized calcium level is below 4.4 mg/dL

(normal range, 4.4 to 5.4 mg/dL).

Hypercalcemia

cause

Hypercalcemia

S/S

Normal concentration of Calcium (Ca) in body fluids?

99% in bones and teeth, 1% dissolved in blood.

Regulated by parathyroids.

Helps in:

-Blood clotting

-Smooth, skeletal and cardiac muscle function

-Nerve impulse transmission

Need vitamin D to absorb from intestines.

Reciprocal relationship with Ph.

Dissolved portion may or maynot be bound to albumin.

Non-bound Ca=ionized Ca (performs functions).

Hypomagnesemia

cause

Some found in bones, 1% in ECF, most intracellular.

Functions closely related to K:

-Affects Na-K pumps

-Direct action on myoneural junction (Nerve impulse transmission & muscle exciteability)

-Catalyst necessary for enzyme reactions (function of vitamin B and use of K & Ca)

-Decreased Mg= Increased cell irritability

-Increased Mg= Decreased cell irritability

Hypomagnesemia

Signs and symptoms

Hypermagnesemia

causes

Hypermagnesemia

Treatment

decreasing oral magnesium intake or discontinuing administration of parenteral replacement. hemodialysis may be necessary.

If respiratory failure occurs, mechanical ventilation is essential.

Governed by the regulation of hydrogen ion concentration in the body fluids.

Measured by pH

-Increased H= acidosis

-Decreased H= alkalosis

Lungs

(Measured by CO2)

1. Chemical buffers- work immediately.

2. Lungs- work within minutes.

3. Kidneys- most efficient, but takes hours to days to work.

(Activation of these systems is termed compensation)

-Provide immediate protection against imbalances by absorbing or releasing H ions.

-Adding H ions increases acidity.

-Removing H ions promotes alkalinity.

-Major chemical regulator of plasma pH is the bicarbonate-carbonic acid buffer system....

Bicarb + H <---> Carbonic Acid <---> water + carbon dioxide

-Regulated by kidneys

-Increase HCO3 in kidneys- increases levels of anions. HPO4 draws H ions, binds with them, and they are excreted in urine as H2PO4.

-"Chloride Shift"

-Cl diffuses in and out of RBC in exchange for bicarb.

-Regulated by level of oxygen in blood

Interacts with chemical buffer system= carbonic acid created by chemical buffer system is broken down into CO2 & H2O and eliminated through the lungs.

H2CO3 <---> H2O + CO2

Ventilation is adjusted according to the CO2 level in the blood.

Increased PCO2 (resp acidosis)= Increased rate and depth of resp (lungs attempt to "blow off" CO2))

Decreased PCO2 (resp alkalosis)= Decreased rate and depth of resp (lungs attempt to retain CO2)

Occurs in tubules.

Affected by concentration of H ions, stress, diuretics, GI loss of bicarb and chloride.

-Bicarb & H are retained or excreted to adjust blood pH

-Phosphates are acidified to excrete H (phosphoric acid)

-(Amino acids ---> ammonia) + H ---> ammonium

-Lung disorders or chest wall abnormalities (lung compromised)

-Diabetes mellitus - fat breakdown = increased acidity

-Endocrine disorders

-Prolonged vomiting, gastric suction= loss of scids

-Diarrhea, abdominal wounds, ostomies= loss of bicarb (making it acidic)

-Newborns and Elderly

Causes of Respiratory Alkalosis?

pH>7.45

Hyperventilation

-Hypoxia, early PE, anxiety, pregnancy, high altitudes, fever, brain injury, pain.

Causes of Metabolic Alkalosis?

pH>7.45

-Loss of gastric juices (tubes or vomiting)

-Overuse of antacids

-Diuretics- K wasting- increases loss of H ions

ABG's

-Increased pH and decreased PCO2

-Possible decreased HCO3 (if compensating)

-Possible decreased PO2

Irregular pulse, muscle twitches, paralytic ileus (H ions move into ECF, K moves into ICF to keep neutrality which cause hypokalemia).

N/V, diarrhea, restlessness, irritability, disorientation, lethargy, tetany and seizures.

Shallow, slow respirations, decreased thoacic movements, cyanosis and apneic periods.

ABG's

-Increased pH, Increased HCO3

-Increased PCO2 (if compensating)

Causes of Respiratory Acidosis?

pH<7.35

-Hypoventilation

-Drugs (narcotic, anesthesia)

-CNS trauma

-Chest trauma

-Paralytic disorders (polio, guillian-barre, ALS, MS)

-Airway obstruction

-Resp diseases (COPD, Asthma, pneumonia, ARDs)

Kidneys excrete [H] and retain Na & HCO3.

Hyperventilation.

ABG's

-Increased PCO2, Decreased pH

-Increased HCO3 (if compensating)

-Possible decrease in PO2

Management of Respiratory Acidosis?

Causes of Metabolic Acidosis?

pH<7.35

Increased concentration of H.

-Production of ketoacids (DKA, starvation)

-Lactic acid build up (shock, cardiac/FVD, not sufficient O2 for metabolism of glucose)

-ASA overdose

Decreased HCO3

-Severe diarrhea

-Stomal drainage (esp Ileostomy)

-Renal failure- kidneys cant reabsorb HCO3- results in acid build up

-Early: Hyperventilation, HA.

-Later: Tachycardia r/t hyperkalemia (kidneys excrete H ions, so K retained), muscle twitches. Apathy, disorientation, weakness, stupor, coma r/t to decreased O2 to brain r/t O2 has a decreased affinity for HGB. 

-Late: Kussmaul's respirations.

-Hyperventilation to blow off CO2 (acid)

-Kidneys try to excrete H ions so K is retained

ABG's

-Decreased pH, Decreased HCO3

-Decreased PCO2 (if compensating)

-Possible decreased PO2

-Treat cause and s/s. 

-Na+HCO3

-Maintain fluid and electrolyte balance

anasarca

edema

brawny

edema