Fluids & Electrolytes Flashcards
Fluid found outside the cells. It accounts for about 1/3 of total body fluids and is subdivided into compartments. The 2 main compartments of ECF are Intra-vascular and Interstital. Principle electrolytes are Na, Cl, & HCO3.
Extracellular fluid (ECF)
Fluid found with in the body cells that contain solute vital to the metabolic processes of the cells. aka cellular fluid. transport system-waste from cells by the lymph system and directly into the blood plasma via capillaries.
Intracellular fluid (ICF)
A charged ion capable of conducting electricity.
Electrolytes
Substances that dissolve in liquid
Solutes
Salts that dissolve rapidly in true solutions
Crystalloids
Osmolality
A measure of the concentration of solutes in the body fluids. Osmolality is determined by the total solute concentration within a fluid compartment and is measred as parts of solute per kilogram of H2O. Na is greatest determinant.
Refers to solutions that have a higher osmolality than body fluids; 3% sodium choloride is a hypertonic solution.
Hypertonic
Substantial loss of both water and electrolytes in similar proportions from the extracellular fluid (ECF). Also called
hypovolemia
FVD; fluid volume deficit
Excessive fluid retained by the body. The retention of both water and sodium in similar proportions to normal extracellular fluid (ECF). Also called hypervolemia
FVE; fluid volume excess
A pulling force exerted by colloids that helps maintain the water content of blood by pulling H20 from the interstitial space into the vascular compartment. Also called oncotic pressure
Colloid Osmotic Pressure
A process whereby fluid and solutes move together across a membrane from a compartment with higher pressure to a compartment with lower pressure.
Filter
Filtration; filter
A method that requires additional energy (in the form of Adenosine triphosphate-ATP) to move substances against the concentration gradient. (from low concentration to high)
Active Transport
A condition that occurs when a body does not take in as much H20 as it loses or lack sufficient reserves to maintain proper function.
Dehydration
The body’s ability to maintain a state of physiological balance in the presence of constantly changing conditions
Homeostasis
System initiated by specialized receptors in the juxtaglomerular cells of the kidneys nephrons that respond to changes in renal perfusion.
Renin-Angiotensin-Aldosterone System
RAAS
The proportion % of CELLS and PLASMA in blood. Also, refers to the laboratory tests that measures hematocrit.
This can be used to detect severe dehydration or overhydration.
Hematocrit; HCT
The most abundant cation in extra cellular fluid (ECF) & a major contributor to serum osmolality.
Norms; serum levels 135-145 mEq/L. Controls and regulates H20 balance.
Sodium; Na+
The chemical combining power of the ion, or the capacity of cations to combine with anions to from molecules.
Milliequivalent
Substances such as large protein molecules that do not readily dissolve into true solutions.
Colloids
The osmolality of a solution. Solutions maybe termed isotonic, hyper-tonic, or hypotonic.
Tonicity
Refers to solutions that have a lower osmolality than body fluids 0.9% , such as one half normal saline. 0.45%
Hypotonic
A pulling force exerted by colloids that helps maintain the H20 content of blood by pulling H20 from the interstitial space into the vascular compartment. Also called Colliod osmotic pressure.
Oncotic Pressure
The pressure a fluid exerts with in a closed system on the walls of its container. The hydrostatic pressure of blood is the force blood exerts against the vascular walls (ie. artery walls). The principle involved in hydrostatic pressure is that fluids move from an area of greater pressure to an area of lesser pressure
Hydrostatic pressure
Fluid loss that is not perceptible to the individual & cannot be measured.
Insensible Loss
Small molecule released by the pituitary gland that has an antidiuretic action that prevents the production of urine dilute.
ADH; anti-diuretic hormone
K+; a major cation in the intracellular fluids, with ony a small amount found in plasma and interstitial fluid. ICF levels of potassium are 125-140 mEq/L serum 3.5-5.3 mEq/L. Vital electrolyte for skeletal, cardiac, and smooth muscle activity. [acid-base balance]
Potassium
Cl; major Anion of ECF and normal serum levels are 95-105 mEq/L. Functions with Na+ to regulate serum osmolality and blood volume. When Na is absorbed into the kidneys Cl usually follows. [acid-base balance]
Chloride
The movement of water across cell membranes, from a less concentrated solution to a more concentrated solution.
Osmosis
The component of a solution that can dissolve a solute.
Solvent
A solution that has the same osmolality as body fluids. 0.9% Sodium Chloride, is a isotonic solution.
Isotonic
The power of a solution to draw water across a semipermeable membrane.
Osmotic Pressure
The continual intermingling of molecules in liquids, gases or solids brought about by the random movement of the molecules.
Diffusion
Essential fluid losses required to maintain body functioning.
Obligatory (compulsory) loss
Vast majority (99%), of Ca in the body is in the skeletal system, with small amount of extracellular fluid. Vital in regulating muscle contraction and relaxation, neuromuscular function and cardiac function. In Dairy
Calcium; Ca2+
primarily found in the skeleton and intracellular fluid. 2nd most abundant. Mg2+
Magnesium; Mg2+
Major anion of ICF. (intracellular fluid) Also found in ECF, bone, skeletal muscle, and nerve tissue. Normal adult serum levels are 2.5 to 4.5 mg/dL. Children have much more higher PO4 levels than adults prob b/c of growth hormone. Calcium and Po`4 bind.
Phosphate; Po`4
present in both ICF & ECF; primary function is regulating Acid-Base Balance. an essential component of the carbonic acid-bicarbonate buffering system
Bicarbonate; HCO`3
Powerful vasodilator and protein hormone; secreted by the heart muscle cells. involved with homeostatic control of body water, sodium, potassium, and fat.
ANF; atrial natriuretic peptide hormone
movement of H2o across cell membranes; from the less concentrated solution to the more concentrated solution. H2O moves toward the higher concentration of solute in an attempt to equalize the concentrations on either side of the membrane.
This higher solute concentration draws H2o from the interstitial space and cells into the vascular compartment to equalize the concentration of solutes in all fluid compartments. Osmosis is an important mechanism for maintaining homeostasis and fluid balance.
Osmosis
monitors kidney & liver function, diabetes and parathyroid status, electrolyte-fluids and acid-base balance
BMP/CMP; Comprehensive metabolic panel (14 tests including BMP) & basic metabolic panel (glucose, electrolytes-na, chloride,potassium, CO2 & calcium) BUN, creatinine
Complete blood count RBC, WBC, HCT, HGB, Platelets Possible dehydration HCT up Male: 41 to 50% Female: 36 to 44%
CBC
Na+ 135-145 mEq/L
Maintains water balance throughout the body, controls and regulates the volumes and distribution of ECF.
Sources: Table salt, cheese, processed foods, snack foods
Recommended daily allowance: 0.5 to 2.4 g/day
Sodium+
Ca++ 4.25-5.25mg/dL ionized 9-11 mg/dL serum
Most abundant electrolyte in body, 99% found in bones and teeth
Necessary for strong bones & teeth, necessary for nerve impulse, and blood clotting, a catalyst for muscle contraction, is needed for B12 absorption
Sources: Milk, cheese, dairy products, dried peas, green leafy vegetables, fortified bev. like OJ
Calcium and phosphorus levels inversely proportional Ca & PO4 opposite ways!!
Calcium++
Mg++ 1.5-2.5 mEq/L
- Found in intracellular, in the heart, bone, nerve, and muscle tissue, 2nd most important anion in ICF
- Important in the metabolism of proteins and carbohydrates, important in many vital reactions that involve enzymes, maintains normal levels of potassium
- Helps maintain electrical activity in nervous and muscle tissue
Sources: most foods but esp. in Fish, Nuts, green leafy vegetables, whole grains, dried peas, and beans, chocolate and cocoa
RDA: 400-420 mg/day men
310-350 mg/day women
Magnesium++
Cl` 95-105 mEq/L
-Chief extracellular anion
Found in blood, interstitial fluid/lymph
-Acts with Sodium to maintain osmotic pressure of the blood.
-Is essential in the production of Hydrochloric acid in gastric juices
Sources: Foods high in sodium, processed food, dairy products, meat
Deficits lead to potassium deficits. potassium deficits lead to chloride deficits Cl & K Same way!
Chloride
PO4+ 2.5-4.5 mq/dL
Helps the body maintain acid-base balance, necessary for B Vitamins to be effective, helps promote nerve and muscle action, plays a role in carbohydrate metabolism. Bone and teeth formation.
Sources: All animal products (meats, poultry, eggs, milk), bread, ready to eat cereal
RDA: 700mg/day
Calcium and PO4 bind in blood
Important for cell division and transmission of hereditary traits
Serves as a catalyst for many intracellular activities
Excreted and reabsorbed by the kidneys
Phosphate
K+ 3.5-5.3 mEq/L
- Major cation of the intracellular fluid
- K+ & Cl- go hand in hand; one goes down so does the other
- Plays a vital role in processes like the transmission of electrical impulses, particularly nerve, heart, skeletal, intestinal and lung. Assist in acid base balance.
- Think Cardiac Rhythm Disturbances
causes of hypokalemia:
Diarrhea, loss of GI fluids, diuretics, steroid use, poor intake
S&S of hyporkalemia: Anorexia, fatigue, cardiac arrhythmia, increased sensitivity to digitalis muscle weakness, tender muscles, EKG changes
causes of Hyperkalemia: High Intake, renal failure, shift of K+ out of cells
S&S of hyperkalemia: Vague muscle weakness, cardiac arrhythmias, GI symptoms, parasthesias or tender muscles
Sources: Bananas, peaches, oranges, dates, figs, melons, broccoli, potatoes, dried peas, and beans, whole grains
Potassium+
constantly varies in 24hr; 0.5 lbs/0.2 kg
Body weight
Processes that regulate the balance of water and electrolytes and conditions that contribute to imbalances
Concepts of Fluid/Electrolytes
Total Body Weight (TBW) 45% to 75%
Varies with age, body fat, gender
Intake/Output should be equal
Composition/Distribution
Medium for transport
Facilitate metabolism and cellular function
Solvent for electrolytes and non-electrolytes
Maintain body temperature
Facilitate digestion
Promote elimination
Tissue lubricant
Primary function of water
Atom/molecule carrying an electric charge
Ion
Substance capable of breaking into electrically charged ions then dissolved in solution.
Measured in mEq/L (milliequivalents)
Electrolyte
Positively charged ions
Na, K, Mg, Ca
Cations
Negatively charged ions
Cl, PO4, HCO3
Anions
Fluid compartments
K+, Mg+, PO4-, other electrolytes
Intracellular ICF
Fluid compartments
Na+, Cl-, HCO3
- Interstitial-between the body cells
- Intravascular (Plasma)-transport blood cells
- Transcellular-Cerebrospinal, pleural, peritoneal, synovial, digestive
Extracellular ECF
Primary mode of movement
Water moving from less concentrated area to higher concentrated area
Isotonic Hypertonic Hypotonic Osmolarity Osmotic potential
Movement: Osmosis
Intermingling of molecules -Liquids -Gases -Solids Higher concentration; low concentration Equalizer
Movement; Diffusion
Movement of molecules
Lower concentration higher concentration
Must have ATP to occur
Na+-K+ pump
Movement: Active Transport
Movement of water & particles
High pressure low pressure
Movement between vascular compartment and interstitial fluid
Hydrostatic pressure: pressure that builds in a closed container.
Osmotic pressure: power of a solution to draw water from a semipermeable membrane
Movement: Filtration
Intake of fluids a day: 1500-2000 ml/24hr
or 40-80 ml/hr need 2500 ml intake but some from food
Output: 1400-1500ml
take weight; 0.5ml/kg per hr.
Fluid balance: Gains & Losses
Thirst: regulated by the hypothalamus ev. 15-20 mins then thirsty again
Kidneys: main organ for excretion. Filter 1500 ml/day & 170 ml of plasma/day
Systolic below 60 mmHg-organ not getting enough blood.
Hormones:
-Antidiuretic hormone ADH- helps kidneys to retain fluid
fever, pain, stress, some opioids
-Renin-Angiotensin System:
-Aldosterone
-Thyroid hormone
-Natiuretic Peptide; Atrial (ANP), Brain (BNP), C-type (CNP)
Regulation of Fluid Volume
Regulation of water distribution
Transmission of nerve impulses
Clotting of blood
Regulation of acid-base balance
Electrolyte Function
HCO3- Normal 22-28
Major buffer
In both ICF & ECF
Function: Maintains acid-base balance by functioning as the primary buffer in the body
Regulation:
Lost through diarrhea, diuretics, renal insuffiency
Excess possible if person ingests quantities of acid neutralizers
Sources:
Acid neutralizers (sodium bicarbonate)
Tums, Rolaids, Malox, Mylanta
Kidneys conserve & secrete
Bicarbonate HCO3-
Carbonic Acid-Sodium bicarbonate system
Lungs=carbonic acid
Kidneys=bicarbonate
Respiratory system and Renal system balance
Kidneys conserve bicarbonate, and secrete bicarb. (long term fix)
pH too low-too acidic
pH too high-lungs conserve O2
Lungs get rid of 02 by quick breathing
Lungs conserve by slow, very shallow breaths
Systems that Regulate of Acid-Base Balance
7.35-7.45
pH blood
low blood volume
proportional loss of fluid/electrolyte from ECF
hypovolemia
heart rate blood pressure skin/mucous membranes urine output neck veins-flat, distended? muscles, weak, fatigued? temperature Labs
Fluid Loss Assessment
Low K+ level-K rider-Magrider
Colloid & Crystalloids-IV fluids to expand blood volume
Diuretics to pull fluid off
Pharmacology Fluids/Electrolytes
Daily Weights
Vital Signs
I/O
1 kg=1L Fluid or 1, 000 ml fluid
Tachycardia sign of hypovolemia (decreased blood vol)
Clinical Measurements
