1	EMP 194 Fluids and Electrolytes
2	Fluids and Electrolytes Water is the main component of body mass. It is approx. 60% of the total body weight (TBW). Importance of body water It is a medium for metabolic reactions Precise regulation is necessary for health A loss of 20-25% of the TBW is usually fatal
3	Extracellular Fluid Water outside the cells Found in: Intravascular spaces – in the vessels Interstitial spaces – between the cells Makes up 20% of the TBW
4	Intracellular Fluid Is the water found inside the cells Makes up 40% of the TBW
5	Water in the Body Water is approximately 60% of the body’s weight. 20% of that is extracellular 40% of that is intracellular
6	Electrolytes Salt substances that have an electrical charge in water. Cation – a positively charged electrolyte Anion – a negatively charged electrolyte
7	Cations Intracellular Potassium (K⁺) – most important Intracellular cation Calcium (Ca⁺²) Magnesium (Mg⁺²) Extracellular Sodium (Na⁺)
8	Anions Intracellular Phosphate (PO₄^-3) Extracellular Chloride (Cl^-) Bicarbonate (HCO₃^-)
9	Particles and Solutions A solution is a liquid (or gas) that contains one or more solutes. The liquid is called the solvent. Example: Salt water Salt is carried…it is the solute Water is the carrier…it is the solvent
10	Milliequivalents Milliequivalents are based on the amount of an ion that will completely react with another ion. One meq of anything combines completely with one meq of anything else. One Ca⁺⁺ ion needs two Cl^- ions to combine One mEq of Ca⁺⁺ needs two mEq of Cl^- to combine
11	Movement of Body Fluids The volume of fluid in each area should remain basically the same. This is accomplished by: Osmosis Diffusion Mediated transport
12	Osmosis Osmosis is the flow of a fluid (water) across a semi permeable membrane from an area of lower solute (solid) concentration to an area of higher solute (solid) concentration. Ex: Water in a low salt solution will move to a solution higher in salt concentration if separated by a semi permeable membrane.
13	Semi permeable Membrane Membranes that allow water to freely pass through them but restrict flow of solutes. They filter out the solid and allow the water to pass through
14	Types of Fluid Hypertonic Hypotonic Isotonic
15	Hypertonic Fluids Higher solute (solid) concentration than the cells. Causes water to move out of the cells. The cells shrink. Examples: Mannitol Sodium bicarbonate D₅₀W
16	Hypotonic Fluids Lower solute (solid) concentration than the cells. Causes water to move into the cells. The cells will swell or even explode. Examples: 0.45% Sodium Chloride (1/2 NS) D₅W
17	Isotonic Fluids The solute concentration is equal to the cells. Causes no noticeable water movement. Examples: 0.9% Normal Saline (NS) Note: D₅W is technically isotonic, but behaves as a hypotonic fluid.
18	Diffusion A passive process that moves PARTICLES (not water) from an area of higher concentration to an area of lower particle concentration. Solutes will diffuse down a concentration gradient until equilibrium is achieved.
19	Mediated Transport Two kinds Activated Transport Facilitated Diffusion
20	Active Transport A carrier mediated process that can move substances against a concentration gradient (from a lower concentration to a higher concentration). Occurs faster than diffusion. Requires energy.
21	Facilitated Diffusion A carrier mediated process that moves substances from an area of higher concentration to an area of lower concentration. (Movement with the concentration gradient.) This is simply diffusion sped up. Does not require energy.
22	Body Fluids and Fluid Imbalances The body normally gains fluid by: Drinking fluids Ingesting foods containing water The body normally loses fluid by: Excretion of urine Excretion of fluid Perspiration Exhaled as vapor
23	Hydration Status Dehydration – the amount of fluid lost exceeds the amount of fluid gained. Overhydration – the amount of fluid gained exceeds the amount of fluid gained.
24	Dehydration Three types: Isotonic dehydration Hypernatremic dehydration Hyponatremic dehydration
25	Isotonic Dehydration Usually caused by vomiting and/or diarrhea. Signs and Symptoms Dry skin and mucous membranes Poor skin turgor Oliguria – low urinary output (100 – 400 ml/24 hr) Anuria – no urinary output (less than 100 ml/24 hr) Sunken fontanelles in infants
26	Isotonic Dehydration Treatment IV infusion of an isotonic solution
27	Hypernatremic Dehydration Causes Diuretic abuse Sodium administration without fluid intake Excessive loss of water with little loss of salt Profuse, watery diarrhea Inhalation or ingestion of saltwater
28	Hypernatremic Dehydration Signs and Symptoms Dry, sticky membranes Flushed skin Intense thirst Oliguria or anuria Treatment IV infusion of an isotonic or possibly hypotonic solution
29	Hyponatremic Dehydration Causes Diuretic use Excessive perspiration Increased water intake Inhalation or ingestion of fresh water
30	Hyponatremic Dehydration Signs and Symptoms Abdominal or muscle cramps Seizures Rapid, thready pulse Diaphoresis Cyanosis Treatment IV infusion of NS or LR A hypertonic solution is occasionally used
31	Overhydration Signs and Symptoms Dyspnea Edema Polyuria Wet lung sounds Treatment is diuretic solution
32	Electrolytes Potassium Calcium Magnesium Sodium
33	Potassium (K⁺) The major intracellular cation. Normal value is 3.5 – 5.0 mEq/L Has a role in: Muscle contraction Nerve impulses Cell membrane function Imbalances interfere with neuromuscular function and may cause cardiac rhythm disturbances
34	Hypokalemia Serum level below 3.5 mEq/L Causes Reduced dietary intake Poor absorption by the body Vomiting and/or diarrhea Renal disease Medications (typically diuretics)
35	Hypokalemia Signs and Symptoms Malaise – general feeling of weakness Skeletal muscle weakness Decreased reflexes Hypotension Vomiting Excessive thirst Treatment: Inhospital IV or Oral replacement of Potassium
36	Hyperkalemia Serum level above 5 mEq/L Causes: Chronic or acute renal failure Burns Crush injuries Excessive use of Potassium salts
37	Hyperkalemia Signs and Symptoms: Irritability Nausea Diarrhea Oliguria (100 – 400 ml urine output/24 hours) Weakness and paralysis Treatment: IV administration of glucose and insulin helps lower serum Potassium levels. Sodium Bicarbonate also causes potassium to shift into the cells.
38	Calcium (Ca⁺⁺) Essential for Neuromuscular transmission Growth and ossification of bones Muscle contraction Excreted through urine, feces, and perspiration
39	Hypocalcaemia Decrease in serum calcium Causes Renal insufficiency Decreased intake or malabsorption of Calcium Deficiency in or inability to activate Vitamin D
40	Hypocalcaemia Signs and Symptoms Paresthesia Tetany (cramps/convulsions in wrists and ankles) Abdominal and muscle cramps Personality changes Abnormal behavior Treatment: Inhospital IV administration of Calcium
41	Hypercalcemia Excess of serum Calcium Causes Neoplasms (tumors) Excessive administration of Vitamin D
42	Hypercalcemia Signs and Symptoms Hypotonicity of muscles (decreased muscle tone) Renal stones Altered mental status Treatment: Usually aimed at underlying disease and hydration Severe hypercalcemia may be treated with forced diuresis
43	Magnesium (Mg⁺⁺) Activates many enzymes 50% is insoluble in bone 45% is intracellular 5% is extracellular
44	Hypomagnesemia Low magnesium levels Caused by: Alcoholism Malabsorption Starvation Diarrhea Diuresis
45	Hypomagnesemia Signs and Symptoms Tremors Diarrhea Hyperactive deep reflexes Confusion/Hallucinations Seizures Dysrhythmias Treatment: IV administration of Magnesium Sulfate
46	Hypermagnesemia Excess of Magnesium Occurs with chronic renal insufficiency
47	Hypermagnesemia Signs and Symptoms CNS Depression Areflexia Sedation Respiratory paralysis Treatment is hemodialysis
48	"Questions???" Questions???