Body fluids are distributed into what two distinct compartments?
1. Extracellular
2. Intracellular
-Comprises all fluid within the cells of the body
-About 42% of total body weight
Intracellular Fluid (ICF)
-All the fluid outside a cell
-Divided into 3 parts
Extracellular Fluid (ECF)
What are the three smaller compartments of Extracellular Fluid?
1. Interstitial fluid
2. Intravascular fluid
3. Transcellular fluid
-The fluid between the cells and outside the blood vessels
-Contains lymph
Interstitial Fluid
Blood plasma found in the vascular system
Intravascular Fluid
Fluid separated from other fluids by a cellular barrier and consists of cerebrospinal, pleural, gastrointestinal, intraocular, peritoneal, and synovial fluids
Transcellular Fluid
An element or compound that, when dissolved or dissociated in water or another solvent, separates into ions that are electrically charged
Electrolytes
Positively charged electrolytes
Cations
Negatively charged electrolytes
Anions
Represents the number of grams of the specific electrolyte dissolved in a liter of plasma
milliequivalents per liter (mEq/L)
A substance that is dissolved in a solution
Solute
A liquid substance capable of dissolving other substances
Solvent
The movement of a pure solvent, such as water, across a semipermeable membrane from an area of lesser solute concentration to an area of greater solute concentration
Osmosis
Reflects the amount of a substance in a solution in the forms of molecules, ions, or both.
Osmols
-The drawing power of water
-Depends on the number of molecules in a solution
Osmotic Pressure
The concentration of an osmotic solution, which is measured in milliosmols per kilogram (mOsm/kg).
Osmolality or Osmolarity
A solution with the same osmolarity as blood plasma, indicating that the solutions on both sides of the semipermeable membrane are equal
Isotonic Solution
A solution of higher osmotic pressure that pulls fluid from cells causing them to shrink
Hypertonic Solution
A solution of lower osmotic pressure that moves fluid into the cells, causing them to enlarge
Hypotonic Solution
What may affect the osmotic pressure of blood
Plasma proteins
Pressure that tends to draw water into vessels. Osmotic forces counter the hydrostatic pressure in arterial capillaries which forces fluid out, so that ECF is drawn into venous capillaries.
Oncotic Pressure
The random movement of a solute in a solution across a semipermeable membrane from an area of higher concentration to an area of lower concentration
Diffusion
Difference in concentration of a substance on two sides of a membrane
Concentration Gradient
The process by which water and diffusible substances move together across a membrane, in response to fluid pressure, moving from an area of higher pressure to one of lower pressure. This process is active in capillary beds.
Filtration
Pressure exerted on the walls of blood vessels
Hydrostatic pressure
What is the process that happens resulting in edema?
1. Increased hydrostatic pressure on venous side of capillary bed
2. Reversal in the normal movement of water from the interstitial space into the intravascular space by filtration
3. Excess fluid accumulates in the interstitial space
Requires metabolic activity and expenditure of energy to move substances across cell membranes
-EX: Sodium-potassium-ATPase pump
Active transport
List the three ways that body fluids are regulated:
1. Fluid Intake
2. Hormonal Regulation
3. Fluid Output Regulation
Abnormally low blood volume
-EX: Excessive vomiting and Hemorrhage
Hypovolemia
Sensory receptors in the hypothalamus that detect changes in the osmotic pressure of the blood and surrounding extracellular fluids
Osmoreceptors
What is the average adult's fluid intake per day?
2200-2700 mL
A condition in which fluid loss exceeds fluid intake and disrupts the body's normal electrolyte balance
Dehydration
A hormone in the body that is stored in the posterior pituitary gland and maintains the water balance within the body by promoting the reabsorption of water through the kidneys
Antidiuretic Hormone (ADH)
What initiates the renin-angiotensin-aldosterone mechanism?
Changes in renal perfusion
-A proteolytic enzyme secreted by the kidneys
-Responds to decreased renal perfusion secondary to a decrease in extracellular volume
-Produces Angiotensin I
Renin
-Produced by Renin
-Causes some vasoconstrictions
-Is almost immediately reduced by an enzyme that converts this into the third part of this mechanism
Angiotensin I
-Causes massive selective vasoconstriction of many blood vessels
-Relocates and increases the blood flow to the kidneys
-Improves renal perfusion
-Stimulates the release of aldosterone when the sodium concentration is low
Angiotensin II
-Released from the adrenal cortex in response to increased plasma potassium levels or to help counteract hypovolemia
-Acts on the distal portion of the renal tubule to increase the reabsorption of sodium and the secretion and excretion of potassium and hy
Aldosterone
What is the overall effect of the renin-angiotensin-aldosterone mechanism?
-Sodium and Water retention
-To counteract Hypovolemia
-A hormone secreted from the atrial cells of the heart in response to atrial stretching and an increase in circulating blood volume
-Acts as a diuretic that causes sodium loss and inhibits the thirst mechanism
Atrial Natriuretic Peptide (ANP)
List the four organs of water loss
1. Kidneys (1500 mL)
2. Skin (300 mL)
3. Lungs (500 mL)
4. Gastrointestinal (200 mL)
Water loss that is continuous and occurs through the skin and lungs. A person does not perceive the loss, but it can be significant if a person has fever or burns.
Insensible Water Loss
Water loss that occurs through excess perspiration and can be perceived by the patient or through inspection. The amount of water loss is directly related to the stimulation of sweat glands. Other ex would be urination and diarrhea.
Sensible Water Loss
What stimuli affect the thirst mechanism?
1. Depleted potassium levels
2. Decreased plasma volume
3. Increased plasma osmolality
4. Angiotensin II
5. Dry pharyngeal mucous membranes
6. Psychological factors
What is the most abundant cation found in Extracellular Fluid?
Sodium
What is the normal range of Sodium found in body fluids?
135-145 mEq/L
What is the normal range of Potassium found in body fluids?
3.5-5.0 mEq/L
What is the normal range of Ionized Calcium found in body fluids?
4.5-5.5 mg/dl
What is the normal range of arterial Bicarbonate(HCO3-) found in body fluids?
Arterial: 22-26 mEq/L
What is the normal range of venous Bicarbonate(HCO3-) found in body fluids?
Venous: 24-30 mEq/L
What is the normal range of Chloride found in body fluids?
95-105 mEq/L
What is the normal range of Magnesium found in body fluids?
1.5-2.5 mEq/L
What is the normal range of Phosphate (PO4�-3) found in body fluids?
2.8-4.5 mg/dl
List the major cations within the body fluids:
1. Sodium (Na+)
2. Potassium (K+)
3. Calcium (CA2+)
4. Magnesium (Mg2+)
The major contributor to maintaining water balance through their effect on serum osmolality, nerve impulse transmission, regulation of acid-base balance, and participation in cellular reactions
Sodium ions (Na+)
The major electrolyte and principal cation in the intracellular compartment
Potassium
Regulates many metabolic activities and is necessary for glycogen deposits in the liver and skeletal muscle, transmission and conduction of nerve impulses, normal cardiac conduction, and smooth muscle contraction
Potassium
-Stored in bone, plasma, and body cells
-Necessary for bone and teeth formation, blood clotting, hormone secretion, cell membrane integrity, cardiac conduction, transmission of nerve impulses, and muscle contraction
Calcium
Essential for enzyme activities, neurochemical activities, and cardiac and skeletal excitability.
Magnesium
Regulated by dietary intake, renal mechanisms, and actions of the parathyroid hormone.
Magnesium
Regulated by dietary intake and aldosterone secretion
Sodium
The three major anions of body fluids:
1. Chloride (Cl-)
2. Bicarbonate (HCO3-)
3. Phosphate (PO4�-3)
The major anion in extracellular fluid
Chloride
Regulated by dietary intake and the kidneys
Chloride
The major chemical base buffer within the body
Bicarbonate
An essential component of acid-base balance. Regulated by the kidneys
Bicarbonate
A buffer anion found primarily in Intracellular Fluid to assist in acid-base regulation. Helps to develop and maintain bones and teeth.
Phosphorus-Phosphate
Regulated by dietary intake, renal excretion, intestinal absorption, and the parathyroid hormone
Phosphorus-Phosphate
A substance or group of substances that can absorb or release H+ to correct an acid-base imbalance
Buffer
What is the normal range of arterial pH?
7.35-7.45
Identify the three types of acid-base regulators in the body:
1. Chemical Regulation
2. Biological Regulation
3. Physiological Regulation
Abnormally high acidity (excess hydrogen-ion concentration) of the blood and other body tissues
Acidosis
Abnormally high alkalinity (low hydrogen-ion concentration) of the blood and other body tissues
Alkalosis
The first buffering system to react to change in the pH of Extracellular Fluid and it reacts within seconds
Carbonic acid-bicarbonate buffer system
-Occurs when hydrogen ions are absorbed or released by cells.
-Occurs after chemical buffering
Biological buffering
The two physiological buffers in the body:
1. Lungs
2. Kidneys
-A lower-than-normal concentration of sodium in the blood
-Can occur with a net sodium loss or net water excess
Hyponatremia
-A greater-than-normal concentration of sodium in the extracellular fluid
-Can be caused by excess water loss or an overall sodium excess
Hypernatremia
Lower-than-normal levels of potassium in the circulating blood
Hypokalemia
Higher-than-normal levels of potassium in the circulating blood
Hyperkalemia
Lower-than-normal levels of calcium in the circulating blood
Hypocalcemia
Higher-than-normal levels of calcium in the circulating blood
Hypercalcemia
What are the signs and symptoms of Hyponatremia?
1. Apprehension
2. Personality change
3. Hypotension
4. Dizziness
5. Abdominal cramping
6. Nausea and Vomiting
7. Diarrhea
8. Tachycardia
9. Dry mucous membranes
10. Convulsions
11. Coma
What are the signs and symptoms of Hypernatremia?
1. Extreme thirst
2. Dry and Flushed skin
3. Dry and Sticky tongue
4. Hypotension
5. Fever
6. Agitation
7. Convulsions
8. Agitation
9. Irritability
What are the signs and symptoms of Hypokalemia?
1. Weakness and Fatigue
2. Muscle weakness
3. Nausea and Vomiting
4. Intestinal distention
5. Decreased bowel sounds
6. Decreased deep tendon reflexes
7. Ventricular Dysrhythmias
8. Paresthesias
9. Weak pulse
Numbness, prickly, stinging, or burning feeling
Paresthesias
What are the signs and symptoms of Hyperkalemia?
1. Anxiety
2. Dysrhythmias
3. Paresthesia
4. Weakness
5. Abdominal cramping
6. Diarrhea
What are the signs and symptoms of Hypocalcemia?
1. Paresthesia
2. Hyperactive reflexes
3. Muscle cramps
4. Trousseau's sign
5. Chvostek's sign
6. Tetany
What causes hyponatremia?
1. GI losses (Vomiting, diarrhea, NG suction)
2. Renal loss (diuretics, adrenal insufficiency, kidney disease resulting in salt wasting)
3. Skin loss (Excessive perspiration, burns)
4. Psychogenic polydipsia
5. Inappropriate ADH
What causes Hypernatremia?
1. Excessive salt intake
2. Excess aldosterone secretion
3. Diabetes insipidus
4. Increased water loss
5. Water deprivation
What causes Hypokalemia?
1. Potassium-wasting diuretics
2. GI losses (diarrhea, vomiting)
3. Alkalosis
4. Excessive aldosterone secretion
5. Polyuria
6. Extreme sweating
What causes Hyperkalemia?
1. Renal failure
2. Fluid volume deficit
3. Burns/trauma
4. Adrenal insufficiency
5. Acidosis
6. Rapid infusion of blood
7. Potassium-sparing diuretics
8. Ingestion of K+ salt substitutes
What causes Hypocalcemia?
1. Rapid administration of blood transfusions containing citrate
2. Hypoalbuminemia
3. Hypoparathyroidism
4. Vitamin D deficiency
5. Pancreatitis
6. Alkalosis
7. Chronic renal failure
8. Chronic Alcoholism
Lower-than-normal levels of magnesium in circulating blood
Hypomagnesemia
Higher-than-normal levels of magnesium in circulating blood
Hypermagnesemia
Lower-than-normal levels of chloride in circulating blod
Hypochloremia
Higher-than-normal levels of chloride in circulating blood
Hyperchloremia
What are the signs and symptoms of Hypercalcemia?
1. Anorexia
2. Nausea and vomiting
3. Weakness
4. Lethargy
5. Flank pain (kidney stones)
6. Decreased level of consciousness
7. Personality changes
8. Cardiac arrest
What are the signs and symptoms of Hypomagnesemia?
1. Muscular tremors
2. Confusion and disorientation
3. Tachycardia
4. Hypertension
5. Dysrhythmias
6. Chvostek and Trousseau's signs
What are the signs and symptoms of Hypermagnesemia?
1. Acute elevations in magnesium levels
2. Hypoactive deep tendon reflexes
3. Decreased depth and rate of respirations
4. Hypotension
5. Flushing
The normal PaCO2 range
35-45 mm Hg
The normal PaO2 range
80-100 mmHg
What is the most accurate way to determine a patient's fluid status?
Daily Weight Measurements
Too low or too high potassium levels causes?
Cardiac Arythmia
Why are infants more prone to Fluid Volume Deficits than adults?
Infants have more body mass and Extracellular Fluid than adults and ECF is more easily lost, thus making them more vulnerable to fluid volume deficits
Expelling matter from the stomach through the mouth (vomiting)
Emisis
Normal range of Oxygen Saturation?
95%-99%
The amount of blood buffer (hemoglobin and bicarbonate) that exists
Base Excess
What is the normal range of Base Excess?
-2 to +2 mEq/L
Controlled by the lungs
Carbonic Acid
Controlled by the kidneys
Metabolic
-Increased PaCO2
-Excess carbonic acid
-Decreased pH
-Cause: Hypoventilation
Respiratory Acidosis
-Decreased PaCO2
-Increased pH
-Cause: Hyperventilation
Respiratory Alkalosis
-Decreased pH
-Decreased bicarbonate
-PaCO2 is normal or low
-PaO2 is normal or increased
Metabolic Acidosis
-Increased bicarbonate
-Increased pH
-PaCO2 is normal or high
-PaO2 is normal
Metabolic Alkalosis
What are the risk factors for fluid, electrolyte, and acid-base imbalances?
1. Age (very young, very old)
2. Gender (women)
3. Environment (diet, exercise, hot weather, sweating)
4. Chronic diseases (Cancer, cardiovascular, CHF, diabetes, malnutrition, COPD, renal)
5. Trauma (crush & head injuries, burns)
6. Therapies (diuretics,
Medications that cause fluid, electrolyte, and acid-base imbalances:
1. Diuretics
2. Steroids
3. Potassium supplements
4. Respiratory center depressants (Opioids)
5. Antibiotics
6. Calcium carbonate (Tums)
7. Magnesium hydroxide (Milk of Magnesia)
8. Nonsteroidal antiinflammatory drugs
Toxicity to the kidneys, often drug-induced and manifesting in compromised renal function.
Nephrotoxicity
What are the three isotonic IV solutions?
1. Dextrose 5% in water
2. 0.9% normal saline
3. Lactated Ringer's
What are the two hypotonic IV solutions?
1. 0.45% normal saline
2. 0.33% normal saline
What are the five hypertonic IV solutions?
1. Dextrose 5% in water
2. 3%-5% sodium chloride
3. Dextrose 5% in 0.9% sodium chloride
4. Dextrose 5% in 0.45% sodium chloride
5. Dextrose 5% in lactated Ringer's
Abnormal redness of the skin resulting from dilation of blood vessels (as in sunburn or inflammation)
Erythema