HAPP 1 - Fluids + Electrolytes, Acids + Bases

Passive Transport

Molecules move from high concentration to low concentration; no energy

Active Transport

Molecules move against the gradient, low to high; requires energy

Examples of Passive Transport

Osmosis, hydrostatic pressure (filtration), diffusion

Intracellular Fluid

Fluid (water) inside the cells; makes up 40%

Extracellular Fluid

Fluid (water) outside the cell; makes up 20%

Interstitial Fluid

makes up 15%

Intervascular Fluid

Found in blood vessels; makes up 5%

Children have (more/less/same) amount of fluids as adults

More

Fluid compartment that has the highest % of body water

Intracellular fluid

Extracellular electrolyte (cation)

Sodium (Na+)

Intracellular electrolyte (cation)

Potassium (K+)

Extracellular electrolyte (anion)

Chlorine (Cl-)

Intracellular electrolyte (anion)

Hydrogen phosphate (HPO4-)

Osmolality

Measure of solute in moles/kg solution (osm/Kg)

Osmolarity

Number of mole of electrolytes/L solvent (osm/L)

Electrolytes are typically measured in

mEQ

Tonicity

Measure of the ability of a solution to force the movement of water

Isotonic

Water moving in and out of the cell at equal volumes (equilibrium)

Hypotonic

Water moving into the cell at a greater rate than water moving out of the cell

Hypertonic

Water moving out of the cell at a higher rate than moving into the cell

Diffusion

Movement of solutes (NOT WATER) from high concentration to low concentration

Diffusion rate is influenced by

Electrical potential

Size

Lipophilicity or hydrophobicity

Filtration

Movement of water AND solutes across membrane due to differences in thermodynamic forces on opposite sides of membrane

Fluid moving out

Osmosis

Diffusion of water down a concentration gradient

Thermodynamic forces of filtration

Blood pressure

Hydrostatic pressure

Osmotic Pressure

Pressure required to prevent water from moving by osmosis to solute-containing region

Oncotic Pressure

Pressure due to solutes other than ions

Forces favoring filtration

Capillary hydrostatic pressure (blood pressure)

Interstitial oncotic pressure (water-pulling)

Forces favoring reabsorption

Capillary oncotic pressure (water-pulling)

Interstitial hydrostatic pressure

Edema (swelling)

Accumulation of fluid in interstitial places

Edema forces/causes

Increased capillary hydrostatic pressure

Decreased plasma oncotic pressure

Increased capillary permeability

Lymph obstruction

Renin is an ______ that is released from the ______

Enzyme; kidneys

Renin converts _____ to _____

Angiotensinogen; angiotensin I

This enzyme converts angiotensin I to angiotensin II

Angiotensin converting enzyme (ACE)

Angiotensinogen circulates in _____ and is secreted by ______

Blood; kidneys

Hypernatremia

More sodum, loss of water, or both

Hyponatremia

Less sodium, too much water, or both

Hypernatremia signs + symptoms

Thirst, weight gain, bonding pulse, increased blood pressure

Hyponatremia signs + symptoms

Cerebral edema, increased intracranial pressure, lethargy, confusion, decreased reflexes, seizures, coma

Hypochloremia results from

Hyponatremia

Elevated bicarbonate concentration

Vomiting and result of HCl loss

Cystic fibrosis

Hypokalemia results from

Reduced K+ intake

Increased intracellular K+

Increased loss of K+

Hyperkalemia results from

Increased K+ intake

Shift of K+ from ICF to ECF

Decreased renal excretion (kidney disease)

Insulin deficiency

Calcium concentrations controlled by

Parathyroid hormone

Vitamin D

Calcitonin

99% of calcium is found in

The bones

Calcium is required for

Bone structure

Blood clotting

Hormone secretion

Cell receptor function

Plasma membrane stability

Transmission of nerve impulses

Muscle contraction

Hypocalcemia causes

Decreased intestinal absorption

Decreased dietary consumption

Increased reabsorption in bone

Decreased PTH and vitamin D

Hypocalcemia effects

Increased neuromuscular excitability

Convulsions (severe)

Cardiac arrest

Hypocalcemia treated by

Dietary supplement of Ca2+ and/or vitamin D

Hypercalcemia causes

Hyperparathyroidism

Bone metastases with calcium resorption

Tumors that produce PTH

Hypercalcemia effects

Fatigue, weakness, nausea, constipation

Renal dysfunction, kidney stones

Cardiac arrest

Negative Logarithm of H+ Concentration

pH = -log[H+]

Changes in pH can affect

Protein structure, enzyme active sites, drug activity, electrolyte balance

Two Forms of Body Acids

Volatile (H2CO3) and Nonvolatile (Phosphoric and other organic acids)

A buffer is

A chemical that can bind excessive H+ or OH- without a significant change in pH

Most important plasma-buffering system is

The carbonic acid-bicarbonate pair

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Other buffering systems

Protein buffering (hemoglobin)

Renal buffering

The carbonic acid- bicarbonate pair operates in

Lungs and kidneys

The ratio of HCO3- to H2CO3 that must be maintained when pH = 7.4

20:1

Respiratory system compensates for acidosis by

Increasing ventilation to expire CO2

Respiratory system compensates for alkalosis by

Decreasing ventilation to retain CO2

The renal system (kidneys) can compensate by

Producing acidic or alkaline urine

The normal arterial blood pH is

7.35 to 7.45

Acidosis is systemic

Increase in [H+] or decrease in HCO3-

Alkalosis is systemic

Decrease in [H+] or increase in HCO3-

Categories of Acid-Base Imbalances

Respiratory Acidosis/Alkalosis, Metabolic Acidosis/Alkalosis

Respiratory Acidosis

Increased CO2 as a result of depressed ventilation

Respiratory Alkalosis

Releasing a lot of CO2 as a result of hyperventilation

Metabolic Acidosis

Depression of HCO3- or increased non carbonic acids

Metabolic Alkalosis

Increased HCO3- due to loss of metabolic acids

Respiratory Acidosis Compensation

Renal bicarbonate (HCO3-) retention and hydrogen elimination

Metabolic Acidosis Compensation

Respiratory CO2 elimination (hyperventilation)

Respiratory Alkalosis

Renal HCO3- elimination and hydrogen retention

Metabolic Alkalosis

Respiratory CO2 retention (hypoventilation)