What are the Units of Concentration for Weight/Volume %?
Grams100 ml
What are the Units of Concentration for Volume/Volume %?
mL or L of solute mL or L of solution
then multiplied by 100
Basically...
PartTotal TIMES 100
What is Henry's Law?
The solubility of a gas is directly proportional to the partial pressure of the gas if the temperature is constant
What is the formula for Henry's Law?
Solubility (Concentration) =k
Partial Pressure of Gas
(k is at constant temperature)
C1 = C2
P1 P2
Shubert uses S
P
True or False: Solubility is Temperature Dependent
TRUE.
(a) What is the solubility coefficient?
(b) If the solubility coefficient is low, what does that say about the solubility of the gas?
(c) What does a low coefficient say about partial pressure?
(a) k
(b) the smaller the coefficient, the less soluble the gas is in the liquid
(c) lower the coefficient the greater the partial pressure in whatever liquid it's dissolved in
What are the units of the solubility coefficient?
mL
dL Blood/mmHg
can turn mL into volume/volume %
dL/ mmHg
by making units in the equation the same
Partial Pressure of Gas in a solution is determined by: (2 Things)
(1) Concentration of then gas in the solution
(2) The solubility coefficient
What is a colligative property?
Examples?
A property of a solution that depends on the number of dissolved particles, not their chemical identity
Ex. vapor pressure, boiling point, freezing point, osmosis
What is vapor pressure?
The pressure of gas particles moving against the walls and cover of the container they're in
The solubility of Gases is Dependent On:
(4 Things)
1. concentration & partial pressure
(Henry's Law)
2. Temperature
3. The Gas (solute)
4. The Liquid (solvent)
True or False: Nitrous Oxide is very soluble in blood.
False.
Why wouldn't you chose to give Nitrous Oxide to a patient with an air embolism or pneumothorax?
Nitrous Oxide will increase the volume of air space [due to it's high solubility] and potentially cause bigger problems
What is the Bunsen Coefficient?
The volume of gas which dissolves in 1 unit of volume of the liquid at standard atmospheric pressure and temperature.
What is the Ostwald Coefficient?
Volume of gas dissolved in a particular volume of liquid at a specific temperature.
-Refers to the relative ability of the gas to dissolve in a liquid
-Key is the ratio between 2 phases (gas&liquid)
What is the Partition Coefficient?
The ratio of the amount of a substance present in one phase compared with another, the two phases being of equal volume and in equilibrium.
-Equilibrium refers to identical partial pressures
True or False: The solubility of a gas is increased when the temperature of a liquid decreases.
True.
Partition coefficients *unless otherwise stated* are defined at what temperature?
37 degrees Celsius
(because humans are 37 degrees celsius!)
Partition coefficients *unless otherwise stated* are defined at what temperature?
37 degrees celsius
(because humans are 37 degrees celsius!)
The smaller the partition coefficient the __________ the pressure builds up in the blood.
(slower/faster)?
FASTER.
The bigger the partition coefficient the __________ the pressure builds up in the blood.
(slower/faster)
SLOWER.
True or False: Partition coefficient indicates solubility and potency of the gas.
FALSE.
The partition coefficient only indicates the solubility of the gas.
What does MAC stand for?
Minimum Alveolar Concentration
(volume percent at the Alveoli)
By definition what is 1 MAC representative of?
One Mac= the concentration of anesthetic (in volume %) that will prevent movement in 50% of patients in response to a noxious stimuli
The Greater the oil:gas partition coefficient, the ____________ the MAC.
(Higher/Lower)
Lower.
The Lower the MAC the __________ potent the anesthetic.
(less/more)
MORE.
What is the (1) Blood:Gas Coefficient, (2) MAC, and (3) Vapor Pressure for Isoflurane?
(1) 1.46
(2) 1.17
(3) 240
What is the (1) Blood:Gas Coefficient, (2) MAC, and (3) Vapor Pressure for Enflurane?
(1) 1.9
(2) 1.63
(3) 172
What is the (1) Blood:Gas Coefficient, (2) MAC, and (3) Vapor Pressure for Halothane?
(1) 2.54
(2) .75
(3) 244
What is the (1) Blood:Gas Coefficient, (2) MAC, and (3) Vapor Pressure for Desflurane?
(1) .42
(2) 6.6
(3) 669
What is the (1) Blood:Gas Coefficient, (2) MAC, and (3) Vapor Pressure for Sevoflurane?
(1) .69
(2) 1.80
(3) 160
What is the (1) Blood:Gas Coefficient, (2) MAC, and (3) Vapor Pressure for Nitrous Oxide?
(1) .47
(2) 104
(3) not given in chart.
What is the "hungover" affect attributed to, and how does it relate to our inability to ever fully reach a "steady state"?
No steady state because drug goes to muscle and fat groups. Even after anesthetic is turned off, the areas of lower perfusion (muscle/fat) are still recycling drug and releasing back into blood stream and then brain (as long as there is still a difference in the pressure gradient)...
Thus creating the "hungover" effect.
What are the two types of Gated Protein Channels?
(1) Voltage-gated Channel: electrical potential difference across the membrane that's responsible for the gate opening and closing
(2) Ligand-gated Channel: Ligand another name for drug or neurotransmitter; for example acetylcholine channel, GABA
What is the definition of Osmosis?
The movement of water between compartments through a semi-permeable membrane which occurs when the concentrations of solutes of either side of the membrane are unequal.
What is the definition of Osmotic Pressure?
The pressure needed to oppose the movement of water down a solute concentration gradient across a cell membrane.
What is Osmolarity?
Quantifies the forces determining the distribution of water and refers to the number of osmotically active particles per liter of solution
What is Osmolality?
Measure of the osmotically active particles per kilogram of solvent
What defines an isotonic fluid in relation to the blood?
Same tonicity/ osmolarity of the blood
What defines a hypotonic fluid in relation to the blood?
Cells swell because water goes into the cell
What defines a hypertonic fluid in relation to the blood?
Water leaves the cell and tries to equilibrate across the cellular membrane
What units are molarity in?
moles
L
Molarity and Osmolarity are __________ for a molecular compound.
EQUAL.
What are the units for osmolarity?
osm
L
Molarity and Osmolarity are ___________for an ionic compound.
NOT EQUAL.
What are the two pressures involved in Starling Forces?
(1) Colloid Osmotic Pressure
(2) Hydrostatic Pressure
Does Colloid Osmotic Pressure describe the push or the pull?
PULL; example: give Albumin it will PULL fluid into intravascular spacae
Does Hydrostatic Pressure describe the push or pull?
PUSH; example: blood pressure, perfusion pressure
What is Fick's Law? (Definition and Equation)
-The rate of transfer of a gas through a tissue is proportional to the tissue area and the difference in gas partial pressure between the two sides, and inversely proportional the thickness
Ficks Law= A X D X (P1-P2)
T
What is Graham's Law?
The rate of diffusion of a gas is inversely proportional to its molecular weight.
(larger something is the less it has the ability to diffuse)
(Light molecules travel faster, collide more frequently, and diffuse faster)
What is the equation for the Diffusion Constant?
What law(s) state "Diffusion is proportional to the tension gradient (aka partial pressure)"?
Fick's Law
What law(s) state "Solubility is related to partial pressure (aka tension gradient) and so also to diffusion rate"?
Henry's Law and Fick's Law
What law(s) state "Diffusion across a membrane depends on the membrane concerned (area and thickness)"?
Fick's Law
What law(s) state "Diffusion is affected by molecular weight"?
