Exam #2 Flashcards
define solubility
the maximum amount of one substance (solute) that is able to dissolve into another (solvent)
3 factors that affect solubility
intermolecular interactions
temperature
pressure
how do intermolecular interactions affect solubility
like dissolves like
polarity/ionization
similar electron configuration–> higher solubility
how does temperature affect solid/liquid solubility
elevated temperature increases solubility
how does pressure affect solubility
affects gases
higher pressure increases solubility
how does temperature affect the solubility of gases
inverse relationship
hypothermia– anes. gases stay soluble in blood rather than to lungs and being exhaled by the body as a gas
Henry’s law
What is the formula?
at constant temp, the amount of gas dissolved in liquid is directly proportional to the partial pressure of that gas at equilibrium above the gas-liquid interface
p=kc
(k-constant)
(c-concentration)
(p-partial pressure)
Graham’s law
the rate of effusion of a gas is inversely proportional to the square root of its molecular weight
smaller molecule-> faster diffusion
Fick’s law
diffusion of a gas is directly proportional to the partial pressure gradient, the membrane solubility of the gas, and the membrane area
diffusion of a gas is inversely proportional to the membrane thickness and the molecular weight of the gas
how does Fick’s law apply to anesthesia (4)
passive oxygenation (in ENT cases, unable to ventilate)
diffusion hypoxia
concentration effect
second gas effect
what is diffusion hypoxia
nitrous is very soluble
tissues become saturated, diffuse into alveoli quickly once turned off, creating hypoxic mixture in the lungs <21%
what is concentration effect
increasing the fraction of inspired concentration (FI) of an inhalation anesthetic will more rapidly increase the fraction of alveolar concentration (FA) of the agent– think about Henry’s law
what is second gas effect
As nitrous is diffused into the blood from the alveoli at a faster rate than the volatile anesthetic, it leaves a void of volume in the alveoli. It creates pressure gradient, allowing more volatile anesthetic to enter the alveoli at a faster rate.
plasmolysis
cells in hypertonic fluid
cytolysis
cells in hypotonic fluid
tonicity
the capacity of a solution to modify the volume of a cell by altering its water content
tonicity example in clinical practice
elevated ICP treated with an agent creating a hypertonic osmotic environment, pulling fluid from interstitial space around brain
Osmotic diuretic (mannitol) increases serum tonicity, drawing edema from brain parenchyma into the intravascular space
Bronsted-Lowry Acid
proton donor
Bronsted-Lowry Base
proton acceptor
Lewis Acid
electron pair acceptor (electrophile)
Lewis Base
electron pair donor (nucleophile)
define acid
substance that can donate a proton or accept an electron pair in a chemical reaction
define base
substance that can accept a proton or donate an electron pair in a chemical reaction
acid-base reaction
acid and a base react to form water and a salt (ionic compound)
acid+base->water+salt
define buffer and example
help regulate and stabilize pH
CO2+water <–> carbonic acid <–> HCO3+ H+
define pKa
pKa of a molecule represents the pH at which 50% of the molecules exist in the non-ionized and 50% in the ionized form
constant
define pH
quantifies the concentration of hydrogen ions in a solution
how does pKa relate to anesthesia?
injecting local anesthetic into inflamed, acidic tissue
doesn’t promote the breakdown of lidocaine HCL to lidocaine + H+
when lidocaine is not conjugated, it remains in an ionized, ineffective state
pH = pKa meaning
HA = A-
pH > pKa
A- > HA
pH < pKa
HA > A-
is pH a constant?
no, pH of blood can influence ionization of drug
define colligative properties
set of physical properties of a solution that depend solely on the number or concentration of solute particles in a solution, regardless of the identity of the solute particles.
These properties are primarily related to the behavior of a solvent when solute particles are added to it.
3 colligative properties
vapor pressure lowering
boiling point elevation
freezing point depression
molality equation
moles solute/ kg solvent
explain the colligative property of vapor pressure lowering
solute molecules get in the way from solvent going to gas phase
vapor pressure lowering equation
Psolution= Xsolvent * P°solvent
Psolution= new vapor pressure
Xsolvent= solvent particles/total particles
P°solvent= pure solvent vp
explain the colligative property of boiling point elevation
∆Tb=m(Kb)
m=molality
Kb=constant specific to solvent
explain the colligative property of freezing point depression
particles get in the way of lattice formation ex: salt on icy streets
∆Tf=m(Kf)
m=molality
Kf=constant specific to solvent
fluid flow=
pressure difference * resistance
SI unit for viscosity
Pa s (pascal seconds)
define viscosity
measure of a fluid’s resistance to flow and deformation by stress due to internal friction
viscosity affect on flow rate
increased viscosity leads to decreased flow rate
3 factors that affect viscosity
strength of intermolecular forces
size/shape of molecule
temperature
2 types of intermolecular forces
cohesive and adhesive
define cohesive forces
intermolecular forces b/w the molecules in a liquid
why are water molecules spherical
maximize hydrogen bonding by decreasing SA
molecules on the edge only half the effect of hydrogen bonding
define adhesive forces
interaction b/w the liquid and solid surface. Water will spread out on a surface if adhesive force>cohesive forces
concave meniscus is an example of what force
adhesive>cohesive
convex meniscus is an example of what force
cohesive>adhesive
layers of turbulent flow
laminar sublayer
buffer layer
turbulent boundary
3 types of flow
laminar
transitional
turbulent
define laminar flow
fluid flows steadily in one direction
which law calculates laminar flow rate
Poiseuille’s law
define turbulent flow
fluid swirls in eddies
which type of flow has higher velocity
turbulent
what is Reynold’s number
probability of turbulent rather than laminar flow
what is Reynold’s formula
Re= (ρuL)/μ
ρ= fluid density
u= fluid velocity
L= characteristic length
μ= dynamic velocity
Bernoilli’s law
increased velocity of fluid through pipe leads to decreased pressure on pipe’s walls
Bernoulli’s equation
P+1/2pv^2+pgy
P= pressure
p= density
v= velocity
g= gravity
y= height
(pressure+kinetic energy+potential energy)
define hydrostatics
characteristics of fluids at REST and the pressure in a fluid or exerted by a fluid on an immersed body
define hydrodynamics
MOTION of fluids and forces acting on solid bodies immersed in fluids and in motion relative to them
what effect is linked to Bernoulli’s princible
venturi effect
what is the venturi effect
a constriction in a pipe leads to faster velocity and lower pressure
how does the venturi effect relate to anesthesia
venturi mask- 100% O2 moving through small tube at high velocity, creating lower than atmospheric pressure leading to room air to enter through the hole on the green compartment
which forces in the Reynold’s formula favors turbulent flow
inertial forces: ρuL
which forces in the Reynold’s formula favors laminar flow
viscous forces: μ
how does Reynold’s number predict type of flow
Re<2000 is typically laminar
Re 2000-4000 is typically transitional
Re>4000 is typically turbulent
what type of flow is found in blood vessels
laminar
what may create turbulent flow in blood vessels
atherosclerosis
stenosis
aneurysm
define continuity equation
states the velocity of a fluid flowing through a pipe is INVERSELY PROPORTIONAL to the area of the pipe
for a given flow rate, fluid flows faster through thinner pipe
continuity equation
(A1)(v1)=(A2)(v2)
A= area
v= velocity
mass=
pV
(density*volume)
∆V=
(volume)
A(∆I)
(area*change in distance)
v=
(velocity)
∆I/∆t
I= distance
t= time
What is pulmonary surfactant
complex lipoprotein (DPPC) formed by type 2 pneumocytes lining the alveoli
what is frequency (wave motion)
the number of complete waves passing a fixed point in a given period of time
what is the symbol for frequency
f
what is the SI for frequency
hertz (Hz)
what is period (wave motion)
the time for one complete cycle to occur
what is the SI for period
second
what is wavelength (wave motion)
the distance from a point on one wave to the same point on the next wave
what is the SI for wavelength
meter
what is the symbol for wavelength
λ
lambda
what is amplitude wave motion)
the distance from the maximum disturbance to the undisturbed position
2 types of waves
longitudinal
transverse
what is a longitudinal wave
particles vibrate parallel to the direction the wave of energy is traveling
what is a transverse wave
particles vibrate perpendicular to the direction the wave is traveling
define rarefaction
area in longitudinal wave where the particles are far apart
define compression
area in longitudinal wave where the particles are close together
inverse square law
change in intensity due to the change in distance
ex: x-ray beam or flashlight
doppler effect
as source or observer travel closer, frequency detected by observer is higher than frequency emitted
as source or observer travel farther apart, frequency detected by observer is lower than frequency emitted
why does the doppler effect occur
as the source moves, the distance between sound waves in the direction it is moving decreases, leading to increased observed frequency
label this diagram
- amplitude
- wavelength
what is Poiseuille’s equation
Q=(π r^4 P) / 8 η L
L=length
η= viscosity
Q= flow rate
r= radius
P= pressure
what are the conditions that make Poiseuille’s law true
laminar flow
incompressible (density doesn’t change)
2 ways to increase flow during administration of IVF or blood products
administer in a line with a large radius
administer in a line with a shorter length
