Exam #1 Flashcards
Force
the amount of energy to move an object
Force = mass x acceleration
Pressure
force over area, increasing the area in which force is applied results in a lower pressure
P=f/a
Work
transfer of energy by a force acting on an object as it is displaced
W=Fs (force*displacement)
Energy
the capacity to do work or the exertion of force (potential +kinetic energy)
Power
amount of energy transferred or converted per unit time
P= force/velocity
Force SI units
newton
Pressure SI units
pascal (Pa)
Work SI units
joule
Energy SI units
joule
Power SI units
watt
Conduction
energy transfer between 2 objects in direct contact
Ex- touching a cold surface
Convection
air passing by aka wind chill
Body heat is lost to surrounding cold air. The surrounding air becomes warmer and rises; cool air falls and replaces the warm air (it’s a current/cycle).
Radiation
electromagnetic transfer of energy away from a warm body– biggest contributor
Evaporation
liquids on skin evaporate, utilizing energy to turn liquid to vapor
how to mitigate radiation in the OR
head is always perfused and major contributor to radiation heat loss, so it should be covered
how to mitigate convection in the OR
covering the patient with warm blankets forced air warming device
Close air vents to prevent a draft
how to mitigate conduction in the OR
preheat the OR table
Cover the table with blankets if possible
how to mitigate evaporation in the OR
HME, air humidifier on airway circuit
Be careful when scrubbing the surgical site with CHG, prep necessary sites only
Newton’s first law
objects have a tendency to maintain velocity unless acted on by unbalanced force
Law of inertia
Newton’s first law r/t anesthesia
blood loss-blood will have the tendency to maintain velocity, unless acted upon, such as clots or external pressure
Trauma- a gunshot will stay in motion unless acted upon, such as a skull.
Newton’s second law
F=m*a
Force= mass • acceleration
Newton’s second law r/t anesthesia
pressure bag for fluids
force=mass of fluid*velocity of fluid
Kelvin to celsius conversion
Celsius + 273.15= Kelvin
Newton’s third law
for every action, there is an equal and opposite reaction
Law of reciprocal action
Newton’s third law r/t anesthesia
heart failure cardiomegaly
low EF-> increased blood volume in LV to push out, but the blood also pushes on the cardiac muscle, stretching it out
CPR- the action of the RN pushing DOWN on the chest, reciprocal action- chest recoil
First law of thermodynamics
energy can’t be created or destroyed, only transferred (heat)
Law of conservation of energy
Second law of thermodynamics
no spontaneous transfer of heat from cold to hot
Energy moves towards greater entropy/randomness
temperature =
avg. KE
Average heat loss/gain of a system (think of ice melting in a cup of water)
KE equation
(m|v|^2)/2
PE equation
mgh (massgravity forceheight)
zeroth law of thermodynamics
systems in thermal equilibrium do not exchange energy in the form of heat
gravity force constant
9.81 m/s/s = 1 Newton
what is a pascal
1N/1m2
entropy
The equilibration of energy. Energy moves from high to low concentration to achieve equilibrium. The difference in the gradient influences the flow of energy.
fahrenheit to celsius
(f-32)/1.8
scalar values
magnitude only
distance
speed
vector values
magnitude and direction
displacement
velocity
how do surgical wounds contribute to heat loss?
convection
The open wound releases heat to warm up the surrounding cool air.
Biggest drop of heat loss in the perioperative phase
during the first 30-60mins of anesthesia
The adult body loses 1C.
what part of the brain is responsible for regulating temperature
hypothalamus
populations where shivering is detrimental
TTM
Shock
hypoxemic
Increases metabolic demand and o2 consumption
temp value indicating hypothermia
95F
35C
4 factors that affect rates of flow on IV fluids
pressure gradient
viscosity of fluid
length of tube
radius of tube
medications that cause vasodilation during anesthesia
Basically everything!!
volatile anesthetics
lidocaine
propofol
versed
fentanyl
hydralazine
dex (depends on dose)
how does neuraxial anesthesia cause decreased body temperature
brain doesn’t receive cold signal, thinks its warm
efferent nerves that control vasoconstriction and shivering are blocked
how does rapid NS infusion lead to hyperchloremic acidosis
^^chloride levels
bicarb doesn’t want to leave the cell d/t all the chloride
chloride can’t break down H+ to be excreted
acids build up
difference between accuracy and precision
accuracy- how close readings are to target
precision- how close readings are to each other
how can accuracy be improved
recalibration
maintain consistent experimental conditions
control external factors that can introduce variability
how can precision be improved
education on proper use of the device to use the device consistently
density
mass/volume
specific gravity
density of object/density of water
density of water in g/cm^3
1.06
density of water in lbs/ft^3
62.4
baricity
the ratio of the density of LA and CSF
How to determine the pH of a buffer
Henderson equation
pH = pKa + log10 ([A–]/[HA])
define anion gap
difference between measured serum cations and anions under normal conditions
anion gap formula
(Na+K)-(Cl+HCO3)
How to apply physics principles to traumatic brain injuries
coup and contrecoup lesions
brain will continue to move until acted up (the skill) damaging the opposite side of the brain from where the injury occurred.
How is the Periodic Table organized
It is organized by groups- vertical columns, and periods - horizontal rows. And it also has subgroups by elemental properties.
Covalent bonds
The physical sharing of electrons. can hold up to triple bonds. This tends to be bonding between atoms that share similar electronegativity.
Ion - Ion bond
The strongest electrostatic bond, occurs along the outer shell. Have the highest boiling and melting points.
Electrostatic bonds
The attraction of electrons between atoms due to electron distribution or electronegativity. This includes ion-ion, ion-dipole, and dipole-dipole interactions
Ion
Atoms that have gained or lost electrons from their natural composition. These atoms either have a positive or negative charge
Anion
Atom that has gained one or more electrons, is negatively charged.
Cation
An atom that has lost one or more electrons, is positively charged.
Isotopes
Same number of protons but different number of neutrons. This leads to a different mass number.
Ion dipole bond
A weak bond due to partial charges being involved. However, the molecule itself does not have a formal charge.
Isomers
Molecules that have the same chemical formula but different structures. Although the number and type of atoms and bonds are the same, the arrangement is different.