Chem and Phys Test 1 Flashcards
Perioperative Heat Loss Timeframe
The patient core temperature drops the most in the first hour of induction.
Due to impairment of vasoconstriction and shivering responses.
Temperature stops dropping once it reaches 34.5 C
General anesthesia and temperature
Vasoconstriction is reduced and heat in the core moves to the periphery allowing core temperature to drop to anesthetic induced lowered threshold for vasoconstriction. Core to peripheral heat redistribution causes 0.5-1.55C drop in core temperature in the first hour of anesthesia
Thermoregulatory Vasoconstriction
Maintains temperature gradient between the core and periphery between 2-4C. Core (head, chest, and, pelvis) is insulated from environment by peripheral compartment
Most significant process in which patients experience heat loss during anesthesia
Radiation; accounts for 60% of heat loss
Which type of heat loss occurs when skin is prepped Chloaprep
Evaporation: warm heat from body causes liquid skin prep to turn to vapor.
Evaporation
Process in which liquid is changed to gas; requires energy to break hydrogen bondsBreathing causes heat loss through exhaled water vapor. Decrease gas flow rates, use humidification with patient who are intubated.
Complications of Hypothermia ( <35C)
surgical site infection due to impaired vasoconstriction and decreased blood flow to area dehiscence bleeding due to impaired coagulation ventricular ectopy delayed drug metabolism increased length of hospital stay higher blood transfusion rates impaired host defenses thermal discomfort
Newton’s first law of motion
A body at rest or moving at a constant speed in a straight line will remain at rest or continue in a straight line at a constant speed unless it is acted upon by a force
Newton’s second law of motion
Force = mass x acceleration
The rate of change of momentum of an object is directly proportional to the momentum of the force applied.
Newton’s third law of motion
Every action has an equal and opposite reaction
When one object exerts a force on a second object, the second object exerts a force that is equal in magnitude and opposite in direction
Heat loss
Transfer of energy from a higher concentration of the a lower concentration
Radiation
Charged particles are accelerated and release electromagnetic wavelengths. Heat is then transferred from body to cooler environment. Vasodilation effect of anesthesia causes increased blood flow from body’s core to periphery. Cover body surfaces not being operated on lessens heat loss.
Convection
Heat has higher kinetic energy and rises due to less density. Cold air lower energy molecules due to greater density. As heat rises from body, colder molecules fall and are heated by the body’s warmth; creating air currents. Heat is lost from the body and air is warmed. Decrease the temperature in the room.
Conduction
Heat is transferred from warmer object physically touching cooler object. Ex: warm patient body on cool OR table. Place warm blankets on OR table.
Standard measure of force
Newton; kg*meter/second^2
average gravity on Earth
9.80665 m/s^2
1 newton
force of 100,000 dynes, Ex: SVR, PVR measurement
Vectors
magnitude and direction displacement: distance with direction velocity: speed with direction acceleration: how quickly speed changes force
Scalars
magnitude only; volume density speed mass time temperature distance work pressure
Resultant
addition of 2 vectors; must take into account value and direction
Velocity
displacement/time, 0 if end at the same location
meter/sec
Work
Work = force x distance (or displacement)
Amount of energy necessary to move an object from one point to another
If work is done on you –> you gain heat
If you do work on something –> you lose heat
Unit: Joule = kg* m^2 / s^-2
(no change in volume/energy/distance = no work done)
penetrating injury damage depend on what 3 factors
- type of wounding instrument (knife, missile (bullet or fragment)
- velocity of the missile at time of impact
- characteristics of tissue which it passes (bone, fat, muscle, blood vessels, nervous tissue, organs)
Lower velocity wounds
inflict injury by lacerating and cutting tissue.
Moderate to high velocity wounds
result from deceleration of object as it passes through tissue, causing kinetic energy to transfer to surrounding tissue.
Most significant determinant of wound potential
velocity; bullet wounds have greater potential to inflict serious injury compared with a knife of handheld projectile
speed
distance traveled/time elapsed; m/s, mph
rate at which something moves of changes position
Blunt trauma injuries
Fractures, lacerations, external wounds, tearing by shearing forces, coup-contrecoup injuries
Pressure units
force/area; Pascal (Pa) = N/m^2
Gauge pressure
Pressure of a system above or below atmospheric pressure
Gauge pressure = total pressure -atmospheric pressure
0 reference point
1KPa
1000 Pa (Pascals)
1atm
101.3KPa
Second law of thermodynamics
Heat naturally flows from hot to cold; the only way for cold to flow to hot is via the addition of energy
Ex: Ball naturally flows from high position to low position at the top of a hill, but the ball cannot naturally go back up the hill
Change in entropy is > 0
Entropy
Natural processes move toward disorder; universal trend toward equilibrium; unidirectional
Low energy = energy concentrated
High energy = more spread out energy
Force
Push or pull required to produce an acceleration
Newtons or N
Kinetic Energy
Ability to do work; energy of motion
KE = 1/2 mv^2 (mass * speed)
Power
Rate at which energy is spent; rate of doing work
Power = work/time
Unit: Watts (W) = Joule/second
Syringe size and pressure
Syringe is an example of pressure generated by force over area
Pressure = force/area
Increase area over which same force is generated, decease pressure
Decrease area over which same force is generated, increase pressure
Barometer
tube closed at one end and open on the other; pressure of the atmosphere and the weight of mercury column = opposing forces. More air pressure = more force = increased height of mercury
P(atm) = density x gravity x height (pgh)
* Measure actual or absolute pressure
Total pressure = gauge pressure + atmospheric pressure
Manometer
U-shaped tube filled with a fluid of a known density; measures pressure difference
delta P = P (system) - P (atmosphere)
* measure gauge pressure
Bourdon Gauge
Used on gas cylinders; type of aneroid gauge bc they don’t use liquid.
Measure pressure difference btw pressure exerted by gas on cylinder and atmospheric pressure. Gas above atmospheric pressure enters coiled tube –> slight uncoil and pointer moves to show gauge pressure
*Measure gauge pressure
1 pascal
N/m2
Potential energy
stored energy
PE = mass * gravity * height
Ex: battery, plane in the air, chemical energy stored in food
Internal energy
kinetic energy + potential energy
First Law of Thermodynamics
Law of conservation of energy; energy cannot be created or destroyed
Third Law of Thermodynamics
Absolute; is considered void of energy, theoretically impossible to reach
Mass
Amount of matter in an object; resistance of an object to acceleration
Unit: Kg
Enthalpy
Total amount of energy in a system
Metric system Units
Length: meters
Mass: Kilograms
Temperature: Kelvin
Mole (mol): measures amount of material
Acceleration
Rate at which velocity changes
Speeding up, slowing down, changing direction
Average acceleration = delta velocity/delta time
Units: m/s^2
Weight
gravitational force exerted on an object by a much larger object
Unit: N
Weight (N) = mass (kg) x gravitational force (6.8m/s2)
giga
10^9
mega
10^6
kilo
10^3
deci
10^-1
centi
10^-2
milli
10^-3
micro
10^-6
nano
10^-9
Accuracy
The agreement between experimental data and the true/expected value (within a margin of error)
Assessed via % error calculation
% error: [(measured value-true value)/(true value)] x 100
Precision
Agreement between replicate measurements (over and over again yields the same result)
Standard deviation assesses precision
Smaller the ratio of the standard deviation to average value, the better the precision
Greater number of significant figures implies greater precision
Most accurate core temp location in adults
Temporal artery; high ease of access and accuracy
Density
represented by d or p (rho)
Density = mass / volume
Density will also have 2 units
Density of water = 1.0g/mL
Specific gravity
Ratio between an object’s density and the density of water
SG = density of object / density of water
SG is dimensionless
Specific Gravity and temperature
Can decrease specific gravity by increasing temp of the substance.
Increasing temp expands the volume (increases the volume) –> decreased density
CSF example:
Med injected that has higher specific gravity than CSF will sink
Med injected that has lower specific gravity than CSF will float
Sample with specific gravity greater than 1 is denser than water and will sink
Sample with specific gravity less than 1 is less dense than water and will float
Ion
molecule/atom that have net electric charge; either gained or lost electrons
* positive or negative charge
Cation
atom that has lost an electron
positive charge
Anion
atom that has gained an electron
negative charge
Organic ions vs inorganic ion
Organic ions: contain carbon Ex: Phosphate intracellularly (ATP) Can be lowered by diuretics Inorganic: do not contain carbon Ex: Phosphate extracellularly
Significant figures
Digits in a measured value that have physical meaning and can be reproductively determined
Nonzero digits are always significant
Captive zeros are always significant
Leading zeros are never significant
Trailing zeros are only significant when the number contains a decimal point
When adding/subtracting: keep smaller number of decimal places and round
When multiplying/dividing: keep smaller number of significant figures and round
Matter
anything that has mass and takes up space
Atoms
building blocks of matter, have 3 particles
Protons: positively charged with a mass of 1 amu
Neutrons: electrically neutral and have a mass of 1 amu
Electrons: negatively charged, smaller mass than protons and neutrons
Elements
contain only a single type of atom; always electrically neutral, so each atom must have an equal number of protons and electrons
Compounds
contain 2 or more kinds of atoms
Molecules: group of atoms chemically bonded together into unit by covalent bonds, electrically neutral
Ions: positively or negatively charged ions; have no identifiable discrete units
Pure substances
cannot be physically separated into simpler components. mostly metals, nonmetals, and metalloids
Ex: steel, iron, gold, copper
Mixtures
comprised of 2+ substances and can be separated into smaller components through physical process
Homogeneous: uniform in chemical and physical properties. Ex: blood, wine, coffee, air
Heterogeneous: not uniform between component. Ex: emesis, salad
Atomic number
Number of protons in the nucleus
Determines identity of atom
Mass number
sum of atomic number and neutron number
Neutron number
Mass number - atomic number
Isotopes
have the same atomic number but different mass number; same number of protons, different number of neutrons
Order of elements
Elements are listed in order of increasing atomic number, each successive element has one additional proton
Vertical columns (groups/families)
Elements in each group have similar chemical and physical properties
Rows (Periods)
Periods represent adding electrons to quantum energy levels in the atom
Classifying elements on periodic table
Representative elements have a group number with an A
Transition elements have a B designation in their group #
Inner transition elements are located at the bottom of table
Chemical nomenclature
Determine of metal or nonmetal
Molecular compounds are comprised of nonmetals
Ionic compounds are almost always comprised of a metal and a nonmetal
Naming molecular compounds
Name each element
Indicate how many of each element is present with prefix multiplier (mono, di, tri, tetra, penta, hexa, hepta, octa)
Add suffix “-ide”
Dihydrogen monoxide (H2O)
Naming ions and compounds
Ion is an atom or group of atoms with a charge
Ionic compounds have ions and are held together by ionic bonds
Monatomic cations of metals
Representative metals form cations where ionic charge equals the group number; group number equals # of electrons in outer shell; gives away electrons to fill shell
Name the element and add ion or cation
Na1+ = sodium ion
Monatomic anions of nonmetals
Representative nonmetals: ionic charge is based on number of electrons the nonmetal needs to gain in order to fill shell
Name the element and add suffix “ide”
Cl 1- = Chloride ion
Transition metals: Cations
If transition metal forms only one cation, name like representative cation
If transition metal forms more than one cation, name metal and indicate charge on the cation with Roman numerals in parenthesis
Fe 2+: Iron (II) ion
Polyatomic ions
Formed from 2+ nonmetals that are bonded together in a way that results in net electrical charge
Ion with larger number of oxygen atoms is given “ate”,
Ion with smaller number of atoms oxygen is given “ite”
SO4 2-: sulfate
SO3 2-: sulfite
Electrolytes
Substance that dissolves in water to give a solution that conducts electricity
The few ionic compounds that readily dissolve in water are electrolytes because they separate into ions that freely and independently move around in the solution; free movement –> electricity conduction
Molecular compounds are nonelectrolytes, unless they have acid or base properties
Tap water conducts electricity because it contains a fair concentration of electrolytes
Pure water is a non electrolyte and does not conduct electricity
Reduction
Gain of electron
Oxidation
Loss of electron
Hydrolysis
Use of water to split molecular bonds H-R-R-OH + H-OH -> 1 large molecule is broken up into 2 smaller molecules H-R-OH and H-R-OH Ex: Polymer to monomer Starch + H2O = Glucose + Glucose Polypeptide + H2O = Amino acid
Amino Acids
DNA –> (transcription) mRNA -> (translation) - tRNA + amino acids -> protein formation
Proteins = chain of amino acids
Amino group + Carboxyl group + Alpha carbon + R group
Lipids
Partly hydrophobic; partly hydrophilic
Function: energy storage, signaling, membrane structure
Hydrophilic head; hydrophobic chain
Proteins
Building block = amino acid
Amino acids connected by peptide bonds
Primary structure: sequence of amino acids in peptide chain
Secondary structure: how amino acid chain twists on itself. Hydrogen bonds btw H and N form bond btw carbonyl.
Ex: alpha helix coil stabilized by hydrogen bonds. Common in wool
Ex: beta pleated sheet -> nearby linear strands of polypeptide chains line up in linear fashion. Common in silk
Tertiary Structure: how polypeptide chain folds to form globular structure. Hydrogen bonding and London forces.
Carbohydrates
1 Oxygen:2 Carbon ration Building block is glucose Glucose = monosaccharide Glucose chain = polysaccharide Energy store
Phase 1 metabolism
Uses enzymes (oxidases) to unmask polar groups (-OH and -O’s) on the drug
Drug + O2 + NADPH –> Drug-O + H20 + NADP+
NADPH acts as reducing agent
Mainly uses cytochrome p450 to produce result
* Requires oxygen
CYP3A4: metabolizes > 50% of drugs
CYP2D6: famous for polymorphisms
Phase 2 metabolism- Conjugation reaction
Uses enzymes (transferases) to transfer small endogenous polar molecules onto a drug to make it more water soluble.
UGT: UDP-glucuronsyltransferase -> glucuronidation
GST:Glutathione conjugation
NAT: Acetylation
SULT: Sulfation
Oxygen NOT required
Krebs cycle
Glycolysis of glucose (6 carbon) -> 2 pyruvic acids (2 3-carbon) -> 2 net ATP + 2 NADH ->
Acetyl CoA in prep for Krebs cycle
Acetyl CoA merges w/ Oxoloacetic acid -> citric acid
Citric acid -> oxidized to Oxoloacetic acid -> 6x CO2 + 10 NADH + 4 ATP + 2 FADH2
10 NADH -> oxidized in electron transport chain -> 30 ATP
2 FADH2 -> oxidized in electron transport chain -> 4 ATP
4 + 4 + 30 = 38 total ATP
Glycolysis occurs in cytoplasm
Krebs cycle occurs in mitochondria
Catabolic reaction: breakdown of glucose to make ATP
Acetyl CoA: general catabolic intermediary that enters Krebs cycle to create ATP via glucose, protein, fat metabolism
Polar molecules
Hydrophilic; partial or full charge
DNA
Sugar backbone is composed of deoxyribose
Bases: thymine, adenine, guanine, cytosine
RNA
Sugar backbone is composed of ribose
Bases: uracil, adinine, guanine, cytosine
3 ways to denature protein
Heat, heavy metal ions (Ag+, Hg2+)
Monosaccharides
Glucose, fructose, galactose
Disaccharides
Sucrose, Lactose, Maltose
Polysaccharides
Starch, Glycogen, Cellulose
3 ways to denature protein
Heat
Heavy metal ions (Ag+, Hg2+)
Changes in pH
Monosaccharides
1 sugar
Glucose, fructose, galactose
Disaccharides
2 sugars
Sucrose, Lactose, Maltose
Polysaccharides
Complex sugar
Starch, Glycogen, Cellulose
Saturated alkane formula
C(n)H(2n+2)
Phosphate esters
DNA & RNA backbone
