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Review Apex > UNIT 12 Miscellaneous Topics > Flashcards

UNIT 12 Miscellaneous Topics Flashcards

1
Q

describe the architecture of an atom

A

basic building block that makes up all matter. Consists of 3 components

  • protons (+ charge)
  • neutrons (no charge)
  • electrons (- charge)

protons/neutrons at the center of the atom, together forming the nucleus
- number of protons = atomic number

electrons orbit the outer nucleus in the e- cloud
- they are attracted to the positive nucleus, keeping them from flying away

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2
Q

how do you know if an atom carries a charge? what is a charged atom called?

A

neutral: electrons = protons
positive: protons > electrons
negative: electrons > protons

ion = atom that carries a positive or negative charge.

    • charge: cation
    • charge: anion
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3
Q

what is an ionic bond?

A

complete transfer of valence electrons from one atom to another, leaving one atom w/ a negative charge and the other w/ a positive charge

metals tend to form ionic bonds
- also common w/ acids and bases

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4
Q

what is a covalent bond?

A

equal sharing of electrons. This is the strongest type of bond

  • single bond = 1 pair e- is shared
  • double bond = 2 pairs
  • triple bond = 3 pairs
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5
Q

what is a polar covalent bond?

A

polar covalent bonds are an “in-between” type of bond

atoms share electrons but the electrons tend to remain closer to one atom than the other. This creates a polar molecule, where one area of the molecule is relatively positive and the other is relatively negative

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6
Q

what are van der Waals forces?

A

very weak intermolecular force that holds molecules of the same type together

electrons are in constant motion, creating a temporary + and - charges at different parts of the molecule at any given time. The net result is that electron rich areas of one molecule will be attracted to electron poor areas of another molecule.

This is the weakest type of molecular attraction

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7
Q

define Dalton’s law. list several examples of how it can be used in the OR.

A

daltons law of partial pressures says that total pressure is equal to the sum of the partial pressures exerted by each gas in the mixture.

Ptotal = P1 + P2 + P3 + ..

applications:
- calculate partial pressure of unmeasured gas
- calculate total pressure
- convert partial pressure to volumes percent
- convert volumes percent to partial pressure

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8
Q

at sea level, the agent monitor measures the end tidal sevo as 3%. What is the partial pressure of sevo in the exhaled Tv?

A

application of Dalton’s law of partial pressures

PP = volumes % x total pressure

0.03 x 760mmHg = 22.8mmHg

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9
Q

define Henry’s law. List several examples of how it can be used in the OR.

A

at constant temp, the amount of gas that dissolves in solution is directly proportional to the partial pressure of the gas over the solution. (the higher the gas pressure, the more that will dissolve into a liquid)

increase temp = decrease solubility
decrease temp = increase solubility

applications:
- anesthetic emergence is prolonged in the hypothermic patient
- dissolved oxygen in the oxygen carrying capacity equation (CaO2)

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10
Q

describe Fick’s law of diffusion.

A

transfer rate of gas through a tissue medium.

rate of transfer increases w/:

  • partial pressure difference
  • diffusion coefficient
  • membrane surface area

rate of transfer decreases w/

  • membrane thickness
  • molecular weight
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11
Q

list clinical examples of Fick’s law of diffusion.

A 
diffusion hypoxia
COPD = reduced alveolar SA
- slower rate of inhalation induction
CO calculation
drug transfer across placenta
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12
Q

compare and contrast Boyle’s, Charles, and Gay-Lussac’s laws.

A

Boyle
P1V1=P2V2

Charles
V1/T1=V2/T2

Gay-Lussac
P1/T1=P2/T2

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13
Q

list several examples of how Boyle’s law can be applied in the OR.

A

(PV)

  • diaphragm contraction increases Tv
  • pneumatic bellows
  • squeezing an Ambu bag
  • using Bourdon pressure gauge to calculate how much O2 is left in a cylinder
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14
Q

list an example of how Charle’s law can be applied in the OR

A

V/T

  • LMA cuff ruptures when placed in an autoclave
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15
Q

list an example of how Gay-Lussac’s law can be applied in the OR.

A

P/T

  • oxygen tank explodes in heated environment
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16
Q

what is the function of the ideal gas law

A

unifies all 3 gas laws into a single equation

PV= nRT

R = constant 0.0821 Latm/Kmol

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17
Q

define Ohm’s law

A

the current passing through a conductor is directly proportional to the voltage and inversely proportional to the resistance

we can adapt Ohm’s law to understand fluid flow

current = voltage difference/resistance

flow = pressure gradient/resistance

Q = change in pressure/R

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18
Q

how is Poiseuille’s law related to Ohm’s law?

A

Poiseuille’s law is a modification of Ohms law that incorporates vessel diameter, viscosity, and tube length.

Q = blood flow
R = radius
deltaP = arteriovenous pressure gradient
"n" = viscosity
L = length of the tube

Q = (piR^4deltaP)/(8”n”L)

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19
Q

how do changes in radius affect laminar flow (x2, x3, x4, adn x5)

A

altering the radius of the tube exhibits the greatest impact on flow

R = 1^4 = 1
R = 2^4 = 16
R = 3^4 = 81
R = 4^4 = 256
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20
Q

how can we apply Poiseuille’s law to the administration of a unit of PRBCs?

A

we can deliver PRBCs faster if we:

  • increase the radius w/ a large bore IV
  • increase the pressure gradient w/ a pressure bag or increasing IV pole height
  • decrease viscosity by diluting blood w/ NS or running it through a fluid warmer
  • decrease the length by not using longer tubing than you really need.
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21
Q

What does Reynold’s number tell you?

A

There are three types of flow: laminar, turbulent, and transitional

Reynolds number allows us to predict the type of flow that will occur in a given situation

Re <2000 = laminar flow is dependent on gas viscosity (Poiseuille’s Law)

Re 2000-4000 = transitional flow

Re >4000 = turbulent flow is dependent on gas density (Graham’s law)

Re = (densitydiametervelocity)/viscosity

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22
Q

explain how understanding Reynold’s number helps you treat status asthmaticus.

A

increased airway resistance, and this increases flow turbulence and the work of breathing.

  • bc turbulent flow is primarily dependent on gas density, we can improve flow by having the patient inhale a lower density gas
  • an oxygen/helium mixture (Heliox) improves Reynold’s number by reducing density
  • the key here is that we are converting turbulent flow to laminar flow. Helium doesn’t improve flow if it’s already laminar.
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23
Q

Explain Bernoulli’s principal, and discuss it in there context of a river.

A

describes the relationship b/n the pressure and velocity of a moving fluid (or gas)
- if the fluid’s velocity is high, then the pressure exerted on the walls of the tube will be low and vice versa

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24
Q

explain the Venturi effect, and give some examples.

A

an application of the Bernoulli principal. As air flow in a tube moves past the point of constriction, the pressure at the constriction decreases , and if the pressure inside teh tube falls below atmospheric pressure, then air is entrained into the tube (venturi effect)

adjusting the diameter of teh constriction allows for control of the pressure drop and the amount of air that is sucked into the tube. The key here is air entrainment!

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25
Q

explain teh Coanda effect and give some examples.

A

describes how a jet flow attaches itself to a nearby surface and continues to flow along that surface even when the surface curves away from the initial jet direction

ex: wall hugging jet of mitral regurg adn the water that follows the curve of a glass.

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26
Q

how do you calculate the law of Laplace for a sphere? for a cylinder?

A

sphere:
T = PR/2
ex: alveolus, ventricle, saccular aneurysm

cylinder
T = PR
ex: blood vessels, aortic aneurysm

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27
Q

what is the yearly maximum for radiation exposure? How does this change if someone is pregnant?

A

nonpregnant:
- 5rem max
- eye, thyroid = most susceptible

pregnant

  • 0.5rem max for fetus or 0.05rem/month
  • fetus = most susceptible
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28
Q

list 3 ways to protect yourself from radiation exposure

A

distance
duration
shielding

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29
Q

how can we apply the inverse square law to radiation exposure?

A

intensity of exposure

1/distance ^2

minimum safe distance from radiation source is 6ft

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30
Q

what is boiling point and how is it affected by atmospheric pressure?

A

BP = temp at which a liquids vapor pressure equals atmospheric pressure

increase in P –> increase BP (ex. hyperbaric O2 chamber)

decrease in P –> decrease in BP (ex high altitude)

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31
Q

define specific heat

A

amount of heat required to increase the temperature of 1g of a substance by 1C

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32
Q

define vapor pressure

A

in a closed container, molecules from a volatile liquid escape the liquid phase and enter the gas phase. The molecules in the gas phase exert a pressure on the walls of the container; this is vapor pressure

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33
Q

define vaporization

A

the process by which a liquid is converted to a gas (requires energy (heat))

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34
Q

define the heat of vaporization

A

the number of calories required to vaporize 1mL of liquid

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35
Q

explain latent heat of vaporization, and apply this to anesthetic vapor inside of a vaporizer

A

the number of calories required to convert 1g of liquid WITHOUT a temperature change in the liquid

applied to anesthetic vaporizer:
- gas exerts vapor pressure inside chamber
- FGF over liquid, carrying away some of the agent that exists in the gas phase
- this cools the remaining liquid –> reduction in VP of that liquid –> less molecules in the gas phase
NET RESULT: decrease in vaporizer output

However, modern vaporizers compensate for this temperature change

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36
Q

explain the Joule Thompson effect in the context of gas cylinders

A

gas stored at high pressure that is suddenly released escapes from its container into a vacuum. It quickly loses speed as well as kinetic energy –> decrease in temp

This explains why an oxygen cylinder that is opened quickly feels cool to the touch. Conversely, rapid compression of a gas intensifies its KE, causing temp to rise

REMEMBER: JOULE IS COOL

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37
Q

what is an adiabatic process?

A

process that occurs w/out gain or loss of energy (heat). For example, a very rapid expansion or compression of a gas where there is no transfer of energy is an example of an adiabatic process.

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38
Q

What is critical temperature, and how does this apply to gas cylinders?

A

critical temp = highest temp where a gas can exist as a liquid (i.e. it cannot be liquified regardless of pressure)

critical temp for N2O = 36.5, which explains why it’s primarily a liquid inside the cylinder.
critical temp for O2 = -119, so it exists as a gas inside the cylinder

of the gases used in the OR, only CO2 and O2 have critical temps below room temp

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39
Q

what is critical pressure?

A

the minimum pressure required to convert a gas to a liquid at its critical temperature

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40
Q

know the temperature conversion formulas.

A 
C = K - 273.15
K = C + 273.15
C = (F-32) x 5/9
F = (C*1.8) + 32
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41
Q

define pressure

A

pressure = force/area

increased area = decreased pressure and vice versa

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42
Q

know the pressure conversion factors

A

1 atm = 760mmHg = 760 torr = 1 bar = 1033 cmH2O = 14.7lb/in^2

1mmHg = 1.36cmH2O

1cmH2O = 0.74mmHg

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43
Q

what is avogadro’s number

A

says that 1 mole of any gas is made up of 6.023x10^23 atoms

  • a mole of gas is equal to the molecular weight of that gas in grams
  • if a molecule is diatomic (O2), you must account for both atoms
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44
Q

what are the 4 mechanisms of heat transfer? rank them from most to least important.

A

radiation - infrared (60%)
convection - air (15-30%)
evaporation - water (20%)
conduction - contact (<5%)

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45
Q

explain the 3 stages of intraoperative heat transfer

A

when no attempts are made to maintain normothermia, heat transfer follows a triphasic curve:

phase 1: heat redistribution from core to periphery

phase 2: heat transfer > heat production

phase 3: head transfer = heat production

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46
Q

what are the consequences of perioperative hypothermia?

A

CV:

  • SNS stimulation (MI, dysrhythmias)
  • O2Hgb curve L shift (decreased O2 delivery)
  • vasoconstriction, decreased tissue pO2 (SSI)
  • coagulopathy, platelet dysfunction (increased EBL)
  • sickling of HgbS (crisis risk)

pharm:
- slowed drug metabolism (prolonged effects of anesthetic agents)
- increased solubility of IA (prolonged emergence)

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47
Q

name 3 drugs that can be used to treat postoperative shivering.

A

shivering increases o2 consumption up to 400-500%. This increases the risk of MI and ischemia

  • meperidine (kappa)
  • clonidine (alpha2)
  • precedex (alpha2)
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48
Q

when is hypothermia a good thing?

A

all are based on the fact that O2 consumption is reduced by 5-7% for every 1C decrease in body temperature:

  • cerebral ischemia
  • cerebral aneurysm clipping
  • TBI
  • CPB
  • cardiac arrest
  • aortic cross clamping
  • carotid endarterectomy
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49
Q

in which region of the esophagus should an esophageal temp probe be placed? How does misplacement affect the reading?

A

in the distal 1/3-1/4th of the esophagus (38-42cm past the incisors)

temp is increased if placed in stomach d/t heat created by liver metabolism

temp is decreased if placed proximally d/t cool inspiratory gas.

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50
Q

compare and contrast the various sites of temp measurement.

A

esophagus: best in distal 1/3-1/4th of esophagus
nasopharynx: less reliable than esophageal
rectum: risk of bowel perforation
bladder: risk of UTI, decreased reading if inadequate UOP

pulmonary artery: temp decreased if open chest procedure

tympanic membrane: risk of tympanic membrane injury

skin: doesn’t correlate w/ core temp

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51
Q

what are the 3 ingredients required to produce a fire? Give examples of each

A

fuel (ETT, drapes, surgical supplies)

oxider (O2, N2O)

ignition source (electrosurgical cautery, laser)

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52
Q

details the steps you would take during an airway fire.

A 
stop ventilation, remove ETT
stop all FGF
remove other inflammable materials
pour water/saline in airway
\+/- CO2 fire extinguisher

after fire is controlled:

  • BMV, avoid supp O2 or N2O
  • check ETT for damage (fragments in airway)
  • bronch to inspect for a/w injury

DO NOT squeeze the reservoir bag as you extubate the patient (blow torch effect!)

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53
Q

what does laser stand for? how is it different from ordinary light?

A

light amplification by stimulated emission of radiation.

differs from ordinary light because it is:

  • monochromatic (single wavelength)
  • coherent (oscillates in the same phase)
  • collimated (exists as a narrow parallel beam)
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54
Q

what is the difference b/n a long and short wavelength laser? What are the clinical consequences of this?

A

long wavelength: absorb more water and don’t penetrate deep into tissue
- cornea is at risk

short wavelength: absorb less water and penetrate deeper tissues
- retina is at risk

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55
Q

what color googles must be worn for each type of laser: CO2, Nd:YAG, Ruby, and Argon?

A 
CO2 = Clear
Ruby = Red
Argon = Amber
Nd:YAG = Green
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56
Q

discuss the flammability of ETT in the context of laser surgery on the airway.

A
  • most ETT are flammable
  • laser reflective tape no longer advised (use laser resistance ETT)
  • laser resistant ETT are NOT laser proof
  • cuff is most vulnerable part
  • laser resistant tubes do NOT have laser resistant cuffs
  • fill cuff w/ saline/dye
  • many laser resistant ETT have 2 cuffs to allow for continued PPV in the event of perforation by the laser
  • laser resistant ETT doesn’t prevent fire w/ electrocautery
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57
Q

describe the 4 degrees of burns. Which require a skin graft?

A 
1st = epidermis (spont healing)
2nd = superficial dermis (spont healing) to deep dermis (skin graft)
3rd = subQ (skin graft)
4th = muscle/bone (skin graft)
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58
Q

describe the rule of 9s. How does this apply to the adult?

A

TBSA of a burn

9% head
36% torso
9% each arm
18% each leg
1% peri-area
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59
Q

how is the rule of 9s different for children?

A

head = 18% of TBSA

- legs are 15% each instead

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60
Q

describe the consequences of the capillary leak that occurs after a burn.

A

immediately after a burn, microvascular permeability increases –> capillary leak

  • edema
  • protein loss = decreased plasma oncotic pressure = edema
  • hypovolemia, shock
  • hemoconcentration

fluid shifts/edema are greatest in first 12hrs, begin to stabilize by 24hrs

  • avoid albumin in first 24hrs
  • hemolysis common but hypovolemia –> hemoconcentration (rise in Hgb in first few days = inadequate volume resuscitation)
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61
Q

Describe the parkland formula for resuscitation in burn patients.

A

1st 24hrs:

  • crystalloid = 4mL LR/% TBSA/kg
  • 1/2 in 1st 8hrs, 1/4 in 2nd 8hrs, 1/4 in 3rd 8hrs
  • no colloid

2nd 24hrs:

  • cystalloid = D5W at normal maintenance rate
  • colloid = 0.5mL/%TBSA/kg
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62
Q

describe the Modified Brooke formula for resuscitation in burn patients.

A

same as parkland except w/ 2mL LR/% TBSA/kg in first 24hrs

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63
Q

what is an acceptable UOP in a burned patient? Is this different in children or patients who’ve suffered a high voltage electrical injury?

A

adult > 0.5mL/kg/hr
child > 1mL/kg/hr
high voltage electrical > 1-1.5mL/kg/hr
- increased UOP d/t myoglobinemia from muscle damage after high voltage electrical injury (nephrotoxic)

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64
Q

why is the burn patient at risk for abdominal compartment syndrome? What is the diagnosis and treatment of this complication?

A

may be d/t aggressive fluid resuscitation

  • intra-abdominal HTN: IAP > 20mmH2O or >12mmHg AND evidence of organ dsyfunction
  • tx: NMB, sedation, diuresis, abdominal decompression via laparotomy
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65
Q

discuss the clinical considerations for the patient w/ CO poisoning.

A

CO binds Hgb 200x affinity of O2
COHgb = L shift OxyHgb curve
impairs oxidative phosphorylation
–> inadequate o2 delivery and utilization = metabolic acidosis

blood = cherry red
pulse ox = not accurate (may be falsely elevated)

tx: 100% FiO2, hyperbaric O2

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66
Q

discuss the use of NMB in burn patients.

A

upregulation of extrajunctional receptors begins after 24hrs

  • sux ok w/in first 24hrs post-burn
  • avoid sux after 24hrs (letahl hyperK+)
  • dose of NDMR should be increased 2-3x (there are more receptors)
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67
Q

describe the physiologic changes that accompany electroconvulsive therapy.

A

seizure caused by ECT causes profound physiologic changes:

  • initial: increased PNS during tonic phase (15sec) –> brady, hypotension, increased secretions
  • secondary: increased SNS during clonic phase (several mins) –> tachy, HTN, increased intragastric pressure, increased CBF, ICP, IOP
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68
Q

discuss the absolute and relative contraindications to ECT.

A

typically r/t increased SNS response or increased ICP.

absolute:
- recent MI
- recent intracranial surgery
- recent CVA
- brain tumor
- unstable C-spine
- pheo

relative

  • pregnancy
  • pacemaker/ICD
  • CHF
  • glaucoma, retinal detach
  • severe pulm disease
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69
Q

compare and contrast neuroleptic malignant syndrome w/ malignant hyperthermia.

A

NMS is d/t dopamine depletion in the basal ganglia and hypothalamus

  • causes: dopamine antagonists or withdraw from dopamine agonists
  • tx: bromocriptine, dantrolene, supportive care, ECT

compare/contrasting the two:

  • NMS no genetic link
  • NMS doesn’t develop acutely
  • NMS is associated w/ psych meds
  • both cause muscle rigidity, hyperthermia, tachycardia, acidosis
  • both can be treated w/ dantrolene
  • NMB cause paralysis in NMS but doesn’t in MH
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70
Q

what is the etiology and treatment of serotonin syndrome?

A

occurs when there is excess 5-HT activity in the CNS and PNS. Key drug interactions that increase the risk are:

SSRIs and:

  • meperidine
  • fentanyl
  • methylene blue

MAOI and:

  • meperidine
  • ephedrine.
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71
Q

what are the determinants of IOP? Whats the normal value?

A

intraoc perfusion pressure = MAP - IOP

globe is relatively noncompliant, thus the IOP is determined by the choroidal blood voulme, aqueous fluid volume, and extraocular muscle tone

normal = 10-20mmHg

aqueous humor is produced by the ciliary process (posterior chamber) and reabsorbed by the canal of Schlemm (anterior chamber)

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72
Q

what factors reduce IOP? which increase it?

A

decreases:
- hypocarbia
- decreased CVP, BP
- IA, N2O, NDMR, propofol, opioids, benzos
- hypothermia

increases:
- hypercarbia
- increased CVP, BP
- hypoxemia
- DL/intubation, straining/coughing
- succ, N2O if SF6 bubble
- trendelenburg, prone
- external compression by mask

LMA placement/removal = minimal effect on IOP
- ketamine +/- increases IOP, but causes nystagmus + blepharospasm (avoid in eye surgery)

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73
Q

what is the difference b/n open and closed angle glaucoma?

A

glaucoma is d/t chronically elevated IOP that leads to retinal artery compression.

open angle = d/t sclerosis of the trabecular meshwork, impairing humor drainage

closed angle = d/t closure of the anterior chamber creating mechanical outflow obstruction

IOP is decreased by drugs taht decrease aqueous humor production or facilitate drainage (cause miosis)

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74
Q

which drugs reduce aqueous humor production? which increase aqueous humor drainage?

A

aqueous humor is produced by ciliary process (posterior chamber) and reabsorbed by canal of Schlemm (anterior chamber)

decrease production:

  • acetazolamide
  • timolol (nonselective)

facilitate drainage:
- echothiophate (can prolong DOA of sux + ester LA)

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75
Q

What is strabismus correction? What unique considerations apply to the anesthetic management of these patients?

A

corrects the misalignment of the extraocular muscles and re-establishes the visual axis. Three key considerations:

  • increased risk of MH
  • increased risk of PONV
  • increased risk of activating the oculocardiac reflex (afferent CN V, efferent CN X)
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76
Q

which patient populations benefit from a TAP block?

A

TAP = transverse abdominal plane block
- unilateral peripheral nerve block that targets the nerves of the anterior and lateral abdominal wall

best for abdominal procedures (general, GYN, urologic) that involve T9 to L1
- bilateral TAP required for midline incision or laparoscopic surgery

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77
Q

describe the anatomy and landmarks required to perform a TAP block

A

superficial to deep:

  • subQ
  • external oblique m.
  • internal oblique m.
  • transverse abdominis m.
  • peritoneum

landmarks of the TAP form the triangle of Petit. These include:

  • external oblique
  • latissimus dorsi
  • iliac crest
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78
Q

define allodynia and give an example.

A

pain d/t a stimulus that doesn’t normally cause pain

ex: fibromyalgia

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79
Q

define dysesthesia and give an example.

A

abnormal and unpleasant sense of touch

ex: burning sensation from diabetic neuropathy

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80
Q

define neuralgia and give an example.

A

pain localized to a dermatome

ex: herpes zoster (shingles)

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81
Q

what is the defining characteristic between type I and type II complex regional pain syndrome?

A

CRPS is characterized by neuropathic pain w/ autonomic involveent.

Type I: reflex sympathetic dystrophy
Type II: causalgia

i.e. distinction is that type II is always preceded by nerve injury whereas type I is not.

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82
Q

discuss the use of a thoracic paravertebral block.

A

LA injected into the paravertebral space (potential space) targets the ventral ramus of the spinal nerve as it exits the vertebral foramen

  • creates unilateral sensory and sympathetic block for that dermatome
  • “single shot, unilateral epidural block”

best for breast surgery, thoracotomy, and rib fractures

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83
Q

what structures are anesthetized by a celiac plexus block? How about a superior hypogastric block?

A

celiac plexus

  • upper abdominal viscera (except L colon)
  • NOT the pelvic organs
  • useful for pain from upper abdominal organs but not pelvic organs

superior hypogastric plexus block

  • pelvic organs
  • useful in those involving pelvic organs

both useful in cancer patients

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84
Q

aside from an epidural blood patch, which regional technique is used to release post dural puncture headache?

A

sphenopalatine block

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85
Q

what is post-retrobulbar block apnea syndrome?

A

the optic nerve is unique b/c it is the only CN that is part of the CNS (enveloped by the meningeal sheath and bathed in CSF)
- thus LA injected into the optic sheath can enter the brain directly –> subarach block

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86
Q

discuss the use of cephalosporins in the PCN allergic patient.

A

previous literature suggested high cross-reactivity (up to 10%), but these numbers are grossly overstated.

if PCN allergy, pt may receive a cephalosporin if the reaction:

  • was NOT IgE mediated (anaphylaxis, bronchospasm, urticaria)
  • did NOT produce exfoliative dermatitis (Stevens Johnson syndrome)

otherwise, use vanco or clinda

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87
Q

what is the antibiotic of choice to treat MRSA? What are the special considerations for the administration of this antibiotic?

A

vanco

to reduce histamine release and hypotension, administer at a rate of 10-15mg/kg over 1hr

histamine response can be minimized by benadryl 1mg/kg + cimetidine 4mg/kg 1hr pre-anesthesia

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88
Q

discuss the different levels of infection control precautions. Give examples w/ specific pathogens.

A

contact precautions

  • transmitted by direct contact
  • gown, gloves
  • MRSA, VRE, C.diff

droplet precautions

  • transmitted by droplets
  • gown, gloves, mask
  • influenza, resp synctyial virus

airborne precautions

  • transmitted airborne
  • gown, gloves, N95, negative pressure room
  • TB
89
Q

what is the rate of seroconversion following exposure to HIV infected blood?

A

most common cause of occupational HIV exposure = needle stick injury w/ a hollow bore needle

rates:
- needle stick = 0.3%
- mucus membrane exposure = 0.09%

90
Q

what are the functions of the 5 types of WBC?

A

GRANULOCYTES:

  1. neutrophils (60%): fight bacterial, fungal infection
  2. basophils: hypersensitivity rxns (degranulate as mast cells)
  3. eosinophils: defend against parasites

AGRANULOCYTES

  1. monocytes: phagocytosis, release cytokines, present pathogens to T-lymphocytes
  2. lymphocytes: B-type (humoral immunity, Ab production), T-type (cell-mediated, no Ab production)
91
Q

describe the presentation of anaphylaxis

A

CV = hypotension, tachycardia, arrhythmias, cardiac arrest

resp = bronchospasm, laryngeal edema, mucus production

skin = flushing, urticaria, erythema, pruritus

GI = cramping, N/V, diarrhea

92
Q

what is the function of the H1 and H2 receptor?

A

H1

  • vasodilation
  • increased vascular permeability
  • smooth m. contraction (not vascular)

H2

  • cardiac stim (inc HR)
  • HCl secretion
93
Q

describe the patho of the 4 types of hypersensitivity reactions. List examples of each.

A

Type I: immediate hypersensitivity

  • Ag + Ab interaction
  • previous sensitization
  • ex: anaphylaxis, asthma

Type II: Ab-mediated

  • IgG, IgM Ab bind to cell surfaces
  • ex: ABO incompat, HIT

Type III: Immune complex mediated

  • immune complex is formed and deposited into tissues
  • ex: snake venom rxn, protamine-vasoconstriction

Type IV: delayed

  • allergic rxn delayed at least 12hrs after exposure
  • ex: contact dermatitis, graft-v-host disease, tissue rejection
94
Q

What is the treatment for intraoperative anaphylaxis?

A
  • d/c offending agent
  • a/w support: FiO2, ETT
  • epi (5-10mcg IVP for hypotension, up to 0.1-1mg for CV collapse)
  • liberal IVF (cryst 10-25mL/kg or colloid 10mL/kg)
  • H1, H2 blockers: benadryl 0.5-1mg/kg, ranitidine 50mg/pepcid 20mg IVP
  • hydrocortisone 250mg IV
  • albuterol for bronchospasm
  • vasopressin for refractory hypotension (0.01U/min start)
95
Q

what are the 3 most common causes of intraoperative anaphylaxis?

A 
1 = NMB (sux most common)
2 = latex
3 = antibiotics
96
Q

which patients are at the highest risk of a latex allergy?

A 
spina bifida/myelomeningocele
atopy
health care workers
food allergy to: 
- banana
- kiwi
- mango
- papaya
- pineapple
- tomato
97
Q

if you had to explain “chemo man” to a friend, could you do it? try it now for practice.

A

picture of the man

C: cisplatin (alkylating agent)
- acoustic n. injury, nephrotoxicity

V: vincristine, vinblastine (tubulin-binding drug)
- peripheral neuropathy

B: bleomycine (antitumor abx)
- pulmonary fibrosis (FiO2 <30%)

D: doxorubicin (antitumor abx)
- cardiotoxic

5, M: 5-fluorouracil, methotrexate (antimetabolite)
- bone marrow suppression

98
Q

what are the 5 most important GI hormones? What is the key function of each?

A

gastrin: increases stomach acid and stimulates chief cells to secrete pepsinogen (converted to pepsin) in response to food entering the stomach
secretin: stim pancreas to secrete HCO3- and liver to secrete bile

CCK: pancreas to release digestive enzymes and gallbladder to contract

gastric inhibitory peptide: slows gastric emptying, stim pancreatic enzyme release

somatostatin: universal off switch for digestion.

99
Q

what is gastric barrier pressure? Why is it important?

A

barrier pressure = LES pressure - intragastric pressure

the likelihood of GERD is determined by barrier pressure
- higher the barrier pressure = lower likelihood of reflux.

100
Q

what are the 3 most important inputs to the vomiting center? What receptors are involved in each one?

A

vomiting center is in the nucleus tractus solitarius (medulla)

sensory input via:

  1. chemoreceptor trigger zone (5-HT3, NK-1, DA-2, noxious chemicals)
  2. GI tract (5-HT3, NK-1)
  3. vestibular system (H1, M1)
101
Q

what is the mechanism of action of NK-1 antagonists? Give an example of a drug in this class.

A

neurokinin-1 antagonists block substance P in the chemoreceptor trigger zone

ex: aprepitant

102
Q

what are the risk factors for PONV? It helps to divide them into patient, surgical, and anesthetic risk factors.

A

patient:
- female
- nonsmoker
- hx of motion sickness
- previous PONV
- youth > elderly (loosely)

surgical:
- long procedures
- gyn, breast, plastics
- laparoscopy
- peds: strabismus, orchiopexy, T&A

anesthetic:
- halogenated anesthetics, N2O (>50%)
- opioids
- etomidate
- neostigmine

103
Q

name 2 antiemetics that prolong the QT interval.

A

droperidol

ondansetron

104
Q

list 2 contraindications for metoclopramide.

A

Parkinson’s (it’s a dopamine antagonist)

bowel obstruction (it’s a prokinetic agent)

105
Q

where is the P6 acupressure point, and why is it important?

A

nonpharmacologic method of reducing PONV

3 fingers across the inner wrist

106
Q

how long must the tourniquet remain inflated after a Bier block? Why?

A

300mmHg or 2x SBP for at least 20mins after LA injection

premature release can increase risk of seizure and/or cardiac arrest

107
Q

what physiologic changes accompany tourniquet deflation?

A

release stresses the body in 2 ways:

  • restoring blood flow to extremity produces relative decrease in circulating blood volume
  • products of cellular hypoxia enter systemic circulation
  • increased EtCO2
  • decreased core temp
  • decreased BP
  • decreased SvO2
  • metabolic acidosis
108
Q

discuss the role of the cyclooxygenase enzyme in the arachidonic acid cascade.

A

COX1 is always present, maintains normal physiologic function

  • inhibition impairs platelet function, causes gastric irritation, and decreases RBF
  • NSAIDs, aspirin

COX2 is not always present, just during inflammation

  • inhibition produces analgesia (ceiling occurs), anti-inflammation, antipyretic effects
  • COX 2 inhibitors AND NSAIDs, aspirin
109
Q

compare the equianalgesic dose of ketorolac and morphine.

A

toradol 30mg IV

morphien 10mg IV

110
Q

what is Samter’s triad? Why is it important?

A

aspirin exacerbated respiratory distress (Samter’s triad) refers to the combination of asthma, allergic rhinitis, and nasal polyps. These patients can develop life threatening bronchospasm after aspirin administration.

111
Q

list 4 herbal supplements that increase bleeding risk.

A

garlic
ginger
gingko
saw palmetto

112
Q

list 2 herbal supplements that reduce MAC

A

kava kava

valerian

113
Q

chronic ingestion of which herbal medication can mimic Conn’s syndrome?

A

licorice

114
Q

describe the modified Aldrete scoring system.

A

used to assess readiness for PACU discharge. score of 0-2 is awarded in 5 areas, where a score of 9 or more is generally accepted as discharge ready.

activity (moving)
respiration (breathing)
circulation (BP)
consciousness
O2 sats (on RA)
115
Q

compare and contrast android and gynecoid obesity.

A

android

  • more common in men
  • central/abdominal visceral fat accumulation
  • increased risk of ischemic heart disease, HTN, HLD, insulin resistance, death

gynecoid

  • more common in women
  • gluteal and femoral fat accumulation
  • metabolically inactive, primarily used for energy storage
  • increased risk of join disease, varicose veins
  • associated w/ reduced incidence of non-insulin dependent diabetes
116
Q

what are the diagnostic indicators for metabolic syndrome?

A

metabolic syndrome (syndrome X) = various disease states that coincide w/ obesity. CV risk is 50-60% greater than the gen pop.

must have at least 3 of:

  • waist circumf >40in men, >35in women
  • triglycerides > 150
  • HDL <40 men, <50 women
  • BP >130/85
  • fasting BS >100
117
Q

how can you use BMI to classify obesity?

A 
underweight BMI <18.5
normal 18.5-24.9
overweight 25-29.9
obese class I 30-34.9
obese class II 35-39.9
obese class III >40 (morbid)
118
Q

how can you classify obesity in children?

A

overweight: 85-94th weight percentile

obese: 95-98th
severely obese: 99th

119
Q

what is the formula for BMI?

A

weight (kg)/height (m^2)

120
Q

how can you calculate ideal body weight for a man? For a woman?

A

IBW describes the BMI associated w/ the lowest risk of body-weight related comorbidities.

men (kg) = cm -100
women (kg) = cm - 105

121
Q

describe how obesity creates a restrictive ventilatory defect.

A

lung inflation is inhibited d/t:

  • chest fat compressing rib cage and hindering outward expansion
  • abdominal fat shifting diaphragm cephalad, compressing lungs
  • kyphosis/lordosis develop over time and alter ribcage geometry

extra weight on the chest increases WOB. Rapid, shallow breathing pattern provides the most energy efficient way to achieve this goal

122
Q

how does obesity affect respiratory gas tensions?

A

fat is metabolically active, thus pts have increased oxygen consumption and CO2 production –> MV must be increased

while pt may have hypoxemia, PaCO2 is usually normal. This is d/t high diffusing capacity of CO2. High PaCO2 signals impending respiratory failure.

123
Q

how does obesity affect FRC? How about the other lung volumes and capacities?

A

FRC is inversely proportional to BMI.

  • FRC < CC = small airway collapse during tidal breathing
  • -> V/Q mismatch, shunt, hypoxemia

GA causes FRC to decrease by 50% (nonobese = 20%)
- + higher O2 consumption = decreased safe apnea time.

decreased VC, TLC, ERV, FRC
normal RV

124
Q

how you can you reduce atelectasis in the morbidly obese patient who is mechanically ventilated?

A

keep FiO2 <80% to prevent absorption atelectasis.

to recruit alveoli:

  • reopen collapsed alveoli w/ recruitment maneuvers (40cmH2O x10sec)
  • hold open the re-expanded alveoli w/ PEEP or CPAP

both maneuvers may cause decreased venous return and cause hypotension

125
Q

what is the optimal tidal volume for a morbidly obese patient who is mechanically ventilated?

A

6-8mL/kg of IBW

higher Tv may only minimally increase PaO2 and may cause sheer stress to the lungs

126
Q

does a morbidly obese patient require RSI? Why or why not?

A

obesity alone doesn’t mandate a RSI
- consider other risk factors though.

conflicting evidence re: effects of obesity on gastric pH, residual volume, and emptying time. No data supports an increased aspiration risk in obesity.

127
Q

how does obesity impact the cardiovascular system?

A
  1. increased intravascular blood volume
  2. high CO
    - adipocytes require vascular growth to support their growth, requiring increased blood volume and CO
    - increased CO is d/t increased SV (normal HR)
    - increased CV workload –> thick, dilated heart –> decreased ventricular compliance –> diastolic, systolic dysfunction

HTN is d/t hyperinsulinemia, SNS and RAAS acitvation, and elevated plasma [cytokine]

128
Q

describe the EKG changes that can accompany obesity.

A 
low voltage
L axis deviation (mass effect)
R axis deviation (hypertrophy)
QT prolongation
ischemia
dysrhythmias (fatty infiltrates, etc. )
129
Q

what valvular defect is highly suggestive of pulmonary HTN in the obese patient?

A

tricuspid regurg

130
Q

what factors affect the volume of distribution in the obese patient?

A

increased blood volume
increased CO
altered protein binding
larger mass for lipid solubilty

–> increased Vd for both lipophilic and hydrophilic drugs (lipophilic more tho)

131
Q

how does obesity impact your selection of inhaled anesthetic agents?

A

MAC doesn’t change

IA are lipophilic, so use agents w/ lowest blood:gas coefficients

sevo or des = faster emergence than iso, propofol

N2O is generally avoided b/c it restricts the max FiO2 that can be delivered.

132
Q

how does obesity affect the dosing of propofol?

A

loading dose is based on LBW b/c redistribution limits it’s effects, not clearance

maintenance dosing based on TBW

133
Q

how does obesity affect the dosing of succinylcholine?

A

TBW

this is a clear exception to the rule for water soluble drugs. although there is increased Vd, there is also increased pseudocholinesterase activity that offsets the Vd

134
Q

how does obesity affect the dosing of nondepolarizing neuromuscular blockers?

A

roc and vec = LBW

cis and atra = TBW

135
Q

how does obesity affect the dosing of opioids?

A

fent, sufenta (fat soluble, large Vd) expect prolonged E1/2t:

  • loading TBW
  • maintenance: LBW

remi always LBW (behaves like a low Vd drug d/t it’s clearance)

136
Q

how does obesity affect the dosing of an epidural?

A

engorgement of the epidural veins and an increased epidural fat content will cause a greater spread of LA in the epidural space

dose should be reduced to 75% of the normal dose

137
Q

name the key muscles that control the diameter of the upper airway and describe their functions.

A

pharynx = collapsible tube
airway patency is maintained by the balance b/n pharyngeal muscles that dilate the airway and negative pressure of inspiration that collapses it.

tensor palantine
- opens nasopharynx
genioglossus
- opens oropharynx
hyoid muscles
- opens the hypopharynx
138
Q

define hypopnea.

A

a 50% reduction in airflow for 10 seconds, 15x or more per hour, and is linked to snoring and decreased O2 saturation

139
Q

discuss the pathophysiology of OSA.

A

cessation of airflow for at least 10 seconds (apnea) with 5 or more unsuccessful efforts to breathe (obstruction) and >4% reduction in SaO2

leads to hypoxemia, hypercarbia, and arousal from sleep

  • -> ANS stimulation, daytime somnelence
  • -> systemic HTN, dysrhythmias, MI, pHTN, HF
140
Q

what is the definitive test for OSA? What does it measure? how do you interpret the findings?

A

polysomnography

AHI (apnea-hypopnea index) = # apnea/hypopnea episodes/hr

mild = 5-15
mod = 15-30
severe >30

141
Q

what is the best bedside tool to identify undiagnosed OSA? How do you interpret the findings?

A

STOP BANG
high risk 3+ yes
low risk <3 yes

Snoring
Tiredness
Observed apnea
Pressure
BMI
Age
Neck circumference
Male gender
142
Q

what is obesity hypoventilation syndrome? How do you identify a patient w/ this condition?

A

(aka Pickwickian syndrome)
long term consequence of untreated OSA = failure of resp center in medulla to respond to increased PaCO2 appropriately –> apnea during sleep w/out resp effort

diagnostic:
- BMI >30
- awake PaCO2 >45
- dysfunctional breathing asleep

signs

  • obesity
  • daytime hypersomnelence
  • hypoxemia, hypercarbia
  • resp acidosis w/ comp
  • polycythemia
  • pHTN
143
Q

what are the most common signs of an anastomotic leak following gastric bypass?

A

(2% incidence)

unexplained tachycardia is the most sensitive sign (>120)

others: fever, abdominal pain

toradol increases the incidence of this complication, so avoid.

144
Q

what is Ma huang? what are the complications of its use?

A

natural source of ephedrine

any drug interactions that would occur w/ ephedrine will apply here as well

complications of adrenergic overstim, HTN, CVA, sz, death have occurred

145
Q

what is Orlistat? what are the complications of its use?

A

lipase inhibitor
reversibly binds lipase and hinders the absorption and digestion of consumed fats

decreased fat, vitD, vitA, vitK, vitE absorption (requires supplementation)
- decrease in vitK dependent clotting factors

146
Q

How does the Trendelenburg position affect the distribution of blood volume, MAP, and venous pressure?

A

increased venous return = increased position on Frank-Starling (caution w/ HF)

MAP + or no change
- since vasodilation and HR decrease follows increased venous return

venous pressure increases

can lead to edema of the face, eye, and airway, and intracranial HTN

147
Q

how do position changes affect respiratory function?

A

trendelenburg

  • compressed lungs, decreased pulmonary compliance
  • increased PIP
  • decreased TLC, FRC

reverse T

  • expanded lungs, increased pulmonary compliance
  • decreased PIP
  • increased TLC, FRC
148
Q

how do position changes affect the position of the ETT?

A

neck position:
- flexion = ETT toward the carina
- extension = ETT toward VC
“tube goes where nose goes”

carina position
- T burg = carina toward ETT

149
Q

which positions increase the risk of post op airway edema, and how can you assess the severity of this complication?

A

edema of the face, tongue, pharynx can affect airway patency

  • prone, Tburg = increased hydrostatic pressure
  • sitting = neck flexion impairs venous drainage

if you are concerned about airway patency pre-exutbation, then you can perform a leak test and/or visually inspect w/ DL

150
Q

discuss how the brachial plexus is susceptible to stretch and compression injury.

A

stretch injury since it’s anatomically fixed at the cervical vertebrae and the axillary fascia
- risk is highest w/ abducted arms >90degrees and/or head rotated to the side

compression injury b/n clavicle and first rib or by an external force (shoulder brace, bean bag)

151
Q

should shoulder braces be used for the patient in Tburg position? Why or why not?

A

No - a non-sliding mattress is a better option

if used, they should be placed over the acromion
- avoid placement near base of neck or midway along the clavicle to decrease risk of compression injury

152
Q

how do you assess a patient for thoracic outlet syndrome? Which surgical position increases the likelihood of this complication?

A

clasp hands behind head - if pt complains of pain, this may suggest an increased risk of TOS

most likely to occur in any position where the arms are over the head (i.e. prone)

153
Q

where should an axillary roll be placed for the patient in the lateral decubitus position?

A

distal to the axilla

a roll placed inside the axilla can cause neurovascular compression
- a poor SpO2 signal in the dependent arm is a good monitor for this.

154
Q

describe the anatomy of the cubital tunnel.

A

boundaries:
- medial epicondyl of humerus
- olecranon process of ulna
- cubital tunnel retinaculum

ulnar nerve emerges from the cubital tunnel b/n the humeral and ulnar heads of the flexor carpi ulnaris.

155
Q

who is at risk for ulnar nerve injury?

A

*most commonly injured peripheral nerve

male gender (esp >50yrs)
preexisting ulnar neuropathy
extremes of body habitus
prolonged LOS/bedrest

156
Q

describe the presentation of ulnar nerve injury.

A

impaired sensation of the 4th and 5th digits

inability to abduct (oppose) the pinky finger

chronic injury presents w/ claw hand (muscular atrophy)

157
Q

which type of nerve injury provides a greater risk for long term injury (sensory or motor)?

A

sensory are more common, less serious, and tend to resolve on their own (usually <5 days)

motor deficits are less common and more serious

158
Q

what are the causes of median nerve injury?

A

AC PIV
carpal tunnel syndrome
elbow hyperextension
- including forced extension during position after NMB

159
Q

describe the presentation of median nerve injury.

A

reduced sensation over palmar surface of thumb, index finger, middle finger, and lateral aspect of the ring finger

inability to oppose the thumb (chronic injury can lead to the ape hand deformity)

160
Q

what are the causes of radial nerve injury?

A

radial nerve passes along the spiral groove at the lateral aspect of the humerus (3 FB above the lateral epicondyle)

etiology:
- external compression (i.e. IV pole)
- excessive NIBP cycling
- UE tourniquet
- too tight of tucking w/ sheets

161
Q

describe the presentation of radial nerve injury.

A

wrist drop (inability to extend the hand at the wrist)

162
Q

discuss the etiology, presentation, and prevention of obturator nerve injury.

A

etiology: excessive flexion of thigh toward groin, excessive traction during lower abdominal surgery, or forceps delivery
presentation: inability to adduct the leg, reduced sensation over medial thigh
prevention: minimize hip flexion

163
Q

discuss the etiology, presentation, and prevention of femoral nerve injury.

A

etiology: excessive traction during lower abdominal surgery
presentation: impaired knee extension, hip flexion, reduced anterior thigh/anteromedial leg sensation
prevention: avoid excessive traction

164
Q

discuss the etiology, presentation, and prevention of saphenous nerve injury.

A

etiology: medial aspect of leg leans against supporting cradle in lithotomy position
presentation: reduced sensation over anteromedial aspect of leg
prevention: padding b/n leg and stirrup

165
Q

discuss the etiology, presentation, and prevention of common peroneal nerve injury.

A

etiology: stirrups (highly susceptible here when lateral aspect of the leg leans against the stirrup bar)
presentation: foot drop, inability to evert foot or extend toes
prevention: padding, knees flexed w/ minimal rotation

166
Q

discuss the etiology, presentation, and prevention of sciatic nerve injury.

A

etiology: lithotomy w/ extreme hip flexion and/or external rotation; sitting w/ straight legs
prevention: ample padding under buttocks, avoid excessive external hip rotation, flex table at the knees
presentation: foot drop

167
Q

which position is most likely to cause compartment syndrome?

A

lithotomy

  • increased leg compartment pressure
  • raising legs above heart reduces LE perfusion pressure
  • together –> leg ischemia –> edema –> more ischemia –> more edema, etc.
  • this can progress to rhabdomyolysis and/or reperfusion injury

compartment syndrome is treated w/ fasciotomy

168
Q

which position is most likely to cause a venous air embolism?

A

sitting
but this complication can occur in any position that produces a pressure gradient b/n the atmosphere and the veins at the surgical site

VAE –> R heart –> pulm vasculature –> increased dead space, RV workload

169
Q

which position is most likely to cause midcervical tetraplegia?

A

associated w/ hyperflexion of the neck (chin to chest). Ischemia results d/t stretching and/or compression of the midcervical SC (usually C%)

most common in sitting position

should be able to place 2 FB b/n chin and chest

170
Q

what is the purpose of a positioning device for a patient in the prone position?

A

(chest rolls, wilson frame, jackson table (best))

distribute the patient’s weight to the thoracic cage and bony pelvis, allowing the abdomen to hang freely , which promotes normal diaphragmatic excursion throughout the respiratory cycle

171
Q

which position provides the most optimal VQ matching in the patient w/ ARDS?

A

prone

172
Q

list 3 factors that worsen tracheobronchial compression in the patient w/ an anterior mediastinal mass.

A

supine position
GA induction
PPV

173
Q

what is the best induction technique for a patient w/ an anterior mediastinal mass?

A

sitting and maintenance of SV

174
Q

what are your options if you lose the airway during induction in the patient w/ an anterior mediastinal mass?

A

may be impossible to advance the ETT beyond the mass.

try repositioning lateral or prone, using rigid bronchoscope

if unable to ventilate, emergent fem-fem CPB may be required

175
Q

what is the AANA code of ethics?

A

dictates the principles of conduct and professional integrity that guide the decision making and behavior of CRNAs

speaks to responsibilities as a professional, which hods the CRNA accountable for their own actions/judgements regardless of institutional policy or physician orders.

176
Q

what are practice guidelines?

A

systematically developed statements to assist providers in clinical decision making that are commonly accepted w/in the anesthesia community.

“should” be adhered to

177
Q

what are practice standards?

A

authoritative statements that describe minimum rules and responsibilities for which anesthetiists are held accountable

“must” be adhered to.

178
Q

what are position statements?

A

express the AANA official positions or beliefs on practice related topics; they may also define the knowledge, skills, and abilities considered necessary for a nurse anesthetist.

179
Q

define autonomy.

A

pt’s ability to choose w/out controlling interference by others, and w/out limitations that prevent meaninful choices.

180
Q

define nonmaleficence

A

asserts that a provider has an obligation not to inflict hurt and harm - in other words, the Hippocratic oath primum non nocere (first do no harm)

181
Q

define beneficence.

A

the principle that providers should take action for the benefit of others, including both preventing harm adn actively helping their patients.

underpins to the fundamental guiding principle of evidence based interventions - the benefits of treatment should be demonstrable and must clearly outweigh the risks.

182
Q

list the 6 elements of informed consent.

A 
competence
decision making capacity
disclosure of information
understanding of information
voluntary consent
documentation
183
Q

what is informed refusal? list one example of this concept in a specific patient population.

A

pt has a right to refuse medical treatment or therapy

common example is refusal of blood products by Jehovah’s Witness.

184
Q

what is an advanced directive?

A

legally binding document that delineates the pt’s wishes regarding healthcare interventions in the case of incapacity and/or delegates the authority to another party

often include specific provisions that modify aspects of anesthesia management (intubation, abx, transfusions, etc.)

185
Q

list the 4 things that must be proven in a lawsuit asserting malpractice.

A

duty
breach of duty
causation
damages

186
Q

what is res ipsa loquitur?

A

“the thing speaks for itself” can shift the burden of proof from the plaintiff to the defendant. This can occur if 4 conditions can be established:

  • injury wouldn’t have occurred w/out negligence
  • injury was caused by something under complete control of the provider
  • pt didn’t contribute in any way to the injury
  • evidence for the explanation of events is solely under control of the provider.
187
Q

what is the difference b/n libel and slander?

A

libel is defamation in the written form

slander is defamation in the verbal form

188
Q

what is the difference b/n assault and battery?

A

assault is the attempt to touch another person

battery is touching another person w/out either expressed or implied consent

189
Q

what is vicarious libaility? What is another name for this concept?

A

one person (or entity) may be liable for the actions of another. For example, a physician may be held liable for actions of a PA. The concept doesn’t typically apply to CRNAs working under a physician.

other name: Respondeat superior

190
Q

what is the patient care and affordable care act?

A

ACA mandated that all individuals carry health insurance, established standards and requirements for health insurance policies, and launched health care clearinghouses or exchanges to assist people in finding medical insurance.

in addition, insurers are no longer permitted to charge more for pre-existing conditions

191
Q

what is emergency in medical treatment and active labor act?

A

> 30yrs ago, this was enacted (EMTALA) to ensure public access to emergency services regardless of ability to pay. “anti-patient dumping” act.

specific obligations on medicare-participating hospitals that offer emergency services: provide a medical screening examination when request is made for an emergency medical condition regardless of ability to pay.

192
Q

what is the health insurance portability and accountability act?

A

federal law that prohibits the disclosure of individually identifiable health information. PHI includes past and present health conditions, treatments, and payments for healthcare.

disclosure can occur in any form: orally, written, or electronically

193
Q

what is the controlled substances act?

A

federal gvt regulation of the manufacture, importation, possession, and distribution of drugs deemed “controlled substances” by the gvt.

194
Q

what schedule I drugs are used to provide anesthesia?

A

schedule I drugs have no currently acceptable medical use, therefore we don’t use any.

as an aside, the legalization of marijuana at the state level challenges it’s schedule I designation at the federal level

195
Q

what is a schedule II drug? list some examples.

A

high potential for abuse potentially leading to dependence

opioid agonists
cocaine
methamphetamine
phencyclidine

196
Q

what is the health information technology for economic and clinical health act (HITECH)?

A

intended to create a healthcare information technology infrastructure in order to improve care quality and coordination b/n providers

amendment to HIPAA, and applies to the same covered entities including providers, health plans, and healthcare clearinghouses. widened the scope of privacy and security protections available under HIPAA

197
Q

detail the steps involved w/ responding to a lawsuit.

A
  • notify insurance carrier
  • do not alter records or discuss the case
  • gather all records of the case
  • make notes re: all aspects
  • cooperate w/ insurers attorney

work w/ attorney to write an initial response to the summons

discovery: gathering of facts
written interrogatory: request for factual info and document exchange
deposition: questioning

198
Q

what is an emancipated minor?

A

pts <18yrs old who are legally given the rights of an adult by a state court. although variable by state law, criteria for emancipating a minor may include the fact that they are:

  • marrier
  • a parent, or currently pregnant
  • in the military
  • economically independent
199
Q

discuss the ethical dilemma of surgery for a child of Jehovah’s Witness.

A

families should be informed that, despite all reasonable efforts to eliminate need for transfusion, if emergency occurs, a court order for transfusion will be sought.

when likelihood is high, court order should be sought pre-op. in life-threatening crisis, emergency transfusion should be given prior to obtaining a court order

as these children approach maturity, they should be involved in the decision making

200
Q

what is anesthesia crisis resource management?

A

in an anesthetic crisis, effective response and management is dependent upon non-technical skills. crisis resource management uses a simple model in which effective communication is the glue that holds all teh other components together.

resources available include all the personnel involved and their inherent knowledge, skills, and abilities. resources also include supplies, pharmaceuticals, technology, and information

201
Q

list 5 complications of fatigue.

A
  • decreased reaction time
  • impaired decision making
  • decreased situational awareness
  • impaired concentration/memory
  • periods of microsleep
202
Q

what is microsleep?

A

an actual sleep episode that lasts seconds to minutes; it is insidious in a fatigued provider and cannot be predicted. performance b/n microsleep episodes is impaired, and errors of omission increase

203
Q

what is the relationship b/n 24hrs of wakefulness and alcohol consumption?

A

24hrs wakefulness = 0.1% BAC

204
Q

when is sleep-related behavior most common?

A

after 16+ hrs of continuous work

night shift

205
Q

list 6 countermeasures for fatigue

A 
napping
caffeine
exercise
consistent sleep/wake 
medications
recovery b/n shifts
206
Q

what is the OSHA limit for occupational exposure to ionizing radiation?

A

annual = 5 rem

lifetime = (N-18) x5rem
- N= age in years

207
Q

what are the physiologic effects of MRI exposure?

A

lower frequency electromagnetic fields from MRI can cause transient symptoms of nausea, dizziness, vertigo, or light flashes

208
Q

what are the OSHA limits for noise exposure?

A

for an 8hr span = 90dB

single noise level <115dB

209
Q

who is the “second victim”?

A

the provider
- the provider’s subsequent patients are possible “third victims”

being involved w/ a case w/ a bad outcome is one of the most significant acute stressors for an anesthesia provider

210
Q

define addiction.

A

need (psychological or compulsive) for a substance.

there is often a loss of self-control, where the user continues using a drug despite the desire to stop drug use. This represents a severe stage of chronic substance abuse disorder.

211
Q

define impairment

A

inability to safely participate in life (or professional) activities

212
Q

define tolerance.

A

more drug is needed to achieve a given effect (intoxication) - or - a lesser effect is produced by a given dose of drug.

213
Q

define withdrawal

A

characteristic syndrome that is the direct result of stopping or reducing the use of a drug

214
Q

list the risk factors for developing substance use disorder.

A

psychological:
- anxiety/depression
- low self esteem
- low tolerance for stress

behavioral/social

  • risk seeking behavior
  • poor coping skills
  • personal/family hx addiction
  • hx trauma, abuse, stress

physical
- acute/chronic pain

workplace specific:

  • production pressure
  • fatigue/burnout
  • irregular work hours
  • poor work/life balance

anesthesia specific:

  • access/availability
  • access to unregulated drugs
  • sensitization to the effects of drugs
215
Q

what are some typical behaviors of the impaired provider?

A
  • frequent/unexplained tardiness, absence, etc.
  • poor performance
  • confusion, memory loss
  • mood swings, personality changes
  • visibly intoxicated
  • refusal of drug testing
  • track marks, bloodshot eyes, significant weight loss or gain
216
Q

what are the key issues regarding re-entry to clinical practice following a substance abuse disorder?

A

safe return is determined on an individual basis

readiness is a collaborative decision of the monitoring program, counselor, and employer. 1 full year of recovery is recommended

d/t high risk of relapse, abstinence based recovery and refraining from substitute treatments is also recommended.

of the ten criteria that should be met prior to considering re-entry, the most salient point is participation in a monitoring program at least 5yrs in length w/ random drug testing.

217
Q

what should you do if you suspect a fellow anesthesia provider is impaired?

A
  • don’t let them out of your sight
  • don’t let them drive
  • have a bed in a tx facility available
  • don’t let the impaired person decide their treatment
  • only when all else fails, threaten to call the police
218
Q

what are the 6 elements of high-quality care?

A 
patient centered
safe
effective
timely
efficient
equitable
219
Q

discuss cultural competence in the context of anesthesia delivery

A

strategy to reduce health care disparities and improve equity.

requires the anesthesia provider to:

  • know and apply current standards of care
  • offer and use evidence based interventions
  • have a keen awareness of their own biases and assumptions
  • be sensitive to the presence of health disparities and discrimination

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