Quiz 1 Flashcards
What temp should the OR be kept at according to the Joint Commission?
75 F or 24 C
What are some interventions for preventing hypothermia?
Bair hugger, room temp, fluid warmers, low flows on machine, minimize skin exposure
What role does humidity play in the OR and what is recommended relative humidity?
decreases likelihood of static discharges; 50%
What is Ohm’s law in terms of electricity?
E=IxR (I is current in amperes, R is resistance)
To achieve electrical shock, one must contact the circuit at…
2 points
What is the maximum electricity leakage of OR equipment?
10 microamps
What are the 4 primary processes for heat loss?
radiation, convection, conduction, evaporation
Which mechanism is the most significant of heat loss by our bodies?
radiation
What is convection in terms of heat loss?
bodies transfer kinetic energy to air molecules on surface of skin- heated molecules rise and are replaced with colder air molecules
What is conduction (heat loss)? What population is especially susceptible?
transfer of heat by physically touching a less warm object; pediatrics (large BSA to mass)
What is evaporation?
phase change from liquid to gas requiring energy (sweat, surgical prep agents)
Vapor pressures and boiling points are ? related
inversely
What are volatile liquids?
liquids that have high vapor pressures at room temperature
What is the VP of iso, sevo, and des, respectively?
238, 160, 660
What is the difference between evaporation and vaporization?
evaporation does not require heat for liquid to turn into gas
What are the 3 requirements for fire?
flammable agent, source of ignition, gas that supports combustion
Which gases support combustion?
oxygen and nitrous oxide
What should you do in the event of airway fire?
stop ventilation, disconnect circuit, remove ETT, pour water/saline down pharynx, BMV until new airway established
What are some ways to prevent OR fire?
titrate FiO2 to minimum amount necessary, avoid use of N2O, vent excess O2 from under drapes/tenting
If a patient had a stent placed, how long are they not eligible for outpatient surgery?
6 weeks (bare metal), 1 year (drug eluding)
What is S.A.F.E. anesthesia?
Short acting fast emergence
What are some agents/techniques used for preemptive analgesia?
Cox 2 inhibitors, tylenol, ketamine, local anesthetic field block
What are some potential complications of SAB (subarachnoid block) that are particularly undesirable for outpatient settings?
PDPHA (postdural puncture HA), hypotension, urinary retention, delayed ambulation
What are some discharge requirements for outpatient procedures?
stable VS for 1 hour, no respiratory distress, off O2 for at least 30 min, A&Ox3, minimal PONV, no active bleeding/oozing, pain under control, responsible adult escort, ability to void/walk
What are some risk factors for PONV?
younger age, female, nonsmoker, type of procedure (abdominal, cataract), history of PONV, anxiety, noncompliance with NPO guidelines, pain, obese, pregnant
What are some ways to prevent PONV?
TIVA, avoid nitrous, scopolamine patch, Zofran 8 mg, Decadron 5-10 mg, Emend 40 mg
What kind of contrast is media is preferred?
nonionized
What are some ways to prevent/treat CIN (contrast induced nephropathy)?
d/c metformin, adequate hydration, maintain good u.o., bicarb infusion
How do you treat contrast media reactions?
O2, bronchodilators, epi (10-20 mcg), corticosteroids (8-12 mg decadron), antihistamines
What is the pretreatment for known contrast media reactions?
hydrocortisone and benadryl
What type of metals cannot be taken near MRI?
ferrous metals (iron, nickel, cobalt)
What kind of changes in VS will you see with ECT therapy?
abrupt parasympathetic discharge (bradycardia) followed by sympathetic discharge (tachycardia)
Describe the anesthesia process for ECT
induction agent (methohexital, propofol), succs, ventilate, place bite block, induce seizure, ventilate
What are some renal changes that occur with aging?
atrophy, decreased RBF, decreased GFR and renal drug clearance
What renal complications are the elderly at risk for?
fluid overload, accumulation of drugs that are excreted by kidneys, prolonged drug effect, F&E imbalance
What are some hepatic changes that occur with aging?
decreased clearance, prolonged half life, decreased Vd of hydrophilic drugs (increased plasma concentration), increased Vd of lipophilic drugs, decreased mass, decreased BF, decreased albumin and enzyme activity
What are some endocrine changes that occur with aging?
defective glucose/insulin control (increased risk for adverse reactions with CV disease)
At what age do physiologic functions peak and how much do they decline per year?
30, 1%
Why do elderly patients have impaired thermoregulation?
loss of lean body mass (malnutrition), increased total body fat, decreased senses (less eating), decreased BMR, decreased TBW, reduction in blood volume, impaired shivering, decreased hypothalamus function
What are some complications of hypothermia?
slows anesthetic elimination, prolongs recovery from anesthesia, impairs coag, increases shivering risk (increased O2 consumption)
What are some cardiovascular changes that occur with aging?
less compliant heart and vascular system, increased SBP, ventricular thickening, higher circulating catecholamines but decreased responsiveness, prolonged circulation time, calcification of SA node (AF, SSS, heart blocks), wider pulse pressure
How is functional capacity/exercise tolerance measured?
metabolic equivalents (METs)
How do elderly patients increase CO, and what are they more dependent on?
increasing EDV instead of heart rate; atrial kick
What are some respiratory changes that occur with aging?
decreased chest wall compliance (calcification), flattening of diaphragm, loss of elastic recol, reduced functional alveolar surface
What changes occur to dynamic and static lung volumes with age?
decreased: VC, IRV, ERV, TLC, FVC, FEV1
increased: RV, FRC, CC
What are some mechanisms behind impaired oxygenation in the elderly?
decline in PaO2 due to premature closing of small airways, decreased ventilatory response to hypoxemia and hypercarbia
What are some CNS changes that occur with aging?
progressive loss of neurons, decreased NT activity and brain mass (esp. frontal lobe), decreased CSF, decreased CMRO2
Why are older patients more sensitive to general anesthetics, opioids, and benzos?
decreased available receptors
Which body system is most likely to have complications in the elderly?
neurologic
What patients are at risk for POD?
age >70, history of delirium or depression, ETOH abuse, pre-op narcotic use, ortho procedures
What are some drug considerations for the elderly in anesthesia?
age related decrease in MAC, reduced anesthetic requirements, avoid premedication, avoid benzos, sedatives, and anticholinergics that cross BBB (scopalamine)
How much does MAC decrease per decade after 40?
6%
What induction agent is preferred in the elderly due to its CV stability?
etomidate
What are expected changes in diastolic and systolic functioning with aging?
decreased diastolic functioning, systolic functioning should remain the same
