PHCY 402 Exam 1 Example
Questions And Accurate
Answers
is a bear in a cage an example of a hazard or a risk? - Answer hazard
using the sun as an example, determine toxicity, hazard, exposure, and risk - Answer
-toxicity: UV radiation causes DNA strand breaks and induces DNA damage
-hazard: UV is harmful, it can cause sunburns and skin cancer (individuals have
different susceptibilities to sunburns
-exposure: being outside in the sun
-risk: skin cancer frequency (elevated if not reducing UV radiation)
Give an example of hazard vs risk using a shark - Answer -hazard: shark in the ocean
-risk: once an individual enters the ocean (has exposure)
Which compound is the most effective - Answer E, because it reaches the highest on the
y-axis
which compound is the most potent - Answer the red compound
-it has the smallest ED 50
Why is the therapeutic index used - Answer used for drug safety
-determines how safe a drug is
-the larger the TI=more safe the drug is
If the LD50=10 and the ED50=2, find the therapeutic index - Answer 10/2= 5
if the LD1 =5 and the ED99 =9, find the margin of safety - Answer 5/9=0.56
what are the 4 steps of risk assessment - Answer 1) hazard identification: what causes
hazard
2) exposure assessment: routes, quantity, and duration
3) toxicity assessment: dose-response curves, therapeutic index, potency, efficacy
4) risk characterization: compilation of data, mitigation strategies, take action, reduce
,exposures
toxicity - Answer ability to cause an adverse effect
hazard - Answer potential to cause an adverse effect in a given situation or setting
(likelihood)
exposure - Answer coming into contact with a substance
risk - Answer expected frequency of the occurrence of an adverse effect arising from
exposure
T/F: the amount of time (duration) of an exposure can impact the toxicity - Answer true
toxicokinetics - Answer ADME of toxins, toxic doses of therapeutic agents, and
associated metabolites
-what the body does to the toxins
toxicodynamics - Answer injurious effects of toxins, toxic doses of therapeutic agents,
and associated metabolites on the functioning of the body
-what the toxin does to the body
initial management of a poisoned patient - Answer -ABCD's
-history and physical examination
-decontamination
-antidotes
-enhancement of elimination
ABCD's of poisoning - Answer -A: airway, clear of obstruction, move flaccid tongue out
of the airway, lay lateral, left-side down
-B: breathing, observation, pulse oximetry, or measured arterial blood gases, intubate
and mechanically ventilate if needed
-C: circulation, continuously monitor pulse rate, blood pressure, urinary output, and
peripheral perfusion
-D: dextrose, challenge with concentrated dextrose if patient has altered mental
status/appear intoxicated (unless bg test confirmed not hypoglycemic)
decontamination procedures for toxins - Answer remove any unabsorbed poison from
the skin or GI tract
-skin: remove clothes and wash the patient
-GI Tract: activated charcoal, gastric lavage, bowel irrigation
, List in order the elimination enhancing procedures for toxins - Answer *used AFTER
diagnostics and decontamination procedures
1) antidotes if available (react with toxin or increase metabolism)
2) hemodialysis
3) forced diuresis and urinary pH manipulation (to accelerate renal excretion)
anion gap formula - Answer (Na + K) - (HCO3 + Cl)
normal anion gap - Answer 12-16
-if larger: renal failure, shock-induced lactic acidosis
If a patient had an anion gap of 13 mEq,L, would this indicate renal failure? - Answer no
osmolar gap formula - Answer measured osmolality - calculated osmolality
what is included in calculated osmolaity - Answer Na, glucose, BUN
What tests are included in determining the osmol gap - Answer -Na
-BUN
-Glucose
-Osmolality
Normal osmol gap - Answer zero
-if larger (over 3): indicated alcohol
large vs small Vd - Answer large: Vd > 5 L/Kg
small: Vd < 1 L/Kg
hemodialysis is a method of "cleaning blood" to increase the elimination of a toxin,
would hemodialysis be effective in reducing the concentration of Prozac in a patient -
Answer no, antidepressants are distributed to other tissues (throughout the body) so
cleaning the blood wouldn't be effective
-hemodialysis would only be effective at cleaning something with a small Vd
large Vd examples - Answer antidepressants, antipsychotics, antimalarials, opioids,
verapamil
small Vd examples - Answer salicylate, acetaminophen, ethanol, lithium, and phenytoin
total clearance= - Answer excretion by kidneys + metabolism by the liver