Toxicological Emergencies - Norkus (1)

Question 1

4 primary routes of exposure

Answer 1

1) ingestion
2) inhalation
3) injection
4) topical

Question 2

initial assessment and stabilization of toxin patients

Answer 2

ABCs +/- CPCR, intubation, ventilation, IVC, IVF, O2, seizure control, emergency drug therapy
laboratory samples
monitoring
second evaluation - PE, history

Question 3

most common way a toxicity is diagnosed

Answer 3

history, patient signs, treatment response

Question 4

primary goal of deontamination

Answer 4

prevent initial absorption or further absorption

Question 5

topical decontamination

Answer 5

bath with mild hand or dishwashing detergent

Question 6

ocular decontamination

Answer 6

flush eyes with copious amounts of warm water or NS for >15m

Question 7

ingested decontamination - corrosive, strong acids or strong bases

Answer 7

rapid dilution w/ milk or water
avoid emesis - esophageal damage

Question 8

when is emesis contraindication

Answer 8

corrosive, strong acid/base, rabbits, rodents, comatose, seizing, severely depressed, dyspneic, hypoxic
strychnine or other CNS stimulants - may precipitate seizures

Question 9

how much of stomach contents is removed w/ emesis

Answer 9

40 - 60%
must remember rate of absorption!
emetics are more effective shortly after ingestion and when food is present in stomach

Question 10

two mechanisms of emetics

Answer 10

stimulation of chemoreceptor trigger zone (CRTZ)

direct gastric irritation

Question 11

apomorphine

Answer 11

D1 and D2 dopaminergic agonist (CRTZ stimulant)
side effects: CNS depression or excitement (cats)
0.04 mg/kg IV or 0.08 mg/kg IM, SC, or conjunctival sac

metoclopramide (dopaminergic antagonist) can reverse vomiting
naloxone can reverse CNS depression
may be negated by acepromazine or other dopaminergic antagonists

Question 12

Alpha-2 adrenergic agonist

Answer 12

feline emetic
dexmedetomidine (7-10 mcg/kg IM)
xylazine (0.44 mg/kg IM, SC)

side effects: bradycardia, arrhythmias, respiratory depression, sedation

reversal; atipamezole, yohimbine

Question 13

Hydrogen peroxide

Answer 13

H2O2 - direct gastric irritation
1 - 2 mL/kg PO
refractory vomiting, esophagitis
only for life-threatening toxin ingestion when others are not available

Question 14

gastric lavage

Answer 14

<4 hours after ingestion
limited data to support

Question 15

activated charcoal

Answer 15

porous carbo, effective absorbent
not effective for strong acids, alkalis, alcohols, cyanide, lithium, ethylene glycol, metal, bleach, xylitol
+/- cathartic sorbitol (accelerate defecation) electrolyte abnormalities/dehydration

2-5 g/kg when <1h post ingestion

Question 16

cholestyramine

Answer 16

bile acid sequestrant - binds to bile in GIT to prevent reabsorption
enterohepatic recirculation may have accelerated elimination from body
alternative to multidose activated charcoal

Question 17

what is the most common kinetics of toxins?

Answer 17

transformed in the liver, excreted through kidneys

Question 18

ion trapping

Answer 18

most drugs are weak acids or bases and ion trapping can be used to increase excretion rate
modifying the pH of a surrounding environment can trap a drug and prevent absorption
most commonly sed for drugs absorbed in nephron/bladder