DECONTAMINATION & MANAGEMENT

Question 1

General approach
to the toxicology patient
n Airway
n Breathing
n Circulation
n Decontamination
n Elimination
n Find an antidote
n General management

The Toxic Emergency
Components of Definitive Management

Answer 1

see slide 4

Question 2

SKIN

Answer 2

n Remove toxin from skin immediately to
decrease burns
n Flushing skin also prevents absorption of
agents readily absorbed by the skin systemic
absorption can be prevented
n Examples:
n Phenol – seizures, coma, hepatic & renal damage
n Methylene chloride – CNS depression, cardiac
dysrhythmias & is metabolized to carbon
monoxide

n Flush with copious amounts of water
n Remember behind ears, under the nails and in folds of skin
n Soap and shampoo can be used for oily substances
n Neutralize?
n Chemical neutralization can generate heat and potentially create worse injury

Want to remove it from skin
The longer you keep it on the higher chance of absorption
Flush with saline or water
Dont put acid if got an alkaline substance
Cna cause exothermic rxn
Best to use water, get in the shower

Question 3

EYES

Answer 3

n Corrosive agents rapidly damage corneal
surface and can cause permanent scarring
n Flush with tepid water or saline for minimum
15 min for most substances
n Remove contact lenses
n Check pH of eye to determine end point
n Again goal is not to neutralize!
n May cause heat and result in damage

Question 4

INHALATION

solule gases
less soluble

Answer 4

Irritating gases or fumes

Warning properties: irritation
n Some can be detected by smell or irritation
E.g. mixing cleaning agents
n Not always reliable: Olfactory fatigue (e.g.
H2S)

Soluble gases
n Examples: ammonia, chlorine
n Affect mucous membranes eye nose & throat

Less soluble phosgene, nitrogen
n Not readily absorbed can be inhaled deeply
into the lower respiratory tract, delayed onset
pulmonary toxicity

Question 5

Principles of Irritant Gases 101

Answer 5

n Water Solubility can
impact
n Location of
symptoms
n Likelihood of
detection
n Likelihood of
removal from area
n Onset of symptoms
n Risk of delayed
pulmonary edema

Water soluble - higher in resp tract
More likely to get out of the area

Question 6

Inhalational Exposure
Decontamination

Answer 6

n FRESH AIR!!
n Leave area *
n Open windows
n Fans
n Advise rescuers to protect themselves

Question 7

ingestion: Approach to GI
decontamination

Answer 7

n When was the exposure?
n What is the toxin?
n What is the potential lethality of the toxin?
n What is the patient’s clinical status at this time?
n What is the expected duration of symptoms?
n Is the toxin adsorbed to activated charcoal?
n Is there an antidote or other effective therapy for this
toxin?
n What decontamination options are available at my
facility?
n What decontamination options are my staff
comfortable with?

Question 8

GI Decontamination Options

Answer 8

n Gastric lavage
n Activated charcoal
-
Standard dose response curve
Low doses - ppl prob wont benefit from charcoal
More likely to get AE from the AC

Top of curve - large amt of lethal compound
No amount of AC is going to revive that person

Idea to hit them on the cusp before that and shift them down the curve to lower risk category
Decrease dose burden of drug taken
n Whole bowel irrigation

Question 9

IPECAC – Never Recommended.

Answer 9

n No longer the treatment of choice
n Delays the administration of charcoal
n ADRs
n Persistent vomiting, forceful vomiting and
damage
n Drowsiness 20% of children
n Diarrhea 25% of children

Question 10

GASTRIC LAVAGE -Rare

Answer 10

n Used in massive overdoses or particularly
toxic substances
n May be useful in agents that slow gastric
emptying (e.g. salicylates or antihistamines)
n Patient able to tolerate procedure
n Airway secure
n Lavage only occasionally used
Large no of tablets w toxic compounds

Slowed down gut
Put tube down and flush it w fluid
And suck back fluid to hope you get some of the drug
Airway must be secured
unpleasant

Question 11

Life Threatening Toxins Where
Lavage Might Be Considered

Answer 11

n Tricyclic antidepressants
n Salicylates
n Calcium channel blockers
n Beta blockers
n Colchicine
n Iron - Iron not bound by AC - may be used
But more likely WBI used
n Paraquat = Pesticide pretty deadly and aggressive to try to get it out

Question 12

Contraindications and Adverse Effects
of Lavage

Answer 12

n Contraindicated
n Comatose patient WITHOUT airway secured
n Convulsing patients
n Possible Adverse Effects
n Perforation of esophagus or stomach -If they ingested corrosive agent there is risk of puncturing the esoph lining
n Nose bleed (NG vs OG)
n Inadvertent tracheal intubation
n Vomiting/aspiration

Question 13

Lavage - Drawbacks

Answer 13

n Does not reliably remove un-dissolved pills
n Sustained release or enteric coated tablets
particularly difficult to remove
n Due to size of most, lavage is unlikely to return intact
tablets, even through a 40 french OG tube
n May delay use of charcoal
n Benefit decreases with time

Question 14

ACTIVATED CHARCOAL

Answer 14

Surface area of 1000m2/gm made from low
ash wood pulp broken down to fine granular
form activated by steam, oxygen, CO2
n Adsorbs most toxins and drugs
n Sometimes is given with poorly adsorbed
ingestants in case other substances ingested (Even if iron wont bind can give if theres concern of co-ingestant
With hopes of binding that compound)
n Likely works best if given within hours of
overdose BUT may be given later
n Few patients present to ED within first 60mins
n Ideally 10:1 charcoal:drug ratio (based on in
vitro studies) to limit absorption
n Common dose recommendation is 1g/kg PO
n Given for most toxins depending on the
exposure, but not all – iron and lithium among
common toxins not adsorbed

Question 15

Dispelling The 1 Hour Myth

Answer 15

“If it works at 59 minutes, there’s no reason it shouldn’t work at
61 minutes”
n ATOM2 – Can give AC up to 4 hours post ingestion in APAP
n New York City Poison Center and Office of Chief Medical Examiner:
n 9% of overdose autopsies had partially dissolved pills in stomach
n Many cases involved opioids, anticholinergics, salicylates, modified release preparations
n Bupropion was cause of death in 17/92 cases

Question 16

ATOM-2

Answer 16

Activated charcoal within 4 hrs. post-ingestion
(49 (25%) at median of 2 hrs. post-ingestion)
n Lower APAP ratio
n 1.4 vs 2.2
n Lower rates of hepatotoxicity

Question 17

ACTIVATED CHARCOAL -
Contraindications and Adverse Effects

Answer 17

n Contraindicated in drowsy patients
n Airway must be protected!
n Risk of pulmonary aspiration if vomiting
occurs
n Especially in drowsy patients
n ADR’s
n Constipation, impaction, bezoar especially
with multi doses

The more drowsy they are the more likely they will aspirate the charcoal

When it goes into lungs hard to get out and hard to breathe

The more drowsy they are the more likely they will aspirate the charcoal
When it goes into lungs hard to get out and hard to breathe
If pt sedated, need to be intubated and need to be given over NG tube
- Even this isn’t complete protection
Listen for bowel sounds after giving AC

Question 18

When might charcoal not be indicated
or be harmful?

Answer 18

n Substance isn’t bound/poorly bound to charcoal
n Heavy metals: lead, mercury, arsenic
n Iron
n Lithium
n Potassium
n Alcohols
n Cyanide*

charcoal contraindicated
n Acid/alkali ingestion (especially where endoscopy is
planned)
n Obtunded patients at risk for aspiration
n Intestinal obstruction
The elements not bound

Alcohols trad not bud, get absorbed quickly
Cyanide is debated - so poisonous that you might give it a shot, it might bind but up for debate
If ingested corrosive, need to see what type of damage is done to GI tract
Charcoal Black substance will obscure assessing the tissues

Question 19

CHARCOALAs an Elimination Strategy:

Answer 19

n Doses given >1 hour are sometimes
recommended to prevent ongoing absorption
of agents that persist in the GI tract
n Modified release preparations
n As an Elimination Strategy:
n Repeat doses can increase the rate of
elimination of some drugs
n Those that have a small volume of distribution
n Those that undergo enterohepatic or
enterogastric recirculation

Question 20

Multidose AC

Answer 20

Idea here w elimination is trying to enhance elim instead of prevent absorption

Ingest med - gets absorbed and does effect

Some drugs excreted thru bile from liver and then can go into gut to recirculate into vessels (anticonvulsants)
Give multiple AC to interrupt cycle and pick up the drugs excreted from bile and poop it out

Question 21

WHOLE BOWEL IRRIGATION

Answer 21

n Polyethylene glycol electrolyte solution
n Administer via NG until rectal effluent clear
n 2L/hr for adults
n 0.5L/hr for children

Rather than binding drug try to push it out the other end

Colyte and give quite a lot
Tastes bad, put it down NG tube
Give until rectal effluent is clear, whats going in looks like out

Question 22

INDICATIONS whole bowel irrigation

Answer 22

Consider for sustained release preparations or
for substances not bound to activated charcoal
n SR beta or calcium channel blockers
n Lithium
n Iron
n Body packers
n Lead object (i.e. lead bb’s)

Things not bound by AC
Body packers dont want it to burst inside GI
Try to flush it out ther end

AC doesnt bind lead
Push it out before lead is absorbed

Question 23

Bottom Line

Answer 23

n Decontamination can limit drug absorption
and therefore prevent toxicity
n Never induce vomiting
n Activated charcoal is the most frequently
utilized method of GI decontamination
n The main risks associated with AC is
aspiration
n Decisions are rarely black and white: Call
PADIS for help
n Whole Bowel Irrigation is another option
when AC is not appropriate