PEDIATRIC TOXICOLOGY - PowerPoint Presentation

Slide1

PEDIATRIC TOXICOLOGY

Badrinath

Narayan, PEM Fellow

Pediatric AHD, Aug 5

th

2014Slide2

PEDIATRIC TOXICOLOGY

Objectives

Provide a general approach to the poisoned patient

History, physical, investigations

Introduce types of decontamination with indications/complications

List “Pills that Kill”Slide3

Poisoning

Poisoning

One of the most common medical emergencies

Exploratory behaviour

Child abuse

Environmental exposures

Suicide attempts

In utero toxicants

Pediatricians have a role in advocacy

Modes of exposure:

Ingestion, ocular exposure, topical exposure, envenomation, inhalation and

transplacental

exposure. Slide4

Approach

Brief window of opportunity to make critical diagnostic and management decisions

Prioritize critical assessment and simultaneous management interventionsSlide5

14 year old female found unconscious in a park by friends

The

patient is brought into the trauma

bay

at BCCH ED

What would you do?Slide6

Primary Survey - ABCDEFG

Apply monitors

-

O2, HR, RR, cycling

BP

Obtain

vitals

: HR, RR, BP, O2

sat

A –

Maintain patency, assess reflexes, note GCS, have airway equipment ready

B

-

Apply O2

, consider ETCO2, ABG

C

– Assess perfusion,

Get

two large bore

I

v

s

D

isability (GCS, pupil size and reactivity), ? Signs of trauma

D

econtamination

D

rug Treatment – dextrose, oxygen,

narcan

Bedside

G

lucoseSlide7

Primary Survey

Pay special attention to:

Evidence of impaired airway protective reflexes

Many poisoned patients will vomit

Elective endotracheal intubation may be indicated at a lower threshold

Anticipate imminent respiratory failure

Cyanosis/apnea are late findingsSlide8

Case

The patient has been stabilized

What would you ask?Slide9

History

– known intoxicant

Take

standard AMPLE history plus

:

What was ingested, How much, When, Why?

Obtain prescription bottles when possible, and be sure that bottles contain med listed

Talk to patient’s family and friends in ED/contact home

Ensure belongings are looked at to identify paraphernalia

In a toddler think single pills, in an adolescent think co-ingestions!!Slide10

When to suspect?

Suspected but unknown intoxicant:

Acute onset of illness

Pica-prone age (1-5)

History of pica, ingestions

Current household “stress”

Significantly altered mental status

Family medications/recent illnesses

Social: grandparents visiting, holiday parties, other eventsSlide11

Case

On exam what things might you see to suggest a toxicological cause for the child’s presentation?Slide12

Physical

Vitals

GCS/mental status

Pupils, EOM, fundi

Mouth: corrosive lesions, odors, secretions

Respiratory: rate, chest excursion, air entry

CVS: rate, rhythm, perfusion

GI: motility, corrosive effects

Skin

colour

, burns,

diaphorsis

,

piloerection

, track marks

Bladder sizeSlide13

OdoursSlide14

Removal of toxic substance

De

contami

nation

:

Removal of a substance prior to entry into the circulation

Elimination

:

Removal of a substance by enhanced excretion once it has entered the circulationSlide15

Approach

to decontamination

Get help -- Poison control centre

24-hour Line: 604-682-5050 or 1-800-567-8911

Healthcare professionals only line:

604-707-2787 or 1-866-298-5909 (outside the Lower Mainland)

Monday to Friday from 9 am - 4 pmSlide16

Forms of Decontamination

Topical

flush

aggressively

(ocular or skin)

,

remove contaminated

clothing

Dilution

Ipecac

(no longer recommended; AAP statement against it)

Activated Charcoal

Gastric

Lavage

– also fallen out of favour

Whole Bowel IrrigationSlide17

Dilution

Indicated if toxin produces only simple irritation

Controversial for caustic agents

May be used in first few minutes

NOT for drugs – may increase absorption

Not if upper airway compromise

Water or milk

E.g. dish soapSlide18

Activated Charcoal

“Activation” increases surface area of particles

Toxins adsorb to activated charcoal decreasing amount adsorbed by the body

Some toxins are not well adsorbed – most small molecules

Iron, the alcohols, lithium, strong acids and alkali, sodium, chloride.

Dose: 10:1 charcoal to drug ratio.

For unknown ingestions dosing is based on ability to tolerate the agent: Children - 1 gram/kg of body weight.Slide19

Activated Charcoal

Timing

If not contraindicated there does not seem to be a reasonable time that is too late to give AC, especially with SR or DR products

Dogma used to be an hour but studies with respect to delayed gastric emptying have challenged this data

Multiple-dose activated

charcoal

sustained-release products

useful with drugs with low

Vd

, low protein binding, long half-

lifeSlide20

Activated Charcoal

Activated charcoal not useful with:

P

esticides

H

ydrocarbons

A

cids, Alkali, Alcohols

I

ron

L

ithium, Liquids

S

olventsSlide21

Activated Charcoal

Contraindications

absent gut motility or perforation

if endoscopic visualization is required (e.g. caustic ingestions)

loss of protective airway reflexes

Complications

fatal aspiration

small bowel obstructionSlide22

Gastric Lavage

Orogastric lavage with a large bore tube (36-40 F for adult; no smaller than 22-24 F for children)

RARELY recommended – not been demonstrated to improve outcome, several risks

Might be considered: VERY early or after very dangerous ingestions (colchicine, arsenic)

Ensure

airway protected

Place patient in left lateral decubitus position with the head down

Have suction available for secretions

Place tube (tragus-nose-xyphoid) and confirm position

Lavage until fluids clearSlide23

Whole Bowel Irrigation

Whole bowel irrigation of the entire GI tract by instillation of large volumes of

fluid

Usually takes hours

Has

been used safely in children

Most useful for substances

with delayed absorption ( i.e. extended release ),

not

amenable to activated charcoal and with body stuffers/packersSlide24

Whole Bowel Irrigation

Accomplished by orally taking (or through NG) large volumes of Nulytely (approved for children and adults), Colyte, or Golytely

Ad

olescents

:

mininum of 1.5-2 L/hour

Children:

25

mL/kg/h

Give until rectal effluent is clear.Slide25

Whole Bowel Irrigation

Contraindications:

absent bowel sounds

bowel obstruction or perforation

unprotected compromised airway

hemodynamic instabilitySlide26

Forms of Elimination

Urine

alkalinization

- promotes excretion of salicylate, enhances clearance of some drugs

Dialysis

Charcoal HemoperfusionSlide27

Dialysis

Consider nephrology consult with dialysis if:

S

alicylates

T

heophylline

U

remia

M

ethanol

B

arbiturates

L

ithium

E

thylene GlycolSlide28

Antidotes

Poison

Antidote

Acetaminophen

N-acetylcysteine

Anticholinergics

Physostigmine

Cholinergics

Atropine

Benzodiazepines

Flumazenil

Carbon monoxide

Oxygen

Cyanide

Amyl nitrite, sodium nitrite, sodium thiosulfate, hydroxycobalamin

Digoxin

Digoxin-specific Antibodies

Ethylene glycol

Ethanol/fomepizole, thiamine and pyridoxine

Poison

Antidote

Heavy metals

Dimercaprol (BAL), EDTA, penicillamine

Hypoglycemic agents

Dextrose, sucrose, octreotide

Iron

Deferoxamine mesylate

Isoniazid

Pyridoxine

Methanol

Ethanol/fomepizole, folic acid

Methemoglobinemia

Methylene blue

Opioids

Naloxone

Organophosphates

Atropine, pralidoxamine

Avoid

physostigmine

if TCA ingestion present - has potential to worsen ventricular conduction defects and to lower seizure threshold.Slide29

Investigations

Select tests

only

Help confirm

diagnosis

Help monitor

Help identify “silent” killers

Tox

screens

not useful

in acute

managementSlide30

Investigations

All symptomatic patients with unknown ingestion should get electrolytes, glucose, osmolarity, acetaminophen/ASA levels, blood gas, EKG

All suicidal patients should get acetaminophen level (~1:500 patients without a history of APAP ingestion will have a potentially toxic blood level - NYPCC

)

and ASA level

Other tests based on history, physical, level of

suspicion

CBC

Specific drug levels

Urinanalysis

BHCG

Calcium, liver function panelSlide31

I

ncreased anion gap metabolic acidosis

(Na – (

Cl

+ HCO3)

M

ethanol

(

hx

of alcohol abuse, methanol level)

,

metformin

U

remia

(BUN)

D

KA,

AKA

, SKA (

hx

; urine ketones)

P

araldehyde

(distinctive

odor

)

I

soniazid

(seizure; lactate level)

L

actic

acidosis

E

thylene

glycol

(level)

S

alicylates

/solvents (level)Slide32

Increased

Osmolar

gap (serum – calculated)

“Two salts and a sticky BUN”

M

annitol

A

lcohols

D

ye

G

lycerol

A

cetone

S

orbitolSlide33

Pitfalls of osmolar

gap

Cannot distinguish between type of toxic alcohol

I

nsensitive in late presentations

Not sufficiently sensitive to exclude small ingestion

Cannot rule out ingestion based on a normal OGSlide34

Radio-opaque drugs

Chloral Hydrate

Opioid packets (latex)

Iron and other heavy metals

Neuroleptics

Sustained release tablets/SalicylatesSlide35

ECG

Findings include:

Toxicologic

tachcyardia

/

bradycardia

QRS widening

Prolonged QT (

www.qtdrugs.org)

Findings can develop late so obtain serial ECGsSlide36

Case

A 2 year old girl is found playing with his grandmother’s pill box. Some pills may be missing and a powder residue is found in the child’s mouth.

What medications would most concern you if this child ate “just one pill”?Slide37

Small dose toxins

Substance

Major symptom

Symptom onset

Medications

Beta-adrenergic antagonists(sustained release)

Bradycardia

, hypotension

Delayed, up to 24 hours

Buproprion

(sustained release)

Seizure, cardiovascular collapse

Delayed up to 24 hours

CCB (sustained release)

Bradycardia

, hypotension

dElayed

, up to 24 hours

Clonidine

Apnea,

bradycardia

, hypotension

1-2 hours

Lomotil

(

Diphenoxylate

/Atropine)

Apnea

Delayed, up to 24 hours

Methylsalicylate

(oil of wintergreen)

Metabolic acidosis, pulmonary/cerebral edema

1-6 hours

Opioids: extended release preparations

Apnea

Delayed, up

to 24 hours

Methadone

1 – 2 hours

Sulfonylureas

Hypoglycemia

Delayed,

up to 24 hours

Theophylline

Seizure,

hypotension

Delayed, up to 24 hours

Other

agents

Camphor

Seizure

Minutes to hours

Pesticides

SLUDGE

Minutes to hours

Toxic alcohols

Blindness, renal failure, metabolic acidosis3 – 8 hours (ethylene glycol)3 – 18 hours( methanol)ONE PILL KILLERSSlide38

Case

A 3

yo

male presents to the ED comatose with a GCS of 6. He was found on the bathroom floor. Following stabilization, what is the most immediate course of action?

A. Head CT

B. ECG

C.

Tox

screen

D. Broad spectrum

Abx