TOXICOLOGYThe only difference between

medicine and poison is the dose.

Poisoning basic facts Approximately 47.8 percent of the poison exposure calls handled

by the IPC in 2012 involved children ages 5 and under. Poisonings are usually unintentional in children less than 5 years

old. Intentional poisonings usually seek treatment at a higher rate in

comparison to people who have been unintentionally poisoned. Adults/adolescents most often present with ingestion of

psychopharmacologic drugs; in comparison younger children tend to present with ingestion of household products, plants, cleaning agents, medication, or vitamins.

Toxicology and the EDWhat drug?What route?What dose?What age of the patient?What time was the event?What symptoms?

Pathophysiology…

Primarily look at effects of the nervous systemSympathetic nervous system (fight or flight

response)Symptoms can include tachycardia, pupil

dilation, increased cardiac output, peripheral vasoconstriction, bronchodilation

Toxins include adrenergics and stimulants such as meth, cocaine, caffeine (ex. Nodoz pills), epinephrine (ex. Epi-pen)

Pathophysiology… cont.Sympathetic blockersPrimarily going to be your beta blockers (-olol

drugs)Symptoms going to be decreased blood

pressure, decreased heart rate, look for signs of decreased perfusion and shock.

Pathophysiology… the other half

Parasympathetic nervous system (rest and digest)Functions in opposition to the sympathetic nervous

system.Symptoms based on the type of receptor involved, either

muscarine or nicotine. Muscarine receptors result in miosis (pupil

constriction), vasodilation, bradycardia, decreased cardiac output, bronchorrhea (sputum), increased gut motility, micturition (urination), and sweating. (Think S.L.U.D.G.E.)

Nicotine receptors result in fasciculations (mini twitches), weakness, paralysis, tachycardia, and hypertension.

Pathophysiology… the final chapter

Anticholinergics! (aka I wish I was a stimulant but I can’t quite cut it) Examples include Atropine, belladonna alkaloids, shrooms

(some), tricyclic antidepressants, and OTC sleep meds Presentation includes Hot(hyperthermia), Crazy

(hallucinations), Blind (dilated pupils), Dry (dry mucous membranes), Red (flushed skin), basically you get a red, febrile, hallucinating person who can’t see and really wants a drink

The difference between anticholinergics and stimulants is peristalsis remains decreased and the skin remains dry in this situation.

Primary AssessmentAssessment always begins with the initial

impression, if you get the sinking feeling in your gut there is probably a reason…ABC’s with immediate interventionAirway, is it open, can the patient protect it on their

own?Breathing, are they breathing on their own, do you have

to assist?Circulation, do they have a radial pulse? Are they

diaphoretic, tachy?Disability (Neuro) Fast GCS, remember AVPUExpose, signs of trauma, route of administration, is

there toxin on clothes/skin. Don’t forget to flip and look at the back if needed.

Secondary AssessmentFull set of vitalsGive comfort (meds, blankets, breathing for them…)History, medical and events. This can include chief

complaint in the chart, don’t forget EMS can be a great source of information.

RETURN TO PRIMARY ASSESSMENT IF NEEDED!E.g. If they stop breathing don’t continue with

the history taking, it can wait.Nursing is a constant state of motion, once you finish your

primary/secondary start over and look for changes.

Interventions**Decontamination for exposure; before anything or you will end up in the same boat as the patient (with any luck this was done in the field)Airway: repositioning, oral/nasal airway, ET tube, SPO2

sensorBreathing: Oxygen (nasal cannula or mask), Ambu bag,

vent (CXR for aspiration during the course of the stay)Circulation: IV(s), lab work (CBC, CMP, Tylenol, ASA,

ETOH, UDS), fluids, med administration (including reversal agents if applicable), cardiac monitor, BP reading.

Maintain Control (of self and others)Provide support to patient and family as applicable.Suicide risk assessment and safety screening

Interventions: PrimaryActivated Charcoal

Generally indicated for ingestion with known time in the previous hour. Some cases may have this given after that time window.

Reversal agentsRomazicon for benzodiazepines, Narcan for

opiatesLast drug given is first drug reversedRomazicon can cause seizure in people who

take large or increasing dosed of benzodiazepines

Reversal can simply be airway maintenance and time

Interventions: Primary cont.Dermal Decontamination

strip off contaminated clothes, rinse with large amounts of water

Ocular Decontamination (Morgan Lens) usually connected to 0.9% NS and irrigating to

gravity. Consider use of numbing agent prior to insertion of Morgan Lens

Interventions: SecondaryThese are the less often used interventionsGastric LavageForced Diuresis 3-6 ml/kg/hour NS Alkalinization (antifreeze ingestion)Hemodialysis (non-reversable toxic level

situations)

Specific agent situations

Caustics/CorrosivesExamples include Cleaning Agents, Bleach,

Pool chemicalsSymptoms – Oral or facial burns, Drooling,

Dyspnea or StridorAny indication of airway involvement should be

addressed immediatelyIntervention – Dilution, Irrigation

Avoid Emesis (if it burns going down it will burn coming back up)

Activated charcoal not indicated in this case

HydrocarbonsSolvents & FuelsSymptoms – Odor!Intervention – Dilution or Decontamination

Avoid Emesis, can cause aspiration however absorption of ingested substance can lead to toxic levels.

Charcoal is ineffective.Inhaled affects the neural systemIngested affects the pulmonary system,

resulting in pulmonary edema and pneumothorax

High risk for aspiration pneumonitis which can be fatal

AcetaminophenPrimary affect is Hepatic Damage (long term)2-4 Hour Half-lifeSevere Toxicity >10 gramsMucomist (Acetylcysteine) used for hepatic

protectionSerum level available from Lab

SalicylatesMixed respiratory alkalosis, metabolic

acidosisBody attempts to correct metabolic acidosis with a

respiratory alkalosis resulting in mixed stateToxicity >250mg/kgInterventions -

Bicarb/K+/Charcoal/CoolingDialysis if Severe

Tricyclic AntidepressantsCommon are amitriptyline & DoxepinAnticholinergic Long Half-life, patient can present decently and

deteriorate during course of treatmentPresentation: Altered Mentation, tachy

dysrhythmias, potential for seizureInterventions-IVF, airway maintenance,

continuous monitoringTreatment focused on individual symptomsAtropine not viable for brady arrhythmias due to

anticholinergic properties

SSRIsCommon ones include: citalopram (celexa),

escitalopram (lexapro), fluoxetine (prozac), paroxetine (paxil), sertraline (zoloft)

Serotonin Syndrome: Muscle rigidity, myoclonus (uncontrolled twitching), hyperthermia, AMS, incoordination, hyper-reflexia, coma

Treatment: Activated charcoal, symptomatic/supportive treatmentMay result in liver failure due to hepatic

metabolization

IronTypically from vitamins, pre-natal have sepecially

high amounts of ironPresentation – based on stages

Stage I: (30 min to 6 hrs post ingestion) Nausea, vomiting, abd pain, hematemesis

Stage II: (6-12 hrs) May see temporary improvement, does not always occur

Stage III: (12+ hrs) Metabolic acidosis, circulatory failure, CNS depression/coma, hepatic failure

Stage IV; (1-2 months) gastric scarring and stricture

Tx – Whole Bowel Irrigation/Deferoxamine

Ethanol… (this is where we say “never drink like that again”)

Protect Airway (they vomit and aspirate), include Cardiac Monitor and SPO2Typically also present with orientation issues,

may get out of bed and fall furthering injurySensation of pain altered, unable to report well

CNS and Respiratory DepressantHypoglycemiaAlcoholics Need Thiamine

Methanol & Ethylene Glycol(antifreeze)

Presentation – altered mental status, may appear like alcohol intoxication. Potential for dysrhythmias, seizure.Un-metabolized form nephrotoxic, metabolized

form results in metabolic acidosisMetabolic acidosis and concurrent cerebral

edemaTreatment – Ethanol/Fomepizole as

competition for metabolism, Bicarb to assist in reversal of acidosisHemodialysis in severe cases

Sedative HypnoticsBenzodiazepines/BarbituratesPresentation - Altered mental status,

hypotension/shockIntervention – Airway management

Consider Romazecon, be aware of seizure potential. Unable to medicate seizure if romazecon administered

Opiates & NarcoticsPresentation – Constricted Pupils, altered

mental status, bradycardia, hypotension, bradypnea/apnea

CNS & Respiratory DepressionAirway management, potential for emesis and

aspirationReversal agent = Narcan

PsychostimulantsCocaine, Meth, pseudoephedrine,

amphetamine salts (e.g. ADD meds)Presentation: CNS Stimulant (tachy pnea,

tachycardia), Manic or Paranoid, hypertension, seizure, Dysrythmias (can result in MI or CVA in younger population)

Interventions – Cardiac Monitor, Charcoal, Haldol, Cooling, Seizure Precautions

Questions?

Referenceshttp://illinoispoisoncenter.org/Illinois_Poison_Center_Fact_Sheet

ENA Orientation to Emergency Nursing Toxicology chapter, 2000.