TOXICOLOGYAn Overview

Jordan B. Barnett, M.D., FACEPJordan B. Barnett, M.D., FACEPInterim Director, Department of Emergency Interim Director, Department of Emergency

MedicineMedicineEpiscopal HospitalEpiscopal Hospital

POISONING

Estimated 4 Million AnnualPediatric

Child AbuseAdult

RecreationalSuicide

HISTORY

What Poison?How Much?How?When?Why?What Else Taken?

PHYSICAL EXAM

Vital SignsABC’sTemperature

Toxic Syndrome Respiratory Cardiovascular Neurologic

TREATMENT

ABC’s Treat Other Injuries Decontamination Supportive Care Definitive Care

AntidotesElimination

DECONTAMINATION: IPECAC

Absorption Reduced By 30% Interferes With Further

Decontamination Interferes With Further Treatment Home UseNO EMERGENCY DEPARTMENT

USE!

DECONTAMINATION:GASTRIC LAVAGE

250 - 300 cc Aliquots Of Fluid 36 - 40F Tube Advantages

Immediate Recovery Of Gastric ContentsDirect access For Charcoal Instillation

Left Lateral Decubitus With Trendelenburg

Intubation May Be Needed

DECONTAMINATION:GASTRIC LAVAGE

Disadvantages Not Complete Gastric Emptying 30% Recovery At 1 Hour Labor Intensive Complications

3% Overall Esophageal Rupture Aspiration Hypoxia

DECONTAMINATION:CHARCOAL

Not Absorbed From GI Tract Binds Most Substances Prevents Absorption Enhance Excretion

Multiple DoseEnterohepatic Circulation

DECONTAMINATION:CHARCOAL

CharcoalCharcoalEmesisEmesisLavageLavage

57%57%38%38%32%32%

Ampicillin ModelDecreased Absorption

ACTIVATED CHARCOAL

Dose 1g/kgDose 1g/kg Repeat DoseRepeat Dose DisadvantagesDisadvantages

MessyMessy AspirationAspiration

SUBSTANCES NOT BOUND BY CHARCOAL

Alcohols And Alcohols And GlycolsGlycols

CorrosivesCorrosives AlkalisAlkalis AcidsAcids

CyanideCyanide Saline CatharticsSaline Cathartics

Heavy MetalsHeavy Metals IronIron LeadLead LithiumLithium MercuryMercury

HydrocarbonsHydrocarbons

CATHARTICS

Mechanism Types Mixture With Charcoal Disadvantages Use In Children

OTHER MODALITIES

Whole Bowel Irrigation IndicationsTechnique

Skin Eye

RESPIRATORY COMPLICATIONS

Airway Protection Ventilatory Insufficiency Bronchospasm Noncardiogenic Pulmonary Edema Aspiration

CARDIOVASCULAR COMPLICATIONS

Tachycardia Bradycardia Hypotension Hypertension

NEUROLOGIC COMPLICATIONS

Coma Seizures Behavioral Abnormalities

DIAGNOSTIC STUDIES

Drug Screens/Levels Acetaminophen ABG Electrolytes Organ Function EKG X-RAY

SERUM OSMOLARITY

Serum Osmolarity= 2 (Na+) + BUN/2.8 + Glucose/18

Osmolar Gap 10 mOsm or less Methanol, Ethylene Glycol, Ethanol Glycerol, Mannitol +ETOH/4.6

ETHANOL

C2H5OHMolecular Weight=________

DEFINITIVE CARE

Decontamination Supportive Care Antidotes

Oxygen/Glucose/Narcan/?Flumazenil Elimination

AlkalinizationRepeated Dose Charcoal

Dialysis

DISCHARGE

Stable In Emergency Department Psychiatric Issues

TOXIDROME

Toxic Syndromes

TOXIDROMES: CASE 1

25 Year Old PA Student Just Back From Spring Break In Mexico. He's Been Having Terrible Diarrhea Since Returning and Has Been Using Pills to Alleviate the Symptoms.

TOXIDROMES: CASE 1

Dry Skin And Mucous Membranes Thirst Blurred Vision Fixed Dilated Pupils Flushing Urinary Urgency And Retention Hallucinations

TOXIDROMES: CASE 1

AnticholinergicHot As HadesBlind As A BatDry As A BoneRed As A BeetMad As A Hatter

TOXIDROMES: CASE 1

Belladonna AlkaloidsAtropine/ScopolamineScopolamine

Synthetic AnticholinergicsDicyclomine

OtherAntihistamines/Phenothiazines/TCA

TOXIDROMES: CASE 2

A 50 Year Old Farmer Is Found Unresponsive at His Barn.

TOXIDROMES: CASE 2

Sweating Constricted Pupils Lacrimation Excessive Salivation Wheezing Vomiting/Diarrhea Fasiculations

TOXIDROMES: CASE 2

Acetylcholinesterase Inhibitors Pesticides

Organophosphate Carbamates

Mechanism Treatment

Atropine Pralidoxime (2-PAM)

TOXIDROMES: CASE 3

An 8 Year Old Child Is Brought to the Emergency Department After Being Given a Compazine Suppository for Vomiting.

TOXIDROMES: CASE 3

Dysphonia Oculogyric Crises Rigidity Torticollis/Opisthotonos

TOXIDROMES: CASE 3

Extrapyramidal EffectsMedications

AntipsychoticAntiemetic

Treatment

TOXIDROMES: CASE 4

During a Visit to Grandma in the Nursing Home, You Find That You Can Not Wake Her Up.

TOXIDROMES: CASE 4

CNS DepressionPinpoint PupilsSlowed RespirationsHypotension

TOXIDROMES: CASE 4

NarcoticNarcoticMedicationsMedications

PrescribedPrescribedIllicit

TreatmentTreatment

TOXIDROMES: CASE 5

A Movie Star Presents to Your Hospital.

TOXIDROMES: CASE 5

CNS ExcitationSeizuresHypertensionTachycardia

TOXIDROMES: CASE 5

SympathomimeticMedication

PrescribedIllicit

Treatment

TOXIDROMES: CASE 6

A Family of 6 Presents to Your Office in the Middle of Winter and All Complain of “the Flu”.

TOXIDROMES: CASE 6

Headache “Flu” Symptoms Nausea, Vomiting, Dizziness Dyspnea Seizures Death Cyanosis “Chocolate” Blood

TOXIDROMES: CASE 6

HemoglobinopathiesCarbon MonoxideMethemoglobinTreatment

TRICYCLIC ANTIDEPRESSANTS

Mortality 2 - 5 PercentLow Therapeutic/Toxic RatioMechanism

Inhibition Of Amine UptakeAnticholinergicAlpha Receptor BlockerSodium Channel Blockade

TCACLINICAL FEATURES

Anticholinergic SymptomsTachycardiaCNS ToxicityComaHypotensionArrhythmiaSeizures

TCACLINICAL FEATURES

ECG“right axis deviation of the terminal

40ms of QRS greater than 1200 “Sinus Tach-Wide QRS-Decreased

Inotropy-Increased PRI-BradycardiaWide QRS=Life Threatening Toxicity

TCATREATMENT

GI Decontamination Sodium Bicarbonate-Indications

QRS WideningHypotensionVentricular Arrhythmias

Sodium Bicarbonate-Mechanism 1 - 2 mEq/Kg To pH 7.50-7.55

TCATREATMENT

PhysostigminePeripheral Anticholinergic SymptomsAgitation/Seizures/Hypotension When

Other Methods FailSide Effects

SeizuresBenzodiazepines/Barbiturates

Hypotension

SALICYLATES

Gastroenteritis Mixed Respiratory And Metabolic

Acidosis CNS Cardiac Toxicity Pulmonary

ARDS Tinnitus

SALICYLATESTOXIC DOSE

Done Nomogram Acute, Single Ingestion Cannot Use For:

Acute Ingestion With Salicylate Taken Within Last 24 Hours

Chronic Salicylate Poisoning Ingestion Of Enteric Coated Tablets

Treat Patient If Symptomatic

SALICYLATESTREATMENT

Charcoal IV Fluids Urine Alkalinization

Mechanism “Ion Trapping” Un-ionized Salicylate Reabsorbed By Renal

Tubules Alkaline Urine Favors Ionized Salicylate Which

Cannot Be Reabsorbed Dialysis

SALICYLATESDISPOSITION

Asymptomatic Nomogram After 6 Hours

Patient Asymptomatic Enteric Coated

150 mg/kg Psychiatric Evaluation Follow-up