chemical weapon exposures management in the ed suj sivaraman r3 emergency medicine mcgill university
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Chemical Weapon ExposuresChemical Weapon Exposures
Management in the EDManagement in the ED
Suj SivaramanSuj Sivaraman
R3 Emergency MedicineR3 Emergency Medicine
McGill UniversityMcGill University
October 23, 2002
50 Chechen rebels, storm 50 Chechen rebels, storm Moscow’s House of Culture Moscow’s House of Culture Theatre during a performance Theatre during a performance of Nord-Ost, taking 700 of Nord-Ost, taking 700 hostages. The rebels demand hostages. The rebels demand Russian withdrawal from Russian withdrawal from Chechnya, and threaten to kill Chechnya, and threaten to kill the hostages if demands are the hostages if demands are not met. not met.
TV footage from inside the TV footage from inside the shows that the rebels have shows that the rebels have explosives strapped to their explosives strapped to their bodies as well as throughout bodies as well as throughout the theatrethe theatre
October 26, 2002October 26, 2002
After three days of fruitless After three days of fruitless negotiations an unknown negotiations an unknown gas, meant to incapacitate gas, meant to incapacitate the rebels, is released in the rebels, is released in the theatre. Most of the the theatre. Most of the rebels and 116 hostages rebels and 116 hostages die.die.
What kind of gas was released? …What kind of gas was released? …
Chemical WeaponChemical Weapon
““A chemical substance which is A chemical substance which is intended for use in military intended for use in military operations to kill, seriously operations to kill, seriously injure or incapacitate people injure or incapacitate people because of it’s physiologic because of it’s physiologic effects”effects”NATO. Handbook on medical aspects of NBC defensive NATO. Handbook on medical aspects of NBC defensive operations (1996)operations (1996)
OverviewOverview
General Management PrinciplesGeneral Management Principles
Nerve AgentsNerve Agents
Pulmonary AgentsPulmonary Agents
VesicantsVesicants
Incapacitating AgentsIncapacitating Agents
Pre-Hospital CarePre-Hospital Care
Managing Hazardous Material Incidents. Managing Hazardous Material Incidents.
Agency for Toxic Substances and Disease Registry, Center for Agency for Toxic Substances and Disease Registry, Center for Disease Control, 2001Disease Control, 2001
Decontamination ZonesDecontamination Zones
Hot ZoneHot Zone– Respiratory Protection: Respiratory Protection:
Pressure-demand, self-Pressure-demand, self-containedcontained breathing breathing apparatus (SCBA) should apparatus (SCBA) should be used in all responsebe used in all response situations.situations.
– Skin Protection: Skin Protection: Chemical-Chemical-protective clothing should protective clothing should be wornbe worn when local and when local and systemic effects are systemic effects are unknown.unknown.
– Basic ABCsBasic ABCs
HAZMAT Suit Santa Clara Ca, Fire Dept.
Warm Zone Warm Zone (decontamination)(decontamination)– Victims exposed only to Victims exposed only to
gas or vapogas or vapouurs who rs who have no skin or eyehave no skin or eye irritation may be irritation may be transferred immediately transferred immediately to the Support Zone.to the Support Zone.
– All others undergo All others undergo basic decontaminationbasic decontamination
Emergency Response Decon Unit Union County, NJ
DecontaminationDecontamination Patients who are Patients who are
able and able and cooperative may cooperative may assist with theirassist with their own own decontamination. decontamination.
Remove and Remove and double-bag double-bag contaminatedcontaminated clothing and clothing and personal personal belongings.belongings.
Casualty Care research Center, Uniformed Services University, Bethesda, MD
Flush exposed or irritated skin Flush exposed or irritated skin and hair with plain waterand hair with plain water,, mild mild soap, soap, for 3 tofor 3 to 5 minutes.5 minutes.
Flush exposed or irritated eyes Flush exposed or irritated eyes with plain water or saline for atwith plain water or saline for at least 5 minutes. least 5 minutes. – Remove contact lenses if present Remove contact lenses if present
and easilyand easily removable without removable without additional trauma to the eye. additional trauma to the eye.
In cases of ingestion, do not In cases of ingestion, do not induceinduce emesis.emesis.– AdministerAdminister 4 to 84 to 8 ounces of water ounces of water
to dilute stomach contents if the to dilute stomach contents if the patient ispatient is alert. alert. HAZMAT Shower
Emergency Medical Products Inc.
Cold (support) zoneCold (support) zone– Be certain that victims have been Be certain that victims have been
decontaminated properly decontaminated properly – Victims who have undergoneVictims who have undergone
decontamination or who have been decontamination or who have been exposed only to gas orexposed only to gas or vapovapouur and who r and who have no evidence of skin or eye irritationhave no evidence of skin or eye irritation generally pose no serious risks of generally pose no serious risks of secondary contamination. secondary contamination.
– PPersonnel require no specializedersonnel require no specialized protective protective gear.gear.
ED Management PrinciplesED Management Principles
Emergency Room Procedures in Chemical HazardEmergency Room Procedures in Chemical Hazard EmergenciesEmergencies: : CDC National Centre for Environmental Health, November 2002 CDC National Centre for Environmental Health, November 2002
PreparationPreparation 1. Try to determine agent identity. 1. Try to determine agent identity. 2. Break out personal protection equipment, decon 2. Break out personal protection equipment, decon
supplies, antidotes, etc. supplies, antidotes, etc. 3. Don personal protective equipment3. Don personal protective equipment, s, set up hotline. et up hotline. 4. Clear and secure all areas which could become 4. Clear and secure all areas which could become
contaminated.contaminated. 5. Prepare to or secure hospital entrances and 5. Prepare to or secure hospital entrances and
grounds.grounds. 6. Notify local emergency management authorities if 6. Notify local emergency management authorities if
needed.needed. 77. If an organophosphate is involved, notify hospital . If an organophosphate is involved, notify hospital
pharmacy that large amounts of atropine and 2-PAM pharmacy that large amounts of atropine and 2-PAM may be needed.may be needed.
When the victim arrives …When the victim arrives … 88. Does chemical hazard exist? . Does chemical hazard exist?
– Known release/exposure (including late notification) Known release/exposure (including late notification) – Liquid on victim's skin or clothingLiquid on victim's skin or clothing– Symptoms in victim, EMTs, othersSymptoms in victim, EMTs, others– Odour (H, L, phosgene, chlorine) Odour (H, L, phosgene, chlorine)
99. Hold victim outside until preparations are completed. Hold victim outside until preparations are completed
1100. If patient is grossly contaminated OR if there is any suspicion . If patient is grossly contaminated OR if there is any suspicion of contamination, decontaminate patient before entry into buildingof contamination, decontaminate patient before entry into building in isolated decontamination areain isolated decontamination area
General measuresGeneral measures ABCsABCs Skin Exposure Skin Exposure
– If chemical burns are present, treat as thermal burns.If chemical burns are present, treat as thermal burns.
Eye ExposureEye Exposure– Ensure that adequate eye irrigation has been completed. Ensure that adequate eye irrigation has been completed. – TestTest visual acuity. visual acuity. – SSlit lamplit lamp– FFluorescein stain. luorescein stain. – Ophthalmology Ophthalmology for patients who have severe corneal for patients who have severe corneal
injuries.injuries.
Ingestion ExposureIngestion Exposure – Do not induce emesis. If alert administer activated charcoal.Do not induce emesis. If alert administer activated charcoal.– If a corrosive material is suspected, administer 4 to 8 ounces If a corrosive material is suspected, administer 4 to 8 ounces
ofof water do not givewater do not give activated charcoal. Consideractivated charcoal. Consider endoscopy endoscopy – If a large dose has been ingested and the patient’s condition If a large dose has been ingested and the patient’s condition
isis evaluated within 30 minutes after ingestion, consider evaluated within 30 minutes after ingestion, consider gastricgastric lavage.lavage.
Inhalation Exposure Inhalation Exposure – SSupplemental oxygen upplemental oxygen – BBronchodilatorsronchodilators if bronchospastic if bronchospastic
InvestigationsInvestigations CBC, glucose, and electrolyteCBC, glucose, and electrolytes, renal, LFTss, renal, LFTs ECGECG,, cardiac cardiac monitoringmonitoring Chest radiographyChest radiography, , pulse oximetrypulse oximetry, ABG if inhalation , ABG if inhalation
exposureexposure
Nerve Agents
Nerve AgentsNerve Agents Organophosphate compounds discovered in 1936 by Organophosphate compounds discovered in 1936 by
Gerhard Schrader (IG Farben, Germany) while Gerhard Schrader (IG Farben, Germany) while researching organophosphate pesticidesresearching organophosphate pesticides
Never used in WWII, but after the war the Soviets, Never used in WWII, but after the war the Soviets, U.K., and U.S. began pursuing nerve agent researchU.K., and U.S. began pursuing nerve agent research
1980-88: During Iran-Iraq War, Iraq thought to have 1980-88: During Iran-Iraq War, Iraq thought to have used nerve agents against Iran and Iraqi Kurdsused nerve agents against Iran and Iraqi Kurds
March 1995: Japanese Aum Shinrykio cult used March 1995: Japanese Aum Shinrykio cult used Sarin gas in Tokyo underground resulting in 5,500 Sarin gas in Tokyo underground resulting in 5,500 casualties and killing 12casualties and killing 12
Nerve AgentsNerve Agents The G-series:The G-series:
Taban (GA)Taban (GA)
Sarin (GB)Sarin (GB)
Soman (GD)Soman (GD)
The V-series:The V-series:VXVX
At room temp amber to colourless liquid state Weak fruity (G) to fishy (VX) smell G-series more volatile (sarin) than V-series V-series more toxic
Mechanism of actionMechanism of action
Normal Neurotransmission
Mechanism of actionMechanism of action
Nerve agent effects
Signs and SymptomsSigns and Symptoms
AChE inhibitionAChE inhibition
Cholinergic hyperstimulationCholinergic hyperstimulation
Cholinergic toxidromeCholinergic toxidrome
Signs and SymptomsSigns and Symptoms
Vapour Exposure
Eyes
Nose
Oral
Airways
Miosis, eye pain, headache,injection, lacrimation
Rhinorrhea
Salivation
Bronchoconstriction, bronchorrhea
Seconds to minutes after exposure
Signs and SymptomsSigns and Symptoms
Liquid Exposure
Skin
GI
Localized sweating, fasciculations
Diarrhea, nausea, vomiting
10 minutes to 18 hours after exposure
Cardiac
Brady, heart block
Signs and SymptomsSigns and Symptoms
Severe exposureCNS
Resp
GI/GU
LOC, seizures, fasciculations
Weakness, paralysis
Apnea
Bowel/bladder incontinence
Previously described vapour and liquid effects
plus …
Seconds to minutes (vapour)
Minutes to hours (liquid)
ManagementManagement
General managementGeneral management Specific antidotesSpecific antidotes
– AtropineAtropine– Pralidoxime Chloride Pralidoxime Chloride – DiazepamDiazepam– Pre -treatmentPre -treatment
AntidotesAntidotes
Atropine
2 mg IV/IM q5- 15 min to effect
Muscarinic action
-smooth muscle
-glandular epithelium
-cardiac muscle
AntidotesAntidotes
Pralidoxime Chloride
1 g IV over 15-30 min q 1 hr to effect
Nicotinic action
-skeletal muscle
Aging: Irreversible binding of nerve agent to AChE
Soman: 2 minutes
VX: 48 hours
AntidotesAntidotes
Diazepam
Seizure prophylaxis and treatment
10 mg IV at onset of severe symptoms regardless of seizure activity
MARK I kitMARK I kit
Atropine 2 mgAtropine 2 mgPralidoxime Cl 600 mgPralidoxime Cl 600 mg Issued to military personnelIssued to military personnel
Initial dosingInitial dosing Mild Sx (i.e. miosis and mild rhinorrhea)Mild Sx (i.e. miosis and mild rhinorrhea)
– 1 MARK I kit or equivalent1 MARK I kit or equivalent
OROR– No Rx and observe for 1 hr if vapour exposure No Rx and observe for 1 hr if vapour exposure
and mild symptoms and mild symptoms
Moderate SxModerate Sx– 1-2 MARK I kits or equivalent1-2 MARK I kits or equivalent
Severe SxSevere Sx– 3 MARK I kits or equivalent3 MARK I kits or equivalent– Diazepam auto-injector or equivalentDiazepam auto-injector or equivalent
Pre-TreatmentPre-TreatmentPyridostigmine
In animal studies shown to be effective, particularly against rapidly aging nerve agents (e.g. Soman)
No human evidence
FDA waiver for use by military during Gulf War but not currently approved for civilian use in Canada or U.S.
30 mg po q8h
? association with Gulf War Syndrome
Mechanism of actionMechanism of action
Additional testsAdditional tests
RBC–AChERBC–AChE– Decreased in nerve agent poisonings Decreased in nerve agent poisonings
(cholinesterase inhibition)(cholinesterase inhibition)– Systemic effects correlate with decrease of Systemic effects correlate with decrease of
20-25% in levels20-25% in levels– Significant variability so treat the patient Significant variability so treat the patient
not the valuenot the value– Useful for documenting exposure and Useful for documenting exposure and
monitoring recoverymonitoring recovery
DispositionDisposition Patients exposed to nerve agent vapour who Patients exposed to nerve agent vapour who
have only miosishave only miosis and/or mild rhinorrhea when and/or mild rhinorrhea when they reach the medical facility dothey reach the medical facility do not need to not need to be admitted. be admitted.
All other patients who have hadAll other patients who have had exposure to exposure to nerve agent should be hospitalized nerve agent should be hospitalized for for observation.observation.
Pulmonary Agents
ChlorineChlorine First used as a First used as a
chemical weapon in chemical weapon in 1915 by Germany at 1915 by Germany at Ypres, BelgiumYpres, Belgium– Released 160 tons of ClReleased 160 tons of Cl22
when wind was when wind was favourable, resulting in favourable, resulting in 5,000 dead and 10,000 5,000 dead and 10,000 woundedwounded
Bruce Bairnsfather (1888-1959)
ChlorineChlorine Largest cause of major toxic release incidents Largest cause of major toxic release incidents
worldwideworldwide Between 1988-1992, 27,788 exposures to Between 1988-1992, 27,788 exposures to
chlorine in US chlorine in US Attractive as chemical weapon because of Attractive as chemical weapon because of
ease of availabilityease of availability
Chlorine Chlorine DescriptionDescription
– At room temperature, yellow-green gas with aAt room temperature, yellow-green gas with a pungent irritating odopungent irritating odouur. r.
– OOnly slightly soluble in water, but on contact withnly slightly soluble in water, but on contact with moisture it forms moisture it forms hypochlorous acidhypochlorous acid (HClO) and (HClO) and hydrochlorichydrochloric acid acid (HCl)(HCl).. HClO readily HClO readily decomposes, formingdecomposes, forming oxygen free radicals.oxygen free radicals.
– Not explosive but reacts or forms explosive Not explosive but reacts or forms explosive compounds with other substances (e.g. NHcompounds with other substances (e.g. NH33, , acetylene)acetylene)
Routes of exposureRoutes of exposure– InhalationInhalation– Skin/Eye contactSkin/Eye contact
PathophysiologyPathophysiology
Cl2 + H2O
2 HCl (hydrochoric acid)+
[O-]
HCl+
HOCl (hypochlorous acid)
Cellular injury via oxidation of
functional groups in cell components
HCl + [O-]
Clinical effectsClinical effects
Chlorine
Eyes
Upper airway
- Irritation, ocular burns
- Nasal,pharynx, tracheal inflammation
- Laryngospasm
May occur minutes to 24 hours after
exposure
Lower airway - Inflammation and loss of pulmonary capillary integrity
Pulmonary edema, hypoxia
Skin- Irritation, frostbite
Pre-hospital managementPre-hospital management General measuresGeneral measures Low risk of secondary contamination from Low risk of secondary contamination from
victims who have been exposed to gas, victims who have been exposed to gas, however liquid soaked skin or clothing may however liquid soaked skin or clothing may cause off-gassingcause off-gassing
No need for decontamination if no skin or eye No need for decontamination if no skin or eye irritationirritation
ED ManagementED Management Decontamination if not done previouslyDecontamination if not done previously Resp:Resp:
– Fluid restriction in patients with Fluid restriction in patients with pulmonary edema/ pulmonary edema/ ARDSARDS
– Beta agonists Beta agonists – If intubation needed perform under direct If intubation needed perform under direct
visualization (avoid blind techniques)visualization (avoid blind techniques)
Burns:Burns:– Treat as thermalTreat as thermal
DispositionDisposition 6 to 24 hours observation6 to 24 hours observation Asymptomatic patients or minor Sx (eyes, Asymptomatic patients or minor Sx (eyes,
cough) may be released with close follow-up cough) may be released with close follow-up and advice to return if respiratory symptoms and advice to return if respiratory symptoms recur recur
Hospitalization if:Hospitalization if:– Symptoms persist after 6 hours.Symptoms persist after 6 hours.– Patient was severely exposed.Patient was severely exposed.– Child was exposed.Child was exposed.– Patient has a history of underlying respiratory or Patient has a history of underlying respiratory or
cardiovascular disease.cardiovascular disease.
PhosgenePhosgene First synthesized in First synthesized in
1812 1812 First used in 1915 by First used in 1915 by
Germany at Ypres, Germany at Ypres, BelgiumBelgium
Attractive as chemical Attractive as chemical weapon because of weapon because of ease of availabilityease of availability
British soldiers at Somme, 1915
PhosgenePhosgeneDescriptionDescription
– At room temperature, colourless, nonflammable At room temperature, colourless, nonflammable gas with a suffocating odour like new mown hay.gas with a suffocating odour like new mown hay.
– Odour threshold is five times Odour threshold is five times higher higher thanthan permissible exposure levelpermissible exposure level
•i.e. Odour provides insufficient warning of toxic levels•Prolonged severe exposure more likely than with Cl2
–At < 8 degrees C, colorless fuming liquidAt < 8 degrees C, colorless fuming liquid–CCombustion product of manyombustion product of many household products household products that contain volatile organochlorinethat contain volatile organochlorine c compounds. ompounds. ((household solvents, paint removershousehold solvents, paint removers))
Routes of exposureRoutes of exposure–InhalationInhalation–Skin/Eye contactSkin/Eye contact
PathophysiologyPathophysiology
Phosgene
Directly reacts with amine, sulfhydryl, and alcohol groups in
cells
Hydrolyzes to HCL
Stimulates LT synthesis
Combines with and depletesglutathione stores
Clinical effectsClinical effects
Phosgene
Eyes
Upper airway
- Irritation, ocular burns
- Nasal,pharynx, tracheal inflammation
- LaryngospasmMay occur minutes to
72 hours after exposure
Lower airway - Inflammation and loss of pulmonary capillary integrity
Pulmonary edema, hypoxia
Precipitated by exertion
Skin- Irritation, frostbite
Pre-hospital managementPre-hospital management General measuresGeneral measures Low risk of secondary contamination from Low risk of secondary contamination from
victims who have been exposed to gas, victims who have been exposed to gas, however liquid soaked skin or clothing may however liquid soaked skin or clothing may cause off-gassingcause off-gassing
No need for decontamination if no skin or eye No need for decontamination if no skin or eye irritationirritation
Keep warm and quietKeep warm and quiet; any activity ; any activity subsequent to exposure may increase subsequent to exposure may increase likelihood of deathlikelihood of death
ED ManagementED Management Decontamination if not done previouslyDecontamination if not done previously RespResp::
– Fluid restriction in patients with Fluid restriction in patients with pulmonary edema/ pulmonary edema/ ARDSARDS
– Beta agonists Beta agonists – High dose inhaled/IV steroids for severe High dose inhaled/IV steroids for severe
inflammation or known severe exposureinflammation or known severe exposure– PEEPPEEP– If intubation needed perform under direct If intubation needed perform under direct
visualization (avoid blind techniques)visualization (avoid blind techniques) Burns:Burns:
– Treat as thermalTreat as thermal
Animal studies have shown some benefit withAnimal studies have shown some benefit with – NN-Acetylcystine-Acetylcystine– LT antagonists (monteleukast, zafirleukast)LT antagonists (monteleukast, zafirleukast)– NSAIDsNSAIDs– AminophyllineAminophylline
DispositionDisposition
All patients should be hospitalized for All patients should be hospitalized for 48 hours for observation48 hours for observation– Respiratory symptoms warrant ICU admissionRespiratory symptoms warrant ICU admission
Survival to 48 hours predicts likely Survival to 48 hours predicts likely recoveryrecovery
Vesicants
IntroductionIntroduction A group of chemical agents that burn and A group of chemical agents that burn and
blister tissue with which they come into blister tissue with which they come into contactcontact
Mustard gases Lewisite
Halogenated oximesSulfur mustard
Phosgene Oxime
Mustard gasesMustard gases A group of A group of sulphur-, sulphur-,
nitrogen-, and nitrogen-, and oxygen-based oxygen-based vesicant vesicant compounds compounds with similar chemical with similar chemical and biological and biological effects effects
First used by First used by Germany at Ypres, Germany at Ypres, Belgium in 1917Belgium in 1917
“Gassed” John Singer Sargent, 1918
Since then has been used extensively in Since then has been used extensively in numerous conflicts, including by Iraq in the numerous conflicts, including by Iraq in the 1980s1980s
Stored at 7 sites in the U.S.Stored at 7 sites in the U.S.
Sulfur MustardSulfur Mustard DescriptionDescription
– Typically a yellow to Typically a yellow to brown oily substance brown oily substance with a slight garlic or with a slight garlic or mustard odor.mustard odor.
– Individual odor threshold Individual odor threshold variabilityvariability
– Because of stable liquid Because of stable liquid form can be used coat form can be used coat (slime) surfaces (slime) surfaces
Routes of exposureRoutes of exposure– InhalationInhalation– Skin/Eye contactSkin/Eye contact– IngestionIngestion
PathophysiologyPathophysiology
Mustard
Alkylating effect leads to cross-linking and degradation of DNA,
protein, other molecules
Thus high turnover celllines most affected
Cholinergic stimulation
Clinical effectsClinical effects Distinguished by relative lack of symptoms Distinguished by relative lack of symptoms
immediately after exposureimmediately after exposure
Variable latent period depending upon Variable latent period depending upon severity, route of exposureseverity, route of exposure
Clinical effectsClinical effectsTissue Severity Clinical Effects Time
Eyes Mild Tearing, itching, burning 4 –12 h
Mod Erythema, lid edema, pain 3 – 6 h
Severe Corneal damage 1 – 2 h
Airways Mild Rhinorrhea, epistaxis hoarseness,cough
6 – 24 h
Severe SOB, productive cough 2 – 6 h
Skin Mild Erythema 2 – 24 h
Severe Vesication 2 – 24 h
Delayed clinical effectsDelayed clinical effects Leukopenia +/- pancytopenia can occur 3-5 Leukopenia +/- pancytopenia can occur 3-5
days post-exposuredays post-exposure
Pre-hospital managementPre-hospital management General measuresGeneral measures Low risk of secondary contamination from Low risk of secondary contamination from
victims who have been exposed to gas, victims who have been exposed to gas, however liquid soaked skin or clothing may however liquid soaked skin or clothing may cause off-gassingcause off-gassing
Decontaminate all casualties!Decontaminate all casualties!
Decontamination within 1 to 2 minutes is the only way to prevent tissue damage
ED ManagementED Management Decontamination if not done previouslyDecontamination if not done previously
– Shower, mild soap, Na hypochlorite solutionShower, mild soap, Na hypochlorite solution
RespResp::– Beta agonists prn Beta agonists prn – If intubation needed perform under direct If intubation needed perform under direct
visualization (avoid blind techniques)visualization (avoid blind techniques) Skin:Skin:
– BlistersBlisters• Drain large, tense blistersDrain large, tense blisters• Blister fluid is not vesicantBlister fluid is not vesicant
– EythemaEythema• Topical analgesiaTopical analgesia
Additional testsAdditional tests UUrine thiodiglycolrine thiodiglycol
DispositionDisposition Observation for 12 hoursObservation for 12 hours If asymptomatic or mild Sx can discharge with If asymptomatic or mild Sx can discharge with
close follow-upclose follow-up
LewisiteLewisite An arsenical vesicant, first synthesized in An arsenical vesicant, first synthesized in
19181918 No confirmed use in warfare, although No confirmed use in warfare, although
stockpiled by several nations stockpiled by several nations
LewisiteLewisite DescriptionDescription
– Pure Lewisite is an Pure Lewisite is an oily, colourless liquid, oily, colourless liquid, while impure while impure Lewisite is amber to Lewisite is amber to black with odour of black with odour of geraniums. geraniums.
Routes of exposureRoutes of exposure– InhalationInhalation– Skin/Eye contactSkin/Eye contact– IngestionIngestion
PathophysiologyPathophysiology
Lewisite
Exact mechanism of cell damage not known. Inhibits enzymes with
thiol groups (e.g. alcohol dehydrogenase)
Clinical effectsClinical effects Absorbed 10 times faster than mustardsAbsorbed 10 times faster than mustards Immediate clinical effectsImmediate clinical effects More toxic than mustardMore toxic than mustard
– 14 ug of Lewisite can cause vesication14 ug of Lewisite can cause vesication
Clinical effectsClinical effects
LewisiteEyes
- Irritation, severe ocular burns
Skin
-Immediate pain
-Erythema within 30 min
-Vesication within a few hours
GI
-Severe abdo pain, n, hematochezia if ingested
- Hepatic necrosis
Clinical effectsClinical effects
Lewisite
Cardiovascular
Upper airway
- Nasal,pharyngeal, tracheal inflammation
- Laryngospasm
Lower airway
- Inflammation and loss of pulmonary capillary integrity
Pulmonary edema, hypoxia
- Lewisite shock
Pre-hospital managementPre-hospital management General measuresGeneral measures Low risk of secondary contamination from Low risk of secondary contamination from
victims who have been exposed to gas, victims who have been exposed to gas, however liquid soaked skin or clothing may however liquid soaked skin or clothing may cause off-gassingcause off-gassing
Decontaminate all casualtiesDecontaminate all casualties
ED ManagementED Management Decontamination if not done previouslyDecontamination if not done previously
– Shower, mild soap, Na hypochlorite solutionShower, mild soap, Na hypochlorite solution
RespResp::– Beta agonists prn Beta agonists prn – If intubation needed perform under direct If intubation needed perform under direct
visualization (avoid blind techniques)visualization (avoid blind techniques) Skin:Skin:
– BlistersBlisters• Drain large, tense blistersDrain large, tense blisters• Blister fluid is not vesicantBlister fluid is not vesicant
– EythemaEythema• Topical analgesiaTopical analgesia
AntidotesAntidotes
British Anti-Lewisite (BAL)
3-5 mg/kg IM q4h x 4 doses
If severe exposure additional doses 2 mg/kg qd x 3-4 d
No effect on the local lesions of the skin, eyes
Binds to arsenic moiety of L and prevents/reverses binding to enzymes
Severe toxicity thus use only if shock or severe pulmonary injury
Alkalization of the urine stabilizes the Alkalization of the urine stabilizes the Dimercaprol-metalDimercaprol-metal complex and has been complex and has been proposed to protect the kidneys duringproposed to protect the kidneys during chelation therapy. chelation therapy.
If acute renal insufficiency develops,If acute renal insufficiency develops, hemodialysis should be considered to remove hemodialysis should be considered to remove the Dimercaprol-arsenicthe Dimercaprol-arsenic complex.complex.
Additional testsAdditional tests Urinary arsenic excretionUrinary arsenic excretion
DispositionDisposition Observation for 18-24 hoursObservation for 18-24 hours If asymptomatic or mild Sx can discharge with If asymptomatic or mild Sx can discharge with
close follow-upclose follow-up
Riot control agents
Riot control agentsRiot control agents IrritantsIrritants Hallucinogens (e.g. BZ)Hallucinogens (e.g. BZ) Vomiting agents (e.g. Adamsite)Vomiting agents (e.g. Adamsite)
IrritantsIrritants CNCN (Chloroacetophenone,Mace)(Chloroacetophenone,Mace)
– First RCAFirst RCA
CSCS (orthochlorobenzalomalonitrile) (orthochlorobenzalomalonitrile)
– More effective and less toxic than More effective and less toxic than CNCN
OCOC (oloresin capiscum, pepper spray) (oloresin capiscum, pepper spray)
– Currently used by most law Currently used by most law enforcement agenciesenforcement agencies
DescriptionDescription– All are solids and All are solids and
require dispersion require dispersion device to aerosolize device to aerosolize particles particles
Routes of exposureRoutes of exposure– InhalationInhalation– Skin/Eye contactSkin/Eye contact– IngestionIngestion
Clinical effectsClinical effects Prolonged conjunctivitis, corneal opacities Prolonged conjunctivitis, corneal opacities
and iritis associated with CNand iritis associated with CN CS exposure under high humidity and CS exposure under high humidity and
temperature can lead to skin vesicationtemperature can lead to skin vesication Reports of permanent eye damage due to Reports of permanent eye damage due to
blast force from dispenserblast force from dispenser
Reports of death in literatureReports of death in literature– Associated with CNAssociated with CN
• Agent used in excess, and exposed refused to exit Agent used in excess, and exposed refused to exit confined spaceconfined space
– 1977 case report of 11 year old boy, 1977 case report of 11 year old boy, • Exposed to OC, initially asymptomatic for four hours, Exposed to OC, initially asymptomatic for four hours,
then upper airway obstruction and respiratory arrestthen upper airway obstruction and respiratory arrest• 1994 review by International Association of Police Chiefs 1994 review by International Association of Police Chiefs
concluded that OC was not a factor in any reviewed concluded that OC was not a factor in any reviewed deathsdeaths
– 18 of 22 associated with positional asphyxia exacerbated 18 of 22 associated with positional asphyxia exacerbated by drugs or underlying diseaseby drugs or underlying disease
Clinical effectsClinical effects
Irritants
Eyes-Lacrimation, blepharospasm, injection
Skin
-Pain, burning, erythema
ENT
-Sneezing, salivation
Resp
-Cough, broncorrhea, subjective sensation of breathing difficulty
ManagementManagement DecontaminationDecontamination
– Wash exposed skin with mild soap, water +/- 6% Wash exposed skin with mild soap, water +/- 6% Na bicarbonate solutionNa bicarbonate solution
– Na hypochlorite solution can exacerbate skin Na hypochlorite solution can exacerbate skin lesionslesions
– Saline irrigation of exposed eyesSaline irrigation of exposed eyes Supportive managementSupportive management
– Effects generally self-limitingEffects generally self-limiting Most patients can be discharged, further Most patients can be discharged, further
inpatient monitoring and care if respiratory or inpatient monitoring and care if respiratory or severe symptomssevere symptoms
For the prize …For the prize …
“For a charm of powerful trouble,For a charm of powerful trouble,
Like a hellLike a hell broth boil and bubblebroth boil and bubble… …
Double, double, toil and trouble;Double, double, toil and trouble;
Fire burn and cauldron bubbleFire burn and cauldron bubble””
Macbeth, Act IV, Scene IMacbeth, Act IV, Scene I
William Shakespeare, 1623William Shakespeare, 1623
Useful ReferencesUseful References Brennan RJ, Waeckerle JF et al. Chemical warfare agents: emergency medical and emergency
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