Toxic Chemical Threats

Transcription

1 Toxic Chemical Threats John Devlin, MD, FACEP GA Poison Center / Emory University / Centers for Disease Control and Prevention

2 Objectives To give you tools to help recognize what chemical agent is present To give an overview of chemical agents and their management To identify considerations at each level of care in the event of a chemical incident You don t have to be a genius to be a toxicologist, you just have to know common sense decontamination and good supportive care

3 Why Chemical Terrorism? Agents are available & relatively easy to manufacture Large amount not needed in enclosed space Chemical incidents may be difficult to recognize Easily spread over large areas Psychological impact Can overwhelm existing resources

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5 Are our EMS and hospitals ready?

6 Are we ready? Index pt ingests 110 mg OP insecticide 45 y/o tech resp distress (intubated, admitted x 9 days) 32 y/o RN treated with atropine / pralidoxime 56 y/o RN treated with atropine, admitted x 1 day MMWR, January 5, 2001

7 Limitations of Chemical Agents Effective dissemination difficult Delayed effects can detract from impact Potentially hazardous to the terrorist Development and use require skill More expensive than biologic agents

8 Chemical vs. biological agents Chemical More rapid onset More rapid resolution ID requires recognizing syndrome or detection of compound Morbidity / mortality dependent on agent and concentration Biological Incubation period Sporadic pt presentation ID requires recognizing syndrome or detecting agent Morbidity / mortality dependent on agent and concentration

9 Potential Terrorist Targets Enclosed spaces Large crowds (high profile events) Critical facilities and infrastructure Accessible facilities with significant hazard / damage potential (materials in transit) Facilities of interest to terrorists cause

10 The Myths It can t happen to us Chemical agents are so deadly the victims will all die anyway There is nothing we can do keting.com/social-mediamyths/

11 Steps needed in event of a release 1 First responder protection Bystander protection Substance ID via placarding via shipping papers via physico-chemical properties ideally confirmed by a second method

12 HAZMAT During Transit

13 Using the 2008 ERG

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16 Medical Management of Hazmat Victims Decon Remove the pt from the poison Remove the poison from the pt Life Threats Stop massive bleeding Open airway, support breathing HAZMAT Assessment Identify toxidromes Administer antidotes

17 Toxidrome Toxic + Syndrome= Toxidrome A way to categorize chemical agents that share similar clinical effects

18 Toxidromes Nerve Agents Blood Agents Blister Agents Choking Agents

19 Military Nerve Agents Organophosphate Pesticides Carbamate Pesticides

20 Nerve Agent Toxidrome Cholinergic Agents Nerve Agents Tabun (GA) Sarin (GB) Soman (GD) Vx ic-drugs.html Symptoms SLUDGEM DUMBBELLS

21 Nerve agents Recognition muscarinic nicotinic Defecation -Fasciculations Urination -Weakness -Seizures Miosis (small pupils) Brocho-spasm/rhea Emesis Lacrimation Salivation Resp Weakness

22 Nerve Agent Comparison Agent LD 50 (mg) Aging t 1/2 Volatility Tabun hrs Low Sarin hrs Soman s 10 min VX days High Moderate Non

23 Cholinergic Toxidrome Organ systems affected: respiratory, neurological, cardiovascular Decontamination: full decon Antidotes: Mark I kit: Atropine and Pralidoxime Management: ABC, prompt decon and antidote therapy, supportive care

24 Nerve Agents Treatment Atropine until secretions are gone 2-PAM (pralidoxime) x3 auto-injectors or 30 mg/kg IV Valium for seizures

25 Nerve Agent Example

26 Nerve Agent Example 1994 Matsumoto 7 killed 500 injured 1995 Tokyo Subway 12 killed 5500 sought medical attention

27 Tokyo Sarin Gas Attack St Luke s ED received 640 patients within a few hours Medical staff complained about eye and throat pain, nausea, miosis ED provisions for privacy to remove clothing or to provide showers was inadequate Okumura et al: Report of 640 victims of the Tokyo subway sarin attack. Ann Emerg Med Aug 1996

28 The arriving patients 640 patients 64 arrived by ambulance 35 arrived by fire department vehicles 541 arrived with the assistance of nonmedical motorists 106 were admitted for severe symptoms 4 pregnant

29 NA antidotes Give atropine until secretions are dry Dosages for pralidoxime (mention european antidotes)

30 Pulmonary agents Military Pulmonary Agents Industrial Chemicals

31 Toxic Gases (Choking Agents)

32 Choking Agent Toxidrome Irritant Gases Effects dependent on water solubility Local effects Eyes Mouth Throat Lungs Chlorine, Ammonia, Hydrogen Chloride, Phosgene, Chloramine

33 Water solubility effect: Chlorine vs. Phosgene Chlorine Phosgene Irritates eyes and MM Non-irritating Pungent odor Immediate symptoms Full recovery Odor threshold above toxic threshold Delayed symptoms Prolonged sequelae RNpedia.com

34 Particle size influences bioavailability

35 Toxic Gases / Choking Agents Therapy Oxygen as needed Albuterol nebs, steroids controversial Treat local effects Antibiotics not necessary Beware of delayed onset of pulmonary edema in pts with previous bronchospasm Up to 6-8 hours

36 Graniteville, SC

37 Admission

38 6 Hours

39 15 Hours

40 30 Hours

41 Toxic Gases / Choking Agents Organ systems affected: Respiratory Decontamination: not required unless concentrated liquid Antidote: none Management: oxygen, supportive care Effects may be delayed up to 6-8 hours

42 Nebulized Bicarbonate Chlorine gas exposures may respond to bicarb nebs Dilute ampule of sodium bicarbonate with equal part sterile water Nebulize 3mL

43 Blood agents Simple Asphyxiants CO 2, inert gases Systemic Asphyxiants Cyanide / H 2 S Carbon Monoxide

44 Asphyxiant Toxidrome Asphyxiants Simple volume displacement Carbon Dioxide Systemic (Blood Agents) Carbon Monoxide, Cyanide, Hydrogen Sulfide, Azides Symptoms Fast Breathing, Fast Heart Rate, Confusion, Acidemia, Hypoxia

45 Simple Asphyxiants Organ systems affected: Respiratory Decontamination: none Antidotes: none Management: remove them from environment, oxygen

46 Simple Asphxiants

47 Preventing Knockout Scenarios 5 tactics that can be used to prevent secondary contamination. Use PPE, including respirators and chemical-resistant clothing. Initial assessment / decontamination should be done outdoors or in a room with separate ventilation to the outside. Isolate the patient from others (patients and staff) Remove the patient's clothing. Decontaminate the patient.

48 Blood Agents Organ systems affected: neurological, cardiovascular Decontamination: charcoal for ingestion (cyanide salts) Antidotes: Cyanide (Lilykit) treatment kit or hydroxocobalamin (Cyanokit), Hyperbaric oxygen for CO Management: oxygen, antidote therapy and supportive care

49 Blood Agent Example Systemic asphyxiants: Pink skin because body cannot utilize oxygen

50 Blood Agent Example Jonestown, 1978 Kool-Aid mixed with cyanide and sedatives

51 Treatment of Cyanide Toxicity Hydroxocobalamin Sodium Thiosulfate

52 Carbon Monoxide Binds to hemoglobin, displaces oxygen CANNOT carry oxygen in the red blood cells Treatment: 100% oxygen, +/- hyperbaric oxygen chamber treatemnts

53 Structure Fires Background Burning silk / wool / plastics liberate cyanide Co-exposure to CO and CN not uncommon in structure fires Clinical Cherry red skin can be CO or CN Lactate > 10 treat for cyanide Do NOT give nitrate portion of Lily Kit No change with hydroxocobalamin

54 Blister agents Military Blister Agents Mustard Gas, Lewisite

55 Vesicant Toxidrome Vesicants Respiratory difficulties Redness and blistering to the skin Lewisite- immediate effects Mustards- delayed Nitrogen Sulfur» Also causes bone marrow suppression

56 Vesicants Agents

57 Vesicants Toxidrome Organ systems affected: respiratory, dermal, cardiovascular Decontamination: full decon Antidotes: none Management: Decontamination and supportive care

58 Level C Level A Level B

59 Decontamination

60 Decontamination Ambulatory decontamination Ratio 1:4, responders to victims Stretcher decontamination Ratio 2:1, responders to victims Watch for hypothermia, privacy, valuables

61 Miscellaneous Industrial Agents Corrosives Dermal burn injuries Mucosal burns Hydrocarbons Flammability CNS depression, confusion Heart dysrhythmias Hydrazines Seizures

62 What have we learned?

63 Recommendations for Japan Emergent decontamination areas Available chemical resistant suits and masks Ventilation in ED and main treatment areas Disaster planning must address mass casualties, staff call up, medical charting Information network Okumura et al: The Tokyo subway sarin attack Acad Emerg Med 1998

64 Steps needed in event of a release Pre-hospital Scene security Triage and tracking Victim decon before transport Evacuation and transport

65 Steps needed in event of a release Emergency Department Treatment of victims decontamination before entry into the ED treatment, geared to severity of injuries and scope of event Locate health care resources needed, redeploy if necessary

66 Considerations for Hospital Preparedness Command and Control (ICS) Security PPE Primary Triage Patient Tracking Patient Decontamination Indoor or outdoor Privacy Environmental exposure

67 Steps needed in event of a release Hazard abatement containment risk mitigation Health Department Scene investigation Clean up

68 Preparedness efforts Most hospitals have been poorly prepared for chemical releases Only 3 of 42 metro Atlanta hospitals surveyed had on-site level B decon capabilities 2 weeks before the Olympics, not much improvement 5 yr later Prevalent attitude was: It won t happen here

69 Further Considerations Specific antidotes/vaccinations/antibiotics Deployment of pharmaceutical stockpile Specific supplies Ventilators, critical care supplies Information resources

70 Summary Chemical event response requires cooperative interaction Local education on HAZMAT response, decontamination and containment is imperative Work with hospitals and clinicians to plan prior to an event Medical treatment will be based empirically on symptoms, labs will not be readily available for initial victims Primarily supportive care Antidotes as appropriate

71 Any Questions?