A new risk in the field: « Chemical weapons » Dr Frédéric Baud, MD Toxicologist OCP Jean-baptiste Ronat, Laboratory advisor OCP Benoit Leduc, Security Advisor OCP MSF Surgical day: 30/11/2013
Summary 1. What are chemical weapons? 2. A Contingency plan on “chemical weapons threat in the syrian context�: Why? Where? For what? To whom? 3. Management: from protection to treatment 4. Conclusion
1. What are chemical weapons? 2. A Contingency plan on “chemical weapons threat in the syrian context�: 3. Management: from protection to treatment 4. Conclusion
-Classes of chemical weapons – A limited number of credible agents Toxicity Agents Not CWA
Riot control agents (tear gas): CN (Mace), CS
CWA
Blistering (vesicant) agents: sulfur mustard and lewisite
CWA
Nerve agents (organophosphates): GA (tabun), GB (sarin), GD (soman), VX
CWA
Phosgene, chlorine, choking agents
CWA
Cyanide, hydrocyanic acid, cyanogen chloride
CWA
Arsine (AsH3): intravascular hemolysis
CWA
BZ (QNB)
CWA
Opioids
CWA DISPERSAL Threats with CWA are limited in area and over time: • Limited in area:
0.7Km/
Chemical downwind hazards (erg 2004) a small release is 45gal or 200 liters of chemical and a large release is anything bigger
A rocket or a shell (122-155 mm): 3 – 5 liters of Sarin
• Limited in time:
– whatever the CW, the number of casualties will increase within the first 24 hours after the attack and then decrease. – Casualties depend on how widely the agent is dispersed and on the persistence of the agent:
• liquids can be dispersed in suitably modified conventional weapons, including bombs and missiles. • spray from aircraft less efficient = difficulties generating fine vapor.
CWA (Persistence of CWA (Persistence of toxicity on toxicity on surface< 12 Hrs) surface< 48 Hrs) Riot Agents Blood agent (Cyanide)
Blister agents Nerve agents Vx can remain for several weeks
Psychotropic agents Choking agents
Blood agent (Arsine)
1. What are chemical weapons? 2. A Contingency plan on â&#x20AC;&#x153;chemical weapons threat in the syrian contextâ&#x20AC;?: why? Where? For what? to whom? 3. Management: from protection to treatment 4. Conclusion
Why? For what? To whom? End of 2012: suspicion of use of Chemicals Weapons Agent’s in Syria Field request: what to do? Is it real risk? E desk facing unknown security constraint MSF staff are potentially at risk of being exposed to such threat. MSF members need to be informed of the risks, evacuation plans and protection measures that exist. • Since July 2013: availability of contingency plan aiming at • • • • •
– – – – –
support field team to rationalized risk and make the proper decisions provide support to protect staff evacuate safely. Initial management of staff contaminated in outreach condition Operational centers decision to treat influx of chemical victims.
Where? • Restricted to MSF programs in the Syrian context • MSF would not attempt to enter into a contaminated area • MSF doesn’t intend to intervene or rescue population in a contaminated area • MSF would NOT be involved in gathering evidence • The location of and time for chemical attacks are unpredictable! • We then: – Selected knowledge required by MSF team on the field – Prepare different credible scenarios – Identify and select specific Personal Protective Equipment (PPE) and treatments
1. What are chemical weapons? 2. A Contingency plan on â&#x20AC;&#x153;chemical weapons threat in the syrian contextâ&#x20AC;?: why? Where? For what? to whom? 3. Management: from protection to treatment 4. Conclusion
How to manage a crisis? ⇒ Define the scenario: 4 majors only! ⇒Rumors only? ⇒ Signs and symptoms? If signs and symptoms, try to define: - Targeted organs - Time-course of signs Needs for protecting care givers Needs for supportive treatment Needs for antidotes
-Organ toxicity – Time-course Agents
Targeted Organs
Time-course
Riot control agents (tear gas): CN (Mace), CS
Eyes - Nose
Rarely life-threatening
Blistering (vesicant) agents: sulfur mustard and lewisite
Eye – Nose-Skin
Delayed effects; Long-lasting incapacitation related to burns healing
Nerve agents (organophosphates): GA (tabun), GB (sarin), GD (soman), VX
Eyes (irritation and myosis) – Nose – Skin Respiration – Gastro-intestinal – Neurological - Cardiovascular
Immediately life-threatening
Phosgene, chlorine: choking agents
Eyes – Nose – Skin - Respiration –
Delayed effects, frequently lifethreatening
Cyanide, hydrocyanic acid, cyanogen chloride
Neurological-cardiovascular-respiration Neurological - Respiration
Immediately life-threatening
Arsine: intravascular hemolysis
Gastro-intestinal – Jaudnice - Red/dark urine -
Delayed effects, possibly life-threatening
BZ (QNB) LSD
Abnormal behaviour - Mydriasis
Rarely life-threatening
Opioids
Sedation – Myosis – Bradypnea/apnea
Immediately life-threatening
Nerve agents 1. Delay in onset of injuries = almost no delay 2. Organs targeted by the agents = Eye, respiration, muscles, consciousness, gastro-intestinal 3. Delays in recovery = hours to days Number of immediate deaths = - Numerous immediate deaths at the scene or - Casualties immediately collapsing
Burns induced by sulfur mustard Closed painful irritated eyes Burns of the face, the neck CUTANEOUS BLISTERS Bilateral blisters in the axillary pits
Burns of the backside of the hands and wrists
Sulfur mustard Cutaneous Burns of the Backside Of the hands
Burns around the ankles
Choking Gas Chlorine - Phosgene
Persistant, painful red eyes
Dysphonia, inspiratory dyspnea, Stridor +++ means obstructive Alpha & Bravolaryngitis 21 May 2013
Whatâ&#x20AC;&#x2122;s about the toxidrome induced by Choking gases
Alpha & Bravo 21 May 2013
ANTIDOTES
Conclusion •Before use, CWA are a fear, a threat •During use, CWA results in an invisible Hurricane •CWA aims at causing the largest number of casualties and/or fatalities in one attack •During use, CWA are a nightmare for medical doctors not only to care victims but also protect care givers.
Conclusion Therefore, â&#x20AC;˘Before use of CWA, awareness of use and knowledge of hazards are mandatory â&#x20AC;˘Preparedness in the lone way to decrease the devastating effects of CWA Yes, we can!
Questions? The contingency plan was done with the support of the following specialists: – – – – – – – –
Mansoor Ali, OCP Dr Frédéric Baud, MD Toxicologist OCP Steve Ryan, Security Advisor OCBA Benoit Leduc, Security Advisor OCP Jean-baptiste Ronat, Laboratory advisor OCP Sarah Imani, Web designer Stephen Donnelly, ICRC NRBC response team Emergency desks, Medical department