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DECEMBER 2003
Volume 2, Issue 10
AS PRESENTED IN THE
DEPARTMENT OF
ANESTHESIOLOGY,
FACULTY OF MEDICINE
UNIVERSITY OF MONTREAL
Biochemical Terrorism:
Committee for Continuing
What the Anesthesiologist Should Know
Medical Education
Department of Anesthesiology
University of Montreal
MAJOR DANIEL AUDY, MD, FRCPS, B.SC. BIOCHEMISTRY, CD Pierre Drolet, MDChairman and Editor Although the chances of a biological or chemical attack occurring in Canada
are slim, the consequences of such an attack could be devastating. As a result, it
Jean-François Hardy, MDChairman of the is very important for anesthesiologists to have a basic understanding of the vari-
ous biological and chemical agents involved, and the appropriate treatments.
For each type of agent, there are fundamental rules that apply. Biological agents
include anthrax, plague, botulism, tularemia, and smallpox, while chemical
agents are neurotoxins, cyanogens, pulmonary agents, and vesicants. In the
event of a massive attack, demands for treatment would exceed available
resources. Physicians in charge would have to carefully triage victims to opti-
mize treatment capacity and thereby increase patients’ chances of survival. In
addition to the trauma caused by the agents, there is also the necessity of pro-
viding adequate psychological support because many of the victims will have
symptoms of response similar to combat stress. This issue of Anesthesiology
Rounds reviews the background to biochemical warfare, the potential agents
involved, procedures of decontamination, and the processes of triage.
INTRODUCTION
University of Montreal
Department of Anesthesiology
Bioterrorism is defined as the use of microorganisms with the deliberate intention Faculty of Medicine
of infecting a predetermined population in order to achieve certain goals or objec- tives. Chemical terrorism is defined as the use of chemicals with the deliberate inten- tion of causing illness in a predetermined population in order to achieve certain Since these microorganisms and chemicals are easy to obtain, cheap to produce, and very hard to detect, biological and chemical terrorism could become weapons of choice in the future. Although the chances of this type of attack occurring in Canada are slim, if one did, the consequences could be devastating. According to Center for Faculty of Medicine
Disease Control (CDC) estimates, under certain conditions, an anthrax attack on a pop- Department of Anesthesiology
ulation of 100,000 Canadians would result in 50,000 anthrax cases or one out of every two persons, 32,875 deaths, 332,500 days of hospitalization, and a cost of $6.5 billion.
The editorial content of AnesthesiologyRounds is determined solely by the In the face of such possibilities, anesthesiologists should know how to effectively treat the victims of this type of attack. This knowledge extends to several areas including the University of Montreal Faculty of Medicine decontamination and victim triage, the protection of medical personnel, recognition of the symptoms, and the proper medical treatment for each agent that might be used.
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BACKGROUND
hospital. Personnel working in the decontamina- During World War I, it was discovered that the tion zone must be prepared to administer anti- use of certain chemicals (cyanogens, phosgenes, dotes, if needed (eg, atropine and 2-PAM).
and mustard gas) increased the number of injured and was, therefore, a formidable weapon. During World War II, the German army developed neuro- These situations produce a number of patients toxins. In the 1970s, the Vietnam government whose needs exceed available resources. This makes it used them against Cambodia. In the 1980s, the essential to do an efficient triage in order to optimize Russians deployed them against Afghan rebels.
the care given, as well as, the number of survivors. More recently, Iraq engaged in chemical warfare Patients are divided into 5 groups that represent against the Kurds. In the 1990s, a sarin gas attack occurred in the Tokyo subway. Lastly, in 2001 there • P1 (immediate treatment): These patients are were anthrax attacks in the United States. Unfortu- nonambulatory and need treatment as soon as nately, one can expect these types of attacks to possible. Their lives are in danger.
• P2 (delayed treatment): These patients require medical treatment, but it can wait. Their lives are not DECONTAMINATION AND PROTECTIVE GEAR
in any immediate danger, but that could happen Decontamination is essential. Its purpose is to stop absorption by the victim of an attack, as well • P3 (minimal treatment): These patients are as to prevent the contamination of medical equip- ambulatory and require a basic examination. They ment and personnel, thereby keeping the number are conscious, breathing spontaneously, and have of victims from climbing. Failure to decontaminate victims can only aggravate the situation and add to • Dead: Patient dead on or after arrival.
losses of equipment and personnel. Therefore, every • Psychogenic: These ambulatory patients show patient suspected to have come into contact with a no signs of a physical attack, yet, display various chemical substance or biological agent must be symptoms. For example, in the 1995 incident in decontaminated before receiving actual medical Tokyo, the ratio of psychogenic to poisoned victims In the case of biological agents, decontamina- EXAMPLE OF FAST TRIAGE
tion is minimal and involves undressing the patient and applying the infection control proce- • Is the patient ambulatory? If so, the patient is dures in effect at the healthcare centre. With chemical agents, however, decontamination is • If not, is the patient breathing spontaneously? essential. Rule No. 1 is to protect the personnel If not, are the airways blocked? If not blocked, the doing the decontamination. This protection involves wearing a gas mask that protects against • If breathing spontaneously, what is the respi- pesticides, impervious or Tyvek protective cover- ratory rate? If <10 or >30 breaths/minute, the alls, butyl gloves, and rubber boots. The second patient is a P1. If the respiratory rate is between rule is to undress the patient and put all their clothing into a trash bag, and then wash the vic- • Next, check circulation by measuring the tim with soap and water in a bath or shower. After pulse and capillary return. Is the pulse <50 or >120 that, the patient can be moved to a treatment beats/minute and/or capillary refill >2 seconds? If so, the patient is a P1; if not, a P2.
It is also important to remember that the decon- BIOLOGICAL AGENTS
tamination zone should be located as far as possible from ventilation ducts. Moreover, it is absolutely The ground rules: recognize, inform, decontam- essential to keep any person or object that has not inate, and treat. It is vital to recognize the possibility been decontaminated from entering the rest of the of a biological attack if there is a sudden increase of illness in a previously healthy population. Both against the patient’s various bodily fluids until at humans and animals are stricken, and a higher least 3 days of treatment have elapsed. The incuba- incidence of the illness is found in a particular geo- tion period is 1 to 3 days. The diagnostic tests graphic area or timeframe. This can take the form are examination of saliva, blood, CSF, and bubo of a sudden increase in a nonspecific syndrome aspiration to search for Gram+ coccobacilli .
such as pneumonia, influenza episodes, fever, The signs and symptoms are a sudden onset of coagulation disorders, unexplained skin or mucosal fever, chills, headache, myalgia, and prostration.
rash or irritation, and neuromuscular disorders.
The pulmonary form produces coughing, hemopty- If the signs prove positive, the next step is to sis, chest pain, and pneumonia with lung cavity. In inform by notifying management at your establish- the bubonic form, there are cervical, axillary, and ment as well as public health officials. It is impor- inguinal adenopathies. This is followed by sep- tant to run diagnostic tests and activate the ticemia, myocarditis, hypotension, convulsions, emergency measures plan. Remember that deconta- disseminated intravascular coagulation, and necro- mination is usually not necessary for biological agents. It is necessary, however, to undress the For treatment, in addition to support, the rec- patient and place their effects in a trash bag. Your ommendation is streptomycine 15 mg/kg/day IV establishment’s infection control procedures divided into 2 doses or gentamicine 1-1.75 mg/kg IV q8h, or tetracycline 500 mg IV qid, all for 10 days. Preventive treatment is recommended for Anthrax
asymptomatic contacts: doxycycline 100 mg po bid, The causal agent is Bacillus anthracis. Transmis- or ciprofloxacine 500 mg po bid, or tetracycline 250 sion is by inhalation, ingestion, or through the mg po qid, all for 7 days. No vaccine is available.
skin. It is not communicable from person to per- Botulism
son. Infection control procedures must be applied.
The incubation period averages 2 to 6 days, but The causal agent is the botulism toxin and trans- may be as long as 8 weeks. The diagnostic tests are mission is by inhalation and ingestion. The illness Gram’s stain, blood agar culture which reveals the is not communicable from person to person. The presence of Gram+ bacilli, and ELISA.
usual infection-control procedures must be applied.
The signs and symptoms mimic an influenza The incubation period averages 12 to 72 hours, yet episode with fever, pneumonia, and sudden dysp- can range from 2 hours to 8 days. The diagnostic nea. A lung X-ray reveals a mediastinum enlarged tests are a bioassay on mice (5-7 days) and an ELISA by adenopathies. On the skin, pruriginous papules to check for the presence of botulism toxin. appear first, followed by ulcers that are painless and The signs and symptoms are: an absence of fever; the pupils are dilated or nonreactive, The treatment combines ventilatory support diplopia, and palpebral ptosis; paralysis of the cra- with antibiotherapy (ciprofloxacine 400 mg IV q8- nial nerves with dysarthria and dysphonia. Also 12h or doxycycline 200 mg IV initially, then 100 observed are descending flaccid paralysis without mg IV q8-12h). The recommended preventive treat- sensory dysfunction, and paralysis of the diaphragm ment is ciprofloxacine 500 mg po bid or doxycline with respiratory arrest. Mental state remains intact. 100 mg po bid. Amoxicilline is preferable for preg- Treatment includes ventilatory support, par- enteral hyperalimentation, and the use of botulinic antitoxin that improves the prognosis if adminis- Plague
tered early. No preventive treatment is available.
The causal agent is Yersinia pestis and transmis- Tularemia
sion is by inhalation. Only the pulmonary form of the disease is communicable from person to per- The causal agent, Francisella tularensis, comes son. In addition to the usual precautions to prevent from the carcasses of dead animals. Transmission is infection, protective measures must be taken by inhalation. It is not communicable from person to person. The usual infection-control proce- vomiting and mentally disabling chemicals.
dures should be applied. The incubation period This discussion will focus on the lethal agents. is 2 to 5 days, but occasionally reaches 21 days.
The presence of these agents should be sus- The diagnostic tests are the presence of Gram- pected with the sudden occurrence of unusual negative bacilli on blood agar-culture and a illnesses or the increased density of a syndrome in a geographic area and timeframe. In brief, The signs and symptoms are fever, chills, any sudden rise in the following nonspecific headaches, chest pain of the pleuritic and symptoms of hypersecretion (lacrimation), increased expectoration and diarrhea, irritated adenopathies. Widespread adenopathies and eyes and airways, and the presence of skin hepatosplenomegaly are also observed. Various lesions (erythema, vesicles, pruritis) should be diffuse skin rashes may occur as well. Tularemia If an attack is suspected, it is important to notify officials, the poison centre, public health mycine 15 mg/kg IM bid or gentamicine 3-5 officials, and management at your hospital.
mg/kg/day IV, or ciprofloxacine 400 mg IV bid, Apply your establishment’s emergency measures all for 14 days. The recommended preventive plan. With exposure to chemical agents, decont- treatment is ciprofloxacine 500 mg po bid, or amination is extremely important and must be doxycycline 100 mg po bid, or tetracycline 250 the first stage of treatment. This means immedi- mg po qid, all for 14 days. No vaccine is ately establishing a decontamination zone, undressing and decontaminating patients with soap and water, throwing all their effects into a Variola or Smallpox
trash bag and sealing it. Remember, treating The causal agent is the variola virus. Trans- patients before decontaminating them in an mission is by inhalation and from person to uncontaminated area will contaminate that area.
person. The usual infection-control procedures Neurotoxic Agents
apply. The patient and their clothing must be washed. Caregivers must wear masks. The incu- Neurotoxic agents are odourless, colourless bation period averages 2 to 17 days. The diag- and tasteless; hence, they can be present with- nosis is confirmed by electronic microscope out being detectable. These agents bind to examination of pustular content. Smallpox is acetylcholinesterase, increasing stimulation at highly contagious; 33% of exposed individuals nerve, nerve and muscle fibre, and nerve and effector cell. They include derivatives of phos- myalgia, abdominal pain, and delirium. The skin phoric acid. The treatment resembles that for exhibits pruritis and a rash that is initially macu- organophosphates (insecticides) intoxication.
lopapular, then becomes vesicular. These lesions Absorption is by inhalation and through the first affect the extremities (head, arms, legs).
skin. The onset of their action is swift: a few The only treatment is support. Vaccinating seconds for vapors and a few minutes to a few all potential contacts and caregivers is vital.
CHEMICAL AGENTS
sore eyes, problems seeing, runny nose, exces- These agents fall into two categories: lethal, sive salivation, excessive sweating, increased which includes neurotoxins, cyanogens, pul- expectorations, nausea, vomiting, abdominal monary agents and vesicants; and non-lethal, cramps, diarrhea, tenesmus, urinary and fecal which includes tear gas, agents that cause incontinence, asthmatiform crisis, bradycardia, cyanosis, apnea, muscular weakness and trem- sodium nitrite 300 mg IV in 3 minutes and bling. Severe cases also bring hypotension, sodium thiosulfate 12.5 gm IV in 5-10 minutes.
fasciculations, convulsions, stupor, and loss of If, 30 minutes later, there is no response or the The diagnostic tests are plasmatic choline- sodium thiosulfate must be readministered sterase dosage and urine screening. Treatment once at half the initial dose. It is important to begins by undressing and washing the patient remember that nitrite converts Hb into MetHb with soap and water. If the patient’s condition and thiosulfate converts cyanide into thio- is serious, a rapid injection of pralidoxime cyanate. Remember, as well, not to administer methylene blue because it can convert MetHb atropine 2 mg IV is necessary. The main treat- into Hb and thereby antagonize the action of ment is one of support combined with admin- Pulmonary Agents
20-30 minutes which can be repeated twice at intervals of 60-90 minutes (remember that pralidoxine’s T1/2 is 1-1.5 hours), and atropine grass and are only absorbed by inhalation.
2 mg IV q 5-10 minutes until the secretions They are quickly destroyed by water. This class diminish and ventilation improves. If the includes phosgene and chlorine. They cause symptoms are severe, the case may call for pulmonary edema and the symptoms appear in period, 200 mg IV of atropine may be neces- sary. Lorazepam or diazepam IV should be used stages; the first stage is characterized by cough- ing, watery eyes, sore throat, and headache.
This is followed by the latency phase during Cyanogens
which the symptoms disappear. Finally, the late Cyanogens are colourless, but they have an phase occurs 2 to 24 hours later; it is character- almond scent detectable by 60%-80 % of the population. Absorption is by inhalation and mucosal erythema, dyspnea, wheezing, orthop- through the skin. These agents cause cellular nea, increased expectorations, chest pain, asphyxia by blocking the oxydase cytochrome.
pulmonary edema, hypovolemia, and a state of They are fast-acting (within seconds to a few shock. There is no specific test, but the white The signs and symptoms include dizziness, eye irritation, weakness, difficulty breathing, tion. The treatment is one of support. Patients nausea, headaches, and confusion. The venous improve within 48 hours or die. The long-term complications are asthma and emphysema.
branes are pink. At first, there is a rise in Vesicants
heartrate and blood pressure; this is followed Vesicants are liquid oil dispersed in a fine arrest. Loss of consciousness, convulsions, and mist and they smell like garlic, horseradish, or respiratory arrest may also occur. The diagnos- mustard. Typical vesicants are mustard gas and tic tests include blood and urinary thiocyanate, lewisite agents. Absorption is by inhalation and through the skin. Their action begins within 12 to 72 hours, yet, the range extends from 2 patient, providing support therapy, correcting the acidosis and administering the antidote: amylnitrite by inhalation q 90 seconds through the skin with erythema, burn-type pain, pruritis the victim’s mask (4-5 ampules maximum), and vesicles; the eyes with burning, redness and lacrimation; the respiratory system with sore 6. Unknown. Canada Communicable Disease Report: Bioterrorism and public Health. Volume 27-04. February 2001.
throat, productive cough, hoarse voice, dyspnea, 7. Office of Public Health and Environmental Hazards, Depart- pneumonia, and acute edema; and lastly, the diges- ment of Veterans’ Affairs of the United States of America.
Chemical Terrorism General Guidance, Pocket Guide. Washing- tive system with nausea, vomiting, and diarrhea.
There is no specific test. Decontamination consists 8. Office of Public Health and Environmental Hazards, Depart- ment of Veterans’ Affairs of the United States of America.
of undressing and washing the patient with a large Biological Terrorism General Guidance, Pocket Guide. Washing- The treatment is the same as for chemical burns with the addition of support therapy. Note too, Upcoming Scientific Meetings
that for lewisite agents, you can use BAL (British antilewisite), an ointment applied to the skin UCSD Anesthesiology Update 2004
lesions, and dimercaprol 10% by injection IM (3-4 cc) which must be administered as soon as possible, followed by additional injections 4, 8 and 12 hours later. In severe cases, this is followed by regular injections of 2 cc IM dimercaprol for 3 to 4 days.
21-24 January 2004
14th Annual Current Topics in Anesthesiology
CONCLUSION
It is important for anesthesiologists to be famil- iar with the various aspects of medical treatment Fax: 480 301-8323Email: [email protected] for all the agents most likely to be used in a terrorist attack. Adherence to, and the application of, basic principles regarding decontamination, treatment, The 6th International Conference on
Pain & Chemical Dependency
Major Daniel Audy, MD, FRCPC, BSc, CD, is an
anesthesiologist at the Maisonneuve-Rosemont Fax: 1 609-275-5029Email: [email protected] Hospital. He has worked for many years as a medicalspecialist in the Canadian Armed Forces. 13-16 February 2004
4th Annual Mont Tremblant Anesthesia Meeting
References
1. Wiener SL, Barrett J. Trauma Management for Civilian and CONTACT: Mary Kumor, Dept. of Anesthesiology, Military Physicians. Saunders Company. 1986.
2. Office of Public Health and Environmental Hazards, Depart- ment of Veterans’ Affairs of the United States of America.
Rapid Contingency Plans for Responding to Victims of a Chemi- cal Attack, Handling Casualties and Decontamination. October2001.
3 Mintz LTB. 4th Canadian Mechanized Brigade Group. Nuclear, Change of address notices and requests for subscriptions Biological and Chemical Warfare Mini Lesson Guides. July to Anesthesiology Rounds are to be sent by mail to P.O.
Box 310, Station H, Montreal, Quebec H3G 2K8 or by 4. World LCol M. Clinical Manifestations of Unconventional fax to (514) 932-5114 or by e-mail to info@snellmedical.
Weapon Exposure. Royal Army Medical College. England. 1995.
com. Please reference Anesthesiology Rounds in your 5. Kay LCol JL. Practical Casualty Management in a Nuclear, correspondence. Undeliverable copies are to be sent to Biological and Chemical Environment. Royal Army Medical This publication is made possible by an educational grant from 2003 Department of Anesthesia, Faculty of Medicine, University of Montreal, which is solely responsible for the contents. The opinions expressed in this publication do not necessarily reflect those of
the publisher or sponsor, but rather are those of the authoring institution based on the available scientific literature. Publisher: SNELL Medical Communication Inc. in cooperation with the Department
of Anesthesia, Faculty of Medicine, University of Montreal. All rights reserved. The administration of any therapies discussed or referred to in Anesthesiology Rounds should always be consistent with the
recognized prescribing information in Canada. SNELL Medical Communication Inc. is committed to the development of superior Continuing Medical Education.

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