Blister Gas

1
Blister Gas

• Stevan Cordas DO MPH
• Committee of Bioterrorism Texas Department of
  Health

2
History of Blister Gas

• 1822- First discovered.
• 1860- Ability to produce burns and vesicles
  proven.
• 1917 Used by Germans for the first time at
  Ypres, France. Called Yperite by French. Lost by
  Germans.
• Called yellow cross by the allies and later H and
  HD. H stood for Hun. HD produced 85 of chemical
  casualties in WWI.

3
(No Transcript)
4
Sulfur Mustard, 2,2, - Di (Chloro-ethyl)-sulfide
5
Different Vesicants and NATO Designations

• HS Hun Stoff
• H Impure Mustard
• HD Distilled Mustard
• HL Mustard/Lewisite
• HT Mustard/Agent T
• CX Phosgene Oxime
• L Lewisite

6
History of Blister Gas

• French quickly followed as did English. The US
  troops used French blister canisters and shells.
• Captain Lewis team discovers lewisite 1918.
• US production after WWI begins Pine Bluff and
  Aberdeen Proving Ground as chemical warfare
  department under war department forms in latter
  days of WWI. Especially from 1950 to 1969.

7
History of Blister Gases

• No use in WWII, Korea or Viet Nam of blister
  gases. Bari incident Dec 2 1943.
• 1981 Iraq uses HD against Iran.
• 1984 Iraq uses HD against Kurds.
• 1991 Iraq deploys HD but doesnt have a chance to
  use them.

8
History of Blister Gases

• United states ceased military production in 1969
  by presidential order.
• Soviets continued production until 1991. Then ?
• US must destroy its stockpiles of HD by April
  2007 by treaty. It is helping Russia destroy
  their stockpiles.
• There are 12 other vesicants including HN2
  (Mustargen).

9
WWI Mustard Casualties and Death
10
Additional Mustards

• After WWI, it was found that the addition of
  nitrogen as a substitute for sulfur offered
  certain advantages. Several Nitrogen mustards
  were developed, HN1, HN2 and HN3. HN2 eventually
  became Nitrogen Mustard. HN3 2,2,2-tri(chloroethy
  l) amine is felt to be the only one likely to be
  used for military purposes.

11
Physical Properties

• Thick oily amber to brown liquid which
  freezes/melts at 58 F.
• Heavier than air (vapor) or water (liquid).
• Persistent.
• Penetrates skin in 2 minutes.
• Causes cellular damage in 5 minutes.
• Delayed onset of clinical effects. 2-48 hours.

12
Unprotected Mustard Effects

• Vapor (mg.min/m3)
• Eye 10-50
• Airways 100-500
• Skin 200-1000
• Death 1500
• Liquid
• Blister 10?g
• Death 100 mg/kg

13
Skin

• 80 on skin is vaporized.
• A small amount remains fixed to the skin. Likes
  to attack moist areas like scrotum or anus.
• The rest becomes systemic, quickly cyclizes and
  alkylates DNA and protein.
• It has a radiomimetic effect on epithelial
  tissue, marrow, lymphoid tissue and nervous
  system.

14
Clinical Effects of HD

• Eye.
• Mild conjunctivitis, burning, blepharospasm.
• Moderate same as above plus lid inflammation,
  corneal roughening.
• Severe Corneal opacification, ulceration or
  perforation. Only 0.1 legally blind for Mustard
  attack.

15
Skin

• Erythema ? small vesicles ? coalesce into bullae.
• If liquid contact possible coagulation necrosis.

16
(No Transcript)
17
Respiratory

• Upper airways, nose pain and hemorrhage.
• Larynx Stridor, hoarseness.
• Tracheobronchial bronchospasm, pseudomembrane
  formation.
• Alveoli hemorrhagic edema with massive exposure
  only.

18
Marrow

• Damages stem cells as it is an alkylating agent.
• Decreases WBC, RBC and platelets.
• This occurs about Day 7 to 14.
• If WBC count goes below 2000, prognosis poor.

19
Gastrointestinal

• Early.
• Transient.
• Cholinergic effect.
• Late.
• 3 days -severe damage in some cases. Epithelial
  cytotoxic effects.

20
CNS

• Apathy.
• Euphoria.
• Coma.
• Convulsions.
• Death.
• Latter three with massive exposures.

21
Death

• Usually pulmonary with higher exposure
  concentrations.
• Secondary infection common and can be fatal.
• Radiomimetic effect of HD depresses immunity.

22
Diagnosis

• Delayed onset of clinical symptoms.
• Urinary thiodiglycol levels elevated.
• Possible chemical pneumonia manifestations on
  x-ray.
• Mainly a clinical diagnosis depending on the
  circumstances.
• M8, M9 ( paper if liquid Mustard).
• CAM.

23
Management

• Decontaminate early with soap and water or dilute
  bleach 1 to 10. Theoretically latter is better.
• Early decontamination within minutes is for the
  patients benefit.
• Later decontamination is for the health care
  teams benefit. Wear Class A or B protection if
  Liquid HD or you are uncertain.

24
Management

• Eyes Avoid topical anesthetics or analgesics.
• Use mydriatics, topical antibiotics.
• Vaseline on lids (Dont use eye patch.
• Sunglasses.

25
Skin

• Unroof blisters. Fluid is non-toxic.
• Debridement of burns.
• Soothing lotions.
• Frequent irrigations.
• Systemic analgesics.
• Electrolyte and fluid replacement but not like
  that for burns.

26
Airways

• Steam, Cough suppressants.
• Oxygen.
• Bronchodilators, Steroids.
• Early intubation may be required.
• Specific antibiotic administration. Avoid
  prophylactic antibiotics,
• Assisted ventilation.

27
Marrow

• May need to use
• Reverse isolation.
• Hormonal therapy.
• Marrow transplants.
• Cellular replacement i.e. platelet transfusions
  etc.

28
Long Term Effects of Mustards

• After WWI many suffered lingering effects over
  the next 20 years. As many were tobacco users it
  is uncertain what role HD played in aggravating
  asthma or COPD.
• It is a weak carcinogen in regard to pulmonary
  cancer but usually not with one or two exposures.
• It is not a human reproductive toxin though it is
  a mutagen.

29
Lewisite

• Same as Mustard only worse. It is
  2-chlorovinyl-dichloroarsine.
• Immediate effects. Never used in combat. Contains
  arsenic so has additional toxic potential.
• Has a Germanium odor.
• Effects eyes, skin, airways and capillaries.

30
General Information on Lewisite

• Brownish due to impurities, otherwise odorless
  and colorless.
• Hydrolyzes fast and is soluble in solvents.
• Disappears rapidly on a humid day but can be more
  persistent if mixed with mustard.
• Draeger tube for arsenicals but no CAM.
• Toole Army Depot.

31
More Lewisite Information

• Penetrates the skin rapidly and can produce
  arsenic poisoning.
• Interferes with lipoic acid and many sulfhydryl
  enzymes in the body.
• Personal Protection and Decontamination is the
  same as that for Mustard.
• Instantly damages.

32
Clinical Manifestations

• Instant blepharospasm. Depending on Ct, will
  cause corneal clouding, Painful, thicker skin
  blisters than mustard. Quicker skin absorption
  than mustard.
• Blisters of L start out in the center of an
  erythematous area whereas blisters of mustard are
  found like a string of pearls around the edge of
  an area of erythema.

33
Clinical Manifestations

• Even more likely than mustard to produce
  pulmonary edema due to capillary damage.
• May also cause anasarca. Hypovolemia, renal
  failure.

34
Treatment

• Supportive similar to mustard.
• Dimercaprol (BAL) 3mg/kg IM every 4 hours for 2
  days. 50 morbidity from BAL.
• Meso-dimercaptosuccinic acid (DMSA).
• 2,3 dimercapto 1- propanesulfonic acid (DMPS).

35
Phosgene Oxime (CX)

• Dichloroformoxime -The Most Caustic of Them All

36
General Comments

• Discovered 1929 Germany.
• Stockpiled.
• Can penetrate rubber and most other coverings.
• Colorless crystalline powder that melts at 40 C
  and boils at 120 C. Gives off highly toxic fumes.

37
Clinical Aspects

• 2 mg cause a necrosing cuastic burn to skin.
• Smaller amounts produce erythema, then urticaria.
  Not blisters. Immediate cagulation necrosis of
  the eye or skin. Skin turns white then sloughs.
  Eye immediately opacifies.
• No other agent produce this much immediate pain
  followed by tissue sloughing.
• Pulmonary edema and death.

38
Summary

• Vesicants have been used with devastating
  results.
• Though mortality is low with mustard, morbidity
  is high requiring specialized and prolonged care.
  Secondary infections are common. Scarring and
  pigmentation often result later.
• L and CX are even worse but have not been
  verified as being used.